4.0 2.0 ATL13_20250911191726_13452801_007_02.h5 /nasa-ngap/atl/tmpatl/ATL13_20250911191726_13452801_007_02.h5 ds_anom_trigger 9 ds_sseg_quality 4 ds_anom_trigger /ds_anom_trigger long_name String Anomaly Trigger Dimension Scale units String 1 source String dim_scale valid_min Int32 1 valid_max Int32 9 contentType String auxiliaryInformation description String Dimension scale indexing the short segment anomaly trigger array having nine elements. Index = 1 corresponds to coarse ht difference; Index = 2 corresponds to abnormal length; Index = 3 corresponds to histogram mode spread; Index = 4 corresponds to histogram mode count; Index = 5 corresponds to histogram mode intensity; Index = 6 corresponds to invalid long segment; Index = 7 corresponds to shore buffer designation; Index = 8 corresponds to insufficient signal phs; Index = 9 corresponds to unavailability of coarse water height against which to test. flag_meanings String coarse_ht_difference abnormal_length histogram_mode_spread histogram_mode_count histogram_mode_intensity invalid_long_segment shore_buffer_designation insufficient_signal_phs coarse_water_height_unavailable flag_values Int32 1 2 3 4 5 6 7 8 9 ds_sseg_quality /ds_sseg_quality long_name String Segment Quality Dimension Scale units String 1 source String dim_scale valid_min Int32 1 valid_max Int32 4 contentType String auxiliaryInformation description String Dimension scale indexing the short segment quality array. Index = 1 corresponds to nominal; Index = 2 corresponds to possible afterpulse; Index = 3 corresponds to possible impulse response; Index = 4 corresponds to possible TEP flag_meanings String nominal possible_afterpulse possible_impulse_response possible_TEP flag_values Int32 1 2 3 4 short_name String ATL13 level String L3A description String This data set (ATL13) contains along track surface heights of inland water bodies, including lakes, estuaries and rivers. Water surface slope and descriptive statistics are also provided. The data were acquired by the Advanced Topographic Laser Altimeter S Conventions String CF-1.6 contributor_name String Thomas A Neumann (thomas.neumann@nasa.gov), Thorsten Markus (thorsten.markus@nasa.gov), Suneel Bhardwaj (suneel.bhardwaj@nasa.gov) David W Hancock III (david.w.hancock@nasa.gov) contributor_role String Instrument Engineer, Investigator, Principle Investigator, Data Producer, Data Producer date_type String UTC featureType String trajectory geospatial_lat_units String degrees_north geospatial_lon_units String degrees_east granule_type String ATL13 identifier_product_doi_authority String http://dx.doi.org license String Data may not be reproduced or distributed without including the citation for this product included in this metadata. Data may not be distributed in an altered form without the written permission of the ICESat-2 Science Project Office at NASA/GSFC. naming_authority String http://dx.doi.org spatial_coverage_type String Horizontal standard_name_vocabulary String CF-1.6 time_type String CCSDS UTC-A date_created String 2025-12-22T18:32:36.000000Z hdfversion String HDF5 1.14.4 history String 2025-12-22T18:32:36.000000Z;c230515c-aaf1-3821-b287-d22fed4296fc;Created by PGE atlas_l3a_iw Version 4.1.1 identifier_file_uuid String c230515c-aaf1-3821-b287-d22fed4296fc identifier_product_format_version String 4.1 time_coverage_duration Float64 22630. time_coverage_end String 2025-09-12T01:34:36.000000Z time_coverage_start String 2025-09-11T19:17:26.000000Z geospatial_lat_min Float64 -90. geospatial_lon_min Float64 -180. geospatial_lat_max Float64 90. geospatial_lon_max Float64 180. publisher_name String NSIDC DAAC > NASA National Snow and Ice Data Center Distributed Active Archive Center publisher_email String nsidc@nsidc.org publisher_url String http://nsidc.org/daac/ title String ATLAS/ICESat-2 L3A Along Track Inland Surface Water Data identifier_product_type String ATL13 identifier_product_doi String doi:10.5067/ATLAS/ATL13.007 institution String National Aeronautics and Space Administration (NASA) creator_name String GSFC I-SIPS > ICESat-2 Science Investigator-led Processing System summary String The purpose of ATL13 is to provide along-track inland water surface heights and associated statistics. keywords String EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SURFACE WATER FEATURES > NONE > NONE > NONE > NONE keywords_vocabulary String NASA/GCMD Science Keywords citation String Cite these data in publications as follows: The data used in this study were produced by the ICESat-2 Science Project Office at NASA/GSFC. The data archive site is the NASA National Snow and Ice Data Center Distributed Active Archive Center. processing_level String 3A references String http://nsidc.org/data/icesat2/data.html project String ICESat-2 > Ice, Cloud, and land Elevation Satellite-2 instrument String ATLAS > Advanced Topographic Laser Altimeter System platform String ICESat-2 > Ice, Cloud, and land Elevation Satellite-2 source String Spacecraft orbit_info crossing_time 3 sc_orient_time 1 sc_orient_time /orbit_info/sc_orient_time long_name String Time of Last Spacecraft Orientation Change standard_name String time units String seconds since 2018-01-01 source String POD/PPD contentType String referenceInformation description String The time of the last spacecraft orientation change between forward, backward and transitional flight modes, expressed in seconds since the ATLAS SDP GPS Epoch. ICESat-2 is considered to be flying forward when the weak beams are leading the strong beams; and backward when the strong beams are leading the weak beams. ICESat-2 is considered to be in transition while it is maneuvering between the two orientations. Science quality is potentially degraded while in transition mode. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. crossing_time /orbit_info/crossing_time long_name String Ascending Node Crossing Time standard_name String time units String seconds since 2018-01-01 source String POD/PPD contentType String referenceInformation description String The time, in seconds since the ATLAS SDP GPS Epoch, at which the ascending node crosses the equator. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. orbit_number /orbit_info/crossing_time long_name String Orbit Number units String 1 source String Operations valid_min UInt16 1 valid_max UInt16 65000 contentType String referenceInformation description String Unique identifying number for each planned ICESat-2 orbit. coordinates String crossing_time sc_orient /orbit_info/sc_orient_time long_name String Spacecraft Orientation units String 1 source String POD/PPD valid_min Int8 0 valid_max Int8 2 contentType String referenceInformation description String This parameter tracks the spacecraft orientation between forward, backward and transitional flight modes. ICESat-2 is considered to be flying forward when the weak beams are leading the strong beams; and backward when the strong beams are leading the weak beams. ICESat-2 is considered to be in transition while it is maneuvering between the two orientations. Science quality is potentially degraded while in transition mode. coordinates String sc_orient_time flag_meanings String backward forward transition flag_values Int8 0 1 2 rgt /orbit_info/crossing_time long_name String Reference Ground track units String 1 source String POD/PPD valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT3 and GT4. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1387 RGTs. coordinates String crossing_time cycle_number /orbit_info/crossing_time long_name String Cycle Number units String 1 source String Operations valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String A count of the number of exact repeats of this reference orbit. coordinates String crossing_time lan /orbit_info/crossing_time long_name String Ascending Node Longitude units String degrees_east source String POD/PPD valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at the ascending node crossing. coordinates String crossing_time description String Contains orbit information. data_rate String Varies. Data are only provided when one of the stored values (besides time) changes. bounding_polygons lat24 11 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon25 23 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat21 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat28 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon15 25 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon7 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat18 15 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon3 23 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat14 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat25 23 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat8 15 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon26 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon9 13 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat4 11 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat3 23 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon17 11 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon11 37 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat7 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat20 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon14 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon28 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon31 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon35 11 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat15 25 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat22 17 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon13 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon33 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat5 13 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat19 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon2 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon5 13 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat16 13 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat12 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon16 13 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat27 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon21 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat30 15 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon10 13 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon22 17 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat32 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon29 23 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon24 11 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon34 15 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon12 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat13 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat23 11 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat29 23 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat31 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat6 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat34 15 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat2 49 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon32 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat1 15 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat33 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat26 51 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon30 15 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon19 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon23 11 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon18 15 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon6 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat17 11 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat9 13 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon1 15 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon27 51 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon4 11 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat10 13 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lat11 37 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. lon8 15 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lon20 49 long_name String Polygon Longitude units String degrees_east source String geo_poly valid_min Float64 -180. valid_max Float64 180. contentType String auxiliaryInformation description String Longitude values for a bounding polygon. lat35 11 long_name String Polygon Latitude units String degrees_north source String geo_poly valid_min Float64 -90. valid_max Float64 90. contentType String auxiliaryInformation description String Latitude values for a bounding polygon. description String Contains the bounding polygons associated with the input ATL03s. METADATA iso_19139_dataset_xml 1 long_name String ISO 19139 Dataset XML description String ISO 19139 Dataset XML iso_19139_series_xml 1 long_name String ISO 19139 Series XML description String ISO 19139 Series XML Description String ISO19115 Structured Metadata Represented within HDF5 AcquisitionInformation lidar pulse_rate String 10000 pps wavelength String 532 nm identifier String ATLAS type String Laser Altimeter description String ATLAS on ICESat-2 determines the range between the satellite and the Earth's surface by measuring the two-way time delay of short pulses of laser light that it transmits in six beams. It is different from previous operational ice-sheet altimeters in that it is a photon-counting LIDAR. ATLAS records a set of arrival times for individual photons, which are then analyzed to derive surface, vegetation, and cloud properties. ATLAS has six beams arranged in three pairs, so that it samples each of three reference pair tracks with a pair of beams; ATLAS transmits pulses at 10 kHz, giving approximately one pulse every 0.7 m along track; ATLAS's expected pointing control will be better than 90 m RMS. lidarDocument edition String Pre-Release publicationDate String 12/31/17 title String A document describing the ATLAS instrument will be provided by the ICESat-2 Project Science Office. platform identifier String ICESat-2 description String Ice, Cloud, and land Elevation Satellite-2 type String Spacecraft platformDocument edition String 31-Dec-16 publicationDate String 31-Dec-16 title String The Ice, Cloud, and land Elevation Satellite-2 (ICESat-2): Science requirements, concept, and implementation. Thorsten Markus, Tom Neumann, Anthony Martino, Waleed Abdalati, Kelly Brunt, Beata Csatho, Sinead Farrell, Helen Fricker, Alex Gardner, David Harding, Michael Jasinski, Ron Kwok, Lori Magruder, Dan Lubin, Scott Luthcke, James Morison, Ross Nelson, Amy Neuenschwander, Stephen Palm, Sorin Popescu, CK Shum, Bob E. Schutz, Benjamin Smith, Yuekui Yang, Jay Zwally. http://dx.doi.org/10.1016/j.rse.2016.12.029 DataQuality scope String NOT_SET CompletenessOmission evaluationMethodType String directInternal measureDescription String TBD nameOfMeasure String TBD unitofMeasure String TBD value String NOT_SET DomainConsistency evaluationMethodType String directInternal measureDescription String TBD nameOfMeasure String TBD unitofMeasure String TBD value String NOT_SET ProductSpecificationDocument ShortName String ATL13_SDP characterSet String utf8 language String eng publicationDate String Feb 2020 title String ICESat-2-SIPS-SPEC-4267 - ATLAS Science Algorithm Standard Data Product (SDP) Volume T12 (ATL13). Revision -. edition String v3.3 SeriesIdentification maintenanceAndUpdateFrequency String asNeeded maintenanceDate String SET_BY_META VersionID String 007 language String eng characterSet String utf8 pointOfContact String NSIDC DAAC > NASA National Snow and Ice Data Center Distributed Active Archive Center longName String ATLAS/ICESat-2 L3A Along Track Inland Surface Water Data shortName String ATL13 identifier_product_DOI String doi:10.5067/ATLAS/ATL13.007 revisionDate String 2022-08-09 resourceProviderOrganizationName String National Aeronautics and Space Administration (NASA) abstract String The ICESat-2 ATL13 standard data product contains along track surface height of inland water bodies. This product contains, for each beam, water surface height, slope, and rms aggregated into segments defined by approximately 100 signal photons. Also includes water surface slope and aspect between neighboring strong beams. purpose String The purpose of ATL13 is to provide along-track inland water surface heights and associated statistics. credit String The software that generates the ATL13 product was designed and implemented within the ICESat-2 Science Investigator-led Processing System at the NASA Goddard Space Flight Center in Greenbelt, Maryland. status String onGoing format String HDF formatVersion String 5 topicCategory String geoscientificInformation mission String ICESat-2 > Ice, Cloud, and land Elevation Satellite-2 DatasetIdentification spatialRepresentationType String along-track creationDate String 2025-12-22T18:32:36.000000Z uuid String c230515c-aaf1-3821-b287-d22fed4296fc fileName String ATL13_20250911191726_13452801_007_02.h5 VersionID String 007 language String eng characterSet String utf8 shortName String ATL13 originatorOrganizationName String GSFC I-SIPS > ICESat-2 Science Investigator-led Processing System abstract String The ICESat-2 ATL13 standard data product contains along track surface height of inland water bodies. This product contains, for each beam, water surface height, slope, and rms aggregated into segments defined by approximately 100 signal photons. Also includes water surface slope and aspect between neighboring strong beams. purpose String The purpose of ATL13 is to provide along-track inland water surface heights and associated statistics. credit String The software that generates the ATL13 product was designed and implemented within the ICESat-2 Science Investigator-led Processing System at the NASA Goddard Space Flight Center in Greenbelt, Maryland. status String onGoing topicCategory String geoscientificInformation Extent northBoundLatitude Float64 90. eastBoundLongitude Float64 180. southBoundLatitude Float64 -90. westBoundLongitude Float64 -180. rangeBeginningDateTime String 2025-09-11T19:17:26.000000Z rangeEndingDateTime String 2025-09-12T01:34:36.000000Z QADatasetIdentification creationDate String 2025-12-22T20:49:02.000000Z abstract String An ASCII product that contains statistical information on data product results. These statistics enable data producers and users to assess the quality of the data in the data product granule fileName String ATL13_20250911191726_13452801_007_02.qa Lineage Control description String Text-based keyword=value file generated automatically within the ICESat-2 data system that specifies all of the conditions required for each individual run of the software. fileName String CTL_atlas_l3a_iw_021426055.ctl shortName String CNTL version String 1 ANC38-13 description String ISO 19139 XML file containing DataSet-level metadata information. fileName String ANC38-13_20250523205159_007_01.xml shortName String ANC38-13 uuid String 527a0d6a-3fbd-3a9c-833e-a76aa0c2fffa version String 007 ANC36-13 description String ISO 19139 XML file containing Series-level metadata information. fileName String ANC36-13_20250523205158_007_01.xml shortName String ANC36-13 uuid String 434d6e13-f24e-3081-aff7-e3893a2b8945 version String 007 ANC26-13 description String HDF5 template file that defines the organization and default content of the product metadata. fileName String atl13_metadata_template.h5 shortName String ANC26-13 uuid String 92fd7663-ad71-378e-b85b-c7a1cc34b8ab version String 041 ATL03 description String ICESat-2 ATLAS L2A Global Geolocated Photon data products. fileName String ATL03_20250911211241_13462804_007_01.h5 ATL03_20250911211750_13462805_007_01.h5 ATL03_20250911212316_13462806_007_01.h5 ATL03_20250911213146_13462807_007_01.h5 ATL03_20250911213848_13462808_007_01.h5 ATL03_20250911215933_13462811_007_01.h5 ATL03_20250911220516_13462812_007_01.h5 ATL03_20250911221257_13462813_007_01.h5 ATL03_20250911221859_13462814_007_01.h5 ATL03_20250911222602_13472801_007_01.h5 ATL03_20250911223304_13472802_007_01.h5 ATL03_20250911224134_13472803_007_01.h5 ATL03_20250911224659_13472804_007_01.h5 ATL03_20250911225208_13472805_007_01.h5 ATL03_20250911225733_13472806_007_01.h5 ATL03_20250911230604_13472807_007_01.h5 ATL03_20250911231305_13472808_007_01.h5 ATL03_20250911232008_13472809_007_01.h5 ATL03_20250911232610_13472810_007_01.h5 ATL03_20250911233351_13472811_007_01.h5 ATL03_20250911233934_13472812_007_01.h5 ATL03_20250911234715_13472813_007_01.h5 ATL03_20250911235317_13472814_007_01.h5 ATL03_20250912000018_13482801_007_01.h5 ATL03_20250912000720_13482802_007_01.h5 ATL03_20250912001551_13482803_007_01.h5 ATL03_20250912002116_13482804_007_01.h5 ATL03_20250912002625_13482805_007_01.h5 ATL03_20250912003150_13482806_007_01.h5 ATL03_20250912005425_13482809_007_01.h5 ATL03_20250912010027_13482810_007_01.h5 ATL03_20250912010807_13482811_007_01.h5 ATL03_20250912011351_13482812_007_01.h5 ATL03_20250912012131_13482813_007_01.h5 ATL03_20250912012733_13482814_007_01.h5 shortName String ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 ATL03 uuid String 707d300c-60bd-329e-99e2-d7e3997e2f15 125c826a-0b21-3ea6-8146-41b31c27cc8c 12866cae-c5ac-3227-84ce-80a82279f8d7 ae21a86b-afc1-3239-9295-ccc06efd7466 ed468c36-b3e3-3d21-81c4-da02d09c47b0 9c8dbb0b-b248-3d2a-bb1e-f8ce3e90e276 48418869-16c8-3a8d-85d6-59687bab0c38 728afbd2-bc61-3d4c-b6a7-57d9a6fcc622 2d485087-6018-35aa-bcec-a4ed8c83f21a b2c0be1f-07ac-3d17-8517-0a13282469c0 bd818098-4f97-3bd8-a9e8-d93af3bc584a b35f2a1b-b429-361a-81cb-914bb748e06f 4db49d0c-fe4a-3745-a983-3f44984c62c2 d793a62d-0c6b-32e8-999d-4060908e1d3e 97f561fc-3559-3d9f-b35e-e48e6bbd38ae 4161332a-b682-3187-bc50-4fee81770963 a0e5297f-40a2-300a-a983-52aef7c05a66 8c3fe7b6-0286-336f-8b76-6c9fa5672349 8db6d4ae-73a3-3e36-8653-bed590fe309b 1345c50e-0179-34fd-a3b5-f9fad0125d2b 9e25e992-3ed2-3e7b-9d00-e6ab5d3f29a4 a610cfa4-f481-32ea-9cee-2a4af231d36c 77e67e93-5a61-3322-b5ea-2f468cc7cc8a da41c3d9-a29f-3b21-b4fb-789547abf2dc 597eb9db-acc9-31fa-a200-c13986f428f0 209f638a-0bbf-3f4c-bf0d-a9f60fbb8f5a 367b60b6-b080-35a6-9ff5-af6a5ee0de58 52679700-2416-382c-ad96-195122d90e0f c1441ce1-bbbe-3b5e-b690-8b23132a4579 970f9765-eab9-3c2b-8a9b-748348d3ff87 7ded6457-91af-3e9a-9036-82f603d60b23 6e423d94-7801-39ae-8d52-061a3ad80e5e fd67730b-a158-386a-9e0f-83deaf66b928 76372cd9-939c-3e3a-b27e-1c34afa824ad 6b8d0071-c0ac-385f-9d3f-64c3a987d732 version String 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 007 start_cycle Int32 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 end_cycle Int32 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 28 start_orbit Int32 38996 38996 38996 38996 38996 38996 38996 38996 38996 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38998 38998 38998 38998 38998 38998 38998 38998 38998 38998 38998 38998 end_orbit Int32 38996 38996 38996 38996 38996 38996 38996 38996 38996 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38997 38998 38998 38998 38998 38998 38998 38998 38998 38998 38998 38998 38998 start_rgt Int32 1346 1346 1346 1346 1346 1346 1346 1346 1346 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1348 1348 1348 1348 1348 1348 1348 1348 1348 1348 1348 1348 end_rgt Int32 1346 1346 1346 1346 1346 1346 1346 1346 1346 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1347 1348 1348 1348 1348 1348 1348 1348 1348 1348 1348 1348 1348 start_region Int32 4 5 6 7 8 11 12 13 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 2 3 4 5 6 9 10 11 12 13 14 end_region Int32 4 5 6 7 8 11 12 13 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 2 3 4 5 6 9 10 11 12 13 14 start_geoseg Int32 446047 555736 671060 852076 1001777 1443579 1565340 1728837 1857240 1 149699 330711 446034 555722 671047 852068 1001775 1151678 1280088 1443590 1565349 1728845 1857245 1 149696 330708 446033 555720 671049 1151688 1280098 1443599 1565353 1728847 1857246 end_geoseg Int32 555735 671059 852075 1001776 1151673 1565339 1728836 1857239 2007130 149698 330710 446033 555721 671046 852067 1001774 1151677 1280087 1443589 1565348 1728844 1857244 2007132 149695 330707 446032 555719 671048 852074 1280097 1443598 1565352 1728846 1857245 2007134 ATL09 description String ICESat-2 ATLAS L3A atmosphere data products. fileName String ATL09_20250911205144_13462801_007_01.h5 ATL09_20250911222602_13472801_007_01.h5 ATL09_20250912000018_13482801_007_01.h5 shortName String ATL09 ATL09 ATL09 uuid String 20800f06-ef53-305c-8ddb-7ef98589ae9a 4d1f8233-22da-38f2-be82-ae178b223964 5261c889-db07-308a-ade4-d4d9b8d7ccfc version String 007 007 007 start_cycle Int32 28 28 28 end_cycle Int32 28 28 28 start_orbit Int32 38996 38997 38998 end_orbit Int32 38996 38997 38998 start_rgt Int32 1346 1347 1348 end_rgt Int32 1346 1347 1348 start_region Int32 1 1 1 end_region Int32 14 14 14 start_geoseg Int32 551628 3 2 end_geoseg Int32 2007125 2007126 2007134 ANC19 description String TAI to UTC leapsecond file retrieved from ftp://maia.usno.navy.mil/ser7/tai-utc.dat fileName String tai_utc_2017.dat shortName String ANC19 uuid String 7c66d365-278a-31f7-8fe4-9c80e2f012e5 version String 001 ANC25-13 description String HDF5 template file that defines the organization and default content of the product. fileName String atl13_template.h5 shortName String ANC25-13 uuid String babdaeb6-b231-3658-9cd6-b4a60b095bd8 version String 041 ANC20-01 description String Water Basin shapefiles provided by the Inland Water ATBD lead. fileName String ATL13_Region_Mask_by_basins_20170201.dbf shortName String ANC20-01 uuid String 9d332759-a01c-3a75-a4ae-0b4306924e52 version String 20170201 ANC20-02 description String Water Body shapefiles provided by the Inland Water ATBD lead. fileName String ATL13_Inland_Water_Body_Mask_v3_20191220.dbf shortName String ANC20-02 uuid String 828c2c64-0165-3179-af17-fcc9721d4ceb version String 20191220 ProcessStep Browse processDescription String Browse processing is performed for each granule SIPS produces. The browse utility reads data from the granule and produces browse images as defined in the respective product ATBD. The utility then embeds each browse image into the product within the /Browse group. identifier String atlas_brw softwareVersion String Version 3.1.3 softwareDate String Apr 8 2025 softwareTitle String Creates ATLAS HDF5 browse files runTimeParameters String CTL_atlas_l3a_iw_021426055.ctl stepDateTime String 2025-12-22T20:49:05.000000Z Metadata processDescription String Metadata information is processed by the metadata utility for each granule produced by SIPS. During PGE processing, dynamic metadata are written to the product. Additional static information is provided with the metadata template. The metadata utility reads ISO Dataset and Series metadata files and updates the product with static information from within those files. The utility then merges the static and dynamic metadata to creates output ISO19139 Dataset and Series XML files. Finally the utility reads the ISO19139 Dataset and Series XML files into memory and stores the textual representations as attributes attached to the /METADATA group. identifier String atlas_meta softwareVersion String Version 5.1.3 softwareDate String Apr 8 2025 softwareTitle String Creates ATLAS XML metadata files runTimeParameters String CTL_atlas_l3a_iw_021426055.ctl stepDateTime String 2025-12-22T20:51:30.000000Z PGE ATBDDate String 12/04/2019 ATBDTitle String Algorithm Theoretical Basis Document (ATBD) for Inland Water Data Products ATL13 ATBDVersion String v.3 documentDate String Feb 2020 documentation String ATLAS Science Algorithm Software Design Description (SDD) - Volume 21 (atlas_l3a_iw) processDescription String Computes along-track inland water surface height, slope, and roughness for each ATLAS beam, and also aspect and maximum slope (or gradient) of the planar surface between adjacent strong beams. identifier String atlas_l3a_iw softwareVersion String Version 4.1.1 softwareDate String Jul 30 2025 softwareTitle String ASAS L3A Inland Water PGE runTimeParameters String CTL_atlas_l3a_iw_021426055.ctl stepDateTime String 2025-12-22T18:32:36.000000Z QA processDescription String QA processing is performed by an external utility on each granule produced by SIPS. The utility reads the granule, performs both generic and product-specific quality-assessment calculations, and writes a text-based quality assessment report. The name and creation data of this report are identified within the QADatasetIdentification metadata identifier String atl13_qa_util softwareVersion String Version 4.1 softwareDate String Apr 8 2025 softwareTitle String ATL13 QA Utility runTimeParameters String CTL_atlas_l3a_iw_021426055.ctl stepDateTime String 2025-12-22T20:49:02.000000Z gt1r delta_time 40048 segment_lon /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lat /gt1r/delta_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of reporting location for all short segment statistics. coordinates String delta_time segment_lon delta_time /gt1r/delta_time long_name String Delta Time standard_name String time units String seconds since 2018-01-01 source String ATL03 contentType String physicalMeasurement description String Number of GPS seconds since the ATLAS SDP epoch. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. coordinates String segment_lat segment_lon sseg_sig_ph_cnt /gt1r/delta_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String delta_time segment_lat segment_lon sseg_dist_from_eq /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Distance from equator to segment start standard_name String Along-track distance units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Along-track distance from the equator to the first photon in the short segment. coordinates String delta_time segment_lat segment_lon qf_bias_fit /gt1r/delta_time _FillValue Int8 127 long_name String Height Bias Fit Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The height bias fit flag is set based on the value of the goodness of fit bias estimated as the difference between the centroid elevations of the observed surface water histogram and fitted integrated water surface model histogram. The flag values are set as follows: = -3 if H_bias_fit < -0.10 (m); -2 if -0.10 <= H_bias_fit < -0.05;-1 when -0.05 <= H_bias_fit < -0.01; 0 if -0.01 <= H_bias_fit < 0.01 (m); 1 if 0.01 <= H_bias_fit < 0.05; 2 if 0.05 < H_bias_fit < 0.10; 3 if 0.10 <= H_bias_fit; 4 if H_bias_fit is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 equal_to_or_above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 sseg_mean_lon /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Mean longitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon cloud_flag_atm_atl09 /gt1r/delta_time _FillValue Int8 127 long_name String Cloud Flag Atm units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 10 contentType String modelResult description String Cloud flag from backscatter profile. coordinates String delta_time segment_lat segment_lon qf_ice /gt1r/delta_time _FillValue Int8 127 long_name String Ice Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The quality flag for ice describes the likelihood of ice on the short water body surface segment. 0 for QF_Bckgrd<= 2; 1 for 2 < QF_Bckgrd<= 4; 2 for 4 < QF_Bckgrd; 3 for (4 < QF_Bckgrd and QF_Cloud=1) coordinates String delta_time segment_lat segment_lon flag_meanings String qf_bckgrd_le_2 qf_bckgrd_le_4 qf_bckgrd_gt_4 qf_bckgrd_w_cloud flag_values Int8 0 1 2 3 transect_id /gt1r/delta_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String delta_time segment_lat segment_lon inland_water_body_type /gt1r/delta_time _FillValue Int8 127 long_name String Body type units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Type of Inland Water Body, where 1=Lake, 2=Known Reservoir, 3=(Reserved for future use), 4=Ephemeral Water, 5=River, 6=Estuary or Bay, 7=Coastal Water, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String Lake Known_Reservoir Reserved_for_future_use Ephemeral_Water River Estuary_or_Bay Coastal_Water Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 inland_water_body_id /gt1r/delta_time _FillValue Int32 2147483647 long_name String Body ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Identifying signature of an individual inland water body. Each body of water is represented by a unique numeric value. coordinates String delta_time segment_lat segment_lon sseg_end_lon /gt1r/delta_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon qf_subsurface_attenuation /gt1r/delta_time _FillValue Int8 127 long_name String Subsurface attenuation quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface attenuation was constrained during deconvolution by the minimum (initial) limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the subsurface attenuation fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for subsurface attenuation is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 segment_quality /gt1r/delta_time /ds_sseg_quality _FillValue Int32 2147483647 long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String delta_time segment_lat segment_lon segment_geoid /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Geoid units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Applicable mean-tide system geoid value at reporting location for all short segment statistics. (see geoid_free2mean to convert to the tide-free system.) coordinates String delta_time segment_lat segment_lon qf_sseg_length /gt1r/delta_time _FillValue Int8 127 long_name String Short Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Length of short segments flag. The flag is set as follows: 0 if sseg_length < 10 (meters); 1 if 10 <= sseg_length < 20 (meters); 2 if 20 <= sseg_length < 30 (meters); 3 if 30 <= sseg_length < 50 (meters); 4 if 50 <= sseg_length < 75 (meters); 5 if 75 <= sseg_length < 100 (meters); 6 if 100 <= sseg_length < 150 (meters); 7 if 150 <= sseg_length < 200 (meters); 8 if 200 <= sseg_length < 300 (meters); 9 if 300 <= sseg_length. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 below_threshold9 equal_to_or_above_threshold9 flag_values Int8 0 1 2 3 4 5 6 7 8 9 sseg_start_lon /gt1r/delta_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_tide_equilibrium /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Equilibrium units String meters source String ATL03 contentType String auxiliaryInformation description String Long period equilibrium tide self-consistent with ocean tide model (+- 0.04 m). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon qf_lseg_length /gt1r/delta_time _FillValue Int8 127 long_name String Long Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The Long Segment Length flag is set based on the length of the long segment. The flag is set as follows: 0 if Lseg_length < 500 (meters); 1 if 50 <= Lseg_length < 1500 (meters); 2 if 150 <= Lseg_length < 3000 (meters); 3 if 3000 <= Lseg_length coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 above_threshold4 flag_values Int8 0 1 2 3 significant_wave_ht /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String SWH units String meters source String section 5.3.3 (C) contentType String physicalMeasurement description String Significant wave height coordinates String delta_time segment_lat segment_lon bottom_lat /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Bottom latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon cycle_number /gt1r/delta_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String delta_time segment_lat segment_lon qf_subsurface_backscat_ampltd /gt1r/delta_time _FillValue Int8 127 long_name String Subsurface backscatter amplitude quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface backscatter amplitude was constrained during deconvolution by the minimum limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the backscatter amplitude fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for backscatter amplitude is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 water_depth /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water depth units String meters source String ATL13 ATBD, Section 5.3.4 (A) contentType String referenceInformation description String Depth from the mean water surface to detected bottom. coordinates String delta_time segment_lat segment_lon qf_bias_em /gt1r/delta_time _FillValue Int8 127 long_name String EM Bias Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The Electromagnetic Bias flag is set based on threshold checks for the estimated electromagnetic height bias. The flag is set as follows: -3 if H_bias_EM < -0.10 (m); -2 if -0.10 < H_bias_EM < -0.05; -1 if -0.05 <= H_bias_EM < -0.01; 0 if -0.01 <= H_bias_EM < 0.01 (m); 1 if 0.01 <= H_bias_EM < 0.05; 2 if 0.05 <= H_bias_EM < 0.10; 3 if 0.10 < H_bias_EM; 4 if H_bias_EM is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 segment_id_end /gt1r/delta_time long_name String Last ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String Last ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_stdev_vlseg /gt1r/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the very long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_apparent_ht /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Apparent height of the short segment, before adjustments are made by the algorithm, based on an average of heights within a designated range of the short segment mode. coordinates String delta_time segment_lat segment_lon stdev_water_surf /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface StDev units String meters source String section 5.3.3 (C) contentType String referenceInformation description String Derived standard deviation of water surface, calculated over long segments (when available) with result reported at each short segment location tag contained within. coordinates String delta_time segment_lat segment_lon met_wind10_atl09 /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height from ATL09 input. coordinates String delta_time segment_lat segment_lon qf_iwp /gt1r/delta_time _FillValue Int8 127 long_name String Inland Water Segment Processing Flag units String 1 source String Inland Water ATBD valid_min Int8 1 valid_max Int8 7 contentType String qualityInformation description String Describes the level of processing the inland water algorithm was able to perform based on the data available, ranging from one to 7. coordinates String delta_time segment_lat segment_lon flag_meanings String 1_short_segment 2_short_segments 3_to_5_short_segments 6_to_7_short_segments 8_to_9_short_segments 10_to_29_short_segments at_least_30_short_segments flag_values Int8 1 2 3 4 5 6 7 segment_podppd_flag /gt1r/delta_time _FillValue Int8 0 long_name String POD_PPD Flag units String 1 source String ATL02, ANC04, ANC05 valid_min Int8 0 valid_max Int8 7 contentType String referenceInformation description String Composite POD/PPD flag that indicates the quality of input geolocation products for the utilized ATL03 segments on an ATL13 short segment output basis. A non-zero value may indicate that geolocation solutions are degraded or that ATLAS is within a calibration scan period (CAL). The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible non-CAL values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE; possible CAL values are: 4=CAL_NOMINAL; 5=CAL_POD_DEGRADE; 6=CAL_PPD_DEGRADE; 7=CAL_PODPPD_DEGRADE; coordinates String delta_time flag_meanings String nominal pod_degrade ppd_degrade podppd_degrade cal_nominal cal_pod_degrade cal_ppd_degrade cal_podppd_degrade flag_values Int8 0 1 2 3 4 5 6 7 qf_ht_adj /gt1r/delta_time _FillValue Int8 127 long_name String Height adjustment Quality Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (C) valid_min Int8 -4 valid_max Int8 5 contentType String qualityInformation description String Flag representing the range of height, defined in 5.3.5 (C), which has been added to the apparent surface height due to frame of reference scaling during deconvolution analysis. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 equal_to_or_above_threshold8 invalid flag_values Int8 -4 -3 -2 -1 0 1 2 3 4 5 segment_full_sat_fract /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Full Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be fully saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon segment_id_beg /gt1r/delta_time long_name String First ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String First ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_subsurf_anomaly /gt1r/delta_time _FillValue Int8 127 long_name String Subsurface Anomaly Quality Flag units String 1 source String Inland Water ATBD 5.3.4(A) valid_min Int8 1 valid_max Int8 3 contentType String qualityInformation description String Describes the likelihood that the bottom or other subsurface anomaly is bottom based on the threshold value at which an anomaly was found. 1 = Subsurface anomaly due to bottom likely; 2 = Subsurface signal may indicate bottom or other anomaly; 3 = Possible subsurface anomaly; invalid = No subsurface anomaly detected coordinates String delta_time segment_lat segment_lon flag_meanings String bottom_likely bottom_or_other_anomaly possible_subsurface_anomaly flag_values Int8 1 2 3 subsurface_attenuation /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface Attenuation units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Subsurface attenuation coefficient. coordinates String delta_time segment_lat segment_lon layer_flag_atl09 /gt1r/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Consolidated cloud flag. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_region /gt1r/delta_time _FillValue Int32 2147483647 long_name String Body region units String 1 source String ATL13 ATBD, Section 5.3.1 (A) contentType String referenceInformation description String ATL13-created shapefile representing relevant bodies of water over which to implement the ATL13 water surface finding algorithm only within a region of processing interest. coordinates String delta_time segment_lat segment_lon sseg_end_lat /gt1r/delta_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Latitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon cloud_flag_asr_atl09 /gt1r/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 5 contentType String modelResult description String Cloud probability from ASR. coordinates String delta_time segment_lat segment_lon flag_meanings String clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence flag_values Int8 0 1 2 3 4 5 _FillValue Int8 127 long_name String Cloud Flag ASR ice_flag /gt1r/delta_time _FillValue Int8 127 long_name String Ice Flag units String 1 source String ATL13 ATBD, section 5.2 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Describes likelihood of ice on water surface short segment. coordinates String delta_time segment_lat segment_lon flag_meanings String no_ice ice flag_values Int8 0 1 sseg_start_lat /gt1r/delta_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_ref_elev /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String elevation standard_name String elevation units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from east-north plane and positive towards up. coordinates String delta_time segment_lat segment_lon segment_apparent_stdev /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent StDev units String meters source String section 5.3.2 (C) contentType String referenceInformation description String Standard deviation of short segment photon height in the short segment with signal classification >= sig_threshold. coordinates String delta_time segment_lat segment_lon ht_ortho /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height EGM2008 converted from ellipsoidal height. coordinates String delta_time segment_lat segment_lon alpha_mle /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Maximum likelihood alpha units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Alpha calculated by maximum likelihood analysis of the subsurface profile range. coordinates String delta_time segment_lat segment_lon rgt /gt1r/delta_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String delta_time segment_lat segment_lon ht_water_surf /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water surface height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Water surface height, reported for each short segment (default length = approximately 100 signal photons) with reference to WGS84 ellipsoid coordinates String delta_time segment_lat segment_lon segment_near_sat_fract /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Near Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be nearly saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon err_ht_water_surf /gt1r/delta_time units String 1 _FillValue Float32 3.402823466e+38 long_name String Height Error source String section 5.3.3 (C) contentType String qualityInformation description String Error included in heights reported in ht_water_surf. coordinates String delta_time segment_lat segment_lon bottom_lon /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon segment_bias_fit /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Goodness of fit bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Bias contribution from goodness of observation/system response fit. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon atl13refid /gt1r/delta_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id coordinates String delta_time segment_lat segment_lon qf_cloud /gt1r/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL09 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String This flag is a combination of multiple flags (cloud_flag_atm, cloud_flag_asr, and bsnow_con) and takes daytime/nighttime into consideration. A value of 1 means clouds or blowing snow are likely present. A value of 0 indicates the likely absence of clouds or blowing snow. From the ATL09 data closest to the segment time. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_source /gt1r/delta_time _FillValue Int8 127 long_name String Body source units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Source of Inland Water Body shape, where 1=HydroLAKES, 2=Global Lakes and Wetlands Database, 3=Named Marine Water Bodies, 4=GSHHG Shoreline, 5=Global River Widths from Landsat, 6=Reserved, 7=Reserved, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String HydroLAKES Global_Lakes_and_Wetlands_Database Named_Marine_Water_Bodies GSHHG_Shoreline Global_River_Widths_from_Landsat Reserved Reserved Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 sseg_length /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length standard_name String Length units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Distance from the first to the last photon in the short segment. coordinates String delta_time segment_lat segment_lon segment_tide_earth_free2mean /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Earth Tide Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Segment rate value to convert solid earth tide from the tide-free system that was applied in ATL03 to photon heights to the ht_water_surf to the mean-tide system. Subtract value from ht_water_surf to reference it in the mean-tide system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_stdev_lseg /gt1r/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_dem_source /gt1r/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int32 0 valid_max Int32 4 contentType String referenceInformation description String Flag equal to the source of the selected photon (in hierarchy of Arctic/Global/MSS/Antarctic). Values: 0=None, 1=Arctic, 2=Global, 3=MSS, 4=Antarctic. coordinates String delta_time segment_lat segment_lon flag_meanings String none arctic global mss antarctic flag_values Int32 0 1 2 3 4 _FillValue Int32 2147483647 long_name String dem source flag segment_fpb_correction /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String First photon bias correction units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String First photon bias correction. May be applied at user disrection by subtracting from mean height produts ht_ortho and ht_water_surf. coordinates String delta_time segment_lat segment_lon segment_azimuth /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Azimuth standard_name String azimuth units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. coordinates String delta_time segment_lat segment_lon inland_water_body_size /gt1r/delta_time _FillValue Int8 127 long_name String Body size units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 0 valid_max Int8 9 contentType String referenceInformation description String Size of Inland Water Body, A=area, where 0=Not_Assigned, 1=A>10,000 sq km, 2=10,000>A>=1,000, 3=1,000>A>=100, 4=100>A>=10, 5=10>A>=1, 6=1>A>=0.1, 7=0.01>A, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String not_assigned area_gt_10000 10000_gt_area_ge_1000 1000_gt_area_ge_100 100_gt_area_ge_10 10_gt_area_ge_1 1_gt_area_ge_0.1 0.01_gt_area Reserved Reserved flag_values Int8 0 1 2 3 4 5 6 7 8 9 met_wind10_atl13 /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height, based on derived water surface wave height. coordinates String delta_time segment_lat segment_lon snow_ice_atl09 /gt1r/delta_time _FillValue Int32 2147483647 long_name String Snow Ice Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) contentType String modelResult description String NOAA snow/ice flag scaled by ATL09 (0=ice-free water, 1=snow-free land, 2=snow, 3=ice, 127=invalid) coordinates String delta_time segment_lat segment_lon flag_meanings String ice_free_water snow_free_land snow ice invalid flag_values Int32 0 1 2 3 127 segment_tide_ocean /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Ocean units String meters source String ATL03 contentType String auxiliaryInformation description String Ocean tides including diurnal and semi-diurnal (harmonic analysis (+-4 m)). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon err_slope_trk /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Slope Error units String 1 source String section 5.3.3 (C) contentType String qualityInformation description String Error included in segment_slope_trk_local. coordinates String delta_time segment_lat segment_lon segment_slope_trk_bdy /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water Body Slope units String m/m source String ATL13 ATBD, Section 5.3.5 (A) contentType String physicalMeasurement description String Along track water body surface slope, reported per short segment ID per water body. coordinates String delta_time segment_lat segment_lon sseg_mean_lat /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Mean latitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon segment_geoid_free2mean /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Geoid Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Value to convert segment geoid heights from the mean-tide system to the tide-free system. Subtract this value from mean-tide system segment_geoid (on ATL13) to get geoid heights in the tide-free system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_spec_width /gt1r/delta_time _FillValue Int8 127 long_name String Spectral width Flag units String 1 source String ATL13 ATBD, Section 4.8.8 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Spectral moments width flag. The flag is set as follows: 0 when spec_width is invalid; 1 when 0 <= spec_width <= 0.2; 2 when 0.2 < spec_width <= 0.3; 3 when 0.3 < spec_width <= 0.4; 4 when 0.4 < spec_width <= 0.5; 5 when 0.5 < spec_width <= 0.6; 6 when 0.6 < spec_width <= 0.7; 7 when 0.7 < spec_width <= 0.8; 8 when 0.8 < spec_width <= 0.9; 9 when 0.9 < spec_width. coordinates String delta_time segment_lat segment_lon flag_meanings String invalid 0<=spec_width<=0.2 0.2<spec_width<=0.3 0.3<spec_width<=0.4 0.4<spec_width<=0.5 0.5<spec_width<=0.6 0.6<spec_width<=0.7 0.7<spec_width<=0.8 0.8<spec_width<=0.9 0.9<spec_width flag_values Int8 0 1 2 3 4 5 6 7 8 9 qf_bckgrd /gt1r/delta_time _FillValue Int8 127 long_name String Background Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 6 contentType String qualityInformation description String Describes the degree of background photons present in each short segment. bckgrd_dnsty_threshold1= 0.001 (counts per bi per Lseg); bckgrd_dnsty_threshold2= 0.01 (counts per bin per Lseg); bckgrd_dnsty_threshold3= 0.05 (counts per bin per Lseg); bckgrd_dnsty_threshold4= 0.1 (counts per bin per Lseg); bckgrd_dnsty_threshold5= 0.3 (counts per bin per Lseg); bckgrd_dnsty_threshold6= 0.5 (counts per bin per Lseg) coordinates String delta_time segment_lat segment_lon flag_meanings String equal_to_or_below_threshold1 equal_to_or_below_threshold2 equal_to_or_below_threshold3 equal_to_or_below_threshold4 equal_to_or_below_threshold5 equal_to_or_below_threshold6 above_threshold6 flag_values Int8 0 1 2 3 4 5 6 sseg_mean_time /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean time standard_name String time units String Seconds since 2018-01-01 source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Mean time of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon met_ts_atl09 /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface temperature standard_name String temperature units String K source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Surface (skin) temperature from ATL09. coordinates String delta_time segment_lat segment_lon segment_bias_em /gt1r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Electromagnetic bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Electromagnetic bias. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon segment_dem_ht /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String DEM Height units String meters source String ATL13 ATBD, Section 5.3.5 contentType String referenceInformation description String DEM height relative to WGS-84 ellipsoid, reported at the short segment rate. coordinates String delta_time segment_lat segment_lon subsurface_backscat_ampltd /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface backscatter amplitude units String 1 source String Section 5.3.4 (A) contentType String modelResult description String Subsurface backscatter amplitude, described in section 4.5.3, reported per long segment (default length = 10 short segments = approximately 1000 signal photons). coordinates String delta_time segment_lat segment_lon segment_dac /gt1r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment DAC units String meters source String ATBD Section 5.3.5A contentType String auxiliaryInformation description String Dynamic atmospheric correction (DAC) includes inverted barometer (IB) effect (+- 5 cm). Although available at short segment rate for all water body types, value is provided mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon DODS_EXTRA Container Unlimited_Dimension String delta_time description String Contains per-beam data products. data_rate String Data within this group are stored at the inland water short segment rate (/ancillary_data/inland_water/s_seg2). atlas_pce String pce3 atlas_beam_type String strong groundtrack_id String gt1r atmosphere_profile String profile_1 atlas_spot_number String 5 sc_orientation String Forward anom_ssegs anom_sseg_time 7256 anom_sseg_lat /gt1r/anom_ssegs/anom_sseg_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of the short segment (mean of signal class >=2 ph Lats). coordinates String anom_sseg_time anom_sseg_lon anom_sseg_time /gt1r/anom_ssegs/anom_sseg_time long_name String Delta Time standard_name String time units String sec source String ATL13 ATBD, Table 5-4b contentType String physicalMeasurement description String Time of the short segment (mean of signal class >=2 ph time). coordinates String anom_sseg_lat anom_sseg_lon anom_sseg_lon /gt1r/anom_ssegs/anom_sseg_time long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of the short segment (mean of signal class >=2 ph Lons). coordinates String anom_sseg_time anom_sseg_lat transect_id /gt1r/anom_ssegs/anom_sseg_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon cycle_number /gt1r/anom_ssegs/anom_sseg_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon rgt /gt1r/anom_ssegs/anom_sseg_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_sig_ph_cnt /gt1r/anom_ssegs/anom_sseg_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_trigger_flag /gt1r/anom_ssegs/anom_sseg_time /ds_anom_trigger _FillValue Int8 127 long_name String Anomalous classification flag units String 1 source String ATL13 ATBD, Table 5-4b valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Nine element array describing justification for short segment classification as anomalous, where for each element 0 = not triggered as anomalous and 1 = triggered as anomalous due to any of the following causes: [element 1=coarse ht difference, element 2=abnormal length, element 3= histogram mode spread, element 4=histogram mode count, element 5=histogram mode intensity, element 6=invalid long segment, element 7=shore buffer designation, element 8=insufficient signal phs, element 9=transect coarse water height unavailable against which to test short segment height] coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon flag_meanings String not_triggered_as_anomalous triggered_as_anomalous flag_values Int8 0 1 anom_sseg_stdev /gt1r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Segment standard deviation units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Standard deviation of anomalous short segment photon height in the anomalous short segment with signal classification >= 2. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_ht_delta /gt1r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Height difference units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height difference between anom_sseg_mode of the anomalous short segment and the transect coarse_transect_ht. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_length /gt1r/anom_ssegs/anom_sseg_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Length of the short segment, based on end points computed by the average of sseg_endpoint_avg_n signal photons. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lon /gt1r/anom_ssegs/anom_sseg_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String End longitude of the anomalous short segment, based on the average longitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon coarse_transect_ht /gt1r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Coarse water height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Coarse water height of transect. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon atl13refid /gt1r/anom_ssegs/anom_sseg_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mode /gt1r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Anomalous mode bin height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height of anomalous short segment as determined by histogram bin mode. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_quality /gt1r/anom_ssegs/anom_sseg_time /ds_sseg_quality long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each anomalous short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon _FillValue Int32 2147483647 anom_sseg_start_lon /gt1r/anom_ssegs/anom_sseg_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Start longitude of the anomalous short segment, based on the average longitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mean_ht_ortho /gt1r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height of anomalous short segment as determined by the mean of photon orthometric heights in the anomalous short segment with signal classification >2 coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_start_lat /gt1r/anom_ssegs/anom_sseg_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Start latitude of the anomalous short segment, based on the average latitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lat /gt1r/anom_ssegs/anom_sseg_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String End latitude of the anomalous short segment, based on the average latitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon DODS_EXTRA Container Unlimited_Dimension String anom_sseg_time description String Contains per-beam anomalous short segment output parameters. gt2r delta_time 36040 segment_lon /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lat /gt2r/delta_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of reporting location for all short segment statistics. coordinates String delta_time segment_lon delta_time /gt2r/delta_time long_name String Delta Time standard_name String time units String seconds since 2018-01-01 source String ATL03 contentType String physicalMeasurement description String Number of GPS seconds since the ATLAS SDP epoch. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. coordinates String segment_lat segment_lon sseg_sig_ph_cnt /gt2r/delta_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String delta_time segment_lat segment_lon sseg_dist_from_eq /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Distance from equator to segment start standard_name String Along-track distance units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Along-track distance from the equator to the first photon in the short segment. coordinates String delta_time segment_lat segment_lon qf_bias_fit /gt2r/delta_time _FillValue Int8 127 long_name String Height Bias Fit Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The height bias fit flag is set based on the value of the goodness of fit bias estimated as the difference between the centroid elevations of the observed surface water histogram and fitted integrated water surface model histogram. The flag values are set as follows: = -3 if H_bias_fit < -0.10 (m); -2 if -0.10 <= H_bias_fit < -0.05;-1 when -0.05 <= H_bias_fit < -0.01; 0 if -0.01 <= H_bias_fit < 0.01 (m); 1 if 0.01 <= H_bias_fit < 0.05; 2 if 0.05 < H_bias_fit < 0.10; 3 if 0.10 <= H_bias_fit; 4 if H_bias_fit is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 equal_to_or_above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 sseg_mean_lon /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Mean longitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon cloud_flag_atm_atl09 /gt2r/delta_time _FillValue Int8 127 long_name String Cloud Flag Atm units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 10 contentType String modelResult description String Cloud flag from backscatter profile. coordinates String delta_time segment_lat segment_lon qf_ice /gt2r/delta_time _FillValue Int8 127 long_name String Ice Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The quality flag for ice describes the likelihood of ice on the short water body surface segment. 0 for QF_Bckgrd<= 2; 1 for 2 < QF_Bckgrd<= 4; 2 for 4 < QF_Bckgrd; 3 for (4 < QF_Bckgrd and QF_Cloud=1) coordinates String delta_time segment_lat segment_lon flag_meanings String qf_bckgrd_le_2 qf_bckgrd_le_4 qf_bckgrd_gt_4 qf_bckgrd_w_cloud flag_values Int8 0 1 2 3 transect_id /gt2r/delta_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String delta_time segment_lat segment_lon inland_water_body_type /gt2r/delta_time _FillValue Int8 127 long_name String Body type units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Type of Inland Water Body, where 1=Lake, 2=Known Reservoir, 3=(Reserved for future use), 4=Ephemeral Water, 5=River, 6=Estuary or Bay, 7=Coastal Water, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String Lake Known_Reservoir Reserved_for_future_use Ephemeral_Water River Estuary_or_Bay Coastal_Water Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 inland_water_body_id /gt2r/delta_time _FillValue Int32 2147483647 long_name String Body ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Identifying signature of an individual inland water body. Each body of water is represented by a unique numeric value. coordinates String delta_time segment_lat segment_lon sseg_end_lon /gt2r/delta_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon qf_subsurface_attenuation /gt2r/delta_time _FillValue Int8 127 long_name String Subsurface attenuation quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface attenuation was constrained during deconvolution by the minimum (initial) limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the subsurface attenuation fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for subsurface attenuation is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 segment_quality /gt2r/delta_time /ds_sseg_quality _FillValue Int32 2147483647 long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String delta_time segment_lat segment_lon segment_geoid /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Geoid units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Applicable mean-tide system geoid value at reporting location for all short segment statistics. (see geoid_free2mean to convert to the tide-free system.) coordinates String delta_time segment_lat segment_lon qf_sseg_length /gt2r/delta_time _FillValue Int8 127 long_name String Short Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Length of short segments flag. The flag is set as follows: 0 if sseg_length < 10 (meters); 1 if 10 <= sseg_length < 20 (meters); 2 if 20 <= sseg_length < 30 (meters); 3 if 30 <= sseg_length < 50 (meters); 4 if 50 <= sseg_length < 75 (meters); 5 if 75 <= sseg_length < 100 (meters); 6 if 100 <= sseg_length < 150 (meters); 7 if 150 <= sseg_length < 200 (meters); 8 if 200 <= sseg_length < 300 (meters); 9 if 300 <= sseg_length. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 below_threshold9 equal_to_or_above_threshold9 flag_values Int8 0 1 2 3 4 5 6 7 8 9 sseg_start_lon /gt2r/delta_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_tide_equilibrium /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Equilibrium units String meters source String ATL03 contentType String auxiliaryInformation description String Long period equilibrium tide self-consistent with ocean tide model (+- 0.04 m). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon qf_lseg_length /gt2r/delta_time _FillValue Int8 127 long_name String Long Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The Long Segment Length flag is set based on the length of the long segment. The flag is set as follows: 0 if Lseg_length < 500 (meters); 1 if 50 <= Lseg_length < 1500 (meters); 2 if 150 <= Lseg_length < 3000 (meters); 3 if 3000 <= Lseg_length coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 above_threshold4 flag_values Int8 0 1 2 3 significant_wave_ht /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String SWH units String meters source String section 5.3.3 (C) contentType String physicalMeasurement description String Significant wave height coordinates String delta_time segment_lat segment_lon bottom_lat /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Bottom latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon cycle_number /gt2r/delta_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String delta_time segment_lat segment_lon qf_subsurface_backscat_ampltd /gt2r/delta_time _FillValue Int8 127 long_name String Subsurface backscatter amplitude quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface backscatter amplitude was constrained during deconvolution by the minimum limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the backscatter amplitude fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for backscatter amplitude is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 water_depth /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water depth units String meters source String ATL13 ATBD, Section 5.3.4 (A) contentType String referenceInformation description String Depth from the mean water surface to detected bottom. coordinates String delta_time segment_lat segment_lon qf_bias_em /gt2r/delta_time _FillValue Int8 127 long_name String EM Bias Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The Electromagnetic Bias flag is set based on threshold checks for the estimated electromagnetic height bias. The flag is set as follows: -3 if H_bias_EM < -0.10 (m); -2 if -0.10 < H_bias_EM < -0.05; -1 if -0.05 <= H_bias_EM < -0.01; 0 if -0.01 <= H_bias_EM < 0.01 (m); 1 if 0.01 <= H_bias_EM < 0.05; 2 if 0.05 <= H_bias_EM < 0.10; 3 if 0.10 < H_bias_EM; 4 if H_bias_EM is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 segment_id_end /gt2r/delta_time long_name String Last ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String Last ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_stdev_vlseg /gt2r/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the very long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_apparent_ht /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Apparent height of the short segment, before adjustments are made by the algorithm, based on an average of heights within a designated range of the short segment mode. coordinates String delta_time segment_lat segment_lon stdev_water_surf /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface StDev units String meters source String section 5.3.3 (C) contentType String referenceInformation description String Derived standard deviation of water surface, calculated over long segments (when available) with result reported at each short segment location tag contained within. coordinates String delta_time segment_lat segment_lon met_wind10_atl09 /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height from ATL09 input. coordinates String delta_time segment_lat segment_lon qf_iwp /gt2r/delta_time _FillValue Int8 127 long_name String Inland Water Segment Processing Flag units String 1 source String Inland Water ATBD valid_min Int8 1 valid_max Int8 7 contentType String qualityInformation description String Describes the level of processing the inland water algorithm was able to perform based on the data available, ranging from one to 7. coordinates String delta_time segment_lat segment_lon flag_meanings String 1_short_segment 2_short_segments 3_to_5_short_segments 6_to_7_short_segments 8_to_9_short_segments 10_to_29_short_segments at_least_30_short_segments flag_values Int8 1 2 3 4 5 6 7 segment_podppd_flag /gt2r/delta_time _FillValue Int8 0 long_name String POD_PPD Flag units String 1 source String ATL02, ANC04, ANC05 valid_min Int8 0 valid_max Int8 7 contentType String referenceInformation description String Composite POD/PPD flag that indicates the quality of input geolocation products for the utilized ATL03 segments on an ATL13 short segment output basis. A non-zero value may indicate that geolocation solutions are degraded or that ATLAS is within a calibration scan period (CAL). The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible non-CAL values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE; possible CAL values are: 4=CAL_NOMINAL; 5=CAL_POD_DEGRADE; 6=CAL_PPD_DEGRADE; 7=CAL_PODPPD_DEGRADE; coordinates String delta_time flag_meanings String nominal pod_degrade ppd_degrade podppd_degrade cal_nominal cal_pod_degrade cal_ppd_degrade cal_podppd_degrade flag_values Int8 0 1 2 3 4 5 6 7 qf_ht_adj /gt2r/delta_time _FillValue Int8 127 long_name String Height adjustment Quality Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (C) valid_min Int8 -4 valid_max Int8 5 contentType String qualityInformation description String Flag representing the range of height, defined in 5.3.5 (C), which has been added to the apparent surface height due to frame of reference scaling during deconvolution analysis. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 equal_to_or_above_threshold8 invalid flag_values Int8 -4 -3 -2 -1 0 1 2 3 4 5 segment_full_sat_fract /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Full Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be fully saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon segment_id_beg /gt2r/delta_time long_name String First ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String First ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_subsurf_anomaly /gt2r/delta_time _FillValue Int8 127 long_name String Subsurface Anomaly Quality Flag units String 1 source String Inland Water ATBD 5.3.4(A) valid_min Int8 1 valid_max Int8 3 contentType String qualityInformation description String Describes the likelihood that the bottom or other subsurface anomaly is bottom based on the threshold value at which an anomaly was found. 1 = Subsurface anomaly due to bottom likely; 2 = Subsurface signal may indicate bottom or other anomaly; 3 = Possible subsurface anomaly; invalid = No subsurface anomaly detected coordinates String delta_time segment_lat segment_lon flag_meanings String bottom_likely bottom_or_other_anomaly possible_subsurface_anomaly flag_values Int8 1 2 3 subsurface_attenuation /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface Attenuation units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Subsurface attenuation coefficient. coordinates String delta_time segment_lat segment_lon layer_flag_atl09 /gt2r/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Consolidated cloud flag. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_region /gt2r/delta_time _FillValue Int32 2147483647 long_name String Body region units String 1 source String ATL13 ATBD, Section 5.3.1 (A) contentType String referenceInformation description String ATL13-created shapefile representing relevant bodies of water over which to implement the ATL13 water surface finding algorithm only within a region of processing interest. coordinates String delta_time segment_lat segment_lon sseg_end_lat /gt2r/delta_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Latitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon cloud_flag_asr_atl09 /gt2r/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 5 contentType String modelResult description String Cloud probability from ASR. coordinates String delta_time segment_lat segment_lon flag_meanings String clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence flag_values Int8 0 1 2 3 4 5 _FillValue Int8 127 long_name String Cloud Flag ASR ice_flag /gt2r/delta_time _FillValue Int8 127 long_name String Ice Flag units String 1 source String ATL13 ATBD, section 5.2 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Describes likelihood of ice on water surface short segment. coordinates String delta_time segment_lat segment_lon flag_meanings String no_ice ice flag_values Int8 0 1 sseg_start_lat /gt2r/delta_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_ref_elev /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String elevation standard_name String elevation units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from east-north plane and positive towards up. coordinates String delta_time segment_lat segment_lon segment_apparent_stdev /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent StDev units String meters source String section 5.3.2 (C) contentType String referenceInformation description String Standard deviation of short segment photon height in the short segment with signal classification >= sig_threshold. coordinates String delta_time segment_lat segment_lon ht_ortho /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height EGM2008 converted from ellipsoidal height. coordinates String delta_time segment_lat segment_lon alpha_mle /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Maximum likelihood alpha units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Alpha calculated by maximum likelihood analysis of the subsurface profile range. coordinates String delta_time segment_lat segment_lon rgt /gt2r/delta_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String delta_time segment_lat segment_lon ht_water_surf /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water surface height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Water surface height, reported for each short segment (default length = approximately 100 signal photons) with reference to WGS84 ellipsoid coordinates String delta_time segment_lat segment_lon segment_near_sat_fract /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Near Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be nearly saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon err_ht_water_surf /gt2r/delta_time units String 1 _FillValue Float32 3.402823466e+38 long_name String Height Error source String section 5.3.3 (C) contentType String qualityInformation description String Error included in heights reported in ht_water_surf. coordinates String delta_time segment_lat segment_lon bottom_lon /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon segment_bias_fit /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Goodness of fit bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Bias contribution from goodness of observation/system response fit. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon atl13refid /gt2r/delta_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id coordinates String delta_time segment_lat segment_lon qf_cloud /gt2r/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL09 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String This flag is a combination of multiple flags (cloud_flag_atm, cloud_flag_asr, and bsnow_con) and takes daytime/nighttime into consideration. A value of 1 means clouds or blowing snow are likely present. A value of 0 indicates the likely absence of clouds or blowing snow. From the ATL09 data closest to the segment time. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_source /gt2r/delta_time _FillValue Int8 127 long_name String Body source units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Source of Inland Water Body shape, where 1=HydroLAKES, 2=Global Lakes and Wetlands Database, 3=Named Marine Water Bodies, 4=GSHHG Shoreline, 5=Global River Widths from Landsat, 6=Reserved, 7=Reserved, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String HydroLAKES Global_Lakes_and_Wetlands_Database Named_Marine_Water_Bodies GSHHG_Shoreline Global_River_Widths_from_Landsat Reserved Reserved Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 sseg_length /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length standard_name String Length units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Distance from the first to the last photon in the short segment. coordinates String delta_time segment_lat segment_lon segment_tide_earth_free2mean /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Earth Tide Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Segment rate value to convert solid earth tide from the tide-free system that was applied in ATL03 to photon heights to the ht_water_surf to the mean-tide system. Subtract value from ht_water_surf to reference it in the mean-tide system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_stdev_lseg /gt2r/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_dem_source /gt2r/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int32 0 valid_max Int32 4 contentType String referenceInformation description String Flag equal to the source of the selected photon (in hierarchy of Arctic/Global/MSS/Antarctic). Values: 0=None, 1=Arctic, 2=Global, 3=MSS, 4=Antarctic. coordinates String delta_time segment_lat segment_lon flag_meanings String none arctic global mss antarctic flag_values Int32 0 1 2 3 4 _FillValue Int32 2147483647 long_name String dem source flag segment_fpb_correction /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String First photon bias correction units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String First photon bias correction. May be applied at user disrection by subtracting from mean height produts ht_ortho and ht_water_surf. coordinates String delta_time segment_lat segment_lon segment_azimuth /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Azimuth standard_name String azimuth units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. coordinates String delta_time segment_lat segment_lon inland_water_body_size /gt2r/delta_time _FillValue Int8 127 long_name String Body size units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 0 valid_max Int8 9 contentType String referenceInformation description String Size of Inland Water Body, A=area, where 0=Not_Assigned, 1=A>10,000 sq km, 2=10,000>A>=1,000, 3=1,000>A>=100, 4=100>A>=10, 5=10>A>=1, 6=1>A>=0.1, 7=0.01>A, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String not_assigned area_gt_10000 10000_gt_area_ge_1000 1000_gt_area_ge_100 100_gt_area_ge_10 10_gt_area_ge_1 1_gt_area_ge_0.1 0.01_gt_area Reserved Reserved flag_values Int8 0 1 2 3 4 5 6 7 8 9 met_wind10_atl13 /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height, based on derived water surface wave height. coordinates String delta_time segment_lat segment_lon snow_ice_atl09 /gt2r/delta_time _FillValue Int32 2147483647 long_name String Snow Ice Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) contentType String modelResult description String NOAA snow/ice flag scaled by ATL09 (0=ice-free water, 1=snow-free land, 2=snow, 3=ice, 127=invalid) coordinates String delta_time segment_lat segment_lon flag_meanings String ice_free_water snow_free_land snow ice invalid flag_values Int32 0 1 2 3 127 segment_tide_ocean /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Ocean units String meters source String ATL03 contentType String auxiliaryInformation description String Ocean tides including diurnal and semi-diurnal (harmonic analysis (+-4 m)). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon err_slope_trk /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Slope Error units String 1 source String section 5.3.3 (C) contentType String qualityInformation description String Error included in segment_slope_trk_local. coordinates String delta_time segment_lat segment_lon segment_slope_trk_bdy /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water Body Slope units String m/m source String ATL13 ATBD, Section 5.3.5 (A) contentType String physicalMeasurement description String Along track water body surface slope, reported per short segment ID per water body. coordinates String delta_time segment_lat segment_lon sseg_mean_lat /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Mean latitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon segment_geoid_free2mean /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Geoid Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Value to convert segment geoid heights from the mean-tide system to the tide-free system. Subtract this value from mean-tide system segment_geoid (on ATL13) to get geoid heights in the tide-free system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_spec_width /gt2r/delta_time _FillValue Int8 127 long_name String Spectral width Flag units String 1 source String ATL13 ATBD, Section 4.8.8 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Spectral moments width flag. The flag is set as follows: 0 when spec_width is invalid; 1 when 0 <= spec_width <= 0.2; 2 when 0.2 < spec_width <= 0.3; 3 when 0.3 < spec_width <= 0.4; 4 when 0.4 < spec_width <= 0.5; 5 when 0.5 < spec_width <= 0.6; 6 when 0.6 < spec_width <= 0.7; 7 when 0.7 < spec_width <= 0.8; 8 when 0.8 < spec_width <= 0.9; 9 when 0.9 < spec_width. coordinates String delta_time segment_lat segment_lon flag_meanings String invalid 0<=spec_width<=0.2 0.2<spec_width<=0.3 0.3<spec_width<=0.4 0.4<spec_width<=0.5 0.5<spec_width<=0.6 0.6<spec_width<=0.7 0.7<spec_width<=0.8 0.8<spec_width<=0.9 0.9<spec_width flag_values Int8 0 1 2 3 4 5 6 7 8 9 qf_bckgrd /gt2r/delta_time _FillValue Int8 127 long_name String Background Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 6 contentType String qualityInformation description String Describes the degree of background photons present in each short segment. bckgrd_dnsty_threshold1= 0.001 (counts per bi per Lseg); bckgrd_dnsty_threshold2= 0.01 (counts per bin per Lseg); bckgrd_dnsty_threshold3= 0.05 (counts per bin per Lseg); bckgrd_dnsty_threshold4= 0.1 (counts per bin per Lseg); bckgrd_dnsty_threshold5= 0.3 (counts per bin per Lseg); bckgrd_dnsty_threshold6= 0.5 (counts per bin per Lseg) coordinates String delta_time segment_lat segment_lon flag_meanings String equal_to_or_below_threshold1 equal_to_or_below_threshold2 equal_to_or_below_threshold3 equal_to_or_below_threshold4 equal_to_or_below_threshold5 equal_to_or_below_threshold6 above_threshold6 flag_values Int8 0 1 2 3 4 5 6 sseg_mean_time /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean time standard_name String time units String Seconds since 2018-01-01 source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Mean time of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon met_ts_atl09 /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface temperature standard_name String temperature units String K source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Surface (skin) temperature from ATL09. coordinates String delta_time segment_lat segment_lon segment_bias_em /gt2r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Electromagnetic bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Electromagnetic bias. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon segment_dem_ht /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String DEM Height units String meters source String ATL13 ATBD, Section 5.3.5 contentType String referenceInformation description String DEM height relative to WGS-84 ellipsoid, reported at the short segment rate. coordinates String delta_time segment_lat segment_lon subsurface_backscat_ampltd /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface backscatter amplitude units String 1 source String Section 5.3.4 (A) contentType String modelResult description String Subsurface backscatter amplitude, described in section 4.5.3, reported per long segment (default length = 10 short segments = approximately 1000 signal photons). coordinates String delta_time segment_lat segment_lon segment_dac /gt2r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment DAC units String meters source String ATBD Section 5.3.5A contentType String auxiliaryInformation description String Dynamic atmospheric correction (DAC) includes inverted barometer (IB) effect (+- 5 cm). Although available at short segment rate for all water body types, value is provided mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon DODS_EXTRA Container Unlimited_Dimension String delta_time description String Contains per-beam data products. data_rate String Data within this group are stored at the inland water short segment rate (/ancillary_data/inland_water/s_seg2). atlas_pce String pce2 atlas_beam_type String strong groundtrack_id String gt2r atmosphere_profile String profile_2 atlas_spot_number String 3 sc_orientation String Forward anom_ssegs anom_sseg_time 6476 anom_sseg_lat /gt2r/anom_ssegs/anom_sseg_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of the short segment (mean of signal class >=2 ph Lats). coordinates String anom_sseg_time anom_sseg_lon anom_sseg_time /gt2r/anom_ssegs/anom_sseg_time long_name String Delta Time standard_name String time units String sec source String ATL13 ATBD, Table 5-4b contentType String physicalMeasurement description String Time of the short segment (mean of signal class >=2 ph time). coordinates String anom_sseg_lat anom_sseg_lon anom_sseg_lon /gt2r/anom_ssegs/anom_sseg_time long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of the short segment (mean of signal class >=2 ph Lons). coordinates String anom_sseg_time anom_sseg_lat transect_id /gt2r/anom_ssegs/anom_sseg_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon cycle_number /gt2r/anom_ssegs/anom_sseg_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon rgt /gt2r/anom_ssegs/anom_sseg_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_sig_ph_cnt /gt2r/anom_ssegs/anom_sseg_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_trigger_flag /gt2r/anom_ssegs/anom_sseg_time /ds_anom_trigger _FillValue Int8 127 long_name String Anomalous classification flag units String 1 source String ATL13 ATBD, Table 5-4b valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Nine element array describing justification for short segment classification as anomalous, where for each element 0 = not triggered as anomalous and 1 = triggered as anomalous due to any of the following causes: [element 1=coarse ht difference, element 2=abnormal length, element 3= histogram mode spread, element 4=histogram mode count, element 5=histogram mode intensity, element 6=invalid long segment, element 7=shore buffer designation, element 8=insufficient signal phs, element 9=transect coarse water height unavailable against which to test short segment height] coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon flag_meanings String not_triggered_as_anomalous triggered_as_anomalous flag_values Int8 0 1 anom_sseg_stdev /gt2r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Segment standard deviation units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Standard deviation of anomalous short segment photon height in the anomalous short segment with signal classification >= 2. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_ht_delta /gt2r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Height difference units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height difference between anom_sseg_mode of the anomalous short segment and the transect coarse_transect_ht. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_length /gt2r/anom_ssegs/anom_sseg_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Length of the short segment, based on end points computed by the average of sseg_endpoint_avg_n signal photons. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lon /gt2r/anom_ssegs/anom_sseg_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String End longitude of the anomalous short segment, based on the average longitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon coarse_transect_ht /gt2r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Coarse water height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Coarse water height of transect. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon atl13refid /gt2r/anom_ssegs/anom_sseg_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mode /gt2r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Anomalous mode bin height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height of anomalous short segment as determined by histogram bin mode. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_quality /gt2r/anom_ssegs/anom_sseg_time /ds_sseg_quality long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each anomalous short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon _FillValue Int32 2147483647 anom_sseg_start_lon /gt2r/anom_ssegs/anom_sseg_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Start longitude of the anomalous short segment, based on the average longitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mean_ht_ortho /gt2r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height of anomalous short segment as determined by the mean of photon orthometric heights in the anomalous short segment with signal classification >2 coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_start_lat /gt2r/anom_ssegs/anom_sseg_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Start latitude of the anomalous short segment, based on the average latitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lat /gt2r/anom_ssegs/anom_sseg_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String End latitude of the anomalous short segment, based on the average latitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon DODS_EXTRA Container Unlimited_Dimension String anom_sseg_time description String Contains per-beam anomalous short segment output parameters. gt1l delta_time 9876 segment_lon /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lat /gt1l/delta_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of reporting location for all short segment statistics. coordinates String delta_time segment_lon delta_time /gt1l/delta_time long_name String Delta Time standard_name String time units String seconds since 2018-01-01 source String ATL03 contentType String physicalMeasurement description String Number of GPS seconds since the ATLAS SDP epoch. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. coordinates String segment_lat segment_lon sseg_sig_ph_cnt /gt1l/delta_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String delta_time segment_lat segment_lon sseg_dist_from_eq /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Distance from equator to segment start standard_name String Along-track distance units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Along-track distance from the equator to the first photon in the short segment. coordinates String delta_time segment_lat segment_lon qf_bias_fit /gt1l/delta_time _FillValue Int8 127 long_name String Height Bias Fit Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The height bias fit flag is set based on the value of the goodness of fit bias estimated as the difference between the centroid elevations of the observed surface water histogram and fitted integrated water surface model histogram. The flag values are set as follows: = -3 if H_bias_fit < -0.10 (m); -2 if -0.10 <= H_bias_fit < -0.05;-1 when -0.05 <= H_bias_fit < -0.01; 0 if -0.01 <= H_bias_fit < 0.01 (m); 1 if 0.01 <= H_bias_fit < 0.05; 2 if 0.05 < H_bias_fit < 0.10; 3 if 0.10 <= H_bias_fit; 4 if H_bias_fit is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 equal_to_or_above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 sseg_mean_lon /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Mean longitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon cloud_flag_atm_atl09 /gt1l/delta_time _FillValue Int8 127 long_name String Cloud Flag Atm units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 10 contentType String modelResult description String Cloud flag from backscatter profile. coordinates String delta_time segment_lat segment_lon qf_ice /gt1l/delta_time _FillValue Int8 127 long_name String Ice Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The quality flag for ice describes the likelihood of ice on the short water body surface segment. 0 for QF_Bckgrd<= 2; 1 for 2 < QF_Bckgrd<= 4; 2 for 4 < QF_Bckgrd; 3 for (4 < QF_Bckgrd and QF_Cloud=1) coordinates String delta_time segment_lat segment_lon flag_meanings String qf_bckgrd_le_2 qf_bckgrd_le_4 qf_bckgrd_gt_4 qf_bckgrd_w_cloud flag_values Int8 0 1 2 3 transect_id /gt1l/delta_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String delta_time segment_lat segment_lon inland_water_body_type /gt1l/delta_time _FillValue Int8 127 long_name String Body type units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Type of Inland Water Body, where 1=Lake, 2=Known Reservoir, 3=(Reserved for future use), 4=Ephemeral Water, 5=River, 6=Estuary or Bay, 7=Coastal Water, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String Lake Known_Reservoir Reserved_for_future_use Ephemeral_Water River Estuary_or_Bay Coastal_Water Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 inland_water_body_id /gt1l/delta_time _FillValue Int32 2147483647 long_name String Body ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Identifying signature of an individual inland water body. Each body of water is represented by a unique numeric value. coordinates String delta_time segment_lat segment_lon sseg_end_lon /gt1l/delta_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon qf_subsurface_attenuation /gt1l/delta_time _FillValue Int8 127 long_name String Subsurface attenuation quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface attenuation was constrained during deconvolution by the minimum (initial) limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the subsurface attenuation fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for subsurface attenuation is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 segment_quality /gt1l/delta_time /ds_sseg_quality _FillValue Int32 2147483647 long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String delta_time segment_lat segment_lon segment_geoid /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Geoid units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Applicable mean-tide system geoid value at reporting location for all short segment statistics. (see geoid_free2mean to convert to the tide-free system.) coordinates String delta_time segment_lat segment_lon qf_sseg_length /gt1l/delta_time _FillValue Int8 127 long_name String Short Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Length of short segments flag. The flag is set as follows: 0 if sseg_length < 10 (meters); 1 if 10 <= sseg_length < 20 (meters); 2 if 20 <= sseg_length < 30 (meters); 3 if 30 <= sseg_length < 50 (meters); 4 if 50 <= sseg_length < 75 (meters); 5 if 75 <= sseg_length < 100 (meters); 6 if 100 <= sseg_length < 150 (meters); 7 if 150 <= sseg_length < 200 (meters); 8 if 200 <= sseg_length < 300 (meters); 9 if 300 <= sseg_length. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 below_threshold9 equal_to_or_above_threshold9 flag_values Int8 0 1 2 3 4 5 6 7 8 9 sseg_start_lon /gt1l/delta_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_tide_equilibrium /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Equilibrium units String meters source String ATL03 contentType String auxiliaryInformation description String Long period equilibrium tide self-consistent with ocean tide model (+- 0.04 m). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon qf_lseg_length /gt1l/delta_time _FillValue Int8 127 long_name String Long Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The Long Segment Length flag is set based on the length of the long segment. The flag is set as follows: 0 if Lseg_length < 500 (meters); 1 if 50 <= Lseg_length < 1500 (meters); 2 if 150 <= Lseg_length < 3000 (meters); 3 if 3000 <= Lseg_length coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 above_threshold4 flag_values Int8 0 1 2 3 significant_wave_ht /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String SWH units String meters source String section 5.3.3 (C) contentType String physicalMeasurement description String Significant wave height coordinates String delta_time segment_lat segment_lon bottom_lat /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Bottom latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon cycle_number /gt1l/delta_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String delta_time segment_lat segment_lon qf_subsurface_backscat_ampltd /gt1l/delta_time _FillValue Int8 127 long_name String Subsurface backscatter amplitude quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface backscatter amplitude was constrained during deconvolution by the minimum limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the backscatter amplitude fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for backscatter amplitude is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 water_depth /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water depth units String meters source String ATL13 ATBD, Section 5.3.4 (A) contentType String referenceInformation description String Depth from the mean water surface to detected bottom. coordinates String delta_time segment_lat segment_lon qf_bias_em /gt1l/delta_time _FillValue Int8 127 long_name String EM Bias Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The Electromagnetic Bias flag is set based on threshold checks for the estimated electromagnetic height bias. The flag is set as follows: -3 if H_bias_EM < -0.10 (m); -2 if -0.10 < H_bias_EM < -0.05; -1 if -0.05 <= H_bias_EM < -0.01; 0 if -0.01 <= H_bias_EM < 0.01 (m); 1 if 0.01 <= H_bias_EM < 0.05; 2 if 0.05 <= H_bias_EM < 0.10; 3 if 0.10 < H_bias_EM; 4 if H_bias_EM is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 segment_id_end /gt1l/delta_time long_name String Last ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String Last ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_stdev_vlseg /gt1l/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the very long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_apparent_ht /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Apparent height of the short segment, before adjustments are made by the algorithm, based on an average of heights within a designated range of the short segment mode. coordinates String delta_time segment_lat segment_lon stdev_water_surf /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface StDev units String meters source String section 5.3.3 (C) contentType String referenceInformation description String Derived standard deviation of water surface, calculated over long segments (when available) with result reported at each short segment location tag contained within. coordinates String delta_time segment_lat segment_lon met_wind10_atl09 /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height from ATL09 input. coordinates String delta_time segment_lat segment_lon qf_iwp /gt1l/delta_time _FillValue Int8 127 long_name String Inland Water Segment Processing Flag units String 1 source String Inland Water ATBD valid_min Int8 1 valid_max Int8 7 contentType String qualityInformation description String Describes the level of processing the inland water algorithm was able to perform based on the data available, ranging from one to 7. coordinates String delta_time segment_lat segment_lon flag_meanings String 1_short_segment 2_short_segments 3_to_5_short_segments 6_to_7_short_segments 8_to_9_short_segments 10_to_29_short_segments at_least_30_short_segments flag_values Int8 1 2 3 4 5 6 7 segment_podppd_flag /gt1l/delta_time _FillValue Int8 0 long_name String POD_PPD Flag units String 1 source String ATL02, ANC04, ANC05 valid_min Int8 0 valid_max Int8 7 contentType String referenceInformation description String Composite POD/PPD flag that indicates the quality of input geolocation products for the utilized ATL03 segments on an ATL13 short segment output basis. A non-zero value may indicate that geolocation solutions are degraded or that ATLAS is within a calibration scan period (CAL). The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible non-CAL values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE; possible CAL values are: 4=CAL_NOMINAL; 5=CAL_POD_DEGRADE; 6=CAL_PPD_DEGRADE; 7=CAL_PODPPD_DEGRADE; coordinates String delta_time flag_meanings String nominal pod_degrade ppd_degrade podppd_degrade cal_nominal cal_pod_degrade cal_ppd_degrade cal_podppd_degrade flag_values Int8 0 1 2 3 4 5 6 7 qf_ht_adj /gt1l/delta_time _FillValue Int8 127 long_name String Height adjustment Quality Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (C) valid_min Int8 -4 valid_max Int8 5 contentType String qualityInformation description String Flag representing the range of height, defined in 5.3.5 (C), which has been added to the apparent surface height due to frame of reference scaling during deconvolution analysis. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 equal_to_or_above_threshold8 invalid flag_values Int8 -4 -3 -2 -1 0 1 2 3 4 5 segment_full_sat_fract /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Full Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be fully saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon segment_id_beg /gt1l/delta_time long_name String First ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String First ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_subsurf_anomaly /gt1l/delta_time _FillValue Int8 127 long_name String Subsurface Anomaly Quality Flag units String 1 source String Inland Water ATBD 5.3.4(A) valid_min Int8 1 valid_max Int8 3 contentType String qualityInformation description String Describes the likelihood that the bottom or other subsurface anomaly is bottom based on the threshold value at which an anomaly was found. 1 = Subsurface anomaly due to bottom likely; 2 = Subsurface signal may indicate bottom or other anomaly; 3 = Possible subsurface anomaly; invalid = No subsurface anomaly detected coordinates String delta_time segment_lat segment_lon flag_meanings String bottom_likely bottom_or_other_anomaly possible_subsurface_anomaly flag_values Int8 1 2 3 subsurface_attenuation /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface Attenuation units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Subsurface attenuation coefficient. coordinates String delta_time segment_lat segment_lon layer_flag_atl09 /gt1l/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Consolidated cloud flag. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_region /gt1l/delta_time _FillValue Int32 2147483647 long_name String Body region units String 1 source String ATL13 ATBD, Section 5.3.1 (A) contentType String referenceInformation description String ATL13-created shapefile representing relevant bodies of water over which to implement the ATL13 water surface finding algorithm only within a region of processing interest. coordinates String delta_time segment_lat segment_lon sseg_end_lat /gt1l/delta_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Latitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon cloud_flag_asr_atl09 /gt1l/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 5 contentType String modelResult description String Cloud probability from ASR. coordinates String delta_time segment_lat segment_lon flag_meanings String clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence flag_values Int8 0 1 2 3 4 5 _FillValue Int8 127 long_name String Cloud Flag ASR ice_flag /gt1l/delta_time _FillValue Int8 127 long_name String Ice Flag units String 1 source String ATL13 ATBD, section 5.2 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Describes likelihood of ice on water surface short segment. coordinates String delta_time segment_lat segment_lon flag_meanings String no_ice ice flag_values Int8 0 1 sseg_start_lat /gt1l/delta_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_ref_elev /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String elevation standard_name String elevation units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from east-north plane and positive towards up. coordinates String delta_time segment_lat segment_lon segment_apparent_stdev /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent StDev units String meters source String section 5.3.2 (C) contentType String referenceInformation description String Standard deviation of short segment photon height in the short segment with signal classification >= sig_threshold. coordinates String delta_time segment_lat segment_lon ht_ortho /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height EGM2008 converted from ellipsoidal height. coordinates String delta_time segment_lat segment_lon alpha_mle /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Maximum likelihood alpha units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Alpha calculated by maximum likelihood analysis of the subsurface profile range. coordinates String delta_time segment_lat segment_lon rgt /gt1l/delta_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String delta_time segment_lat segment_lon ht_water_surf /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water surface height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Water surface height, reported for each short segment (default length = approximately 100 signal photons) with reference to WGS84 ellipsoid coordinates String delta_time segment_lat segment_lon segment_near_sat_fract /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Near Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be nearly saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon err_ht_water_surf /gt1l/delta_time units String 1 _FillValue Float32 3.402823466e+38 long_name String Height Error source String section 5.3.3 (C) contentType String qualityInformation description String Error included in heights reported in ht_water_surf. coordinates String delta_time segment_lat segment_lon bottom_lon /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon segment_bias_fit /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Goodness of fit bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Bias contribution from goodness of observation/system response fit. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon atl13refid /gt1l/delta_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id coordinates String delta_time segment_lat segment_lon qf_cloud /gt1l/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL09 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String This flag is a combination of multiple flags (cloud_flag_atm, cloud_flag_asr, and bsnow_con) and takes daytime/nighttime into consideration. A value of 1 means clouds or blowing snow are likely present. A value of 0 indicates the likely absence of clouds or blowing snow. From the ATL09 data closest to the segment time. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_source /gt1l/delta_time _FillValue Int8 127 long_name String Body source units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Source of Inland Water Body shape, where 1=HydroLAKES, 2=Global Lakes and Wetlands Database, 3=Named Marine Water Bodies, 4=GSHHG Shoreline, 5=Global River Widths from Landsat, 6=Reserved, 7=Reserved, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String HydroLAKES Global_Lakes_and_Wetlands_Database Named_Marine_Water_Bodies GSHHG_Shoreline Global_River_Widths_from_Landsat Reserved Reserved Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 sseg_length /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length standard_name String Length units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Distance from the first to the last photon in the short segment. coordinates String delta_time segment_lat segment_lon segment_tide_earth_free2mean /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Earth Tide Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Segment rate value to convert solid earth tide from the tide-free system that was applied in ATL03 to photon heights to the ht_water_surf to the mean-tide system. Subtract value from ht_water_surf to reference it in the mean-tide system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_stdev_lseg /gt1l/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_dem_source /gt1l/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int32 0 valid_max Int32 4 contentType String referenceInformation description String Flag equal to the source of the selected photon (in hierarchy of Arctic/Global/MSS/Antarctic). Values: 0=None, 1=Arctic, 2=Global, 3=MSS, 4=Antarctic. coordinates String delta_time segment_lat segment_lon flag_meanings String none arctic global mss antarctic flag_values Int32 0 1 2 3 4 _FillValue Int32 2147483647 long_name String dem source flag segment_fpb_correction /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String First photon bias correction units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String First photon bias correction. May be applied at user disrection by subtracting from mean height produts ht_ortho and ht_water_surf. coordinates String delta_time segment_lat segment_lon segment_azimuth /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Azimuth standard_name String azimuth units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. coordinates String delta_time segment_lat segment_lon inland_water_body_size /gt1l/delta_time _FillValue Int8 127 long_name String Body size units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 0 valid_max Int8 9 contentType String referenceInformation description String Size of Inland Water Body, A=area, where 0=Not_Assigned, 1=A>10,000 sq km, 2=10,000>A>=1,000, 3=1,000>A>=100, 4=100>A>=10, 5=10>A>=1, 6=1>A>=0.1, 7=0.01>A, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String not_assigned area_gt_10000 10000_gt_area_ge_1000 1000_gt_area_ge_100 100_gt_area_ge_10 10_gt_area_ge_1 1_gt_area_ge_0.1 0.01_gt_area Reserved Reserved flag_values Int8 0 1 2 3 4 5 6 7 8 9 met_wind10_atl13 /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height, based on derived water surface wave height. coordinates String delta_time segment_lat segment_lon snow_ice_atl09 /gt1l/delta_time _FillValue Int32 2147483647 long_name String Snow Ice Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) contentType String modelResult description String NOAA snow/ice flag scaled by ATL09 (0=ice-free water, 1=snow-free land, 2=snow, 3=ice, 127=invalid) coordinates String delta_time segment_lat segment_lon flag_meanings String ice_free_water snow_free_land snow ice invalid flag_values Int32 0 1 2 3 127 segment_tide_ocean /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Ocean units String meters source String ATL03 contentType String auxiliaryInformation description String Ocean tides including diurnal and semi-diurnal (harmonic analysis (+-4 m)). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon err_slope_trk /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Slope Error units String 1 source String section 5.3.3 (C) contentType String qualityInformation description String Error included in segment_slope_trk_local. coordinates String delta_time segment_lat segment_lon segment_slope_trk_bdy /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water Body Slope units String m/m source String ATL13 ATBD, Section 5.3.5 (A) contentType String physicalMeasurement description String Along track water body surface slope, reported per short segment ID per water body. coordinates String delta_time segment_lat segment_lon sseg_mean_lat /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Mean latitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon segment_geoid_free2mean /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Geoid Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Value to convert segment geoid heights from the mean-tide system to the tide-free system. Subtract this value from mean-tide system segment_geoid (on ATL13) to get geoid heights in the tide-free system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_spec_width /gt1l/delta_time _FillValue Int8 127 long_name String Spectral width Flag units String 1 source String ATL13 ATBD, Section 4.8.8 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Spectral moments width flag. The flag is set as follows: 0 when spec_width is invalid; 1 when 0 <= spec_width <= 0.2; 2 when 0.2 < spec_width <= 0.3; 3 when 0.3 < spec_width <= 0.4; 4 when 0.4 < spec_width <= 0.5; 5 when 0.5 < spec_width <= 0.6; 6 when 0.6 < spec_width <= 0.7; 7 when 0.7 < spec_width <= 0.8; 8 when 0.8 < spec_width <= 0.9; 9 when 0.9 < spec_width. coordinates String delta_time segment_lat segment_lon flag_meanings String invalid 0<=spec_width<=0.2 0.2<spec_width<=0.3 0.3<spec_width<=0.4 0.4<spec_width<=0.5 0.5<spec_width<=0.6 0.6<spec_width<=0.7 0.7<spec_width<=0.8 0.8<spec_width<=0.9 0.9<spec_width flag_values Int8 0 1 2 3 4 5 6 7 8 9 qf_bckgrd /gt1l/delta_time _FillValue Int8 127 long_name String Background Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 6 contentType String qualityInformation description String Describes the degree of background photons present in each short segment. bckgrd_dnsty_threshold1= 0.001 (counts per bi per Lseg); bckgrd_dnsty_threshold2= 0.01 (counts per bin per Lseg); bckgrd_dnsty_threshold3= 0.05 (counts per bin per Lseg); bckgrd_dnsty_threshold4= 0.1 (counts per bin per Lseg); bckgrd_dnsty_threshold5= 0.3 (counts per bin per Lseg); bckgrd_dnsty_threshold6= 0.5 (counts per bin per Lseg) coordinates String delta_time segment_lat segment_lon flag_meanings String equal_to_or_below_threshold1 equal_to_or_below_threshold2 equal_to_or_below_threshold3 equal_to_or_below_threshold4 equal_to_or_below_threshold5 equal_to_or_below_threshold6 above_threshold6 flag_values Int8 0 1 2 3 4 5 6 sseg_mean_time /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean time standard_name String time units String Seconds since 2018-01-01 source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Mean time of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon met_ts_atl09 /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface temperature standard_name String temperature units String K source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Surface (skin) temperature from ATL09. coordinates String delta_time segment_lat segment_lon segment_bias_em /gt1l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Electromagnetic bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Electromagnetic bias. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon segment_dem_ht /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String DEM Height units String meters source String ATL13 ATBD, Section 5.3.5 contentType String referenceInformation description String DEM height relative to WGS-84 ellipsoid, reported at the short segment rate. coordinates String delta_time segment_lat segment_lon subsurface_backscat_ampltd /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface backscatter amplitude units String 1 source String Section 5.3.4 (A) contentType String modelResult description String Subsurface backscatter amplitude, described in section 4.5.3, reported per long segment (default length = 10 short segments = approximately 1000 signal photons). coordinates String delta_time segment_lat segment_lon segment_dac /gt1l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment DAC units String meters source String ATBD Section 5.3.5A contentType String auxiliaryInformation description String Dynamic atmospheric correction (DAC) includes inverted barometer (IB) effect (+- 5 cm). Although available at short segment rate for all water body types, value is provided mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon DODS_EXTRA Container Unlimited_Dimension String delta_time description String Contains per-beam data products. data_rate String Data within this group are stored at the inland water short segment rate (/ancillary_data/inland_water/s_seg2). atlas_pce String pce3 atlas_beam_type String weak groundtrack_id String gt1l atmosphere_profile String profile_1 atlas_spot_number String 6 sc_orientation String Forward anom_ssegs anom_sseg_time 2183 anom_sseg_lat /gt1l/anom_ssegs/anom_sseg_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of the short segment (mean of signal class >=2 ph Lats). coordinates String anom_sseg_time anom_sseg_lon anom_sseg_time /gt1l/anom_ssegs/anom_sseg_time long_name String Delta Time standard_name String time units String sec source String ATL13 ATBD, Table 5-4b contentType String physicalMeasurement description String Time of the short segment (mean of signal class >=2 ph time). coordinates String anom_sseg_lat anom_sseg_lon anom_sseg_lon /gt1l/anom_ssegs/anom_sseg_time long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of the short segment (mean of signal class >=2 ph Lons). coordinates String anom_sseg_time anom_sseg_lat transect_id /gt1l/anom_ssegs/anom_sseg_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon cycle_number /gt1l/anom_ssegs/anom_sseg_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon rgt /gt1l/anom_ssegs/anom_sseg_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_sig_ph_cnt /gt1l/anom_ssegs/anom_sseg_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_trigger_flag /gt1l/anom_ssegs/anom_sseg_time /ds_anom_trigger _FillValue Int8 127 long_name String Anomalous classification flag units String 1 source String ATL13 ATBD, Table 5-4b valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Nine element array describing justification for short segment classification as anomalous, where for each element 0 = not triggered as anomalous and 1 = triggered as anomalous due to any of the following causes: [element 1=coarse ht difference, element 2=abnormal length, element 3= histogram mode spread, element 4=histogram mode count, element 5=histogram mode intensity, element 6=invalid long segment, element 7=shore buffer designation, element 8=insufficient signal phs, element 9=transect coarse water height unavailable against which to test short segment height] coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon flag_meanings String not_triggered_as_anomalous triggered_as_anomalous flag_values Int8 0 1 anom_sseg_stdev /gt1l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Segment standard deviation units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Standard deviation of anomalous short segment photon height in the anomalous short segment with signal classification >= 2. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_ht_delta /gt1l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Height difference units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height difference between anom_sseg_mode of the anomalous short segment and the transect coarse_transect_ht. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_length /gt1l/anom_ssegs/anom_sseg_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Length of the short segment, based on end points computed by the average of sseg_endpoint_avg_n signal photons. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lon /gt1l/anom_ssegs/anom_sseg_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String End longitude of the anomalous short segment, based on the average longitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon coarse_transect_ht /gt1l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Coarse water height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Coarse water height of transect. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon atl13refid /gt1l/anom_ssegs/anom_sseg_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mode /gt1l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Anomalous mode bin height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height of anomalous short segment as determined by histogram bin mode. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_quality /gt1l/anom_ssegs/anom_sseg_time /ds_sseg_quality long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each anomalous short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon _FillValue Int32 2147483647 anom_sseg_start_lon /gt1l/anom_ssegs/anom_sseg_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Start longitude of the anomalous short segment, based on the average longitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mean_ht_ortho /gt1l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height of anomalous short segment as determined by the mean of photon orthometric heights in the anomalous short segment with signal classification >2 coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_start_lat /gt1l/anom_ssegs/anom_sseg_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Start latitude of the anomalous short segment, based on the average latitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lat /gt1l/anom_ssegs/anom_sseg_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String End latitude of the anomalous short segment, based on the average latitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon DODS_EXTRA Container Unlimited_Dimension String anom_sseg_time description String Contains per-beam anomalous short segment output parameters. quality_assessment qa_granule_fail_reason 1 long_name String Granule Failure Reason units String 1 source String Operations valid_min Int32 0 valid_max Int32 5 contentType String qualityInformation description String Flag indicating granule failure reason. 0=no failure; 1=processing failure; 2=insufficient data; 3=TBD3; 4=TBD4; 5=TBD5 flag_meanings String no_failure processing_failure insufficient_data TBD3 TBD4 TBD5 flag_values Int32 0 1 2 3 4 5 qa_granule_pass_fail 1 long_name String Granule Pass Flag units String 1 source String Operations valid_min Int32 0 valid_max Int32 1 contentType String qualityInformation description String Flag indicating granule quality. 0=granule passes automatic QA. 1=granule fails automatic QA. flag_meanings String PASS FAIL flag_values Int32 0 1 description String Contains quality assessment data. This may include QA counters, QA along-track data and/or QA summary data. gt3l delta_time 10473 segment_lon /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lat /gt3l/delta_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of reporting location for all short segment statistics. coordinates String delta_time segment_lon delta_time /gt3l/delta_time long_name String Delta Time standard_name String time units String seconds since 2018-01-01 source String ATL03 contentType String physicalMeasurement description String Number of GPS seconds since the ATLAS SDP epoch. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. coordinates String segment_lat segment_lon sseg_sig_ph_cnt /gt3l/delta_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String delta_time segment_lat segment_lon sseg_dist_from_eq /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Distance from equator to segment start standard_name String Along-track distance units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Along-track distance from the equator to the first photon in the short segment. coordinates String delta_time segment_lat segment_lon qf_bias_fit /gt3l/delta_time _FillValue Int8 127 long_name String Height Bias Fit Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The height bias fit flag is set based on the value of the goodness of fit bias estimated as the difference between the centroid elevations of the observed surface water histogram and fitted integrated water surface model histogram. The flag values are set as follows: = -3 if H_bias_fit < -0.10 (m); -2 if -0.10 <= H_bias_fit < -0.05;-1 when -0.05 <= H_bias_fit < -0.01; 0 if -0.01 <= H_bias_fit < 0.01 (m); 1 if 0.01 <= H_bias_fit < 0.05; 2 if 0.05 < H_bias_fit < 0.10; 3 if 0.10 <= H_bias_fit; 4 if H_bias_fit is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 equal_to_or_above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 sseg_mean_lon /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Mean longitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon cloud_flag_atm_atl09 /gt3l/delta_time _FillValue Int8 127 long_name String Cloud Flag Atm units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 10 contentType String modelResult description String Cloud flag from backscatter profile. coordinates String delta_time segment_lat segment_lon qf_ice /gt3l/delta_time _FillValue Int8 127 long_name String Ice Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The quality flag for ice describes the likelihood of ice on the short water body surface segment. 0 for QF_Bckgrd<= 2; 1 for 2 < QF_Bckgrd<= 4; 2 for 4 < QF_Bckgrd; 3 for (4 < QF_Bckgrd and QF_Cloud=1) coordinates String delta_time segment_lat segment_lon flag_meanings String qf_bckgrd_le_2 qf_bckgrd_le_4 qf_bckgrd_gt_4 qf_bckgrd_w_cloud flag_values Int8 0 1 2 3 transect_id /gt3l/delta_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String delta_time segment_lat segment_lon inland_water_body_type /gt3l/delta_time _FillValue Int8 127 long_name String Body type units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Type of Inland Water Body, where 1=Lake, 2=Known Reservoir, 3=(Reserved for future use), 4=Ephemeral Water, 5=River, 6=Estuary or Bay, 7=Coastal Water, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String Lake Known_Reservoir Reserved_for_future_use Ephemeral_Water River Estuary_or_Bay Coastal_Water Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 inland_water_body_id /gt3l/delta_time _FillValue Int32 2147483647 long_name String Body ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Identifying signature of an individual inland water body. Each body of water is represented by a unique numeric value. coordinates String delta_time segment_lat segment_lon sseg_end_lon /gt3l/delta_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon qf_subsurface_attenuation /gt3l/delta_time _FillValue Int8 127 long_name String Subsurface attenuation quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface attenuation was constrained during deconvolution by the minimum (initial) limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the subsurface attenuation fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for subsurface attenuation is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 segment_quality /gt3l/delta_time /ds_sseg_quality _FillValue Int32 2147483647 long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String delta_time segment_lat segment_lon segment_geoid /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Geoid units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Applicable mean-tide system geoid value at reporting location for all short segment statistics. (see geoid_free2mean to convert to the tide-free system.) coordinates String delta_time segment_lat segment_lon qf_sseg_length /gt3l/delta_time _FillValue Int8 127 long_name String Short Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Length of short segments flag. The flag is set as follows: 0 if sseg_length < 10 (meters); 1 if 10 <= sseg_length < 20 (meters); 2 if 20 <= sseg_length < 30 (meters); 3 if 30 <= sseg_length < 50 (meters); 4 if 50 <= sseg_length < 75 (meters); 5 if 75 <= sseg_length < 100 (meters); 6 if 100 <= sseg_length < 150 (meters); 7 if 150 <= sseg_length < 200 (meters); 8 if 200 <= sseg_length < 300 (meters); 9 if 300 <= sseg_length. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 below_threshold9 equal_to_or_above_threshold9 flag_values Int8 0 1 2 3 4 5 6 7 8 9 sseg_start_lon /gt3l/delta_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_tide_equilibrium /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Equilibrium units String meters source String ATL03 contentType String auxiliaryInformation description String Long period equilibrium tide self-consistent with ocean tide model (+- 0.04 m). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon qf_lseg_length /gt3l/delta_time _FillValue Int8 127 long_name String Long Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The Long Segment Length flag is set based on the length of the long segment. The flag is set as follows: 0 if Lseg_length < 500 (meters); 1 if 50 <= Lseg_length < 1500 (meters); 2 if 150 <= Lseg_length < 3000 (meters); 3 if 3000 <= Lseg_length coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 above_threshold4 flag_values Int8 0 1 2 3 significant_wave_ht /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String SWH units String meters source String section 5.3.3 (C) contentType String physicalMeasurement description String Significant wave height coordinates String delta_time segment_lat segment_lon bottom_lat /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Bottom latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon cycle_number /gt3l/delta_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String delta_time segment_lat segment_lon qf_subsurface_backscat_ampltd /gt3l/delta_time _FillValue Int8 127 long_name String Subsurface backscatter amplitude quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface backscatter amplitude was constrained during deconvolution by the minimum limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the backscatter amplitude fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for backscatter amplitude is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 water_depth /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water depth units String meters source String ATL13 ATBD, Section 5.3.4 (A) contentType String referenceInformation description String Depth from the mean water surface to detected bottom. coordinates String delta_time segment_lat segment_lon qf_bias_em /gt3l/delta_time _FillValue Int8 127 long_name String EM Bias Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The Electromagnetic Bias flag is set based on threshold checks for the estimated electromagnetic height bias. The flag is set as follows: -3 if H_bias_EM < -0.10 (m); -2 if -0.10 < H_bias_EM < -0.05; -1 if -0.05 <= H_bias_EM < -0.01; 0 if -0.01 <= H_bias_EM < 0.01 (m); 1 if 0.01 <= H_bias_EM < 0.05; 2 if 0.05 <= H_bias_EM < 0.10; 3 if 0.10 < H_bias_EM; 4 if H_bias_EM is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 segment_id_end /gt3l/delta_time long_name String Last ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String Last ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_stdev_vlseg /gt3l/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the very long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_apparent_ht /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Apparent height of the short segment, before adjustments are made by the algorithm, based on an average of heights within a designated range of the short segment mode. coordinates String delta_time segment_lat segment_lon stdev_water_surf /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface StDev units String meters source String section 5.3.3 (C) contentType String referenceInformation description String Derived standard deviation of water surface, calculated over long segments (when available) with result reported at each short segment location tag contained within. coordinates String delta_time segment_lat segment_lon met_wind10_atl09 /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height from ATL09 input. coordinates String delta_time segment_lat segment_lon qf_iwp /gt3l/delta_time _FillValue Int8 127 long_name String Inland Water Segment Processing Flag units String 1 source String Inland Water ATBD valid_min Int8 1 valid_max Int8 7 contentType String qualityInformation description String Describes the level of processing the inland water algorithm was able to perform based on the data available, ranging from one to 7. coordinates String delta_time segment_lat segment_lon flag_meanings String 1_short_segment 2_short_segments 3_to_5_short_segments 6_to_7_short_segments 8_to_9_short_segments 10_to_29_short_segments at_least_30_short_segments flag_values Int8 1 2 3 4 5 6 7 segment_podppd_flag /gt3l/delta_time _FillValue Int8 0 long_name String POD_PPD Flag units String 1 source String ATL02, ANC04, ANC05 valid_min Int8 0 valid_max Int8 7 contentType String referenceInformation description String Composite POD/PPD flag that indicates the quality of input geolocation products for the utilized ATL03 segments on an ATL13 short segment output basis. A non-zero value may indicate that geolocation solutions are degraded or that ATLAS is within a calibration scan period (CAL). The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible non-CAL values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE; possible CAL values are: 4=CAL_NOMINAL; 5=CAL_POD_DEGRADE; 6=CAL_PPD_DEGRADE; 7=CAL_PODPPD_DEGRADE; coordinates String delta_time flag_meanings String nominal pod_degrade ppd_degrade podppd_degrade cal_nominal cal_pod_degrade cal_ppd_degrade cal_podppd_degrade flag_values Int8 0 1 2 3 4 5 6 7 qf_ht_adj /gt3l/delta_time _FillValue Int8 127 long_name String Height adjustment Quality Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (C) valid_min Int8 -4 valid_max Int8 5 contentType String qualityInformation description String Flag representing the range of height, defined in 5.3.5 (C), which has been added to the apparent surface height due to frame of reference scaling during deconvolution analysis. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 equal_to_or_above_threshold8 invalid flag_values Int8 -4 -3 -2 -1 0 1 2 3 4 5 segment_full_sat_fract /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Full Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be fully saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon segment_id_beg /gt3l/delta_time long_name String First ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String First ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_subsurf_anomaly /gt3l/delta_time _FillValue Int8 127 long_name String Subsurface Anomaly Quality Flag units String 1 source String Inland Water ATBD 5.3.4(A) valid_min Int8 1 valid_max Int8 3 contentType String qualityInformation description String Describes the likelihood that the bottom or other subsurface anomaly is bottom based on the threshold value at which an anomaly was found. 1 = Subsurface anomaly due to bottom likely; 2 = Subsurface signal may indicate bottom or other anomaly; 3 = Possible subsurface anomaly; invalid = No subsurface anomaly detected coordinates String delta_time segment_lat segment_lon flag_meanings String bottom_likely bottom_or_other_anomaly possible_subsurface_anomaly flag_values Int8 1 2 3 subsurface_attenuation /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface Attenuation units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Subsurface attenuation coefficient. coordinates String delta_time segment_lat segment_lon layer_flag_atl09 /gt3l/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Consolidated cloud flag. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_region /gt3l/delta_time _FillValue Int32 2147483647 long_name String Body region units String 1 source String ATL13 ATBD, Section 5.3.1 (A) contentType String referenceInformation description String ATL13-created shapefile representing relevant bodies of water over which to implement the ATL13 water surface finding algorithm only within a region of processing interest. coordinates String delta_time segment_lat segment_lon sseg_end_lat /gt3l/delta_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Latitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon cloud_flag_asr_atl09 /gt3l/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 5 contentType String modelResult description String Cloud probability from ASR. coordinates String delta_time segment_lat segment_lon flag_meanings String clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence flag_values Int8 0 1 2 3 4 5 _FillValue Int8 127 long_name String Cloud Flag ASR ice_flag /gt3l/delta_time _FillValue Int8 127 long_name String Ice Flag units String 1 source String ATL13 ATBD, section 5.2 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Describes likelihood of ice on water surface short segment. coordinates String delta_time segment_lat segment_lon flag_meanings String no_ice ice flag_values Int8 0 1 sseg_start_lat /gt3l/delta_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_ref_elev /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String elevation standard_name String elevation units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from east-north plane and positive towards up. coordinates String delta_time segment_lat segment_lon segment_apparent_stdev /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent StDev units String meters source String section 5.3.2 (C) contentType String referenceInformation description String Standard deviation of short segment photon height in the short segment with signal classification >= sig_threshold. coordinates String delta_time segment_lat segment_lon ht_ortho /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height EGM2008 converted from ellipsoidal height. coordinates String delta_time segment_lat segment_lon alpha_mle /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Maximum likelihood alpha units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Alpha calculated by maximum likelihood analysis of the subsurface profile range. coordinates String delta_time segment_lat segment_lon rgt /gt3l/delta_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String delta_time segment_lat segment_lon ht_water_surf /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water surface height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Water surface height, reported for each short segment (default length = approximately 100 signal photons) with reference to WGS84 ellipsoid coordinates String delta_time segment_lat segment_lon segment_near_sat_fract /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Near Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be nearly saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon err_ht_water_surf /gt3l/delta_time units String 1 _FillValue Float32 3.402823466e+38 long_name String Height Error source String section 5.3.3 (C) contentType String qualityInformation description String Error included in heights reported in ht_water_surf. coordinates String delta_time segment_lat segment_lon bottom_lon /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon segment_bias_fit /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Goodness of fit bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Bias contribution from goodness of observation/system response fit. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon atl13refid /gt3l/delta_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id coordinates String delta_time segment_lat segment_lon qf_cloud /gt3l/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL09 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String This flag is a combination of multiple flags (cloud_flag_atm, cloud_flag_asr, and bsnow_con) and takes daytime/nighttime into consideration. A value of 1 means clouds or blowing snow are likely present. A value of 0 indicates the likely absence of clouds or blowing snow. From the ATL09 data closest to the segment time. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_source /gt3l/delta_time _FillValue Int8 127 long_name String Body source units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Source of Inland Water Body shape, where 1=HydroLAKES, 2=Global Lakes and Wetlands Database, 3=Named Marine Water Bodies, 4=GSHHG Shoreline, 5=Global River Widths from Landsat, 6=Reserved, 7=Reserved, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String HydroLAKES Global_Lakes_and_Wetlands_Database Named_Marine_Water_Bodies GSHHG_Shoreline Global_River_Widths_from_Landsat Reserved Reserved Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 sseg_length /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length standard_name String Length units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Distance from the first to the last photon in the short segment. coordinates String delta_time segment_lat segment_lon segment_tide_earth_free2mean /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Earth Tide Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Segment rate value to convert solid earth tide from the tide-free system that was applied in ATL03 to photon heights to the ht_water_surf to the mean-tide system. Subtract value from ht_water_surf to reference it in the mean-tide system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_stdev_lseg /gt3l/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_dem_source /gt3l/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int32 0 valid_max Int32 4 contentType String referenceInformation description String Flag equal to the source of the selected photon (in hierarchy of Arctic/Global/MSS/Antarctic). Values: 0=None, 1=Arctic, 2=Global, 3=MSS, 4=Antarctic. coordinates String delta_time segment_lat segment_lon flag_meanings String none arctic global mss antarctic flag_values Int32 0 1 2 3 4 _FillValue Int32 2147483647 long_name String dem source flag segment_fpb_correction /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String First photon bias correction units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String First photon bias correction. May be applied at user disrection by subtracting from mean height produts ht_ortho and ht_water_surf. coordinates String delta_time segment_lat segment_lon segment_azimuth /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Azimuth standard_name String azimuth units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. coordinates String delta_time segment_lat segment_lon inland_water_body_size /gt3l/delta_time _FillValue Int8 127 long_name String Body size units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 0 valid_max Int8 9 contentType String referenceInformation description String Size of Inland Water Body, A=area, where 0=Not_Assigned, 1=A>10,000 sq km, 2=10,000>A>=1,000, 3=1,000>A>=100, 4=100>A>=10, 5=10>A>=1, 6=1>A>=0.1, 7=0.01>A, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String not_assigned area_gt_10000 10000_gt_area_ge_1000 1000_gt_area_ge_100 100_gt_area_ge_10 10_gt_area_ge_1 1_gt_area_ge_0.1 0.01_gt_area Reserved Reserved flag_values Int8 0 1 2 3 4 5 6 7 8 9 met_wind10_atl13 /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height, based on derived water surface wave height. coordinates String delta_time segment_lat segment_lon snow_ice_atl09 /gt3l/delta_time _FillValue Int32 2147483647 long_name String Snow Ice Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) contentType String modelResult description String NOAA snow/ice flag scaled by ATL09 (0=ice-free water, 1=snow-free land, 2=snow, 3=ice, 127=invalid) coordinates String delta_time segment_lat segment_lon flag_meanings String ice_free_water snow_free_land snow ice invalid flag_values Int32 0 1 2 3 127 segment_tide_ocean /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Ocean units String meters source String ATL03 contentType String auxiliaryInformation description String Ocean tides including diurnal and semi-diurnal (harmonic analysis (+-4 m)). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon err_slope_trk /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Slope Error units String 1 source String section 5.3.3 (C) contentType String qualityInformation description String Error included in segment_slope_trk_local. coordinates String delta_time segment_lat segment_lon segment_slope_trk_bdy /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water Body Slope units String m/m source String ATL13 ATBD, Section 5.3.5 (A) contentType String physicalMeasurement description String Along track water body surface slope, reported per short segment ID per water body. coordinates String delta_time segment_lat segment_lon sseg_mean_lat /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Mean latitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon segment_geoid_free2mean /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Geoid Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Value to convert segment geoid heights from the mean-tide system to the tide-free system. Subtract this value from mean-tide system segment_geoid (on ATL13) to get geoid heights in the tide-free system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_spec_width /gt3l/delta_time _FillValue Int8 127 long_name String Spectral width Flag units String 1 source String ATL13 ATBD, Section 4.8.8 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Spectral moments width flag. The flag is set as follows: 0 when spec_width is invalid; 1 when 0 <= spec_width <= 0.2; 2 when 0.2 < spec_width <= 0.3; 3 when 0.3 < spec_width <= 0.4; 4 when 0.4 < spec_width <= 0.5; 5 when 0.5 < spec_width <= 0.6; 6 when 0.6 < spec_width <= 0.7; 7 when 0.7 < spec_width <= 0.8; 8 when 0.8 < spec_width <= 0.9; 9 when 0.9 < spec_width. coordinates String delta_time segment_lat segment_lon flag_meanings String invalid 0<=spec_width<=0.2 0.2<spec_width<=0.3 0.3<spec_width<=0.4 0.4<spec_width<=0.5 0.5<spec_width<=0.6 0.6<spec_width<=0.7 0.7<spec_width<=0.8 0.8<spec_width<=0.9 0.9<spec_width flag_values Int8 0 1 2 3 4 5 6 7 8 9 qf_bckgrd /gt3l/delta_time _FillValue Int8 127 long_name String Background Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 6 contentType String qualityInformation description String Describes the degree of background photons present in each short segment. bckgrd_dnsty_threshold1= 0.001 (counts per bi per Lseg); bckgrd_dnsty_threshold2= 0.01 (counts per bin per Lseg); bckgrd_dnsty_threshold3= 0.05 (counts per bin per Lseg); bckgrd_dnsty_threshold4= 0.1 (counts per bin per Lseg); bckgrd_dnsty_threshold5= 0.3 (counts per bin per Lseg); bckgrd_dnsty_threshold6= 0.5 (counts per bin per Lseg) coordinates String delta_time segment_lat segment_lon flag_meanings String equal_to_or_below_threshold1 equal_to_or_below_threshold2 equal_to_or_below_threshold3 equal_to_or_below_threshold4 equal_to_or_below_threshold5 equal_to_or_below_threshold6 above_threshold6 flag_values Int8 0 1 2 3 4 5 6 sseg_mean_time /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean time standard_name String time units String Seconds since 2018-01-01 source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Mean time of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon met_ts_atl09 /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface temperature standard_name String temperature units String K source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Surface (skin) temperature from ATL09. coordinates String delta_time segment_lat segment_lon segment_bias_em /gt3l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Electromagnetic bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Electromagnetic bias. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon segment_dem_ht /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String DEM Height units String meters source String ATL13 ATBD, Section 5.3.5 contentType String referenceInformation description String DEM height relative to WGS-84 ellipsoid, reported at the short segment rate. coordinates String delta_time segment_lat segment_lon subsurface_backscat_ampltd /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface backscatter amplitude units String 1 source String Section 5.3.4 (A) contentType String modelResult description String Subsurface backscatter amplitude, described in section 4.5.3, reported per long segment (default length = 10 short segments = approximately 1000 signal photons). coordinates String delta_time segment_lat segment_lon segment_dac /gt3l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment DAC units String meters source String ATBD Section 5.3.5A contentType String auxiliaryInformation description String Dynamic atmospheric correction (DAC) includes inverted barometer (IB) effect (+- 5 cm). Although available at short segment rate for all water body types, value is provided mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon DODS_EXTRA Container Unlimited_Dimension String delta_time description String Contains per-beam data products. data_rate String Data within this group are stored at the inland water short segment rate (/ancillary_data/inland_water/s_seg2). atlas_pce String pce1 atlas_beam_type String weak groundtrack_id String gt3l atmosphere_profile String profile_3 atlas_spot_number String 2 sc_orientation String Forward anom_ssegs anom_sseg_time 2339 anom_sseg_lat /gt3l/anom_ssegs/anom_sseg_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of the short segment (mean of signal class >=2 ph Lats). coordinates String anom_sseg_time anom_sseg_lon anom_sseg_time /gt3l/anom_ssegs/anom_sseg_time long_name String Delta Time standard_name String time units String sec source String ATL13 ATBD, Table 5-4b contentType String physicalMeasurement description String Time of the short segment (mean of signal class >=2 ph time). coordinates String anom_sseg_lat anom_sseg_lon anom_sseg_lon /gt3l/anom_ssegs/anom_sseg_time long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of the short segment (mean of signal class >=2 ph Lons). coordinates String anom_sseg_time anom_sseg_lat transect_id /gt3l/anom_ssegs/anom_sseg_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon cycle_number /gt3l/anom_ssegs/anom_sseg_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon rgt /gt3l/anom_ssegs/anom_sseg_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_sig_ph_cnt /gt3l/anom_ssegs/anom_sseg_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_trigger_flag /gt3l/anom_ssegs/anom_sseg_time /ds_anom_trigger _FillValue Int8 127 long_name String Anomalous classification flag units String 1 source String ATL13 ATBD, Table 5-4b valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Nine element array describing justification for short segment classification as anomalous, where for each element 0 = not triggered as anomalous and 1 = triggered as anomalous due to any of the following causes: [element 1=coarse ht difference, element 2=abnormal length, element 3= histogram mode spread, element 4=histogram mode count, element 5=histogram mode intensity, element 6=invalid long segment, element 7=shore buffer designation, element 8=insufficient signal phs, element 9=transect coarse water height unavailable against which to test short segment height] coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon flag_meanings String not_triggered_as_anomalous triggered_as_anomalous flag_values Int8 0 1 anom_sseg_stdev /gt3l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Segment standard deviation units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Standard deviation of anomalous short segment photon height in the anomalous short segment with signal classification >= 2. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_ht_delta /gt3l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Height difference units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height difference between anom_sseg_mode of the anomalous short segment and the transect coarse_transect_ht. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_length /gt3l/anom_ssegs/anom_sseg_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Length of the short segment, based on end points computed by the average of sseg_endpoint_avg_n signal photons. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lon /gt3l/anom_ssegs/anom_sseg_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String End longitude of the anomalous short segment, based on the average longitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon coarse_transect_ht /gt3l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Coarse water height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Coarse water height of transect. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon atl13refid /gt3l/anom_ssegs/anom_sseg_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mode /gt3l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Anomalous mode bin height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height of anomalous short segment as determined by histogram bin mode. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_quality /gt3l/anom_ssegs/anom_sseg_time /ds_sseg_quality long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each anomalous short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon _FillValue Int32 2147483647 anom_sseg_start_lon /gt3l/anom_ssegs/anom_sseg_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Start longitude of the anomalous short segment, based on the average longitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mean_ht_ortho /gt3l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height of anomalous short segment as determined by the mean of photon orthometric heights in the anomalous short segment with signal classification >2 coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_start_lat /gt3l/anom_ssegs/anom_sseg_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Start latitude of the anomalous short segment, based on the average latitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lat /gt3l/anom_ssegs/anom_sseg_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String End latitude of the anomalous short segment, based on the average latitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon DODS_EXTRA Container Unlimited_Dimension String anom_sseg_time description String Contains per-beam anomalous short segment output parameters. gt2l delta_time 9827 segment_lon /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lat /gt2l/delta_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of reporting location for all short segment statistics. coordinates String delta_time segment_lon delta_time /gt2l/delta_time long_name String Delta Time standard_name String time units String seconds since 2018-01-01 source String ATL03 contentType String physicalMeasurement description String Number of GPS seconds since the ATLAS SDP epoch. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. coordinates String segment_lat segment_lon sseg_sig_ph_cnt /gt2l/delta_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String delta_time segment_lat segment_lon sseg_dist_from_eq /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Distance from equator to segment start standard_name String Along-track distance units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Along-track distance from the equator to the first photon in the short segment. coordinates String delta_time segment_lat segment_lon qf_bias_fit /gt2l/delta_time _FillValue Int8 127 long_name String Height Bias Fit Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The height bias fit flag is set based on the value of the goodness of fit bias estimated as the difference between the centroid elevations of the observed surface water histogram and fitted integrated water surface model histogram. The flag values are set as follows: = -3 if H_bias_fit < -0.10 (m); -2 if -0.10 <= H_bias_fit < -0.05;-1 when -0.05 <= H_bias_fit < -0.01; 0 if -0.01 <= H_bias_fit < 0.01 (m); 1 if 0.01 <= H_bias_fit < 0.05; 2 if 0.05 < H_bias_fit < 0.10; 3 if 0.10 <= H_bias_fit; 4 if H_bias_fit is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 equal_to_or_above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 sseg_mean_lon /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Mean longitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon cloud_flag_atm_atl09 /gt2l/delta_time _FillValue Int8 127 long_name String Cloud Flag Atm units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 10 contentType String modelResult description String Cloud flag from backscatter profile. coordinates String delta_time segment_lat segment_lon qf_ice /gt2l/delta_time _FillValue Int8 127 long_name String Ice Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The quality flag for ice describes the likelihood of ice on the short water body surface segment. 0 for QF_Bckgrd<= 2; 1 for 2 < QF_Bckgrd<= 4; 2 for 4 < QF_Bckgrd; 3 for (4 < QF_Bckgrd and QF_Cloud=1) coordinates String delta_time segment_lat segment_lon flag_meanings String qf_bckgrd_le_2 qf_bckgrd_le_4 qf_bckgrd_gt_4 qf_bckgrd_w_cloud flag_values Int8 0 1 2 3 transect_id /gt2l/delta_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String delta_time segment_lat segment_lon inland_water_body_type /gt2l/delta_time _FillValue Int8 127 long_name String Body type units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Type of Inland Water Body, where 1=Lake, 2=Known Reservoir, 3=(Reserved for future use), 4=Ephemeral Water, 5=River, 6=Estuary or Bay, 7=Coastal Water, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String Lake Known_Reservoir Reserved_for_future_use Ephemeral_Water River Estuary_or_Bay Coastal_Water Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 inland_water_body_id /gt2l/delta_time _FillValue Int32 2147483647 long_name String Body ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Identifying signature of an individual inland water body. Each body of water is represented by a unique numeric value. coordinates String delta_time segment_lat segment_lon sseg_end_lon /gt2l/delta_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon qf_subsurface_attenuation /gt2l/delta_time _FillValue Int8 127 long_name String Subsurface attenuation quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface attenuation was constrained during deconvolution by the minimum (initial) limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the subsurface attenuation fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for subsurface attenuation is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 segment_quality /gt2l/delta_time /ds_sseg_quality _FillValue Int32 2147483647 long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String delta_time segment_lat segment_lon segment_geoid /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Geoid units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Applicable mean-tide system geoid value at reporting location for all short segment statistics. (see geoid_free2mean to convert to the tide-free system.) coordinates String delta_time segment_lat segment_lon qf_sseg_length /gt2l/delta_time _FillValue Int8 127 long_name String Short Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Length of short segments flag. The flag is set as follows: 0 if sseg_length < 10 (meters); 1 if 10 <= sseg_length < 20 (meters); 2 if 20 <= sseg_length < 30 (meters); 3 if 30 <= sseg_length < 50 (meters); 4 if 50 <= sseg_length < 75 (meters); 5 if 75 <= sseg_length < 100 (meters); 6 if 100 <= sseg_length < 150 (meters); 7 if 150 <= sseg_length < 200 (meters); 8 if 200 <= sseg_length < 300 (meters); 9 if 300 <= sseg_length. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 below_threshold9 equal_to_or_above_threshold9 flag_values Int8 0 1 2 3 4 5 6 7 8 9 sseg_start_lon /gt2l/delta_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_tide_equilibrium /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Equilibrium units String meters source String ATL03 contentType String auxiliaryInformation description String Long period equilibrium tide self-consistent with ocean tide model (+- 0.04 m). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon qf_lseg_length /gt2l/delta_time _FillValue Int8 127 long_name String Long Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The Long Segment Length flag is set based on the length of the long segment. The flag is set as follows: 0 if Lseg_length < 500 (meters); 1 if 50 <= Lseg_length < 1500 (meters); 2 if 150 <= Lseg_length < 3000 (meters); 3 if 3000 <= Lseg_length coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 above_threshold4 flag_values Int8 0 1 2 3 significant_wave_ht /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String SWH units String meters source String section 5.3.3 (C) contentType String physicalMeasurement description String Significant wave height coordinates String delta_time segment_lat segment_lon bottom_lat /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Bottom latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon cycle_number /gt2l/delta_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String delta_time segment_lat segment_lon qf_subsurface_backscat_ampltd /gt2l/delta_time _FillValue Int8 127 long_name String Subsurface backscatter amplitude quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface backscatter amplitude was constrained during deconvolution by the minimum limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the backscatter amplitude fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for backscatter amplitude is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 water_depth /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water depth units String meters source String ATL13 ATBD, Section 5.3.4 (A) contentType String referenceInformation description String Depth from the mean water surface to detected bottom. coordinates String delta_time segment_lat segment_lon qf_bias_em /gt2l/delta_time _FillValue Int8 127 long_name String EM Bias Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The Electromagnetic Bias flag is set based on threshold checks for the estimated electromagnetic height bias. The flag is set as follows: -3 if H_bias_EM < -0.10 (m); -2 if -0.10 < H_bias_EM < -0.05; -1 if -0.05 <= H_bias_EM < -0.01; 0 if -0.01 <= H_bias_EM < 0.01 (m); 1 if 0.01 <= H_bias_EM < 0.05; 2 if 0.05 <= H_bias_EM < 0.10; 3 if 0.10 < H_bias_EM; 4 if H_bias_EM is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 segment_id_end /gt2l/delta_time long_name String Last ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String Last ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_stdev_vlseg /gt2l/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the very long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_apparent_ht /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Apparent height of the short segment, before adjustments are made by the algorithm, based on an average of heights within a designated range of the short segment mode. coordinates String delta_time segment_lat segment_lon stdev_water_surf /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface StDev units String meters source String section 5.3.3 (C) contentType String referenceInformation description String Derived standard deviation of water surface, calculated over long segments (when available) with result reported at each short segment location tag contained within. coordinates String delta_time segment_lat segment_lon met_wind10_atl09 /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height from ATL09 input. coordinates String delta_time segment_lat segment_lon qf_iwp /gt2l/delta_time _FillValue Int8 127 long_name String Inland Water Segment Processing Flag units String 1 source String Inland Water ATBD valid_min Int8 1 valid_max Int8 7 contentType String qualityInformation description String Describes the level of processing the inland water algorithm was able to perform based on the data available, ranging from one to 7. coordinates String delta_time segment_lat segment_lon flag_meanings String 1_short_segment 2_short_segments 3_to_5_short_segments 6_to_7_short_segments 8_to_9_short_segments 10_to_29_short_segments at_least_30_short_segments flag_values Int8 1 2 3 4 5 6 7 segment_podppd_flag /gt2l/delta_time _FillValue Int8 0 long_name String POD_PPD Flag units String 1 source String ATL02, ANC04, ANC05 valid_min Int8 0 valid_max Int8 7 contentType String referenceInformation description String Composite POD/PPD flag that indicates the quality of input geolocation products for the utilized ATL03 segments on an ATL13 short segment output basis. A non-zero value may indicate that geolocation solutions are degraded or that ATLAS is within a calibration scan period (CAL). The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible non-CAL values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE; possible CAL values are: 4=CAL_NOMINAL; 5=CAL_POD_DEGRADE; 6=CAL_PPD_DEGRADE; 7=CAL_PODPPD_DEGRADE; coordinates String delta_time flag_meanings String nominal pod_degrade ppd_degrade podppd_degrade cal_nominal cal_pod_degrade cal_ppd_degrade cal_podppd_degrade flag_values Int8 0 1 2 3 4 5 6 7 qf_ht_adj /gt2l/delta_time _FillValue Int8 127 long_name String Height adjustment Quality Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (C) valid_min Int8 -4 valid_max Int8 5 contentType String qualityInformation description String Flag representing the range of height, defined in 5.3.5 (C), which has been added to the apparent surface height due to frame of reference scaling during deconvolution analysis. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 equal_to_or_above_threshold8 invalid flag_values Int8 -4 -3 -2 -1 0 1 2 3 4 5 segment_full_sat_fract /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Full Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be fully saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon segment_id_beg /gt2l/delta_time long_name String First ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String First ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_subsurf_anomaly /gt2l/delta_time _FillValue Int8 127 long_name String Subsurface Anomaly Quality Flag units String 1 source String Inland Water ATBD 5.3.4(A) valid_min Int8 1 valid_max Int8 3 contentType String qualityInformation description String Describes the likelihood that the bottom or other subsurface anomaly is bottom based on the threshold value at which an anomaly was found. 1 = Subsurface anomaly due to bottom likely; 2 = Subsurface signal may indicate bottom or other anomaly; 3 = Possible subsurface anomaly; invalid = No subsurface anomaly detected coordinates String delta_time segment_lat segment_lon flag_meanings String bottom_likely bottom_or_other_anomaly possible_subsurface_anomaly flag_values Int8 1 2 3 subsurface_attenuation /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface Attenuation units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Subsurface attenuation coefficient. coordinates String delta_time segment_lat segment_lon layer_flag_atl09 /gt2l/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Consolidated cloud flag. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_region /gt2l/delta_time _FillValue Int32 2147483647 long_name String Body region units String 1 source String ATL13 ATBD, Section 5.3.1 (A) contentType String referenceInformation description String ATL13-created shapefile representing relevant bodies of water over which to implement the ATL13 water surface finding algorithm only within a region of processing interest. coordinates String delta_time segment_lat segment_lon sseg_end_lat /gt2l/delta_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Latitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon cloud_flag_asr_atl09 /gt2l/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 5 contentType String modelResult description String Cloud probability from ASR. coordinates String delta_time segment_lat segment_lon flag_meanings String clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence flag_values Int8 0 1 2 3 4 5 _FillValue Int8 127 long_name String Cloud Flag ASR ice_flag /gt2l/delta_time _FillValue Int8 127 long_name String Ice Flag units String 1 source String ATL13 ATBD, section 5.2 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Describes likelihood of ice on water surface short segment. coordinates String delta_time segment_lat segment_lon flag_meanings String no_ice ice flag_values Int8 0 1 sseg_start_lat /gt2l/delta_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_ref_elev /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String elevation standard_name String elevation units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from east-north plane and positive towards up. coordinates String delta_time segment_lat segment_lon segment_apparent_stdev /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent StDev units String meters source String section 5.3.2 (C) contentType String referenceInformation description String Standard deviation of short segment photon height in the short segment with signal classification >= sig_threshold. coordinates String delta_time segment_lat segment_lon ht_ortho /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height EGM2008 converted from ellipsoidal height. coordinates String delta_time segment_lat segment_lon alpha_mle /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Maximum likelihood alpha units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Alpha calculated by maximum likelihood analysis of the subsurface profile range. coordinates String delta_time segment_lat segment_lon rgt /gt2l/delta_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String delta_time segment_lat segment_lon ht_water_surf /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water surface height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Water surface height, reported for each short segment (default length = approximately 100 signal photons) with reference to WGS84 ellipsoid coordinates String delta_time segment_lat segment_lon segment_near_sat_fract /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Near Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be nearly saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon err_ht_water_surf /gt2l/delta_time units String 1 _FillValue Float32 3.402823466e+38 long_name String Height Error source String section 5.3.3 (C) contentType String qualityInformation description String Error included in heights reported in ht_water_surf. coordinates String delta_time segment_lat segment_lon bottom_lon /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon segment_bias_fit /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Goodness of fit bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Bias contribution from goodness of observation/system response fit. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon atl13refid /gt2l/delta_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id coordinates String delta_time segment_lat segment_lon qf_cloud /gt2l/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL09 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String This flag is a combination of multiple flags (cloud_flag_atm, cloud_flag_asr, and bsnow_con) and takes daytime/nighttime into consideration. A value of 1 means clouds or blowing snow are likely present. A value of 0 indicates the likely absence of clouds or blowing snow. From the ATL09 data closest to the segment time. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_source /gt2l/delta_time _FillValue Int8 127 long_name String Body source units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Source of Inland Water Body shape, where 1=HydroLAKES, 2=Global Lakes and Wetlands Database, 3=Named Marine Water Bodies, 4=GSHHG Shoreline, 5=Global River Widths from Landsat, 6=Reserved, 7=Reserved, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String HydroLAKES Global_Lakes_and_Wetlands_Database Named_Marine_Water_Bodies GSHHG_Shoreline Global_River_Widths_from_Landsat Reserved Reserved Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 sseg_length /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length standard_name String Length units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Distance from the first to the last photon in the short segment. coordinates String delta_time segment_lat segment_lon segment_tide_earth_free2mean /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Earth Tide Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Segment rate value to convert solid earth tide from the tide-free system that was applied in ATL03 to photon heights to the ht_water_surf to the mean-tide system. Subtract value from ht_water_surf to reference it in the mean-tide system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_stdev_lseg /gt2l/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_dem_source /gt2l/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int32 0 valid_max Int32 4 contentType String referenceInformation description String Flag equal to the source of the selected photon (in hierarchy of Arctic/Global/MSS/Antarctic). Values: 0=None, 1=Arctic, 2=Global, 3=MSS, 4=Antarctic. coordinates String delta_time segment_lat segment_lon flag_meanings String none arctic global mss antarctic flag_values Int32 0 1 2 3 4 _FillValue Int32 2147483647 long_name String dem source flag segment_fpb_correction /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String First photon bias correction units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String First photon bias correction. May be applied at user disrection by subtracting from mean height produts ht_ortho and ht_water_surf. coordinates String delta_time segment_lat segment_lon segment_azimuth /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Azimuth standard_name String azimuth units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. coordinates String delta_time segment_lat segment_lon inland_water_body_size /gt2l/delta_time _FillValue Int8 127 long_name String Body size units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 0 valid_max Int8 9 contentType String referenceInformation description String Size of Inland Water Body, A=area, where 0=Not_Assigned, 1=A>10,000 sq km, 2=10,000>A>=1,000, 3=1,000>A>=100, 4=100>A>=10, 5=10>A>=1, 6=1>A>=0.1, 7=0.01>A, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String not_assigned area_gt_10000 10000_gt_area_ge_1000 1000_gt_area_ge_100 100_gt_area_ge_10 10_gt_area_ge_1 1_gt_area_ge_0.1 0.01_gt_area Reserved Reserved flag_values Int8 0 1 2 3 4 5 6 7 8 9 met_wind10_atl13 /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height, based on derived water surface wave height. coordinates String delta_time segment_lat segment_lon snow_ice_atl09 /gt2l/delta_time _FillValue Int32 2147483647 long_name String Snow Ice Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) contentType String modelResult description String NOAA snow/ice flag scaled by ATL09 (0=ice-free water, 1=snow-free land, 2=snow, 3=ice, 127=invalid) coordinates String delta_time segment_lat segment_lon flag_meanings String ice_free_water snow_free_land snow ice invalid flag_values Int32 0 1 2 3 127 segment_tide_ocean /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Ocean units String meters source String ATL03 contentType String auxiliaryInformation description String Ocean tides including diurnal and semi-diurnal (harmonic analysis (+-4 m)). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon err_slope_trk /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Slope Error units String 1 source String section 5.3.3 (C) contentType String qualityInformation description String Error included in segment_slope_trk_local. coordinates String delta_time segment_lat segment_lon segment_slope_trk_bdy /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Water Body Slope units String m/m source String ATL13 ATBD, Section 5.3.5 (A) contentType String physicalMeasurement description String Along track water body surface slope, reported per short segment ID per water body. coordinates String delta_time segment_lat segment_lon sseg_mean_lat /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Mean latitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon segment_geoid_free2mean /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Geoid Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Value to convert segment geoid heights from the mean-tide system to the tide-free system. Subtract this value from mean-tide system segment_geoid (on ATL13) to get geoid heights in the tide-free system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_spec_width /gt2l/delta_time _FillValue Int8 127 long_name String Spectral width Flag units String 1 source String ATL13 ATBD, Section 4.8.8 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Spectral moments width flag. The flag is set as follows: 0 when spec_width is invalid; 1 when 0 <= spec_width <= 0.2; 2 when 0.2 < spec_width <= 0.3; 3 when 0.3 < spec_width <= 0.4; 4 when 0.4 < spec_width <= 0.5; 5 when 0.5 < spec_width <= 0.6; 6 when 0.6 < spec_width <= 0.7; 7 when 0.7 < spec_width <= 0.8; 8 when 0.8 < spec_width <= 0.9; 9 when 0.9 < spec_width. coordinates String delta_time segment_lat segment_lon flag_meanings String invalid 0<=spec_width<=0.2 0.2<spec_width<=0.3 0.3<spec_width<=0.4 0.4<spec_width<=0.5 0.5<spec_width<=0.6 0.6<spec_width<=0.7 0.7<spec_width<=0.8 0.8<spec_width<=0.9 0.9<spec_width flag_values Int8 0 1 2 3 4 5 6 7 8 9 qf_bckgrd /gt2l/delta_time _FillValue Int8 127 long_name String Background Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 6 contentType String qualityInformation description String Describes the degree of background photons present in each short segment. bckgrd_dnsty_threshold1= 0.001 (counts per bi per Lseg); bckgrd_dnsty_threshold2= 0.01 (counts per bin per Lseg); bckgrd_dnsty_threshold3= 0.05 (counts per bin per Lseg); bckgrd_dnsty_threshold4= 0.1 (counts per bin per Lseg); bckgrd_dnsty_threshold5= 0.3 (counts per bin per Lseg); bckgrd_dnsty_threshold6= 0.5 (counts per bin per Lseg) coordinates String delta_time segment_lat segment_lon flag_meanings String equal_to_or_below_threshold1 equal_to_or_below_threshold2 equal_to_or_below_threshold3 equal_to_or_below_threshold4 equal_to_or_below_threshold5 equal_to_or_below_threshold6 above_threshold6 flag_values Int8 0 1 2 3 4 5 6 sseg_mean_time /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean time standard_name String time units String Seconds since 2018-01-01 source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Mean time of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon met_ts_atl09 /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface temperature standard_name String temperature units String K source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Surface (skin) temperature from ATL09. coordinates String delta_time segment_lat segment_lon segment_bias_em /gt2l/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Electromagnetic bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Electromagnetic bias. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon segment_dem_ht /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String DEM Height units String meters source String ATL13 ATBD, Section 5.3.5 contentType String referenceInformation description String DEM height relative to WGS-84 ellipsoid, reported at the short segment rate. coordinates String delta_time segment_lat segment_lon subsurface_backscat_ampltd /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface backscatter amplitude units String 1 source String Section 5.3.4 (A) contentType String modelResult description String Subsurface backscatter amplitude, described in section 4.5.3, reported per long segment (default length = 10 short segments = approximately 1000 signal photons). coordinates String delta_time segment_lat segment_lon segment_dac /gt2l/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment DAC units String meters source String ATBD Section 5.3.5A contentType String auxiliaryInformation description String Dynamic atmospheric correction (DAC) includes inverted barometer (IB) effect (+- 5 cm). Although available at short segment rate for all water body types, value is provided mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon DODS_EXTRA Container Unlimited_Dimension String delta_time description String Contains per-beam data products. data_rate String Data within this group are stored at the inland water short segment rate (/ancillary_data/inland_water/s_seg2). atlas_pce String pce2 atlas_beam_type String weak groundtrack_id String gt2l atmosphere_profile String profile_2 atlas_spot_number String 4 sc_orientation String Forward anom_ssegs anom_sseg_time 2377 anom_sseg_lat /gt2l/anom_ssegs/anom_sseg_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of the short segment (mean of signal class >=2 ph Lats). coordinates String anom_sseg_time anom_sseg_lon anom_sseg_time /gt2l/anom_ssegs/anom_sseg_time long_name String Delta Time standard_name String time units String sec source String ATL13 ATBD, Table 5-4b contentType String physicalMeasurement description String Time of the short segment (mean of signal class >=2 ph time). coordinates String anom_sseg_lat anom_sseg_lon anom_sseg_lon /gt2l/anom_ssegs/anom_sseg_time long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of the short segment (mean of signal class >=2 ph Lons). coordinates String anom_sseg_time anom_sseg_lat transect_id /gt2l/anom_ssegs/anom_sseg_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon cycle_number /gt2l/anom_ssegs/anom_sseg_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon rgt /gt2l/anom_ssegs/anom_sseg_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_sig_ph_cnt /gt2l/anom_ssegs/anom_sseg_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_trigger_flag /gt2l/anom_ssegs/anom_sseg_time /ds_anom_trigger _FillValue Int8 127 long_name String Anomalous classification flag units String 1 source String ATL13 ATBD, Table 5-4b valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Nine element array describing justification for short segment classification as anomalous, where for each element 0 = not triggered as anomalous and 1 = triggered as anomalous due to any of the following causes: [element 1=coarse ht difference, element 2=abnormal length, element 3= histogram mode spread, element 4=histogram mode count, element 5=histogram mode intensity, element 6=invalid long segment, element 7=shore buffer designation, element 8=insufficient signal phs, element 9=transect coarse water height unavailable against which to test short segment height] coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon flag_meanings String not_triggered_as_anomalous triggered_as_anomalous flag_values Int8 0 1 anom_sseg_stdev /gt2l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Segment standard deviation units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Standard deviation of anomalous short segment photon height in the anomalous short segment with signal classification >= 2. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_ht_delta /gt2l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Height difference units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height difference between anom_sseg_mode of the anomalous short segment and the transect coarse_transect_ht. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_length /gt2l/anom_ssegs/anom_sseg_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Length of the short segment, based on end points computed by the average of sseg_endpoint_avg_n signal photons. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lon /gt2l/anom_ssegs/anom_sseg_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String End longitude of the anomalous short segment, based on the average longitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon coarse_transect_ht /gt2l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Coarse water height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Coarse water height of transect. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon atl13refid /gt2l/anom_ssegs/anom_sseg_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mode /gt2l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Anomalous mode bin height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height of anomalous short segment as determined by histogram bin mode. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_quality /gt2l/anom_ssegs/anom_sseg_time /ds_sseg_quality long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each anomalous short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon _FillValue Int32 2147483647 anom_sseg_start_lon /gt2l/anom_ssegs/anom_sseg_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Start longitude of the anomalous short segment, based on the average longitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mean_ht_ortho /gt2l/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height of anomalous short segment as determined by the mean of photon orthometric heights in the anomalous short segment with signal classification >2 coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_start_lat /gt2l/anom_ssegs/anom_sseg_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Start latitude of the anomalous short segment, based on the average latitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lat /gt2l/anom_ssegs/anom_sseg_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String End latitude of the anomalous short segment, based on the average latitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon DODS_EXTRA Container Unlimited_Dimension String anom_sseg_time description String Contains per-beam anomalous short segment output parameters. ancillary_data release 1 long_name String Release Number units String 1 source String Operations contentType String auxiliaryInformation description String Release number of the granule. The release number is incremented when the software or ancillary data used to create the granule has been changed. end_geoseg 1 long_name String Ending Geolocation Segment units String 1 source String Derived contentType String auxiliaryInformation description String The ending geolocation segment number associated with the data contained within this granule. ICESat granule geographic regions are further refined by geolocation segments. During the geolocation process, a geolocation segment is created approximately every 20m from the start of the orbit to the end. The geolocation segments help align the ATLAS strong a weak beams and provide a common segment length for the L2 and higher products. The geolocation segment indices differ slightly from orbit-to-orbit because of the irregular shape of the Earth. The geolocation segment indices on ATL01 and ATL02 are only approximate because beams have not been aligned at the time of their creation. version 1 long_name String Version units String 1 source String Operations contentType String auxiliaryInformation description String Version number of this granule within the release. It is a sequential number corresponding to the number of times the granule has been reprocessed for the current release. end_region 1 long_name String Ending Region units String 1 source String Derived contentType String auxiliaryInformation description String The ending product-specific region number associated with the data contained within this granule. ICESat-2 data products are separated by geographic regions. The data contained within a specific region are the same for ATL01 and ATL02. ATL03 regions differ slightly because of different geolocation segment locations caused by the irregular shape of the Earth. The region indices for other products are completely independent. atlas_sdp_gps_epoch 1 long_name String ATLAS Epoch Offset units String seconds since 1980-01-06T00:00:00.000000Z source String Operations contentType String auxiliaryInformation description String Number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS Standard Data Product (SDP) epoch (2018-01-01:T00.00.00.000000 UTC). Add this value to delta time parameters to compute full gps_seconds (relative to the GPS epoch) for each data point. end_rgt 1 long_name String Ending Reference Groundtrack units String 1 source String Derived valid_min Int32 1 valid_max Int32 1387 contentType String auxiliaryInformation description String The ending reference groundtrack (RGT) number associated with the data contained within this granule. There are 1387 reference groundtrack in the ICESat-2 repeat orbit. The reference groundtrack increments each time the spacecraft completes a full orbit of the Earth and resets to 1 each time the spacecraft completes a full cycle. end_delta_time 1 long_name String ATLAS End Time (Actual) standard_name String time units String seconds since 2018-01-01 source String Derived contentType String auxiliaryInformation description String Number of GPS seconds since the ATLAS SDP epoch at the last data point in the file. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. end_orbit 1 long_name String Ending Orbit Number units String 1 source String Derived contentType String auxiliaryInformation description String The ending orbit number associated with the data contained within this granule. The orbit number increments each time the spacecraft completes a full orbit of the Earth. start_cycle 1 long_name String Starting Cycle units String 1 source String Derived valid_min Int32 0 valid_max Int32 99 contentType String auxiliaryInformation description String The starting cycle number associated with the data contained within this granule. The cycle number is the counter of the number of 91-day repeat cycles completed by the mission. data_end_utc 1 long_name String End UTC Time of Granule (CCSDS-A, Actual) units String 1 source String Derived contentType String auxiliaryInformation description String UTC (in CCSDS-A format) of the last data point within the granule. control 1 long_name String Control File units String 1 source String Operations contentType String auxiliaryInformation description String PGE-specific control file used to generate this granule. To re-use, replace breaks (BR) with linefeeds. start_gpssow 1 long_name String Start GPS SOW of Granule (Actual) units String seconds source String Derived contentType String auxiliaryInformation description String GPS seconds-of-week of the first data point in the granule. granule_end_utc 1 long_name String End UTC Time of Granule (CCSDS-A, Requested) units String 1 source String Derived contentType String auxiliaryInformation description String Requested end time (in UTC CCSDS-A) of this granule. end_cycle 1 long_name String Ending Cycle units String 1 source String Derived valid_min Int32 0 valid_max Int32 99 contentType String auxiliaryInformation description String The ending cycle number associated with the data contained within this granule. The cycle number is the counter of the number of 91-day repeat cycles completed by the mission. granule_start_utc 1 long_name String Start UTC Time of Granule (CCSDS-A, Requested) units String 1 source String Derived contentType String auxiliaryInformation description String Requested start time (in UTC CCSDS-A) of this granule. start_delta_time 1 long_name String ATLAS Start Time (Actual) standard_name String time units String seconds since 2018-01-01 source String Derived contentType String auxiliaryInformation description String Number of GPS seconds since the ATLAS SDP epoch at the first data point in the file. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. start_geoseg 1 long_name String Starting Geolocation Segment units String 1 source String Derived contentType String auxiliaryInformation description String The starting geolocation segment number associated with the data contained within this granule. ICESat granule geographic regions are further refined by geolocation segments. During the geolocation process, a geolocation segment is created approximately every 20m from the start of the orbit to the end. The geolocation segments help align the ATLAS strong a weak beams and provide a common segment length for the L2 and higher products. The geolocation segment indices differ slightly from orbit-to-orbit because of the irregular shape of the Earth. The geolocation segment indices on ATL01 and ATL02 are only approximate because beams have not been aligned at the time of their creation. start_orbit 1 long_name String Starting Orbit Number units String 1 source String Derived contentType String auxiliaryInformation description String The starting orbit number associated with the data contained within this granule. The orbit number increments each time the spacecraft completes a full orbit of the Earth. data_start_utc 1 long_name String Start UTC Time of Granule (CCSDS-A, Actual) units String 1 source String Derived contentType String auxiliaryInformation description String UTC (in CCSDS-A format) of the first data point within the granule. end_gpsweek 1 long_name String Ending GPSWeek of Granule (Actual) contentType String auxiliaryInformation description String GPS week number of the last data point in the granule. units String weeks from 1980-01-06 source String Derived start_rgt 1 long_name String Starting Reference Groundtrack units String 1 source String Derived valid_min Int32 1 valid_max Int32 1387 contentType String auxiliaryInformation description String The starting reference groundtrack (RGT) number associated with the data contained within this granule. There are 1387 reference groundtrack in the ICESat-2 repeat orbit. The reference groundtrack increments each time the spacecraft completes a full orbit of the Earth and resets to 1 each time the spacecraft completes a full cycle. end_gpssow 1 long_name String Ending GPS SOW of Granule (Actual) units String seconds source String Derived contentType String auxiliaryInformation description String GPS seconds-of-week of the last data point in the granule. start_region 1 long_name String Starting Region units String 1 source String Derived contentType String auxiliaryInformation description String The starting product-specific region number associated with the data contained within this granule. ICESat-2 data products are separated by geographic regions. The data contained within a specific region are the same for ATL01 and ATL02. ATL03 regions differ slightly because of different geolocation segment locations caused by the irregular shape of the Earth. The region indices for other products are completely independent. start_gpsweek 1 long_name String Start GPSWeek of Granule (Actual) units String weeks from 1980-01-06 source String Derived contentType String auxiliaryInformation description String GPS week number of the first data point in the granule. data_rate String Data within this group pertain to the granule in its entirety. description String Contains information ancillary to the data product. This may include product characteristics, instrument characteristics and/or processing constants. inland_water n_coarse_iter 9 3 _FillValue Int8 127 long_name String Number of coarse iterations units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of coarse iteration steps for amplitude, mean height and standard deviation for surface iterated convolution. atm_window2 1 long_name String ATM Background Window Top units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Upper limit of height above coarse water surface height for atmospheric background count calculation. b1_sseg1 1 long_name String Small Segment Bin Size units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Bin size to be used for histogramming of each small segment. s_seg1 9 _FillValue Int32 2147483647 long_name String Short Segment Length units String 1 source String ATBD Table 5-2 valid_min Int32 1 valid_max Int32 500 contentType String auxiliaryInformation description String Short segment size, indicating the number of along track signal photons per segment, operationally used as unit length over which to identify water surface height anomalies such as islands, bridges, etc. detrend_width 1 long_name String Detrend Width units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of standard deviations +/- mode to include in detrend band. sub_max 1 long_name String Subsurf Max Vertical Profile units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Maximum vertical profile of water subsurface to include in estimation of subsurface characteristics btm_upper_range_bins 1 long_name String bin count above apparent bottom height units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of bins above the long segment derived apparent bottom height over which to include member photons in short segment scale bottom finding adjustment. detection_ratio 9 _FillValue Float32 3.402823466e+38 long_name String threshold adjustment units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 contentType String auxiliaryInformation description String Based on water body type, an adjustment to the threshold tests that must be passed in order to be identified as subsurface. lidar_coeff_alpha_unit_max 9 2 long_name String Subsurface parameters units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Coefficient multiplier of unit exponential distribution and subsurface alpha_unit maximum values of iteration loops used in deconvolution, described in section 5.3.4 (A), based on water body type. bottom_find_method 9 _FillValue Int8 127 long_name String bathymetry identification method units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 valid_min Int8 0 valid_max Int8 2 contentType String auxiliaryInformation description String Based on water body type, the method by which to identify bathymetry in the subsurface. flag_meanings String do_not_search_for_bathymetry do_not_apply_density_threshold_coupling apply_density_threshold_coupling flag_values Int8 0 1 2 ref_dist_iw_bdy 1 long_name String Reference Difference units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Maximum distance from a water body that a geosegment reference photon indicates the need for overlap testing each individual photon in the geosegment geoseg_edge_buffer 9 9 _FillValue Int8 127 long_name String geosegment edge buffer units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 valid_min Int8 0 valid_max Int8 5 contentType String auxiliaryInformation description String Number of geosegments to include in the water surface calculation that are outside of both water body edges, as identified by reference photon location comparison to water body shapes. flag_meanings String buffer_0 buffer_1 buffer_2 buffer_3 buffer_4 buffer_5 flag_values Int8 0 1 2 3 4 5 min_mirror_cnt 9 5 long_name String minimum mirror count units String 1 source String ATL13 ATBD, Section 5.2, Table 5-1 contentType String auxiliaryInformation description String Minimum number of signal photons required in a fully-filled long or very segment (consisting of only full member short segments) in each step of mirroring approach to estimating observed surface mean and standard deviation, designated by water body type. sseg_mode_freq_test 1 long_name String Short Segment Mode Frequency Test units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Threshold to test number of short segment histogram modes against for inclusion or exclusion of short segment. type_to_process 9 _FillValue Int8 127 long_name String Type to Process units String 1 source String ATL13 ATBD, Section 4.7.1.2, Table 5-4 valid_min Int8 0 valid_max Int8 1 contentType String auxiliaryInformation description String Water body types that are to be processed by the ATL13 algorithm. This parameter is a rank 1 array of extent 9, with the body type digits coinciding with the array subscripts 1 through 9. Array elements are binary values, if 0 then process body type, 1 otherwise. Water body types are described in ATL13 chapter 4.7.1.2 and in Table 5-4. flag_meanings String process_type otherwise flag_values Int8 0 1 apply_mirror 9 long_name String Apply mirror scheme units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 valid_min Byte 0 valid_max Byte 1 contentType String auxiliaryInformation description String By water body type, designation as to whether or not to apply the multi-step mirroring scheme for surface estimation, where 0= do not apply mirroring and 1=process water body through mirroring steps. flag_meanings String do_not_apply_mirroring process_through_mirroring flag_values Byte 0 1 sig_threshold 1 long_name String Signal Confidence Threshold units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Minimum signal confidence required for photon to be included in analysis size_to_process 9 9 _FillValue Int8 127 long_name String Size to Process units String 1 source String ATL13 ATBD, Section 4.7.1.2, Table 5-4 valid_min Int8 0 valid_max Int8 1 contentType String auxiliaryInformation description String Water body sizes that are to be processed by the ATL13 algorithm for each water body type. This parameter is a rank 2 array of size 9x9, where array subscripts 1 through 9, coincide with body type digits along columns, and body size digits along rows. Array elements are binary values, if 0 then process body size for that type, 1 otherwise. Water body sizes are described in ATL13 chapter 4.7.1.2 and in Table 5-4. flag_meanings String process_size otherwise flag_values Int8 0 1 lidar_coeff_alpha_unit_min 9 2 long_name String Subsurface parameters units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Coefficient multiplier of unit exponential distribution and subsurface alpha_unit minimum values of iteration loops used in deconvolution, described in section 5.3.4 (A), based on water body type. aggregate_ratio 9 _FillValue Float32 3.402823466e+38 long_name String bin count ratio units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 contentType String auxiliaryInformation description String Based on water body type, the required bin counts that must exist above and inclusive of a subsurface bin relative to the count of the entire column in order to qualify as possible bottom. lidar_coeff_alpha_unit_incr 9 2 long_name String Subsurface parameters units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Iteration loop coefficient multiplier of unit exponential distribution and subsurface alpha_unit step increments used in deconvolution, described in section 5.3.4 (A), based on water body type. gauss_pk_thres 1 long_name String Gaussian Peak Threshold units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Fraction of the peak amplitude above which Gaussian fit error analysis is executed (ie, calculate error on Gaussian only between the peak amplitude and gauss_pk_thres * peak) sseg_mode_cnt_test 6 _FillValue Int8 127 long_name String Short segment mode count test units String 1 source String ATBD Table 5-2 valid_min Int8 7 valid_max Int8 10 contentType String referenceInformation description String Threshold to test number of values contained in short segment histogram multimodes against for inclusion or exclusion of short segment flag_meanings String sseg_stdev_thres_1 sseg_stdev_thres_2 sseg_stdev_thres_3 sseg_stdev_thres_4 sseg_stdev_thres_5 sseg_stdev_thres_6 flag_values Int8 10 10 7 7 7 7 shore_buffer 9 9 _FillValue Int8 127 long_name String Shore buffer units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 valid_min Int8 0 valid_max Int8 1 contentType String auxiliaryInformation description String Number of near-shore short segments to ignore in analysis due to near-shore influences. flag_meanings String buffer_0 buffer_1 flag_values Int8 0 1 h_mavg_c 1 long_name String Num Depth Bins C units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of bins over which to calculate moving average bckgrd_threshold 2 long_name String Background Threshold units String counts/sec source String ATBD Table 5-2 contentType String auxiliaryInformation description String Thresholds outside of which computed background is flagged (High, Low). n2 9 long_name String refractive index of water units String 1 source String ATL13 ATBD Section 5.3.2 C contentType String auxiliaryInformation description String Refractive index of water for a processed water body. f2_d_min 1 long_name String Minimum Distance Thres units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Minimum distance threshold between photons required for inclusion in algorithm. max_gseg_search 1 long_name String Max Geoseg Search Radius units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Maximum number of geosegments in either direction to search for reported water surface heights sseg_length_test 9 _FillValue Float32 3.402823466e+38 long_name String Short Segment Length Test units String meters source String ATBD Table 5-2 valid_min Float32 1. valid_max Float32 500. contentType String auxiliaryInformation description String Threshold by which to test the length of a short segment to determine anomalous or not anomalous, varying by water body type. h_mavg_a 1 long_name String Num Depth Bins A units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of depth bins over which to compute H_mavg_a signal_window_bottom 1 long_name String Signal Window Bottom units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Lower limit below coarse water surface to include photons for analysis. amp_mean_sig_min 3 _FillValue Float32 3.402823466e+38 long_name String iteration loop minimum values units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Amplitude, mean, and sigma minimum values of iteration loops used in deconvolution described in section 5.3.4(B) bottom_sseg_mean_min 1 long_name String Minimum photon count for downscaling bottom units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Minimum number of photons required to calculate a valid mean while downscaling a found bottom into short segment rate output. amp_mean_sig_nskip 9 3 _FillValue Int8 127 long_name String Skip factor for surface iterated convolution units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of amplitude, mean height and standard deviation values skipped based on body type, within coarse iteration loops of amplitude, HM_unit and sigma_unit used in deconvolution described in section 5.3.4 (B), to determine an approximate error minimum location over the surface profile range. c_fresnel 1 long_name String Fresnel Coeff units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Fresnel specular reflection coefficient @ 532 nm sseg_mode_spread_test 1 long_name String Short Segment Mode Spread Test units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Threshold to test distance between short segment histogram multimodes against for inclusion or exclusion of short segment. anmly_test 9 12 long_name String Anomaly Test units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Array containing threshold values against which to test segments for heights that are anomalous to the rest of the water surface. The anmly_test value is selected based on the corresponding length of the water body crossing, calculated in the code as iw_bdy_xlen_flag. The mode of each segment histogram will be tested against ht_water_coarse and marked as anomalous if the difference is greater than the anomaly test value associated with the segment crossing length. h_mavg_b 1 long_name String Num Depth Bins B units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of depth bins over which to compute H_mavg_b limit_hist_depth 9 long_name String Limit histogram depth analysis units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 valid_min Byte 0 valid_max Byte 1 contentType String auxiliaryInformation description String By water body type, designation as to whether or not to limit the initial short segment histogram depth analysis by range_hist_depth, where 0= do not limit depth range and 1= limit the depth range consideration by range_hist_depth. flag_meanings String do_not_limit_depth_range limit_depth_range flag_values Byte 0 1 b_long 1 long_name String Long Bin Size units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Bin size to be used by which to establish a histogram of long segments. amp_mean_sig_incr 3 _FillValue Float32 3.402823466e+38 long_name String iteration loop increments units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Iteration loop amplitude, mean, and sigma step increments used in deconvolution described in section 5.3.4(B) bin_detrend 1 long_name String Detrend Bin Size units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Bin size used to establish a band of heights over which to determine the detrending equation. atm_window1 1 long_name String ATM Background Window Bottom units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Lower limit of height above coarse water surface height for atmospheric background count calculation. m_avg_d 1 long_name String Num Depth Bins D units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of depth bins over which to compute P_ht_long_subsurf_mavg refr_idx_type 9 long_name String array index for refractive index of water units String 1 source String ATL13 ATBD Section 5.3.2 C contentType String auxiliaryInformation description String Array indices denoting refractive index of water for a processed water body. amp_mean_sig_max 3 _FillValue Float32 3.402823466e+38 long_name String iteration loop maximum values units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Amplitude, mean, and sigma maximum values of iteration loops used in deconvolution described in section 5.3.4(B) l_surf 9 _FillValue Int32 2147483647 long_name String Long Surface Segment Size units String 1 source String ATBD Table 5-2 valid_min Int32 10 valid_max Int32 5000 contentType String auxiliaryInformation description String Long segment size, operationally used as unit length over which to detrend the water surface, characterize the surface, and deconvolve the instrument pulse and subsurface effects from the water surface response. signal_window_top 1 long_name String Signal Window Top units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Upper limit above coarse water surface to include photons for analysis. btm_lower_range_bins 1 long_name String bin count below apparent bottom height units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Number of bins below the long segment derived apparent bottom height over which to include member photons in short segment scale bottom finding adjustment. lsbr_threshold 1 long_name String LSBR Threshold units String 1 source String ATBD Table 5-2 contentType String auxiliaryInformation description String Threshold at which the LSBR indicates a significant transition from signal photon richness to noise. l_sub 9 _FillValue Int32 2147483647 long_name String Long subsurface segment size units String 1 source String ATBD Table 5-2 valid_min Int32 30 valid_max Int32 15000 contentType String auxiliaryInformation description String Long segment size, operationally used as unit length over which to characterize the subsurface, and deconvolve the instrument pulse and subsurface effects from the water surface response. b2_sseg1 1 long_name String Small Segment Height Bin Size units String meters source String ATBD Table 5-2 contentType String auxiliaryInformation description String Bin size to be used for histogramming of small segment heights. shore_buff_sseg_length 1 long_name String Shore buffer short segment length units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 contentType String auxiliaryInformation description String Maximum length of a short segment that can be marked as anomalous due to shore buffering. range_hist_depth 9 long_name String Limiting depth for histogram analysis units String 1 source String ATL13 ATBD, Section 5.2, Table 5-2 contentType String auxiliaryInformation description String Depth at which to limit the initial short segment histogram analysis, if utilized for the body type as designated by limit_hist_depth. description String Contains general ancillary parameters. gt3r delta_time 43586 segment_lon /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lat /gt3r/delta_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of reporting location for all short segment statistics. coordinates String delta_time segment_lon delta_time /gt3r/delta_time long_name String Delta Time standard_name String time units String seconds since 2018-01-01 source String ATL03 contentType String physicalMeasurement description String Number of GPS seconds since the ATLAS SDP epoch. The ATLAS Standard Data Products (SDP) epoch offset is defined within /ancillary_data/atlas_sdp_gps_epoch as the number of GPS seconds between the GPS epoch (1980-01-06T00:00:00.000000Z UTC) and the ATLAS SDP epoch. By adding the offset contained within atlas_sdp_gps_epoch to delta time parameters, the time in gps_seconds relative to the GPS epoch can be computed. coordinates String segment_lat segment_lon sseg_sig_ph_cnt /gt3r/delta_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String delta_time segment_lat segment_lon sseg_dist_from_eq /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Distance from equator to segment start standard_name String Along-track distance units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Along-track distance from the equator to the first photon in the short segment. coordinates String delta_time segment_lat segment_lon qf_bias_fit /gt3r/delta_time _FillValue Int8 127 long_name String Height Bias Fit Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The height bias fit flag is set based on the value of the goodness of fit bias estimated as the difference between the centroid elevations of the observed surface water histogram and fitted integrated water surface model histogram. The flag values are set as follows: = -3 if H_bias_fit < -0.10 (m); -2 if -0.10 <= H_bias_fit < -0.05;-1 when -0.05 <= H_bias_fit < -0.01; 0 if -0.01 <= H_bias_fit < 0.01 (m); 1 if 0.01 <= H_bias_fit < 0.05; 2 if 0.05 < H_bias_fit < 0.10; 3 if 0.10 <= H_bias_fit; 4 if H_bias_fit is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 equal_to_or_above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 sseg_mean_lon /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Mean longitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon cloud_flag_atm_atl09 /gt3r/delta_time _FillValue Int8 127 long_name String Cloud Flag Atm units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 10 contentType String modelResult description String Cloud flag from backscatter profile. coordinates String delta_time segment_lat segment_lon qf_ice /gt3r/delta_time _FillValue Int8 127 long_name String Ice Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The quality flag for ice describes the likelihood of ice on the short water body surface segment. 0 for QF_Bckgrd<= 2; 1 for 2 < QF_Bckgrd<= 4; 2 for 4 < QF_Bckgrd; 3 for (4 < QF_Bckgrd and QF_Cloud=1) coordinates String delta_time segment_lat segment_lon flag_meanings String qf_bckgrd_le_2 qf_bckgrd_le_4 qf_bckgrd_gt_4 qf_bckgrd_w_cloud flag_values Int8 0 1 2 3 transect_id /gt3r/delta_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String delta_time segment_lat segment_lon inland_water_body_type /gt3r/delta_time _FillValue Int8 127 long_name String Body type units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Type of Inland Water Body, where 1=Lake, 2=Known Reservoir, 3=(Reserved for future use), 4=Ephemeral Water, 5=River, 6=Estuary or Bay, 7=Coastal Water, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String Lake Known_Reservoir Reserved_for_future_use Ephemeral_Water River Estuary_or_Bay Coastal_Water Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 inland_water_body_id /gt3r/delta_time _FillValue Int32 2147483647 long_name String Body ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Identifying signature of an individual inland water body. Each body of water is represented by a unique numeric value. coordinates String delta_time segment_lat segment_lon sseg_end_lon /gt3r/delta_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon qf_subsurface_attenuation /gt3r/delta_time _FillValue Int8 127 long_name String Subsurface attenuation quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface attenuation was constrained during deconvolution by the minimum (initial) limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the subsurface attenuation fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for subsurface attenuation is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 segment_quality /gt3r/delta_time /ds_sseg_quality _FillValue Int32 2147483647 long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String delta_time segment_lat segment_lon segment_geoid /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Geoid units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Applicable mean-tide system geoid value at reporting location for all short segment statistics. (see geoid_free2mean to convert to the tide-free system.) coordinates String delta_time segment_lat segment_lon qf_sseg_length /gt3r/delta_time _FillValue Int8 127 long_name String Short Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Length of short segments flag. The flag is set as follows: 0 if sseg_length < 10 (meters); 1 if 10 <= sseg_length < 20 (meters); 2 if 20 <= sseg_length < 30 (meters); 3 if 30 <= sseg_length < 50 (meters); 4 if 50 <= sseg_length < 75 (meters); 5 if 75 <= sseg_length < 100 (meters); 6 if 100 <= sseg_length < 150 (meters); 7 if 150 <= sseg_length < 200 (meters); 8 if 200 <= sseg_length < 300 (meters); 9 if 300 <= sseg_length. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 below_threshold9 equal_to_or_above_threshold9 flag_values Int8 0 1 2 3 4 5 6 7 8 9 sseg_start_lon /gt3r/delta_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_tide_equilibrium /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Equilibrium units String meters source String ATL03 contentType String auxiliaryInformation description String Long period equilibrium tide self-consistent with ocean tide model (+- 0.04 m). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon qf_lseg_length /gt3r/delta_time _FillValue Int8 127 long_name String Long Segment Length flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 3 contentType String qualityInformation description String The Long Segment Length flag is set based on the length of the long segment. The flag is set as follows: 0 if Lseg_length < 500 (meters); 1 if 50 <= Lseg_length < 1500 (meters); 2 if 150 <= Lseg_length < 3000 (meters); 3 if 3000 <= Lseg_length coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 above_threshold4 flag_values Int8 0 1 2 3 significant_wave_ht /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String SWH units String meters source String section 5.3.3 (C) contentType String physicalMeasurement description String Significant wave height coordinates String delta_time segment_lat segment_lon bottom_lat /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Bottom latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon cycle_number /gt3r/delta_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String delta_time segment_lat segment_lon qf_subsurface_backscat_ampltd /gt3r/delta_time _FillValue Int8 127 long_name String Subsurface backscatter amplitude quality flag units String 1 source String ATL13 ATBD, Section 5.3.4 (A) valid_min Int8 -2 valid_max Int8 2 contentType String qualityInformation description String Quality flag indicating whether or not the reported subsurface backscatter amplitude was constrained during deconvolution by the minimum limit in the possible range (QF=-1), the maximum limit in the possible range (QF = 1), or was allowed to settle on a solution within the possible range (QF=0). For analysis prior to deconvolution of the backscatter amplitude fit to the observations, the flag indicates whether the value determined by attempting to fit the observations was below (QF= -2), above (QF= 2), or within (QF=0) the possible range of expected values. When the default value for backscatter amplitude is chosen due to any condition other than those defined by an existing quality flag, QF=invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String obs_fit_below_range initial_limit within_range maximum_limit obs_fit_above_range flag_values Int8 -2 -1 0 1 2 water_depth /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water depth units String meters source String ATL13 ATBD, Section 5.3.4 (A) contentType String referenceInformation description String Depth from the mean water surface to detected bottom. coordinates String delta_time segment_lat segment_lon qf_bias_em /gt3r/delta_time _FillValue Int8 127 long_name String EM Bias Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 -3 valid_max Int8 4 contentType String qualityInformation description String The Electromagnetic Bias flag is set based on threshold checks for the estimated electromagnetic height bias. The flag is set as follows: -3 if H_bias_EM < -0.10 (m); -2 if -0.10 < H_bias_EM < -0.05; -1 if -0.05 <= H_bias_EM < -0.01; 0 if -0.01 <= H_bias_EM < 0.01 (m); 1 if 0.01 <= H_bias_EM < 0.05; 2 if 0.05 <= H_bias_EM < 0.10; 3 if 0.10 < H_bias_EM; 4 if H_bias_EM is invalid. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 above_threshold6 invalid flag_values Int8 -3 -2 -1 0 1 2 3 4 segment_id_end /gt3r/delta_time long_name String Last ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String Last ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_stdev_vlseg /gt3r/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the very long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_apparent_ht /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Apparent height of the short segment, before adjustments are made by the algorithm, based on an average of heights within a designated range of the short segment mode. coordinates String delta_time segment_lat segment_lon stdev_water_surf /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface StDev units String meters source String section 5.3.3 (C) contentType String referenceInformation description String Derived standard deviation of water surface, calculated over long segments (when available) with result reported at each short segment location tag contained within. coordinates String delta_time segment_lat segment_lon met_wind10_atl09 /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height from ATL09 input. coordinates String delta_time segment_lat segment_lon qf_iwp /gt3r/delta_time _FillValue Int8 127 long_name String Inland Water Segment Processing Flag units String 1 source String Inland Water ATBD valid_min Int8 1 valid_max Int8 7 contentType String qualityInformation description String Describes the level of processing the inland water algorithm was able to perform based on the data available, ranging from one to 7. coordinates String delta_time segment_lat segment_lon flag_meanings String 1_short_segment 2_short_segments 3_to_5_short_segments 6_to_7_short_segments 8_to_9_short_segments 10_to_29_short_segments at_least_30_short_segments flag_values Int8 1 2 3 4 5 6 7 segment_podppd_flag /gt3r/delta_time _FillValue Int8 0 long_name String POD_PPD Flag units String 1 source String ATL02, ANC04, ANC05 valid_min Int8 0 valid_max Int8 7 contentType String referenceInformation description String Composite POD/PPD flag that indicates the quality of input geolocation products for the utilized ATL03 segments on an ATL13 short segment output basis. A non-zero value may indicate that geolocation solutions are degraded or that ATLAS is within a calibration scan period (CAL). The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible non-CAL values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE; possible CAL values are: 4=CAL_NOMINAL; 5=CAL_POD_DEGRADE; 6=CAL_PPD_DEGRADE; 7=CAL_PODPPD_DEGRADE; coordinates String delta_time flag_meanings String nominal pod_degrade ppd_degrade podppd_degrade cal_nominal cal_pod_degrade cal_ppd_degrade cal_podppd_degrade flag_values Int8 0 1 2 3 4 5 6 7 qf_ht_adj /gt3r/delta_time _FillValue Int8 127 long_name String Height adjustment Quality Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (C) valid_min Int8 -4 valid_max Int8 5 contentType String qualityInformation description String Flag representing the range of height, defined in 5.3.5 (C), which has been added to the apparent surface height due to frame of reference scaling during deconvolution analysis. coordinates String delta_time segment_lat segment_lon flag_meanings String below_threshold1 below_threshold2 below_threshold3 below_threshold4 below_threshold5 below_threshold6 below_threshold7 below_threshold8 equal_to_or_above_threshold8 invalid flag_values Int8 -4 -3 -2 -1 0 1 2 3 4 5 segment_full_sat_fract /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Full Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be fully saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon segment_id_beg /gt3r/delta_time long_name String First ATL03 Segment ID units String 1 source String ATL03 contentType String referenceInformation description String First ATL03 segment_id associated with the photons within this inland water segment. coordinates String delta_time segment_lat segment_lon qf_subsurf_anomaly /gt3r/delta_time _FillValue Int8 127 long_name String Subsurface Anomaly Quality Flag units String 1 source String Inland Water ATBD 5.3.4(A) valid_min Int8 1 valid_max Int8 3 contentType String qualityInformation description String Describes the likelihood that the bottom or other subsurface anomaly is bottom based on the threshold value at which an anomaly was found. 1 = Subsurface anomaly due to bottom likely; 2 = Subsurface signal may indicate bottom or other anomaly; 3 = Possible subsurface anomaly; invalid = No subsurface anomaly detected coordinates String delta_time segment_lat segment_lon flag_meanings String bottom_likely bottom_or_other_anomaly possible_subsurface_anomaly flag_values Int8 1 2 3 subsurface_attenuation /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface Attenuation units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Subsurface attenuation coefficient. coordinates String delta_time segment_lat segment_lon layer_flag_atl09 /gt3r/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Consolidated cloud flag. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_region /gt3r/delta_time _FillValue Int32 2147483647 long_name String Body region units String 1 source String ATL13 ATBD, Section 5.3.1 (A) contentType String referenceInformation description String ATL13-created shapefile representing relevant bodies of water over which to implement the ATL13 water surface finding algorithm only within a region of processing interest. coordinates String delta_time segment_lat segment_lon sseg_end_lat /gt3r/delta_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Latitude at which the short segment ends. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon cloud_flag_asr_atl09 /gt3r/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 (A) valid_min Int8 0 valid_max Int8 5 contentType String modelResult description String Cloud probability from ASR. coordinates String delta_time segment_lat segment_lon flag_meanings String clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence flag_values Int8 0 1 2 3 4 5 _FillValue Int8 127 long_name String Cloud Flag ASR ice_flag /gt3r/delta_time _FillValue Int8 127 long_name String Ice Flag units String 1 source String ATL13 ATBD, section 5.2 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Describes likelihood of ice on water surface short segment. coordinates String delta_time segment_lat segment_lon flag_meanings String no_ice ice flag_values Int8 0 1 sseg_start_lat /gt3r/delta_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.2 (C) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude at which the short segment begins. May be a signal or non-signal photon. coordinates String delta_time segment_lat segment_lon segment_ref_elev /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String elevation standard_name String elevation units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from east-north plane and positive towards up. coordinates String delta_time segment_lat segment_lon segment_apparent_stdev /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Apparent StDev units String meters source String section 5.3.2 (C) contentType String referenceInformation description String Standard deviation of short segment photon height in the short segment with signal classification >= sig_threshold. coordinates String delta_time segment_lat segment_lon ht_ortho /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height EGM2008 converted from ellipsoidal height. coordinates String delta_time segment_lat segment_lon alpha_mle /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Maximum likelihood alpha units String m^-1 source String Section 5.3.4 (A) contentType String physicalMeasurement description String Alpha calculated by maximum likelihood analysis of the subsurface profile range. coordinates String delta_time segment_lat segment_lon rgt /gt3r/delta_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String delta_time segment_lat segment_lon ht_water_surf /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water surface height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Water surface height, reported for each short segment (default length = approximately 100 signal photons) with reference to WGS84 ellipsoid coordinates String delta_time segment_lat segment_lon segment_near_sat_fract /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Near Saturation Fraction units String 1 source String ATL13 ATBD, Section 5.2 valid_min Float32 0. valid_max Float32 1. contentType String qualityInformation description String The fraction of pulses within the short segment determined to be nearly saturated based on ATL03 geosegment rate input. coordinates String delta_time segment_lat segment_lon err_ht_water_surf /gt3r/delta_time units String 1 _FillValue Float32 3.402823466e+38 long_name String Height Error source String section 5.3.3 (C) contentType String qualityInformation description String Error included in heights reported in ht_water_surf. coordinates String delta_time segment_lat segment_lon bottom_lon /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of actual bottom location, based on the apparent bottom sseg_mean_lat / sseg_mean_lon location corrected for refraction effects. coordinates String delta_time segment_lat segment_lon segment_bias_fit /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Goodness of fit bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Bias contribution from goodness of observation/system response fit. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon atl13refid /gt3r/delta_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id coordinates String delta_time segment_lat segment_lon qf_cloud /gt3r/delta_time _FillValue Int8 127 long_name String Consolidated cloud flag units String 1 source String ATL09 valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String This flag is a combination of multiple flags (cloud_flag_atm, cloud_flag_asr, and bsnow_con) and takes daytime/nighttime into consideration. A value of 1 means clouds or blowing snow are likely present. A value of 0 indicates the likely absence of clouds or blowing snow. From the ATL09 data closest to the segment time. coordinates String delta_time segment_lat segment_lon flag_meanings String likely_clear likely_cloudy flag_values Int8 0 1 inland_water_body_source /gt3r/delta_time _FillValue Int8 127 long_name String Body source units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 1 valid_max Int8 9 contentType String referenceInformation description String Source of Inland Water Body shape, where 1=HydroLAKES, 2=Global Lakes and Wetlands Database, 3=Named Marine Water Bodies, 4=GSHHG Shoreline, 5=Global River Widths from Landsat, 6=Reserved, 7=Reserved, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String HydroLAKES Global_Lakes_and_Wetlands_Database Named_Marine_Water_Bodies GSHHG_Shoreline Global_River_Widths_from_Landsat Reserved Reserved Reserved Reserved flag_values Int8 1 2 3 4 5 6 7 8 9 sseg_length /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length standard_name String Length units String meters source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Distance from the first to the last photon in the short segment. coordinates String delta_time segment_lat segment_lon segment_tide_earth_free2mean /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Earth Tide Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Segment rate value to convert solid earth tide from the tide-free system that was applied in ATL03 to photon heights to the ht_water_surf to the mean-tide system. Subtract value from ht_water_surf to reference it in the mean-tide system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_stdev_lseg /gt3r/delta_time _FillValue Int8 127 long_name String observed standard deviation quality flag units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Quality flag indicating the magnitude of standard deviation (SD) of observed detrended heights of the long segment to which the short segment belongs, where 0: SD < 0.5 (meters), 1: 0.5 <= SD < 1.5, 2: 1.5 <= SD < 2.5, 3: 2.5 <= SD < 3.5, 4: 3.5 <= SD < 4.5, 5: 4.5 <= SD < 5.5, 6: 5.5 <= SD < 6.5, 7: 6.5 <= SD < 7.5, 8: 7.5 <= SD < 8.5, 9: 8.5 <= SD. It is recommended that a user consider this flag in conjunction with the water body type and size to best determine if the observed surface standard deviation is reasonable or whether results should be considered questionable. coordinates String delta_time segment_lat segment_lon flag_meanings String SD_below_0.5 SD_below_1.5 SD_below_2.5 SD_below_3.5 SD_below_4.5 SD_below_5.5 SD_below_6.5 SD_below_7.5 SD_below_8.5 SD_greater_or_equal_to_8.5 flag_values Int8 0 1 2 3 4 5 6 7 8 9 segment_dem_source /gt3r/delta_time units String 1 source String ATL13 ATBD, Section 5.3.5 valid_min Int32 0 valid_max Int32 4 contentType String referenceInformation description String Flag equal to the source of the selected photon (in hierarchy of Arctic/Global/MSS/Antarctic). Values: 0=None, 1=Arctic, 2=Global, 3=MSS, 4=Antarctic. coordinates String delta_time segment_lat segment_lon flag_meanings String none arctic global mss antarctic flag_values Int32 0 1 2 3 4 _FillValue Int32 2147483647 long_name String dem source flag segment_fpb_correction /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String First photon bias correction units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String First photon bias correction. May be applied at user disrection by subtracting from mean height produts ht_ortho and ht_water_surf. coordinates String delta_time segment_lat segment_lon segment_azimuth /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Azimuth standard_name String azimuth units String radians source String ATL13 ATBD, Section 5.3.5 (A) contentType String auxiliaryInformation description String The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. coordinates String delta_time segment_lat segment_lon inland_water_body_size /gt3r/delta_time _FillValue Int8 127 long_name String Body size units String 1 source String ATL13 ATBD, Section 5.3.1 (C) valid_min Int8 0 valid_max Int8 9 contentType String referenceInformation description String Size of Inland Water Body, A=area, where 0=Not_Assigned, 1=A>10,000 sq km, 2=10,000>A>=1,000, 3=1,000>A>=100, 4=100>A>=10, 5=10>A>=1, 6=1>A>=0.1, 7=0.01>A, 8=Reserved, 9=Reserved coordinates String delta_time segment_lat segment_lon flag_meanings String not_assigned area_gt_10000 10000_gt_area_ge_1000 1000_gt_area_ge_100 100_gt_area_ge_10 10_gt_area_ge_1 1_gt_area_ge_0.1 0.01_gt_area Reserved Reserved flag_values Int8 0 1 2 3 4 5 6 7 8 9 met_wind10_atl13 /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Wind speed magnitude at 10m standard_name String Wind speed units String m/s source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Wind speed magnitude at 10m height, based on derived water surface wave height. coordinates String delta_time segment_lat segment_lon snow_ice_atl09 /gt3r/delta_time _FillValue Int32 2147483647 long_name String Snow Ice Flag units String 1 source String ATL13 ATBD, Section 5.3.5 (A) contentType String modelResult description String NOAA snow/ice flag scaled by ATL09 (0=ice-free water, 1=snow-free land, 2=snow, 3=ice, 127=invalid) coordinates String delta_time segment_lat segment_lon flag_meanings String ice_free_water snow_free_land snow ice invalid flag_values Int32 0 1 2 3 127 segment_tide_ocean /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment Tide Ocean units String meters source String ATL03 contentType String auxiliaryInformation description String Ocean tides including diurnal and semi-diurnal (harmonic analysis (+-4 m)). Although available at short segment rate for all water body types, value is provide mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon err_slope_trk /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Slope Error units String 1 source String section 5.3.3 (C) contentType String qualityInformation description String Error included in segment_slope_trk_local. coordinates String delta_time segment_lat segment_lon segment_slope_trk_bdy /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Water Body Slope units String m/m source String ATL13 ATBD, Section 5.3.5 (A) contentType String physicalMeasurement description String Along track water body surface slope, reported per short segment ID per water body. coordinates String delta_time segment_lat segment_lon sseg_mean_lat /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Mean latitude of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon segment_geoid_free2mean /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Geoid Free-to-Mean conversion units String meters source String ATL03 ATBD, Section 6.3.8 contentType String auxiliaryInformation description String Value to convert segment geoid heights from the mean-tide system to the tide-free system. Subtract this value from mean-tide system segment_geoid (on ATL13) to get geoid heights in the tide-free system. Applicable value at reporting location for all short segment statistics. coordinates String delta_time segment_lat segment_lon qf_spec_width /gt3r/delta_time _FillValue Int8 127 long_name String Spectral width Flag units String 1 source String ATL13 ATBD, Section 4.8.8 valid_min Int8 0 valid_max Int8 9 contentType String qualityInformation description String Spectral moments width flag. The flag is set as follows: 0 when spec_width is invalid; 1 when 0 <= spec_width <= 0.2; 2 when 0.2 < spec_width <= 0.3; 3 when 0.3 < spec_width <= 0.4; 4 when 0.4 < spec_width <= 0.5; 5 when 0.5 < spec_width <= 0.6; 6 when 0.6 < spec_width <= 0.7; 7 when 0.7 < spec_width <= 0.8; 8 when 0.8 < spec_width <= 0.9; 9 when 0.9 < spec_width. coordinates String delta_time segment_lat segment_lon flag_meanings String invalid 0<=spec_width<=0.2 0.2<spec_width<=0.3 0.3<spec_width<=0.4 0.4<spec_width<=0.5 0.5<spec_width<=0.6 0.6<spec_width<=0.7 0.7<spec_width<=0.8 0.8<spec_width<=0.9 0.9<spec_width flag_values Int8 0 1 2 3 4 5 6 7 8 9 qf_bckgrd /gt3r/delta_time _FillValue Int8 127 long_name String Background Quality Flag units String 1 source String Inland Water ATBD valid_min Int8 0 valid_max Int8 6 contentType String qualityInformation description String Describes the degree of background photons present in each short segment. bckgrd_dnsty_threshold1= 0.001 (counts per bi per Lseg); bckgrd_dnsty_threshold2= 0.01 (counts per bin per Lseg); bckgrd_dnsty_threshold3= 0.05 (counts per bin per Lseg); bckgrd_dnsty_threshold4= 0.1 (counts per bin per Lseg); bckgrd_dnsty_threshold5= 0.3 (counts per bin per Lseg); bckgrd_dnsty_threshold6= 0.5 (counts per bin per Lseg) coordinates String delta_time segment_lat segment_lon flag_meanings String equal_to_or_below_threshold1 equal_to_or_below_threshold2 equal_to_or_below_threshold3 equal_to_or_below_threshold4 equal_to_or_below_threshold5 equal_to_or_below_threshold6 above_threshold6 flag_values Int8 0 1 2 3 4 5 6 sseg_mean_time /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Mean time standard_name String time units String Seconds since 2018-01-01 source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Mean time of the signal-qualified photons in a short segment. coordinates String delta_time segment_lat segment_lon met_ts_atl09 /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Surface temperature standard_name String temperature units String K source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Surface (skin) temperature from ATL09. coordinates String delta_time segment_lat segment_lon segment_bias_em /gt3r/delta_time _FillValue Float64 1.7976931348623157e+308 long_name String Electromagnetic bias units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Electromagnetic bias. (Has been applied to ht_ortho and _ht_water_surf products) coordinates String delta_time segment_lat segment_lon segment_dem_ht /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String DEM Height units String meters source String ATL13 ATBD, Section 5.3.5 contentType String referenceInformation description String DEM height relative to WGS-84 ellipsoid, reported at the short segment rate. coordinates String delta_time segment_lat segment_lon subsurface_backscat_ampltd /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Subsurface backscatter amplitude units String 1 source String Section 5.3.4 (A) contentType String modelResult description String Subsurface backscatter amplitude, described in section 4.5.3, reported per long segment (default length = 10 short segments = approximately 1000 signal photons). coordinates String delta_time segment_lat segment_lon segment_dac /gt3r/delta_time _FillValue Float32 3.402823466e+38 long_name String Segment DAC units String meters source String ATBD Section 5.3.5A contentType String auxiliaryInformation description String Dynamic atmospheric correction (DAC) includes inverted barometer (IB) effect (+- 5 cm). Although available at short segment rate for all water body types, value is provided mainly for transitional tidal and coastal water (types 6 and 7) and the largest lakes of Type 1 (~> 10,000 km2) for user's discretion. coordinates String delta_time segment_lat segment_lon DODS_EXTRA Container Unlimited_Dimension String delta_time description String Contains per-beam data products. data_rate String Data within this group are stored at the inland water short segment rate (/ancillary_data/inland_water/s_seg2). atlas_pce String pce1 atlas_beam_type String strong groundtrack_id String gt3r atmosphere_profile String profile_3 atlas_spot_number String 1 sc_orientation String Forward anom_ssegs anom_sseg_time 8255 anom_sseg_lat /gt3r/anom_ssegs/anom_sseg_time long_name String Latitude standard_name String latitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Latitude of the short segment (mean of signal class >=2 ph Lats). coordinates String anom_sseg_time anom_sseg_lon anom_sseg_time /gt3r/anom_ssegs/anom_sseg_time long_name String Delta Time standard_name String time units String sec source String ATL13 ATBD, Table 5-4b contentType String physicalMeasurement description String Time of the short segment (mean of signal class >=2 ph time). coordinates String anom_sseg_lat anom_sseg_lon anom_sseg_lon /gt3r/anom_ssegs/anom_sseg_time long_name String Longitude standard_name String longitude units String degrees source String ATL13 ATBD, Section 5.3.5 (A) valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Longitude of the short segment (mean of signal class >=2 ph Lons). coordinates String anom_sseg_time anom_sseg_lat transect_id /gt3r/anom_ssegs/anom_sseg_time _FillValue Int8 127 long_name String Transect ID units String 1 source String ATL13 ATBD, Section 5.3.2 (C) contentType String referenceInformation description String Transect within a water body to which the short segment rate output belongs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon cycle_number /gt3r/anom_ssegs/anom_sseg_time long_name String Cycle Number units String counts source String ATL03 valid_min Int8 0 valid_max Int8 50 contentType String referenceInformation description String Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1,387 and adding the RGT value. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon rgt /gt3r/anom_ssegs/anom_sseg_time long_name String Reference Ground track units String 1 source String ATL03 valid_min Int16 1 valid_max Int16 1387 contentType String referenceInformation description String The reference ground track (RGT) is the track on the Earth at which a specified unit vector within the observatory is pointed. Under nominal operating conditions, there will be no data collected along the RGT, as the RGT is spanned by GT2L and GT2R. During slews or off-pointing, it is possible that ground tracks may intersect the RGT. The ICESat-2 mission has 1,387 RGTs. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_sig_ph_cnt /gt3r/anom_ssegs/anom_sseg_time _FillValue Int64 9223372036854775807 long_name String Signal photon count units String 1 source String ATL13 ATBD, Section 5 valid_min Int64 1 valid_max Int64 500 contentType String referenceInformation description String Count of signal photons in short segment, full or partial. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_trigger_flag /gt3r/anom_ssegs/anom_sseg_time /ds_anom_trigger _FillValue Int8 127 long_name String Anomalous classification flag units String 1 source String ATL13 ATBD, Table 5-4b valid_min Int8 0 valid_max Int8 1 contentType String qualityInformation description String Nine element array describing justification for short segment classification as anomalous, where for each element 0 = not triggered as anomalous and 1 = triggered as anomalous due to any of the following causes: [element 1=coarse ht difference, element 2=abnormal length, element 3= histogram mode spread, element 4=histogram mode count, element 5=histogram mode intensity, element 6=invalid long segment, element 7=shore buffer designation, element 8=insufficient signal phs, element 9=transect coarse water height unavailable against which to test short segment height] coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon flag_meanings String not_triggered_as_anomalous triggered_as_anomalous flag_values Int8 0 1 anom_sseg_stdev /gt3r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Segment standard deviation units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Standard deviation of anomalous short segment photon height in the anomalous short segment with signal classification >= 2. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_ht_delta /gt3r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Height difference units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height difference between anom_sseg_mode of the anomalous short segment and the transect coarse_transect_ht. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_length /gt3r/anom_ssegs/anom_sseg_time _FillValue Float64 1.7976931348623157e+308 long_name String Segment length units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Length of the short segment, based on end points computed by the average of sseg_endpoint_avg_n signal photons. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lon /gt3r/anom_ssegs/anom_sseg_time long_name String End longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String End longitude of the anomalous short segment, based on the average longitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon coarse_transect_ht /gt3r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Coarse water height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Coarse water height of transect. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon atl13refid /gt3r/anom_ssegs/anom_sseg_time _FillValue Int64 0 long_name String ATL13 Reference ID units String 1 source String ATL13 ATBD, Section 5.3.1 (C) contentType String referenceInformation description String Unique aggregate reference number for each shape in the ATL13 Inland Water Body Mask, where digit 1 = type, digit 2 = size, digit 3 = source, and digits 4-10 = shape id. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mode /gt3r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Anomalous mode bin height units String meters source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Height of anomalous short segment as determined by histogram bin mode. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_quality /gt3r/anom_ssegs/anom_sseg_time /ds_sseg_quality long_name String Segment quality group count units String 1 source String ATL13 ATBD, Table 5-4b contentType String referenceInformation description String Four-element array of describing, for each anomalous short segment n, the count of photons qualifying in each quality group. (n,1) = nominal, (n,2) = possible afterpulse, (n,3) = possible impulse response effect, (n,4) = possible TEP coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon _FillValue Int32 2147483647 anom_sseg_start_lon /gt3r/anom_ssegs/anom_sseg_time long_name String Start longitude standard_name String longitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -180. valid_max Float64 180. contentType String referenceInformation description String Start longitude of the anomalous short segment, based on the average longitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_mean_ht_ortho /gt3r/anom_ssegs/anom_sseg_time _FillValue Float32 3.402823466e+38 long_name String Orthometric Height units String meters source String ATL13 ATBD, Section 5.3.5 (A) contentType String referenceInformation description String Orthometric height of anomalous short segment as determined by the mean of photon orthometric heights in the anomalous short segment with signal classification >2 coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_start_lat /gt3r/anom_ssegs/anom_sseg_time long_name String Start latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String Start latitude of the anomalous short segment, based on the average latitude of the first sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon anom_sseg_end_lat /gt3r/anom_ssegs/anom_sseg_time long_name String End latitude standard_name String latitude units String degrees source String ATL13 ATBD, Table 5-4b valid_min Float64 -90. valid_max Float64 90. contentType String referenceInformation description String End latitude of the anomalous short segment, based on the average latitude of the last sseg_endpoint_avg_n signal photons in the segment. coordinates String anom_sseg_time anom_sseg_lat anom_sseg_lon DODS_EXTRA Container Unlimited_Dimension String anom_sseg_time description String Contains per-beam anomalous short segment output parameters.