Dataset Information

HDF5_OBJ_FULLPATH: H5_GLOBAL
Conventions: CF-1.6
contributor_name: Thomas E 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: Instrument Engineer, Investigator, Principle Investigator, Data Producer, Data Producer
date_type: UTC
description: The data set (ATL07) contains along-track heights for sea ice and open water leads (at varying length scales) relative to the WGS84 ellipsoid (ITRF2014 reference frame) after adjustment for geoidal and tidal variations, and inverted barometer effects. Heig
featureType: trajectory
geospatial_lat_units: degrees_north
geospatial_lon_units: degrees_east
granule_type: ATL07
identifier_product_doi_authority: http://dx.doi.org
level: L3A
license: 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: http://dx.doi.org
short_name: ATL07
spatial_coverage_type: Horizontal
standard_name_vocabulary: CF-1.6
time_type: CCSDS UTC-A
title: SET_BY_META
date_created: 2020-05-29T14:35:54.000000Z
hdfversion: HDF5 1.10.3
history: 2020-05-29T14:35:54.000000Z;2bed11f8-37e3-3547-bf60-9d7af1919f0d;Created by PGE atlas_l3a_si Version 4.3.2
identifier_file_uuid: 2bed11f8-37e3-3547-bf60-9d7af1919f0d
identifier_product_format_version: 4.3
time_coverage_duration: 5658.
time_coverage_end: 2018-10-14T01:38:05.000000Z
time_coverage_start: 2018-10-14T00:03:47.000000Z
geospatial_lat_min: 68.916474823665695
geospatial_lon_min: 63.30432580191718
geospatial_lat_max: 88.043374802950964
geospatial_lon_max: -136.62047583959989
publisher_name: NSIDC DAAC > NASA National Snow and Ice Data Center Distributed Active Archive Center
publisher_email: nsidc@nsidc.org
publisher_url: http://nsidc.org/daac/
identifier_product_type: ATL07
identifier_product_doi: doi:10.5067/ATLAS/ATL07.003
institution: National Aeronautics and Space Administration (NASA)
creator_name: GSFC I-SIPS > ICESat-2 Science Investigator-led Processing System
summary: The purpose of ATL07 is to provide along-track sea ice heights and associated statistics.
keywords: EARTH SCIENCE > SPECTRAL/ENGINEERING > LIDAR > LIDAR BACKSCATTER > NONE > NONE > NONE
keywords_vocabulary: NASA/GCMD Science Keywords
citation: 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: 2A
references: http://nsidc.org/data/icesat2/data.html
project: ICESat-2 > Ice, Cloud, and land Elevation Satellite-2
instrument: ATLAS > Advanced Topographic Laser Altimeter System
platform: ICESat-2 > Ice, Cloud, and land Elevation Satellite-2
source: Spacecraft


Variables in this Dataset

/orbit_info/crossing_time: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/crossing_time
CLASS: DIMENSION_SCALE
NAME: crossing_time
contentType: referenceInformation
description: 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.
long_name: Ascending Node Crossing Time
source: POD/PPD
standard_name: time
units: seconds since 2018-01-01
/orbit_info/cycle_number: Array of 16 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/cycle_number
contentType: referenceInformation
coordinates: crossing_time
description: A count of the number of exact repeats of this reference orbit.
long_name: Cycle Number
source: Operations
units: 1
valid_max: 50
valid_min: 0
/orbit_info/orbit_number: Array of 16 bit Unsigned integers [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/orbit_number
contentType: referenceInformation
coordinates: crossing_time
description: Unique identifying number for each planned ICESat-2 orbit.
long_name: Orbit Number
source: Operations
units: 1
valid_max: 65000
valid_min: 1
/orbit_info/rgt: Array of 16 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/rgt
contentType: referenceInformation
coordinates: crossing_time
description: 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.
long_name: Reference Ground track
source: POD/PPD
units: 1
valid_max: 1387
valid_min: 1
/orbit_info/sc_orient: Array of 16 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/sc_orient
contentType: referenceInformation
coordinates: sc_orient_time
description: 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.
flag_meanings: backward forward transition
flag_values: 0, 1, 2
long_name: Spacecraft Orientation
source: POD/PPD
units: 1
valid_max: 2
valid_min: 0
/orbit_info/sc_orient_time: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/sc_orient_time
CLASS: DIMENSION_SCALE
NAME: sc_orient_time
contentType: referenceInformation
description: 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.
long_name: Time of Last Spacecraft Orientation Change
source: POD/PPD
standard_name: time
units: seconds since 2018-01-01
/orbit_info/lan: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /orbit_info/lan
contentType: referenceInformation
coordinates: crossing_time
description: Longitude at the ascending node crossing.
long_name: Ascending Node Longitude
source: POD/PPD
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt1r/sea_ice_segments/heights/height_segment_fit_quality_flag: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_fit_quality_flag
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Flag describing the quality of the results of the along-track fit. (-1=height value is invalid; 1=ngrid_w < wlength/2; 2=ngrid_w >= wlength/2; 3=ngrid_dt < dtlength/2; 4=ngrid_dt >= dtlength/2; 5=ngrid_dt >= (dtlength-2): where 1 is best and 5 is poor). Heights are reported even if this flag indicates the height is invalid.
flag_meanings: invalid best high med low poor
flag_values: -1, 1, 2, 3, 4, 5
long_name: height Quality Flag
source: ATBD, section 4.2.4.2
units: 1
valid_max: 5
valid_min: -1
/gt1r/sea_ice_segments/heights/height_segment_length_seg: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_length_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: along-track length of segment containing n_photons_actual
long_name: length of segment
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/heights/height_segment_asr_calc: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_asr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Computed apparent surface reflectance for the sea ice segment.
long_name: Calculated Apparent Surface Reflectivity
source: Sea Ice ATBD
units: 1
/gt1r/sea_ice_segments/heights/height_segment_quality: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_quality
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Height segment quality flag, 1 is good quality, 0 is bad depending on fit, wguassian, or layer flag
flag_meanings: bad_quality good_quality
flag_values: 0, 1
long_name: Height Segment Quality Flag
source: ATBD, section 4.2.4
units: 1
valid_max: 1
valid_min: 0
/gt1r/sea_ice_segments/heights/height_segment_n_pulse_seg: Array of 32 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_n_pulse_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: number of laser pulses
long_name: number of laser pulses
source: ATBD, section 4.2.2.4
units: 1
/gt1r/sea_ice_segments/heights/across_track_distance: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/across_track_distance
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Across track distance of photons averaged over the sea ice height segment.
long_name: Across Track Distance
source: ATBD, section 4.2.4
units: meters
/gt1r/sea_ice_segments/heights/height_segment_htcorr_skew: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_htcorr_skew
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: height corection for skew
long_name: Height Correction for Skew
source: ATBD, section 4.2.6
units: meters
/gt1r/sea_ice_segments/heights/height_segment_ssh_flag: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_ssh_flag
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Identifies the height segments that are candidates for use as sea surface reference in freeboard calculations in ATL10. 0 = sea ice; 1 = sea surface
flag_meanings: sea_ice sea_surface
flag_values: 0, 1
long_name: Sea Surface Flag
source: ATBD, section 4.3
units: 1
valid_max: 1
valid_min: 0
/gt1r/sea_ice_segments/heights/height_segment_height: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_height
coordinates: ../delta_time ../latitude ../longitude
description: Mean height from along-track segment fit detremined by the sea ice algorithm
long_name: height of segment surface
source: ATBD, section 4.2.2.4
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt1r/sea_ice_segments/heights/height_segment_type: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_type
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Value that indicates segment surface type as sea ice or different types of sea surface. 0=cloud covered: rsurf
flag_meanings: cloud_covered other specular_lead_low_w_bkg specular_lead_low specular_lead_high_w_bkg specular_lead_high dark_lead_smooth_w_bkg dark_lead_smooth dark_lead_rough_w_bkg dark_lead_rough
flag_values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
long_name: Segment surface type
source: ATBD, section 4.3
units: 1
valid_max: 9
valid_min: 0
/gt1r/sea_ice_segments/heights/height_segment_confidence: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_confidence
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Confidence level in the surface height estimate based on the number of photons; the background noise rate; and the error analysis
long_name: Surface height confidence
source: ATBD, section 4.2.4.2
units: 1
/gt1r/sea_ice_segments/heights/height_segment_surface_error_est: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_surface_error_est
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Error estimate of the surface height
long_name: h surface error est
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/heights/height_segment_w_gaussian: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_w_gaussian
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: width of best fit gaussian
long_name: width of best fit gaussian
source: ATBD, section 4.2.4
units: meters
/gt1r/sea_ice_segments/heights/height_segment_rms: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/heights/height_segment_rms
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: RMS difference between sea ice modeled and observed photon height distribution
long_name: height rms
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/height_segment_id: Array of 32 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/height_segment_id
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Identifier of each height segment
long_name: Identifier of each height segment
source: ATBD, section 5.2
units: 1
/gt1r/sea_ice_segments/seg_dist_x: Array of 64 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/seg_dist_x
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Along-track distance from the equator crossing to the segment center.
long_name: Along track distance
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/longitude: Array of 64 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/longitude
contentType: referenceInformation
coordinates: delta_time latitude
description: Longitude, WGS84, East=+,Lon of segment center
long_name: Longitude
source: ATBD, section 4.4
standard_name: longitude
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt1r/sea_ice_segments/latitude: Array of 64 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/latitude
contentType: referenceInformation
coordinates: delta_time longitude
description: Latitude, WGS84, North=+, Lat of segment center
long_name: Latitude
source: ATBD, section 4.4
standard_name: latitude
units: degrees_north
valid_max: 90.
valid_min: -90.
/gt1r/sea_ice_segments/geophysical/height_segment_t2m: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_t2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Temperature at 2m above the displacement height (K)
long_name: temperature_at_2m
source: ATL09
standard_name: temperature
units: K
/gt1r/sea_ice_segments/geophysical/height_segment_dac: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_dac
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect.
long_name: Dynamic Atmosphere Correction
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_ps: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_ps
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Sea Level Pressure (Pa)
long_name: sea level pressure
source: ATL09
standard_name: pressure
units: Pa
/gt1r/sea_ice_segments/geophysical/height_segment_ib: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_ib
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Inverted barometer effect calculated from surface pressure
long_name: Inverted barometer effect
source: ATBD, section 4.2
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_load: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_load
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
long_name: Load Tide
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_geoid: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_geoid
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Geoid height above WGS-84 reference ellipsoid (range -107 to 86m), based on the EGM2008 model.
long_name: EGM2008 Geoid
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_ocean: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_ocean
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium)
long_name: Ocean Tide
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_v2m: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_v2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Northward wind at 2m above the displacement height (m/s-1)
long_name: Northward_wind_at_2m
source: ATL09
standard_name: northward_wind
units: m s-1
/gt1r/sea_ice_segments/geophysical/height_segment_mss: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_mss
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean sea surface height above WGS-84 reference ellipsoid (range: -105 to 87m), based on the DTU13 model.
long_name: DTU13 Mean Sea Surface
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_u2m: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_u2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Eastward wind at 2m above the displacement height (m/s-1)
long_name: Eastward_wind_at_2m
source: ATL09
standard_name: eastward_wind
units: m s-1
/gt1r/sea_ice_segments/geophysical/height_segment_lpe: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_lpe
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). (dependent only on time and latitude)
long_name: Equilibrium Tide
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_earth: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_earth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Solid Earth Tide
long_name: Earth Tide
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geophysical/height_segment_pole: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geophysical/height_segment_pole
coordinates: ../delta_time ../latitude ../longitude
description: Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
long_name: Pole Tide
source: Sea Ice ATBD
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt1r/sea_ice_segments/geoseg_beg: Array of 32 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geoseg_beg
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the first photon used in this sea ice segment
long_name: Beginning GEOSEG
source: Sea Ice ATBD
units: 1
/gt1r/sea_ice_segments/delta_time: Array of 64 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/delta_time
contentType: physicalMeasurement
coordinates: latitude longitude
description: 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.
long_name: Elapsed GPS seconds
source: telemetry
standard_name: time
units: seconds since 2018-01-01
CLASS: DIMENSION_SCALE
NAME: gt1r/sea_ice_segments/delta_time
/gt1r/sea_ice_segments/stats/msw_flag: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/msw_flag
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Multiple Scattering warning flag. The multiple scattering warning flag (ATL09 parameter msw_flag) has values from -1 to 5 where zero means no multiple scattering and 5 the greatest. If no layers were detected, then msw_flag = 0. If blowing snow is detected and its estimated optical depth is greater than or equal to 0.5, then msw_flag = 5. If the blowing snow optical depth is less than 0.5, then msw_flag = 4. If no blowing snow is detected but there are cloud or aerosol layers detected, the msw_flag assumes values of 1 to 3 based on the height of the bottom of the lowest layer: < 1 km, msw_flag = 3; 1-3 km, msw_flag = 2; > 3km, msw_flag = 1. A value of -1 indicates that the signal to noise of the data was too low to reliably ascertain the presence of cloud or blowing snow. We expect values of -1 to occur only during daylight.
flag_meanings: cannot_determine no_layers layer_gt_3km layer_between_1_and_3_km layer_lt_1km blow_snow_od_lt_0.5 blow_snow_od_gt_0.5
flag_values: -1, 0, 1, 2, 3, 4, 5
long_name: Multiple Scattering Warning Flag
source: Atmosphere ATBD
units: 1
valid_max: 5
valid_min: -1
/gt1r/sea_ice_segments/stats/hist_median_h: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_median_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Median of the n_fit_photons heights
long_name: trimmed photon heights median
source: ATBD, section 4.2.3.1
units: meters
/gt1r/sea_ice_segments/stats/height_filter_min: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/height_filter_min
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height minimum used in the ssh height filter
long_name: Height Filter Min
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1r/sea_ice_segments/stats/cloud_flag_atm: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/cloud_flag_atm
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Number of layers found from the backscatter profile using the DDA layer finder.
long_name: Cloud Flag Atm
source: Atmosphere ATBD
units: 1
valid_max: 10
valid_min: 0
/gt1r/sea_ice_segments/stats/fpb_avg_dt: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/fpb_avg_dt
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction average dead time
long_name: fpb correction average deadtime
source: Sea Ice ATBD
units: ns
/gt1r/sea_ice_segments/stats/ds_si_hist_bins: Array of 32 bit Integers [ = 0..220]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/ds_si_hist_bins
CLASS: DIMENSION_SCALE
NAME: ds_si_hist_bins
contentType: auxiliaryInformation
description: Dimension scale indexing the sea ice histogram bins. The bin heights must be computed from information contained within the same group as the histogram.
long_name: Sea Ice Histogram Bins Dimension Scale
source: SeaIce ATBD
units: 1
/gt1r/sea_ice_segments/stats/fpb_strength: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/fpb_strength
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction strength
long_name: fpb correction strength
source: Sea Ice ATBD
units: photons/shot
/gt1r/sea_ice_segments/stats/bsnow_con: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/bsnow_con
_FillValue: 127
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow confidence
long_name: Blowing snow confidence
source: ATL09
units: 1
/gt1r/sea_ice_segments/stats/layer_flag: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/layer_flag
contentType: qualityInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
flag_meanings: likely_clear likely_cloudy
flag_values: 0, 1
long_name: Consolidated cloud flag
source: Atmosphere ATBD
units: 1
valid_max: 1
valid_min: 0
/gt1r/sea_ice_segments/stats/hist_photon_bin_size: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_photon_bin_size
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: bin size of photon height histogram
long_name: height histogram bin size
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/backgr_calc: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/backgr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Calculated background count rate based on sun angle, surface slope, unit reflectance
long_name: background count rate calculated
source: ATBD, section 4.2.3
units: hz
/gt1r/sea_ice_segments/stats/fpb_corr: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/fpb_corr
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated first-photon bias(fpb) correction to mean segment height
long_name: first photon bias correction
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/stats/bsnow_h: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/bsnow_h
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow layer top height
long_name: Blowing snow top h
source: ATL09
units: meters
/gt1r/sea_ice_segments/stats/hist_photon_bottom: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_photon_bottom
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: lower bound of height histogram
long_name: height histogram minimum
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/background_r_norm: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/background_r_norm
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background rate normalized to a fixed solar elevation angle
long_name: Normalized background (50-shot)
source: ATBD section 4.3.1.3
units: hz
/gt1r/sea_ice_segments/stats/exmax_mean_2: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/exmax_mean_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 2
long_name: Exmax Mean 2
source: sea ice ATBD Appendix E
units: meters
/gt1r/sea_ice_segments/stats/background_int_height: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/background_int_height
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: The height of the altimetric range window after subtracting the height span of the signal photon events in the 50-shot span
long_name: Height of column used in background calculation
source: ATBD, section 7.3
units: meters
/gt1r/sea_ice_segments/stats/n_photons_actual: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/n_photons_actual
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons gathered
long_name: Number of photons found for the segment
source: ATBD, section 4.2.2.4
units: 1
/gt1r/sea_ice_segments/stats/ice_conc: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/ice_conc
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: sea ice concentration
long_name: sea ice concentration
source: ATBD, section 3.1.4
units: 1
/gt1r/sea_ice_segments/stats/exmax_stdev_2: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/exmax_stdev_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 2
long_name: Exmax Stdev 2
source: sea ice ATBD Appendix E
units: meters
/gt1r/sea_ice_segments/stats/cloud_flag_asr: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/cloud_flag_asr
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Cloud flag (probability) from apparent surface reflectance. 0=clear with high confidence; 1=clear with medium confidence; 2=clear with low confidence; 3=cloudy with low confidence; 4=cloudy with medium confidence; 5=cloudy with high confidence; 6=unknown
flag_meanings: clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence unknown
flag_values: 0, 1, 2, 3, 4, 5, 6
long_name: Cloud Flag ASR
source: Atmosphere ATBD
units: 1
valid_max: 6
valid_min: 0
/gt1r/sea_ice_segments/stats/exmax_stdev_1: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/exmax_stdev_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 1
long_name: Exmax Stdev 1
source: sea ice ATBD Appendix E
units: meters
/gt1r/sea_ice_segments/stats/fpb_corr_width: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/fpb_corr_width
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction width
long_name: fpb correction width
source: Sea Ice ATBD
units: ns
/gt1r/sea_ice_segments/stats/height_coarse_stdev: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/height_coarse_stdev
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height standard deviation of coarse tracker
long_name: Coarse Height Sdev
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1r/sea_ice_segments/stats/height_filter_05: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/height_filter_05
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height fifth percentile used in the ssh height filter
long_name: Height Filter 5th Percentile
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1r/sea_ice_segments/stats/n_photons_used: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/n_photons_used
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons in the trimmed histogram.
long_name: Number of photons used for fit
source: ATBD, section 4.2.2.4
units: 1
/gt1r/sea_ice_segments/stats/backgr_r_200: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/backgr_r_200
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on ATLAS 50 pulse counts
long_name: Background rate 200 hz
source: ATL09
units: hz
/gt1r/sea_ice_segments/stats/hist_photon_top: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_photon_top
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: upper bound of height histogram
long_name: height histogram maximum
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/hist_w: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_w
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Segment histogram width estimate
long_name: Segment histogram width estimate
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/hist_mean_h: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_mean_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean of the n_fit_photons heights
long_name: photon heights mean
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/height_coarse_mn: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/height_coarse_mn
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height mean of coarse tracker
long_name: Coarse Track Height Mean
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1r/sea_ice_segments/stats/exmax_mean_1: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/exmax_mean_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 1
long_name: Exmax Mean 1
source: sea ice ATBD Appendix E
units: meters
/gt1r/sea_ice_segments/stats/hist_photon_heights: Array of 16 bit Integers [ = 0..280132][ = 0..220]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/hist_photon_heights
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Histogram of the n_fit_photons heights
long_name: photon heights histogram
source: ATBD, section 4.2.2.4
units: 1
/gt1r/sea_ice_segments/stats/trim_height_top: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/trim_height_top
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: maximum height of trimmed photons used in the surface calculation procedure
long_name: maximum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/exmax_mix: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/exmax_mix
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mix ratio
long_name: Exmax Mix
source: sea ice ATBD Appendix E
units: meters
/gt1r/sea_ice_segments/stats/asr_25: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/asr_25
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Apparent surface reflectance at 25 hz, averaged to the sea ice segment.
long_name: Apparent Surface Reflectance 25hz
source: Sea Ice ATBD
units: 1
/gt1r/sea_ice_segments/stats/photon_rate: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/photon_rate
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: photon count rate, averaged over segment
long_name: photon rate
source: ATBD, section 4.2.2.4
units: photons/shot
/gt1r/sea_ice_segments/stats/trim_height_bottom: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/trim_height_bottom
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: minimum height of trimmed photons used in the surface calculation procedure
long_name: minimum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt1r/sea_ice_segments/stats/n_photons_define: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/n_photons_define
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons to gather.
long_name: Number of photons defining the segment
source: ATBD, section 4.2.2.4
units: 1
/gt1r/sea_ice_segments/stats/backgr_r_25: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/stats/backgr_r_25
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on 25 hz atmosphere
long_name: Background rate 25hz
source: ATL09
units: hz
/gt1r/sea_ice_segments/geoseg_end: Array of 32 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geoseg_end
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the last photon used in this sea ice segment
long_name: Ending GEOSEG
source: Sea Ice ATBD
units: 1
/gt1r/sea_ice_segments/geolocation/rgt: Array of 16 bit Integers [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/rgt
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: Reference Ground track
source: Sea Ice ATBD
units: 1
valid_max: 1387
valid_min: 1
/gt1r/sea_ice_segments/geolocation/sigma_lon: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/sigma_lon
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point east longitude: 1- sigma (degrees). Applies to all other photons in the group.
long_name: longitude uncertainty
source: Sea Ice ATBD
units: degrees
/gt1r/sea_ice_segments/geolocation/ref_atm_delay: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/ref_atm_delay
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay, in range, for the reference photon.
long_name: Reference Photon Atm. Path Delay
source: Sea Ice ATBD
units: meters
/gt1r/sea_ice_segments/geolocation/beam_azimuth: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/beam_azimuth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: beam azimuth
source: Sea Ice ATBD
units: degrees_east
/gt1r/sea_ice_segments/geolocation/solar_azimuth: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/solar_azimuth
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: The direction, eastwards from north, of the sun vector as seen by an observer at the laser ground spot.
long_name: solar azimuth
source: Sea Ice ATBD
units: degrees_east
/gt1r/sea_ice_segments/geolocation/ref_atm_delay_derivative: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/ref_atm_delay_derivative
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay derivative with respect to ellipsoid for the reference photon, in meters per meter.
long_name: Derivative of Atm. Path Delay
source: Sea Ice ATBD
units: meters/meter
/gt1r/sea_ice_segments/geolocation/sigma_lat: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/sigma_lat
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point geodetic latitude: 1- sigma (degrees). Applies to all other photons in the group
long_name: latitude uncertainty
source: Sea Ice ATBD
units: 1
/gt1r/sea_ice_segments/geolocation/beam_coelev: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/beam_coelev
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot.
long_name: beam co-elevation
source: Sea Ice ATBD
units: degrees
/gt1r/sea_ice_segments/geolocation/sigma_h: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/sigma_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point ellipsoid height: 1- sigma (m). Error estimates for all other photons in the group are computed with the scale defined below.
long_name: height uncertainty
source: Sea Ice ATBD
units: 1
/gt1r/sea_ice_segments/geolocation/solar_elevation: Array of 32 bit Reals [ = 0..280132]
HDF5_OBJ_FULLPATH: /gt1r/sea_ice_segments/geolocation/solar_elevation
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low precision value, with approximately TBD degree accuracy.
long_name: solar elevation
source: Sea Ice ATBD
units: degrees
/gt2r/sea_ice_segments/heights/height_segment_fit_quality_flag: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_fit_quality_flag
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Flag describing the quality of the results of the along-track fit. (-1=height value is invalid; 1=ngrid_w < wlength/2; 2=ngrid_w >= wlength/2; 3=ngrid_dt < dtlength/2; 4=ngrid_dt >= dtlength/2; 5=ngrid_dt >= (dtlength-2): where 1 is best and 5 is poor). Heights are reported even if this flag indicates the height is invalid.
flag_meanings: invalid best high med low poor
flag_values: -1, 1, 2, 3, 4, 5
long_name: height Quality Flag
source: ATBD, section 4.2.4.2
units: 1
valid_max: 5
valid_min: -1
/gt2r/sea_ice_segments/heights/height_segment_length_seg: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_length_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: along-track length of segment containing n_photons_actual
long_name: length of segment
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/heights/height_segment_asr_calc: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_asr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Computed apparent surface reflectance for the sea ice segment.
long_name: Calculated Apparent Surface Reflectivity
source: Sea Ice ATBD
units: 1
/gt2r/sea_ice_segments/heights/height_segment_quality: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_quality
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Height segment quality flag, 1 is good quality, 0 is bad depending on fit, wguassian, or layer flag
flag_meanings: bad_quality good_quality
flag_values: 0, 1
long_name: Height Segment Quality Flag
source: ATBD, section 4.2.4
units: 1
valid_max: 1
valid_min: 0
/gt2r/sea_ice_segments/heights/height_segment_n_pulse_seg: Array of 32 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_n_pulse_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: number of laser pulses
long_name: number of laser pulses
source: ATBD, section 4.2.2.4
units: 1
/gt2r/sea_ice_segments/heights/across_track_distance: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/across_track_distance
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Across track distance of photons averaged over the sea ice height segment.
long_name: Across Track Distance
source: ATBD, section 4.2.4
units: meters
/gt2r/sea_ice_segments/heights/height_segment_htcorr_skew: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_htcorr_skew
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: height corection for skew
long_name: Height Correction for Skew
source: ATBD, section 4.2.6
units: meters
/gt2r/sea_ice_segments/heights/height_segment_ssh_flag: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_ssh_flag
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Identifies the height segments that are candidates for use as sea surface reference in freeboard calculations in ATL10. 0 = sea ice; 1 = sea surface
flag_meanings: sea_ice sea_surface
flag_values: 0, 1
long_name: Sea Surface Flag
source: ATBD, section 4.3
units: 1
valid_max: 1
valid_min: 0
/gt2r/sea_ice_segments/heights/height_segment_height: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_height
coordinates: ../delta_time ../latitude ../longitude
description: Mean height from along-track segment fit detremined by the sea ice algorithm
long_name: height of segment surface
source: ATBD, section 4.2.2.4
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt2r/sea_ice_segments/heights/height_segment_type: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_type
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Value that indicates segment surface type as sea ice or different types of sea surface. 0=cloud covered: rsurf
flag_meanings: cloud_covered other specular_lead_low_w_bkg specular_lead_low specular_lead_high_w_bkg specular_lead_high dark_lead_smooth_w_bkg dark_lead_smooth dark_lead_rough_w_bkg dark_lead_rough
flag_values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
long_name: Segment surface type
source: ATBD, section 4.3
units: 1
valid_max: 9
valid_min: 0
/gt2r/sea_ice_segments/heights/height_segment_confidence: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_confidence
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Confidence level in the surface height estimate based on the number of photons; the background noise rate; and the error analysis
long_name: Surface height confidence
source: ATBD, section 4.2.4.2
units: 1
/gt2r/sea_ice_segments/heights/height_segment_surface_error_est: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_surface_error_est
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Error estimate of the surface height
long_name: h surface error est
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/heights/height_segment_w_gaussian: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_w_gaussian
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: width of best fit gaussian
long_name: width of best fit gaussian
source: ATBD, section 4.2.4
units: meters
/gt2r/sea_ice_segments/heights/height_segment_rms: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/heights/height_segment_rms
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: RMS difference between sea ice modeled and observed photon height distribution
long_name: height rms
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/height_segment_id: Array of 32 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/height_segment_id
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Identifier of each height segment
long_name: Identifier of each height segment
source: ATBD, section 5.2
units: 1
/gt2r/sea_ice_segments/seg_dist_x: Array of 64 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/seg_dist_x
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Along-track distance from the equator crossing to the segment center.
long_name: Along track distance
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/longitude: Array of 64 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/longitude
contentType: referenceInformation
coordinates: delta_time latitude
description: Longitude, WGS84, East=+,Lon of segment center
long_name: Longitude
source: ATBD, section 4.4
standard_name: longitude
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt2r/sea_ice_segments/latitude: Array of 64 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/latitude
contentType: referenceInformation
coordinates: delta_time longitude
description: Latitude, WGS84, North=+, Lat of segment center
long_name: Latitude
source: ATBD, section 4.4
standard_name: latitude
units: degrees_north
valid_max: 90.
valid_min: -90.
/gt2r/sea_ice_segments/geophysical/height_segment_t2m: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_t2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Temperature at 2m above the displacement height (K)
long_name: temperature_at_2m
source: ATL09
standard_name: temperature
units: K
/gt2r/sea_ice_segments/geophysical/height_segment_dac: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_dac
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect.
long_name: Dynamic Atmosphere Correction
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_ps: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_ps
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Sea Level Pressure (Pa)
long_name: sea level pressure
source: ATL09
standard_name: pressure
units: Pa
/gt2r/sea_ice_segments/geophysical/height_segment_ib: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_ib
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Inverted barometer effect calculated from surface pressure
long_name: Inverted barometer effect
source: ATBD, section 4.2
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_load: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_load
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
long_name: Load Tide
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_geoid: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_geoid
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Geoid height above WGS-84 reference ellipsoid (range -107 to 86m), based on the EGM2008 model.
long_name: EGM2008 Geoid
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_ocean: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_ocean
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium)
long_name: Ocean Tide
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_v2m: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_v2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Northward wind at 2m above the displacement height (m/s-1)
long_name: Northward_wind_at_2m
source: ATL09
standard_name: northward_wind
units: m s-1
/gt2r/sea_ice_segments/geophysical/height_segment_mss: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_mss
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean sea surface height above WGS-84 reference ellipsoid (range: -105 to 87m), based on the DTU13 model.
long_name: DTU13 Mean Sea Surface
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_u2m: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_u2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Eastward wind at 2m above the displacement height (m/s-1)
long_name: Eastward_wind_at_2m
source: ATL09
standard_name: eastward_wind
units: m s-1
/gt2r/sea_ice_segments/geophysical/height_segment_lpe: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_lpe
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). (dependent only on time and latitude)
long_name: Equilibrium Tide
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_earth: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_earth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Solid Earth Tide
long_name: Earth Tide
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geophysical/height_segment_pole: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geophysical/height_segment_pole
coordinates: ../delta_time ../latitude ../longitude
description: Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
long_name: Pole Tide
source: Sea Ice ATBD
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt2r/sea_ice_segments/geoseg_beg: Array of 32 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geoseg_beg
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the first photon used in this sea ice segment
long_name: Beginning GEOSEG
source: Sea Ice ATBD
units: 1
/gt2r/sea_ice_segments/delta_time: Array of 64 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/delta_time
contentType: physicalMeasurement
coordinates: latitude longitude
description: 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.
long_name: Elapsed GPS seconds
source: telemetry
standard_name: time
units: seconds since 2018-01-01
CLASS: DIMENSION_SCALE
NAME: gt2r/sea_ice_segments/delta_time
/gt2r/sea_ice_segments/stats/msw_flag: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/msw_flag
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Multiple Scattering warning flag. The multiple scattering warning flag (ATL09 parameter msw_flag) has values from -1 to 5 where zero means no multiple scattering and 5 the greatest. If no layers were detected, then msw_flag = 0. If blowing snow is detected and its estimated optical depth is greater than or equal to 0.5, then msw_flag = 5. If the blowing snow optical depth is less than 0.5, then msw_flag = 4. If no blowing snow is detected but there are cloud or aerosol layers detected, the msw_flag assumes values of 1 to 3 based on the height of the bottom of the lowest layer: < 1 km, msw_flag = 3; 1-3 km, msw_flag = 2; > 3km, msw_flag = 1. A value of -1 indicates that the signal to noise of the data was too low to reliably ascertain the presence of cloud or blowing snow. We expect values of -1 to occur only during daylight.
flag_meanings: cannot_determine no_layers layer_gt_3km layer_between_1_and_3_km layer_lt_1km blow_snow_od_lt_0.5 blow_snow_od_gt_0.5
flag_values: -1, 0, 1, 2, 3, 4, 5
long_name: Multiple Scattering Warning Flag
source: Atmosphere ATBD
units: 1
valid_max: 5
valid_min: -1
/gt2r/sea_ice_segments/stats/hist_median_h: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_median_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Median of the n_fit_photons heights
long_name: trimmed photon heights median
source: ATBD, section 4.2.3.1
units: meters
/gt2r/sea_ice_segments/stats/height_filter_min: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/height_filter_min
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height minimum used in the ssh height filter
long_name: Height Filter Min
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2r/sea_ice_segments/stats/cloud_flag_atm: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/cloud_flag_atm
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Number of layers found from the backscatter profile using the DDA layer finder.
long_name: Cloud Flag Atm
source: Atmosphere ATBD
units: 1
valid_max: 10
valid_min: 0
/gt2r/sea_ice_segments/stats/fpb_avg_dt: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/fpb_avg_dt
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction average dead time
long_name: fpb correction average deadtime
source: Sea Ice ATBD
units: ns
/gt2r/sea_ice_segments/stats/ds_si_hist_bins: Array of 32 bit Integers [ = 0..220]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/ds_si_hist_bins
CLASS: DIMENSION_SCALE
NAME: ds_si_hist_bins
contentType: auxiliaryInformation
description: Dimension scale indexing the sea ice histogram bins. The bin heights must be computed from information contained within the same group as the histogram.
long_name: Sea Ice Histogram Bins Dimension Scale
source: SeaIce ATBD
units: 1
/gt2r/sea_ice_segments/stats/fpb_strength: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/fpb_strength
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction strength
long_name: fpb correction strength
source: Sea Ice ATBD
units: photons/shot
/gt2r/sea_ice_segments/stats/bsnow_con: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/bsnow_con
_FillValue: 127
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow confidence
long_name: Blowing snow confidence
source: ATL09
units: 1
/gt2r/sea_ice_segments/stats/layer_flag: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/layer_flag
contentType: qualityInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
flag_meanings: likely_clear likely_cloudy
flag_values: 0, 1
long_name: Consolidated cloud flag
source: Atmosphere ATBD
units: 1
valid_max: 1
valid_min: 0
/gt2r/sea_ice_segments/stats/hist_photon_bin_size: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_photon_bin_size
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: bin size of photon height histogram
long_name: height histogram bin size
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/backgr_calc: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/backgr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Calculated background count rate based on sun angle, surface slope, unit reflectance
long_name: background count rate calculated
source: ATBD, section 4.2.3
units: hz
/gt2r/sea_ice_segments/stats/fpb_corr: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/fpb_corr
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated first-photon bias(fpb) correction to mean segment height
long_name: first photon bias correction
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/stats/bsnow_h: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/bsnow_h
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow layer top height
long_name: Blowing snow top h
source: ATL09
units: meters
/gt2r/sea_ice_segments/stats/hist_photon_bottom: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_photon_bottom
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: lower bound of height histogram
long_name: height histogram minimum
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/background_r_norm: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/background_r_norm
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background rate normalized to a fixed solar elevation angle
long_name: Normalized background (50-shot)
source: ATBD section 4.3.1.3
units: hz
/gt2r/sea_ice_segments/stats/exmax_mean_2: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/exmax_mean_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 2
long_name: Exmax Mean 2
source: sea ice ATBD Appendix E
units: meters
/gt2r/sea_ice_segments/stats/background_int_height: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/background_int_height
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: The height of the altimetric range window after subtracting the height span of the signal photon events in the 50-shot span
long_name: Height of column used in background calculation
source: ATBD, section 7.3
units: meters
/gt2r/sea_ice_segments/stats/n_photons_actual: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/n_photons_actual
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons gathered
long_name: Number of photons found for the segment
source: ATBD, section 4.2.2.4
units: 1
/gt2r/sea_ice_segments/stats/ice_conc: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/ice_conc
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: sea ice concentration
long_name: sea ice concentration
source: ATBD, section 3.1.4
units: 1
/gt2r/sea_ice_segments/stats/exmax_stdev_2: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/exmax_stdev_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 2
long_name: Exmax Stdev 2
source: sea ice ATBD Appendix E
units: meters
/gt2r/sea_ice_segments/stats/cloud_flag_asr: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/cloud_flag_asr
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Cloud flag (probability) from apparent surface reflectance. 0=clear with high confidence; 1=clear with medium confidence; 2=clear with low confidence; 3=cloudy with low confidence; 4=cloudy with medium confidence; 5=cloudy with high confidence; 6=unknown
flag_meanings: clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence unknown
flag_values: 0, 1, 2, 3, 4, 5, 6
long_name: Cloud Flag ASR
source: Atmosphere ATBD
units: 1
valid_max: 6
valid_min: 0
/gt2r/sea_ice_segments/stats/exmax_stdev_1: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/exmax_stdev_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 1
long_name: Exmax Stdev 1
source: sea ice ATBD Appendix E
units: meters
/gt2r/sea_ice_segments/stats/fpb_corr_width: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/fpb_corr_width
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction width
long_name: fpb correction width
source: Sea Ice ATBD
units: ns
/gt2r/sea_ice_segments/stats/height_coarse_stdev: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/height_coarse_stdev
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height standard deviation of coarse tracker
long_name: Coarse Height Sdev
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2r/sea_ice_segments/stats/height_filter_05: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/height_filter_05
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height fifth percentile used in the ssh height filter
long_name: Height Filter 5th Percentile
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2r/sea_ice_segments/stats/n_photons_used: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/n_photons_used
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons in the trimmed histogram.
long_name: Number of photons used for fit
source: ATBD, section 4.2.2.4
units: 1
/gt2r/sea_ice_segments/stats/backgr_r_200: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/backgr_r_200
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on ATLAS 50 pulse counts
long_name: Background rate 200 hz
source: ATL09
units: hz
/gt2r/sea_ice_segments/stats/hist_photon_top: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_photon_top
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: upper bound of height histogram
long_name: height histogram maximum
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/hist_w: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_w
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Segment histogram width estimate
long_name: Segment histogram width estimate
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/hist_mean_h: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_mean_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean of the n_fit_photons heights
long_name: photon heights mean
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/height_coarse_mn: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/height_coarse_mn
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height mean of coarse tracker
long_name: Coarse Track Height Mean
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2r/sea_ice_segments/stats/exmax_mean_1: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/exmax_mean_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 1
long_name: Exmax Mean 1
source: sea ice ATBD Appendix E
units: meters
/gt2r/sea_ice_segments/stats/hist_photon_heights: Array of 16 bit Integers [ = 0..225002][ = 0..220]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/hist_photon_heights
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Histogram of the n_fit_photons heights
long_name: photon heights histogram
source: ATBD, section 4.2.2.4
units: 1
/gt2r/sea_ice_segments/stats/trim_height_top: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/trim_height_top
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: maximum height of trimmed photons used in the surface calculation procedure
long_name: maximum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/exmax_mix: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/exmax_mix
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mix ratio
long_name: Exmax Mix
source: sea ice ATBD Appendix E
units: meters
/gt2r/sea_ice_segments/stats/asr_25: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/asr_25
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Apparent surface reflectance at 25 hz, averaged to the sea ice segment.
long_name: Apparent Surface Reflectance 25hz
source: Sea Ice ATBD
units: 1
/gt2r/sea_ice_segments/stats/photon_rate: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/photon_rate
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: photon count rate, averaged over segment
long_name: photon rate
source: ATBD, section 4.2.2.4
units: photons/shot
/gt2r/sea_ice_segments/stats/trim_height_bottom: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/trim_height_bottom
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: minimum height of trimmed photons used in the surface calculation procedure
long_name: minimum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt2r/sea_ice_segments/stats/n_photons_define: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/n_photons_define
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons to gather.
long_name: Number of photons defining the segment
source: ATBD, section 4.2.2.4
units: 1
/gt2r/sea_ice_segments/stats/backgr_r_25: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/stats/backgr_r_25
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on 25 hz atmosphere
long_name: Background rate 25hz
source: ATL09
units: hz
/gt2r/sea_ice_segments/geoseg_end: Array of 32 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geoseg_end
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the last photon used in this sea ice segment
long_name: Ending GEOSEG
source: Sea Ice ATBD
units: 1
/gt2r/sea_ice_segments/geolocation/rgt: Array of 16 bit Integers [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/rgt
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: Reference Ground track
source: Sea Ice ATBD
units: 1
valid_max: 1387
valid_min: 1
/gt2r/sea_ice_segments/geolocation/sigma_lon: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/sigma_lon
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point east longitude: 1- sigma (degrees). Applies to all other photons in the group.
long_name: longitude uncertainty
source: Sea Ice ATBD
units: degrees
/gt2r/sea_ice_segments/geolocation/ref_atm_delay: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/ref_atm_delay
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay, in range, for the reference photon.
long_name: Reference Photon Atm. Path Delay
source: Sea Ice ATBD
units: meters
/gt2r/sea_ice_segments/geolocation/beam_azimuth: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/beam_azimuth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: beam azimuth
source: Sea Ice ATBD
units: degrees_east
/gt2r/sea_ice_segments/geolocation/solar_azimuth: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/solar_azimuth
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: The direction, eastwards from north, of the sun vector as seen by an observer at the laser ground spot.
long_name: solar azimuth
source: Sea Ice ATBD
units: degrees_east
/gt2r/sea_ice_segments/geolocation/ref_atm_delay_derivative: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/ref_atm_delay_derivative
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay derivative with respect to ellipsoid for the reference photon, in meters per meter.
long_name: Derivative of Atm. Path Delay
source: Sea Ice ATBD
units: meters/meter
/gt2r/sea_ice_segments/geolocation/sigma_lat: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/sigma_lat
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point geodetic latitude: 1- sigma (degrees). Applies to all other photons in the group
long_name: latitude uncertainty
source: Sea Ice ATBD
units: 1
/gt2r/sea_ice_segments/geolocation/beam_coelev: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/beam_coelev
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot.
long_name: beam co-elevation
source: Sea Ice ATBD
units: degrees
/gt2r/sea_ice_segments/geolocation/sigma_h: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/sigma_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point ellipsoid height: 1- sigma (m). Error estimates for all other photons in the group are computed with the scale defined below.
long_name: height uncertainty
source: Sea Ice ATBD
units: 1
/gt2r/sea_ice_segments/geolocation/solar_elevation: Array of 32 bit Reals [ = 0..225002]
HDF5_OBJ_FULLPATH: /gt2r/sea_ice_segments/geolocation/solar_elevation
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low precision value, with approximately TBD degree accuracy.
long_name: solar elevation
source: Sea Ice ATBD
units: degrees
/gt1l/sea_ice_segments/heights/height_segment_fit_quality_flag: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_fit_quality_flag
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Flag describing the quality of the results of the along-track fit. (-1=height value is invalid; 1=ngrid_w < wlength/2; 2=ngrid_w >= wlength/2; 3=ngrid_dt < dtlength/2; 4=ngrid_dt >= dtlength/2; 5=ngrid_dt >= (dtlength-2): where 1 is best and 5 is poor). Heights are reported even if this flag indicates the height is invalid.
flag_meanings: invalid best high med low poor
flag_values: -1, 1, 2, 3, 4, 5
long_name: height Quality Flag
source: ATBD, section 4.2.4.2
units: 1
valid_max: 5
valid_min: -1
/gt1l/sea_ice_segments/heights/height_segment_length_seg: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_length_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: along-track length of segment containing n_photons_actual
long_name: length of segment
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/heights/height_segment_asr_calc: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_asr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Computed apparent surface reflectance for the sea ice segment.
long_name: Calculated Apparent Surface Reflectivity
source: Sea Ice ATBD
units: 1
/gt1l/sea_ice_segments/heights/height_segment_quality: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_quality
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Height segment quality flag, 1 is good quality, 0 is bad depending on fit, wguassian, or layer flag
flag_meanings: bad_quality good_quality
flag_values: 0, 1
long_name: Height Segment Quality Flag
source: ATBD, section 4.2.4
units: 1
valid_max: 1
valid_min: 0
/gt1l/sea_ice_segments/heights/height_segment_n_pulse_seg: Array of 32 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_n_pulse_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: number of laser pulses
long_name: number of laser pulses
source: ATBD, section 4.2.2.4
units: 1
/gt1l/sea_ice_segments/heights/across_track_distance: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/across_track_distance
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Across track distance of photons averaged over the sea ice height segment.
long_name: Across Track Distance
source: ATBD, section 4.2.4
units: meters
/gt1l/sea_ice_segments/heights/height_segment_htcorr_skew: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_htcorr_skew
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: height corection for skew
long_name: Height Correction for Skew
source: ATBD, section 4.2.6
units: meters
/gt1l/sea_ice_segments/heights/height_segment_ssh_flag: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_ssh_flag
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Identifies the height segments that are candidates for use as sea surface reference in freeboard calculations in ATL10. 0 = sea ice; 1 = sea surface
flag_meanings: sea_ice sea_surface
flag_values: 0, 1
long_name: Sea Surface Flag
source: ATBD, section 4.3
units: 1
valid_max: 1
valid_min: 0
/gt1l/sea_ice_segments/heights/height_segment_height: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_height
coordinates: ../delta_time ../latitude ../longitude
description: Mean height from along-track segment fit detremined by the sea ice algorithm
long_name: height of segment surface
source: ATBD, section 4.2.2.4
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt1l/sea_ice_segments/heights/height_segment_type: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_type
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Value that indicates segment surface type as sea ice or different types of sea surface. 0=cloud covered: rsurf
flag_meanings: cloud_covered other specular_lead_low_w_bkg specular_lead_low specular_lead_high_w_bkg specular_lead_high dark_lead_smooth_w_bkg dark_lead_smooth dark_lead_rough_w_bkg dark_lead_rough
flag_values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
long_name: Segment surface type
source: ATBD, section 4.3
units: 1
valid_max: 9
valid_min: 0
/gt1l/sea_ice_segments/heights/height_segment_confidence: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_confidence
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Confidence level in the surface height estimate based on the number of photons; the background noise rate; and the error analysis
long_name: Surface height confidence
source: ATBD, section 4.2.4.2
units: 1
/gt1l/sea_ice_segments/heights/height_segment_surface_error_est: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_surface_error_est
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Error estimate of the surface height
long_name: h surface error est
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/heights/height_segment_w_gaussian: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_w_gaussian
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: width of best fit gaussian
long_name: width of best fit gaussian
source: ATBD, section 4.2.4
units: meters
/gt1l/sea_ice_segments/heights/height_segment_rms: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/heights/height_segment_rms
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: RMS difference between sea ice modeled and observed photon height distribution
long_name: height rms
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/height_segment_id: Array of 32 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/height_segment_id
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Identifier of each height segment
long_name: Identifier of each height segment
source: ATBD, section 5.2
units: 1
/gt1l/sea_ice_segments/seg_dist_x: Array of 64 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/seg_dist_x
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Along-track distance from the equator crossing to the segment center.
long_name: Along track distance
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/longitude: Array of 64 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/longitude
contentType: referenceInformation
coordinates: delta_time latitude
description: Longitude, WGS84, East=+,Lon of segment center
long_name: Longitude
source: ATBD, section 4.4
standard_name: longitude
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt1l/sea_ice_segments/latitude: Array of 64 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/latitude
contentType: referenceInformation
coordinates: delta_time longitude
description: Latitude, WGS84, North=+, Lat of segment center
long_name: Latitude
source: ATBD, section 4.4
standard_name: latitude
units: degrees_north
valid_max: 90.
valid_min: -90.
/gt1l/sea_ice_segments/geophysical/height_segment_t2m: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_t2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Temperature at 2m above the displacement height (K)
long_name: temperature_at_2m
source: ATL09
standard_name: temperature
units: K
/gt1l/sea_ice_segments/geophysical/height_segment_dac: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_dac
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect.
long_name: Dynamic Atmosphere Correction
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_ps: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_ps
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Sea Level Pressure (Pa)
long_name: sea level pressure
source: ATL09
standard_name: pressure
units: Pa
/gt1l/sea_ice_segments/geophysical/height_segment_ib: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_ib
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Inverted barometer effect calculated from surface pressure
long_name: Inverted barometer effect
source: ATBD, section 4.2
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_load: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_load
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
long_name: Load Tide
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_geoid: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_geoid
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Geoid height above WGS-84 reference ellipsoid (range -107 to 86m), based on the EGM2008 model.
long_name: EGM2008 Geoid
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_ocean: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_ocean
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium)
long_name: Ocean Tide
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_v2m: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_v2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Northward wind at 2m above the displacement height (m/s-1)
long_name: Northward_wind_at_2m
source: ATL09
standard_name: northward_wind
units: m s-1
/gt1l/sea_ice_segments/geophysical/height_segment_mss: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_mss
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean sea surface height above WGS-84 reference ellipsoid (range: -105 to 87m), based on the DTU13 model.
long_name: DTU13 Mean Sea Surface
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_u2m: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_u2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Eastward wind at 2m above the displacement height (m/s-1)
long_name: Eastward_wind_at_2m
source: ATL09
standard_name: eastward_wind
units: m s-1
/gt1l/sea_ice_segments/geophysical/height_segment_lpe: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_lpe
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). (dependent only on time and latitude)
long_name: Equilibrium Tide
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_earth: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_earth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Solid Earth Tide
long_name: Earth Tide
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geophysical/height_segment_pole: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geophysical/height_segment_pole
coordinates: ../delta_time ../latitude ../longitude
description: Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
long_name: Pole Tide
source: Sea Ice ATBD
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt1l/sea_ice_segments/geoseg_beg: Array of 32 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geoseg_beg
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the first photon used in this sea ice segment
long_name: Beginning GEOSEG
source: Sea Ice ATBD
units: 1
/gt1l/sea_ice_segments/delta_time: Array of 64 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/delta_time
contentType: physicalMeasurement
coordinates: latitude longitude
description: 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.
long_name: Elapsed GPS seconds
source: telemetry
standard_name: time
units: seconds since 2018-01-01
CLASS: DIMENSION_SCALE
NAME: gt1l/sea_ice_segments/delta_time
/gt1l/sea_ice_segments/stats/msw_flag: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/msw_flag
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Multiple Scattering warning flag. The multiple scattering warning flag (ATL09 parameter msw_flag) has values from -1 to 5 where zero means no multiple scattering and 5 the greatest. If no layers were detected, then msw_flag = 0. If blowing snow is detected and its estimated optical depth is greater than or equal to 0.5, then msw_flag = 5. If the blowing snow optical depth is less than 0.5, then msw_flag = 4. If no blowing snow is detected but there are cloud or aerosol layers detected, the msw_flag assumes values of 1 to 3 based on the height of the bottom of the lowest layer: < 1 km, msw_flag = 3; 1-3 km, msw_flag = 2; > 3km, msw_flag = 1. A value of -1 indicates that the signal to noise of the data was too low to reliably ascertain the presence of cloud or blowing snow. We expect values of -1 to occur only during daylight.
flag_meanings: cannot_determine no_layers layer_gt_3km layer_between_1_and_3_km layer_lt_1km blow_snow_od_lt_0.5 blow_snow_od_gt_0.5
flag_values: -1, 0, 1, 2, 3, 4, 5
long_name: Multiple Scattering Warning Flag
source: Atmosphere ATBD
units: 1
valid_max: 5
valid_min: -1
/gt1l/sea_ice_segments/stats/hist_median_h: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_median_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Median of the n_fit_photons heights
long_name: trimmed photon heights median
source: ATBD, section 4.2.3.1
units: meters
/gt1l/sea_ice_segments/stats/height_filter_min: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/height_filter_min
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height minimum used in the ssh height filter
long_name: Height Filter Min
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1l/sea_ice_segments/stats/cloud_flag_atm: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/cloud_flag_atm
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Number of layers found from the backscatter profile using the DDA layer finder.
long_name: Cloud Flag Atm
source: Atmosphere ATBD
units: 1
valid_max: 10
valid_min: 0
/gt1l/sea_ice_segments/stats/fpb_avg_dt: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/fpb_avg_dt
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction average dead time
long_name: fpb correction average deadtime
source: Sea Ice ATBD
units: ns
/gt1l/sea_ice_segments/stats/ds_si_hist_bins: Array of 32 bit Integers [ = 0..220]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/ds_si_hist_bins
CLASS: DIMENSION_SCALE
NAME: ds_si_hist_bins
contentType: auxiliaryInformation
description: Dimension scale indexing the sea ice histogram bins. The bin heights must be computed from information contained within the same group as the histogram.
long_name: Sea Ice Histogram Bins Dimension Scale
source: SeaIce ATBD
units: 1
/gt1l/sea_ice_segments/stats/fpb_strength: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/fpb_strength
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction strength
long_name: fpb correction strength
source: Sea Ice ATBD
units: photons/shot
/gt1l/sea_ice_segments/stats/bsnow_con: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/bsnow_con
_FillValue: 127
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow confidence
long_name: Blowing snow confidence
source: ATL09
units: 1
/gt1l/sea_ice_segments/stats/layer_flag: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/layer_flag
contentType: qualityInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
flag_meanings: likely_clear likely_cloudy
flag_values: 0, 1
long_name: Consolidated cloud flag
source: Atmosphere ATBD
units: 1
valid_max: 1
valid_min: 0
/gt1l/sea_ice_segments/stats/hist_photon_bin_size: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_photon_bin_size
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: bin size of photon height histogram
long_name: height histogram bin size
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/backgr_calc: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/backgr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Calculated background count rate based on sun angle, surface slope, unit reflectance
long_name: background count rate calculated
source: ATBD, section 4.2.3
units: hz
/gt1l/sea_ice_segments/stats/fpb_corr: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/fpb_corr
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated first-photon bias(fpb) correction to mean segment height
long_name: first photon bias correction
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/stats/bsnow_h: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/bsnow_h
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow layer top height
long_name: Blowing snow top h
source: ATL09
units: meters
/gt1l/sea_ice_segments/stats/hist_photon_bottom: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_photon_bottom
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: lower bound of height histogram
long_name: height histogram minimum
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/background_r_norm: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/background_r_norm
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background rate normalized to a fixed solar elevation angle
long_name: Normalized background (50-shot)
source: ATBD section 4.3.1.3
units: hz
/gt1l/sea_ice_segments/stats/exmax_mean_2: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/exmax_mean_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 2
long_name: Exmax Mean 2
source: sea ice ATBD Appendix E
units: meters
/gt1l/sea_ice_segments/stats/background_int_height: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/background_int_height
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: The height of the altimetric range window after subtracting the height span of the signal photon events in the 50-shot span
long_name: Height of column used in background calculation
source: ATBD, section 7.3
units: meters
/gt1l/sea_ice_segments/stats/n_photons_actual: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/n_photons_actual
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons gathered
long_name: Number of photons found for the segment
source: ATBD, section 4.2.2.4
units: 1
/gt1l/sea_ice_segments/stats/ice_conc: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/ice_conc
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: sea ice concentration
long_name: sea ice concentration
source: ATBD, section 3.1.4
units: 1
/gt1l/sea_ice_segments/stats/exmax_stdev_2: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/exmax_stdev_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 2
long_name: Exmax Stdev 2
source: sea ice ATBD Appendix E
units: meters
/gt1l/sea_ice_segments/stats/cloud_flag_asr: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/cloud_flag_asr
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Cloud flag (probability) from apparent surface reflectance. 0=clear with high confidence; 1=clear with medium confidence; 2=clear with low confidence; 3=cloudy with low confidence; 4=cloudy with medium confidence; 5=cloudy with high confidence; 6=unknown
flag_meanings: clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence unknown
flag_values: 0, 1, 2, 3, 4, 5, 6
long_name: Cloud Flag ASR
source: Atmosphere ATBD
units: 1
valid_max: 6
valid_min: 0
/gt1l/sea_ice_segments/stats/exmax_stdev_1: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/exmax_stdev_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 1
long_name: Exmax Stdev 1
source: sea ice ATBD Appendix E
units: meters
/gt1l/sea_ice_segments/stats/fpb_corr_width: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/fpb_corr_width
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction width
long_name: fpb correction width
source: Sea Ice ATBD
units: ns
/gt1l/sea_ice_segments/stats/height_coarse_stdev: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/height_coarse_stdev
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height standard deviation of coarse tracker
long_name: Coarse Height Sdev
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1l/sea_ice_segments/stats/height_filter_05: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/height_filter_05
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height fifth percentile used in the ssh height filter
long_name: Height Filter 5th Percentile
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1l/sea_ice_segments/stats/n_photons_used: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/n_photons_used
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons in the trimmed histogram.
long_name: Number of photons used for fit
source: ATBD, section 4.2.2.4
units: 1
/gt1l/sea_ice_segments/stats/backgr_r_200: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/backgr_r_200
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on ATLAS 50 pulse counts
long_name: Background rate 200 hz
source: ATL09
units: hz
/gt1l/sea_ice_segments/stats/hist_photon_top: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_photon_top
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: upper bound of height histogram
long_name: height histogram maximum
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/hist_w: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_w
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Segment histogram width estimate
long_name: Segment histogram width estimate
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/hist_mean_h: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_mean_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean of the n_fit_photons heights
long_name: photon heights mean
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/height_coarse_mn: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/height_coarse_mn
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height mean of coarse tracker
long_name: Coarse Track Height Mean
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt1l/sea_ice_segments/stats/exmax_mean_1: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/exmax_mean_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 1
long_name: Exmax Mean 1
source: sea ice ATBD Appendix E
units: meters
/gt1l/sea_ice_segments/stats/hist_photon_heights: Array of 16 bit Integers [ = 0..276542][ = 0..220]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/hist_photon_heights
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Histogram of the n_fit_photons heights
long_name: photon heights histogram
source: ATBD, section 4.2.2.4
units: 1
/gt1l/sea_ice_segments/stats/trim_height_top: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/trim_height_top
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: maximum height of trimmed photons used in the surface calculation procedure
long_name: maximum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/exmax_mix: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/exmax_mix
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mix ratio
long_name: Exmax Mix
source: sea ice ATBD Appendix E
units: meters
/gt1l/sea_ice_segments/stats/asr_25: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/asr_25
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Apparent surface reflectance at 25 hz, averaged to the sea ice segment.
long_name: Apparent Surface Reflectance 25hz
source: Sea Ice ATBD
units: 1
/gt1l/sea_ice_segments/stats/photon_rate: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/photon_rate
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: photon count rate, averaged over segment
long_name: photon rate
source: ATBD, section 4.2.2.4
units: photons/shot
/gt1l/sea_ice_segments/stats/trim_height_bottom: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/trim_height_bottom
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: minimum height of trimmed photons used in the surface calculation procedure
long_name: minimum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt1l/sea_ice_segments/stats/n_photons_define: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/n_photons_define
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons to gather.
long_name: Number of photons defining the segment
source: ATBD, section 4.2.2.4
units: 1
/gt1l/sea_ice_segments/stats/backgr_r_25: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/stats/backgr_r_25
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on 25 hz atmosphere
long_name: Background rate 25hz
source: ATL09
units: hz
/gt1l/sea_ice_segments/geoseg_end: Array of 32 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geoseg_end
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the last photon used in this sea ice segment
long_name: Ending GEOSEG
source: Sea Ice ATBD
units: 1
/gt1l/sea_ice_segments/geolocation/rgt: Array of 16 bit Integers [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/rgt
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: Reference Ground track
source: Sea Ice ATBD
units: 1
valid_max: 1387
valid_min: 1
/gt1l/sea_ice_segments/geolocation/sigma_lon: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/sigma_lon
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point east longitude: 1- sigma (degrees). Applies to all other photons in the group.
long_name: longitude uncertainty
source: Sea Ice ATBD
units: degrees
/gt1l/sea_ice_segments/geolocation/ref_atm_delay: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/ref_atm_delay
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay, in range, for the reference photon.
long_name: Reference Photon Atm. Path Delay
source: Sea Ice ATBD
units: meters
/gt1l/sea_ice_segments/geolocation/beam_azimuth: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/beam_azimuth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: beam azimuth
source: Sea Ice ATBD
units: degrees_east
/gt1l/sea_ice_segments/geolocation/solar_azimuth: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/solar_azimuth
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: The direction, eastwards from north, of the sun vector as seen by an observer at the laser ground spot.
long_name: solar azimuth
source: Sea Ice ATBD
units: degrees_east
/gt1l/sea_ice_segments/geolocation/ref_atm_delay_derivative: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/ref_atm_delay_derivative
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay derivative with respect to ellipsoid for the reference photon, in meters per meter.
long_name: Derivative of Atm. Path Delay
source: Sea Ice ATBD
units: meters/meter
/gt1l/sea_ice_segments/geolocation/sigma_lat: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/sigma_lat
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point geodetic latitude: 1- sigma (degrees). Applies to all other photons in the group
long_name: latitude uncertainty
source: Sea Ice ATBD
units: 1
/gt1l/sea_ice_segments/geolocation/beam_coelev: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/beam_coelev
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot.
long_name: beam co-elevation
source: Sea Ice ATBD
units: degrees
/gt1l/sea_ice_segments/geolocation/sigma_h: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/sigma_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point ellipsoid height: 1- sigma (m). Error estimates for all other photons in the group are computed with the scale defined below.
long_name: height uncertainty
source: Sea Ice ATBD
units: 1
/gt1l/sea_ice_segments/geolocation/solar_elevation: Array of 32 bit Reals [ = 0..276542]
HDF5_OBJ_FULLPATH: /gt1l/sea_ice_segments/geolocation/solar_elevation
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low precision value, with approximately TBD degree accuracy.
long_name: solar elevation
source: Sea Ice ATBD
units: degrees
/quality_assessment/qa_granule_fail_reason: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /quality_assessment/qa_granule_fail_reason
contentType: qualityInformation
description: Flag indicating granule failure reason. 0=no failure; 1=processing error; 2=Insufficient output data was generated; 3=TBD Failure; 4=TBD_Failure; 5=other failure.
flag_meanings: no_failure PROCESS_ERROR INSUFFICIENT_OUTPUT failure_3 failure_4 OTHER_FAILURE
flag_values: 0, 1, 2, 3, 4, 5
long_name: Granule Failure Reason
source: Operations
units: 1
valid_max: 5
valid_min: 0
/quality_assessment/qa_granule_pass_fail: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /quality_assessment/qa_granule_pass_fail
contentType: qualityInformation
description: Flag indicating granule quality. 0=granule passes automatic QA. 1=granule fails automatic QA.
flag_meanings: PASS FAIL
flag_values: 0, 1
long_name: Granule Pass Flag
source: Operations
units: 1
valid_max: 1
valid_min: 0
/gt3l/sea_ice_segments/heights/height_segment_fit_quality_flag: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_fit_quality_flag
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Flag describing the quality of the results of the along-track fit. (-1=height value is invalid; 1=ngrid_w < wlength/2; 2=ngrid_w >= wlength/2; 3=ngrid_dt < dtlength/2; 4=ngrid_dt >= dtlength/2; 5=ngrid_dt >= (dtlength-2): where 1 is best and 5 is poor). Heights are reported even if this flag indicates the height is invalid.
flag_meanings: invalid best high med low poor
flag_values: -1, 1, 2, 3, 4, 5
long_name: height Quality Flag
source: ATBD, section 4.2.4.2
units: 1
valid_max: 5
valid_min: -1
/gt3l/sea_ice_segments/heights/height_segment_length_seg: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_length_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: along-track length of segment containing n_photons_actual
long_name: length of segment
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/heights/height_segment_asr_calc: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_asr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Computed apparent surface reflectance for the sea ice segment.
long_name: Calculated Apparent Surface Reflectivity
source: Sea Ice ATBD
units: 1
/gt3l/sea_ice_segments/heights/height_segment_quality: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_quality
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Height segment quality flag, 1 is good quality, 0 is bad depending on fit, wguassian, or layer flag
flag_meanings: bad_quality good_quality
flag_values: 0, 1
long_name: Height Segment Quality Flag
source: ATBD, section 4.2.4
units: 1
valid_max: 1
valid_min: 0
/gt3l/sea_ice_segments/heights/height_segment_n_pulse_seg: Array of 32 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_n_pulse_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: number of laser pulses
long_name: number of laser pulses
source: ATBD, section 4.2.2.4
units: 1
/gt3l/sea_ice_segments/heights/across_track_distance: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/across_track_distance
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Across track distance of photons averaged over the sea ice height segment.
long_name: Across Track Distance
source: ATBD, section 4.2.4
units: meters
/gt3l/sea_ice_segments/heights/height_segment_htcorr_skew: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_htcorr_skew
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: height corection for skew
long_name: Height Correction for Skew
source: ATBD, section 4.2.6
units: meters
/gt3l/sea_ice_segments/heights/height_segment_ssh_flag: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_ssh_flag
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Identifies the height segments that are candidates for use as sea surface reference in freeboard calculations in ATL10. 0 = sea ice; 1 = sea surface
flag_meanings: sea_ice sea_surface
flag_values: 0, 1
long_name: Sea Surface Flag
source: ATBD, section 4.3
units: 1
valid_max: 1
valid_min: 0
/gt3l/sea_ice_segments/heights/height_segment_height: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_height
coordinates: ../delta_time ../latitude ../longitude
description: Mean height from along-track segment fit detremined by the sea ice algorithm
long_name: height of segment surface
source: ATBD, section 4.2.2.4
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt3l/sea_ice_segments/heights/height_segment_type: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_type
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Value that indicates segment surface type as sea ice or different types of sea surface. 0=cloud covered: rsurf
flag_meanings: cloud_covered other specular_lead_low_w_bkg specular_lead_low specular_lead_high_w_bkg specular_lead_high dark_lead_smooth_w_bkg dark_lead_smooth dark_lead_rough_w_bkg dark_lead_rough
flag_values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
long_name: Segment surface type
source: ATBD, section 4.3
units: 1
valid_max: 9
valid_min: 0
/gt3l/sea_ice_segments/heights/height_segment_confidence: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_confidence
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Confidence level in the surface height estimate based on the number of photons; the background noise rate; and the error analysis
long_name: Surface height confidence
source: ATBD, section 4.2.4.2
units: 1
/gt3l/sea_ice_segments/heights/height_segment_surface_error_est: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_surface_error_est
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Error estimate of the surface height
long_name: h surface error est
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/heights/height_segment_w_gaussian: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_w_gaussian
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: width of best fit gaussian
long_name: width of best fit gaussian
source: ATBD, section 4.2.4
units: meters
/gt3l/sea_ice_segments/heights/height_segment_rms: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/heights/height_segment_rms
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: RMS difference between sea ice modeled and observed photon height distribution
long_name: height rms
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/height_segment_id: Array of 32 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/height_segment_id
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Identifier of each height segment
long_name: Identifier of each height segment
source: ATBD, section 5.2
units: 1
/gt3l/sea_ice_segments/seg_dist_x: Array of 64 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/seg_dist_x
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Along-track distance from the equator crossing to the segment center.
long_name: Along track distance
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/longitude: Array of 64 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/longitude
contentType: referenceInformation
coordinates: delta_time latitude
description: Longitude, WGS84, East=+,Lon of segment center
long_name: Longitude
source: ATBD, section 4.4
standard_name: longitude
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt3l/sea_ice_segments/latitude: Array of 64 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/latitude
contentType: referenceInformation
coordinates: delta_time longitude
description: Latitude, WGS84, North=+, Lat of segment center
long_name: Latitude
source: ATBD, section 4.4
standard_name: latitude
units: degrees_north
valid_max: 90.
valid_min: -90.
/gt3l/sea_ice_segments/geophysical/height_segment_t2m: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_t2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Temperature at 2m above the displacement height (K)
long_name: temperature_at_2m
source: ATL09
standard_name: temperature
units: K
/gt3l/sea_ice_segments/geophysical/height_segment_dac: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_dac
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect.
long_name: Dynamic Atmosphere Correction
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_ps: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_ps
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Sea Level Pressure (Pa)
long_name: sea level pressure
source: ATL09
standard_name: pressure
units: Pa
/gt3l/sea_ice_segments/geophysical/height_segment_ib: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_ib
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Inverted barometer effect calculated from surface pressure
long_name: Inverted barometer effect
source: ATBD, section 4.2
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_load: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_load
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
long_name: Load Tide
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_geoid: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_geoid
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Geoid height above WGS-84 reference ellipsoid (range -107 to 86m), based on the EGM2008 model.
long_name: EGM2008 Geoid
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_ocean: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_ocean
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium)
long_name: Ocean Tide
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_v2m: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_v2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Northward wind at 2m above the displacement height (m/s-1)
long_name: Northward_wind_at_2m
source: ATL09
standard_name: northward_wind
units: m s-1
/gt3l/sea_ice_segments/geophysical/height_segment_mss: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_mss
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean sea surface height above WGS-84 reference ellipsoid (range: -105 to 87m), based on the DTU13 model.
long_name: DTU13 Mean Sea Surface
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_u2m: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_u2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Eastward wind at 2m above the displacement height (m/s-1)
long_name: Eastward_wind_at_2m
source: ATL09
standard_name: eastward_wind
units: m s-1
/gt3l/sea_ice_segments/geophysical/height_segment_lpe: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_lpe
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). (dependent only on time and latitude)
long_name: Equilibrium Tide
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_earth: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_earth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Solid Earth Tide
long_name: Earth Tide
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geophysical/height_segment_pole: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geophysical/height_segment_pole
coordinates: ../delta_time ../latitude ../longitude
description: Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
long_name: Pole Tide
source: Sea Ice ATBD
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt3l/sea_ice_segments/geoseg_beg: Array of 32 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geoseg_beg
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the first photon used in this sea ice segment
long_name: Beginning GEOSEG
source: Sea Ice ATBD
units: 1
/gt3l/sea_ice_segments/delta_time: Array of 64 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/delta_time
contentType: physicalMeasurement
coordinates: latitude longitude
description: 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.
long_name: Elapsed GPS seconds
source: telemetry
standard_name: time
units: seconds since 2018-01-01
CLASS: DIMENSION_SCALE
NAME: gt3l/sea_ice_segments/delta_time
/gt3l/sea_ice_segments/stats/msw_flag: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/msw_flag
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Multiple Scattering warning flag. The multiple scattering warning flag (ATL09 parameter msw_flag) has values from -1 to 5 where zero means no multiple scattering and 5 the greatest. If no layers were detected, then msw_flag = 0. If blowing snow is detected and its estimated optical depth is greater than or equal to 0.5, then msw_flag = 5. If the blowing snow optical depth is less than 0.5, then msw_flag = 4. If no blowing snow is detected but there are cloud or aerosol layers detected, the msw_flag assumes values of 1 to 3 based on the height of the bottom of the lowest layer: < 1 km, msw_flag = 3; 1-3 km, msw_flag = 2; > 3km, msw_flag = 1. A value of -1 indicates that the signal to noise of the data was too low to reliably ascertain the presence of cloud or blowing snow. We expect values of -1 to occur only during daylight.
flag_meanings: cannot_determine no_layers layer_gt_3km layer_between_1_and_3_km layer_lt_1km blow_snow_od_lt_0.5 blow_snow_od_gt_0.5
flag_values: -1, 0, 1, 2, 3, 4, 5
long_name: Multiple Scattering Warning Flag
source: Atmosphere ATBD
units: 1
valid_max: 5
valid_min: -1
/gt3l/sea_ice_segments/stats/hist_median_h: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_median_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Median of the n_fit_photons heights
long_name: trimmed photon heights median
source: ATBD, section 4.2.3.1
units: meters
/gt3l/sea_ice_segments/stats/height_filter_min: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/height_filter_min
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height minimum used in the ssh height filter
long_name: Height Filter Min
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3l/sea_ice_segments/stats/cloud_flag_atm: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/cloud_flag_atm
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Number of layers found from the backscatter profile using the DDA layer finder.
long_name: Cloud Flag Atm
source: Atmosphere ATBD
units: 1
valid_max: 10
valid_min: 0
/gt3l/sea_ice_segments/stats/fpb_avg_dt: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/fpb_avg_dt
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction average dead time
long_name: fpb correction average deadtime
source: Sea Ice ATBD
units: ns
/gt3l/sea_ice_segments/stats/ds_si_hist_bins: Array of 32 bit Integers [ = 0..220]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/ds_si_hist_bins
CLASS: DIMENSION_SCALE
NAME: ds_si_hist_bins
contentType: auxiliaryInformation
description: Dimension scale indexing the sea ice histogram bins. The bin heights must be computed from information contained within the same group as the histogram.
long_name: Sea Ice Histogram Bins Dimension Scale
source: SeaIce ATBD
units: 1
/gt3l/sea_ice_segments/stats/fpb_strength: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/fpb_strength
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction strength
long_name: fpb correction strength
source: Sea Ice ATBD
units: photons/shot
/gt3l/sea_ice_segments/stats/bsnow_con: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/bsnow_con
_FillValue: 127
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow confidence
long_name: Blowing snow confidence
source: ATL09
units: 1
/gt3l/sea_ice_segments/stats/layer_flag: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/layer_flag
contentType: qualityInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
flag_meanings: likely_clear likely_cloudy
flag_values: 0, 1
long_name: Consolidated cloud flag
source: Atmosphere ATBD
units: 1
valid_max: 1
valid_min: 0
/gt3l/sea_ice_segments/stats/hist_photon_bin_size: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_photon_bin_size
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: bin size of photon height histogram
long_name: height histogram bin size
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/backgr_calc: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/backgr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Calculated background count rate based on sun angle, surface slope, unit reflectance
long_name: background count rate calculated
source: ATBD, section 4.2.3
units: hz
/gt3l/sea_ice_segments/stats/fpb_corr: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/fpb_corr
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated first-photon bias(fpb) correction to mean segment height
long_name: first photon bias correction
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/stats/bsnow_h: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/bsnow_h
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow layer top height
long_name: Blowing snow top h
source: ATL09
units: meters
/gt3l/sea_ice_segments/stats/hist_photon_bottom: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_photon_bottom
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: lower bound of height histogram
long_name: height histogram minimum
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/background_r_norm: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/background_r_norm
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background rate normalized to a fixed solar elevation angle
long_name: Normalized background (50-shot)
source: ATBD section 4.3.1.3
units: hz
/gt3l/sea_ice_segments/stats/exmax_mean_2: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/exmax_mean_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 2
long_name: Exmax Mean 2
source: sea ice ATBD Appendix E
units: meters
/gt3l/sea_ice_segments/stats/background_int_height: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/background_int_height
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: The height of the altimetric range window after subtracting the height span of the signal photon events in the 50-shot span
long_name: Height of column used in background calculation
source: ATBD, section 7.3
units: meters
/gt3l/sea_ice_segments/stats/n_photons_actual: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/n_photons_actual
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons gathered
long_name: Number of photons found for the segment
source: ATBD, section 4.2.2.4
units: 1
/gt3l/sea_ice_segments/stats/ice_conc: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/ice_conc
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: sea ice concentration
long_name: sea ice concentration
source: ATBD, section 3.1.4
units: 1
/gt3l/sea_ice_segments/stats/exmax_stdev_2: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/exmax_stdev_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 2
long_name: Exmax Stdev 2
source: sea ice ATBD Appendix E
units: meters
/gt3l/sea_ice_segments/stats/cloud_flag_asr: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/cloud_flag_asr
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Cloud flag (probability) from apparent surface reflectance. 0=clear with high confidence; 1=clear with medium confidence; 2=clear with low confidence; 3=cloudy with low confidence; 4=cloudy with medium confidence; 5=cloudy with high confidence; 6=unknown
flag_meanings: clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence unknown
flag_values: 0, 1, 2, 3, 4, 5, 6
long_name: Cloud Flag ASR
source: Atmosphere ATBD
units: 1
valid_max: 6
valid_min: 0
/gt3l/sea_ice_segments/stats/exmax_stdev_1: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/exmax_stdev_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 1
long_name: Exmax Stdev 1
source: sea ice ATBD Appendix E
units: meters
/gt3l/sea_ice_segments/stats/fpb_corr_width: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/fpb_corr_width
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction width
long_name: fpb correction width
source: Sea Ice ATBD
units: ns
/gt3l/sea_ice_segments/stats/height_coarse_stdev: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/height_coarse_stdev
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height standard deviation of coarse tracker
long_name: Coarse Height Sdev
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3l/sea_ice_segments/stats/height_filter_05: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/height_filter_05
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height fifth percentile used in the ssh height filter
long_name: Height Filter 5th Percentile
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3l/sea_ice_segments/stats/n_photons_used: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/n_photons_used
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons in the trimmed histogram.
long_name: Number of photons used for fit
source: ATBD, section 4.2.2.4
units: 1
/gt3l/sea_ice_segments/stats/backgr_r_200: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/backgr_r_200
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on ATLAS 50 pulse counts
long_name: Background rate 200 hz
source: ATL09
units: hz
/gt3l/sea_ice_segments/stats/hist_photon_top: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_photon_top
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: upper bound of height histogram
long_name: height histogram maximum
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/hist_w: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_w
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Segment histogram width estimate
long_name: Segment histogram width estimate
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/hist_mean_h: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_mean_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean of the n_fit_photons heights
long_name: photon heights mean
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/height_coarse_mn: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/height_coarse_mn
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height mean of coarse tracker
long_name: Coarse Track Height Mean
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3l/sea_ice_segments/stats/exmax_mean_1: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/exmax_mean_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 1
long_name: Exmax Mean 1
source: sea ice ATBD Appendix E
units: meters
/gt3l/sea_ice_segments/stats/hist_photon_heights: Array of 16 bit Integers [ = 0..274700][ = 0..220]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/hist_photon_heights
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Histogram of the n_fit_photons heights
long_name: photon heights histogram
source: ATBD, section 4.2.2.4
units: 1
/gt3l/sea_ice_segments/stats/trim_height_top: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/trim_height_top
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: maximum height of trimmed photons used in the surface calculation procedure
long_name: maximum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/exmax_mix: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/exmax_mix
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mix ratio
long_name: Exmax Mix
source: sea ice ATBD Appendix E
units: meters
/gt3l/sea_ice_segments/stats/asr_25: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/asr_25
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Apparent surface reflectance at 25 hz, averaged to the sea ice segment.
long_name: Apparent Surface Reflectance 25hz
source: Sea Ice ATBD
units: 1
/gt3l/sea_ice_segments/stats/photon_rate: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/photon_rate
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: photon count rate, averaged over segment
long_name: photon rate
source: ATBD, section 4.2.2.4
units: photons/shot
/gt3l/sea_ice_segments/stats/trim_height_bottom: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/trim_height_bottom
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: minimum height of trimmed photons used in the surface calculation procedure
long_name: minimum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt3l/sea_ice_segments/stats/n_photons_define: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/n_photons_define
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons to gather.
long_name: Number of photons defining the segment
source: ATBD, section 4.2.2.4
units: 1
/gt3l/sea_ice_segments/stats/backgr_r_25: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/stats/backgr_r_25
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on 25 hz atmosphere
long_name: Background rate 25hz
source: ATL09
units: hz
/gt3l/sea_ice_segments/geoseg_end: Array of 32 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geoseg_end
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the last photon used in this sea ice segment
long_name: Ending GEOSEG
source: Sea Ice ATBD
units: 1
/gt3l/sea_ice_segments/geolocation/rgt: Array of 16 bit Integers [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/rgt
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: Reference Ground track
source: Sea Ice ATBD
units: 1
valid_max: 1387
valid_min: 1
/gt3l/sea_ice_segments/geolocation/sigma_lon: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/sigma_lon
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point east longitude: 1- sigma (degrees). Applies to all other photons in the group.
long_name: longitude uncertainty
source: Sea Ice ATBD
units: degrees
/gt3l/sea_ice_segments/geolocation/ref_atm_delay: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/ref_atm_delay
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay, in range, for the reference photon.
long_name: Reference Photon Atm. Path Delay
source: Sea Ice ATBD
units: meters
/gt3l/sea_ice_segments/geolocation/beam_azimuth: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/beam_azimuth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: beam azimuth
source: Sea Ice ATBD
units: degrees_east
/gt3l/sea_ice_segments/geolocation/solar_azimuth: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/solar_azimuth
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: The direction, eastwards from north, of the sun vector as seen by an observer at the laser ground spot.
long_name: solar azimuth
source: Sea Ice ATBD
units: degrees_east
/gt3l/sea_ice_segments/geolocation/ref_atm_delay_derivative: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/ref_atm_delay_derivative
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay derivative with respect to ellipsoid for the reference photon, in meters per meter.
long_name: Derivative of Atm. Path Delay
source: Sea Ice ATBD
units: meters/meter
/gt3l/sea_ice_segments/geolocation/sigma_lat: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/sigma_lat
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point geodetic latitude: 1- sigma (degrees). Applies to all other photons in the group
long_name: latitude uncertainty
source: Sea Ice ATBD
units: 1
/gt3l/sea_ice_segments/geolocation/beam_coelev: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/beam_coelev
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot.
long_name: beam co-elevation
source: Sea Ice ATBD
units: degrees
/gt3l/sea_ice_segments/geolocation/sigma_h: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/sigma_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point ellipsoid height: 1- sigma (m). Error estimates for all other photons in the group are computed with the scale defined below.
long_name: height uncertainty
source: Sea Ice ATBD
units: 1
/gt3l/sea_ice_segments/geolocation/solar_elevation: Array of 32 bit Reals [ = 0..274700]
HDF5_OBJ_FULLPATH: /gt3l/sea_ice_segments/geolocation/solar_elevation
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low precision value, with approximately TBD degree accuracy.
long_name: solar elevation
source: Sea Ice ATBD
units: degrees
/gt2l/sea_ice_segments/heights/height_segment_fit_quality_flag: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_fit_quality_flag
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Flag describing the quality of the results of the along-track fit. (-1=height value is invalid; 1=ngrid_w < wlength/2; 2=ngrid_w >= wlength/2; 3=ngrid_dt < dtlength/2; 4=ngrid_dt >= dtlength/2; 5=ngrid_dt >= (dtlength-2): where 1 is best and 5 is poor). Heights are reported even if this flag indicates the height is invalid.
flag_meanings: invalid best high med low poor
flag_values: -1, 1, 2, 3, 4, 5
long_name: height Quality Flag
source: ATBD, section 4.2.4.2
units: 1
valid_max: 5
valid_min: -1
/gt2l/sea_ice_segments/heights/height_segment_length_seg: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_length_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: along-track length of segment containing n_photons_actual
long_name: length of segment
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/heights/height_segment_asr_calc: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_asr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Computed apparent surface reflectance for the sea ice segment.
long_name: Calculated Apparent Surface Reflectivity
source: Sea Ice ATBD
units: 1
/gt2l/sea_ice_segments/heights/height_segment_quality: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_quality
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Height segment quality flag, 1 is good quality, 0 is bad depending on fit, wguassian, or layer flag
flag_meanings: bad_quality good_quality
flag_values: 0, 1
long_name: Height Segment Quality Flag
source: ATBD, section 4.2.4
units: 1
valid_max: 1
valid_min: 0
/gt2l/sea_ice_segments/heights/height_segment_n_pulse_seg: Array of 32 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_n_pulse_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: number of laser pulses
long_name: number of laser pulses
source: ATBD, section 4.2.2.4
units: 1
/gt2l/sea_ice_segments/heights/across_track_distance: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/across_track_distance
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Across track distance of photons averaged over the sea ice height segment.
long_name: Across Track Distance
source: ATBD, section 4.2.4
units: meters
/gt2l/sea_ice_segments/heights/height_segment_htcorr_skew: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_htcorr_skew
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: height corection for skew
long_name: Height Correction for Skew
source: ATBD, section 4.2.6
units: meters
/gt2l/sea_ice_segments/heights/height_segment_ssh_flag: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_ssh_flag
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Identifies the height segments that are candidates for use as sea surface reference in freeboard calculations in ATL10. 0 = sea ice; 1 = sea surface
flag_meanings: sea_ice sea_surface
flag_values: 0, 1
long_name: Sea Surface Flag
source: ATBD, section 4.3
units: 1
valid_max: 1
valid_min: 0
/gt2l/sea_ice_segments/heights/height_segment_height: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_height
coordinates: ../delta_time ../latitude ../longitude
description: Mean height from along-track segment fit detremined by the sea ice algorithm
long_name: height of segment surface
source: ATBD, section 4.2.2.4
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt2l/sea_ice_segments/heights/height_segment_type: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_type
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Value that indicates segment surface type as sea ice or different types of sea surface. 0=cloud covered: rsurf
flag_meanings: cloud_covered other specular_lead_low_w_bkg specular_lead_low specular_lead_high_w_bkg specular_lead_high dark_lead_smooth_w_bkg dark_lead_smooth dark_lead_rough_w_bkg dark_lead_rough
flag_values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
long_name: Segment surface type
source: ATBD, section 4.3
units: 1
valid_max: 9
valid_min: 0
/gt2l/sea_ice_segments/heights/height_segment_confidence: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_confidence
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Confidence level in the surface height estimate based on the number of photons; the background noise rate; and the error analysis
long_name: Surface height confidence
source: ATBD, section 4.2.4.2
units: 1
/gt2l/sea_ice_segments/heights/height_segment_surface_error_est: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_surface_error_est
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Error estimate of the surface height
long_name: h surface error est
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/heights/height_segment_w_gaussian: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_w_gaussian
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: width of best fit gaussian
long_name: width of best fit gaussian
source: ATBD, section 4.2.4
units: meters
/gt2l/sea_ice_segments/heights/height_segment_rms: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/heights/height_segment_rms
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: RMS difference between sea ice modeled and observed photon height distribution
long_name: height rms
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/height_segment_id: Array of 32 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/height_segment_id
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Identifier of each height segment
long_name: Identifier of each height segment
source: ATBD, section 5.2
units: 1
/gt2l/sea_ice_segments/seg_dist_x: Array of 64 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/seg_dist_x
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Along-track distance from the equator crossing to the segment center.
long_name: Along track distance
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/longitude: Array of 64 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/longitude
contentType: referenceInformation
coordinates: delta_time latitude
description: Longitude, WGS84, East=+,Lon of segment center
long_name: Longitude
source: ATBD, section 4.4
standard_name: longitude
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt2l/sea_ice_segments/latitude: Array of 64 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/latitude
contentType: referenceInformation
coordinates: delta_time longitude
description: Latitude, WGS84, North=+, Lat of segment center
long_name: Latitude
source: ATBD, section 4.4
standard_name: latitude
units: degrees_north
valid_max: 90.
valid_min: -90.
/gt2l/sea_ice_segments/geophysical/height_segment_t2m: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_t2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Temperature at 2m above the displacement height (K)
long_name: temperature_at_2m
source: ATL09
standard_name: temperature
units: K
/gt2l/sea_ice_segments/geophysical/height_segment_dac: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_dac
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect.
long_name: Dynamic Atmosphere Correction
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_ps: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_ps
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Sea Level Pressure (Pa)
long_name: sea level pressure
source: ATL09
standard_name: pressure
units: Pa
/gt2l/sea_ice_segments/geophysical/height_segment_ib: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_ib
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Inverted barometer effect calculated from surface pressure
long_name: Inverted barometer effect
source: ATBD, section 4.2
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_load: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_load
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
long_name: Load Tide
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_geoid: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_geoid
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Geoid height above WGS-84 reference ellipsoid (range -107 to 86m), based on the EGM2008 model.
long_name: EGM2008 Geoid
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_ocean: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_ocean
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium)
long_name: Ocean Tide
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_v2m: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_v2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Northward wind at 2m above the displacement height (m/s-1)
long_name: Northward_wind_at_2m
source: ATL09
standard_name: northward_wind
units: m s-1
/gt2l/sea_ice_segments/geophysical/height_segment_mss: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_mss
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean sea surface height above WGS-84 reference ellipsoid (range: -105 to 87m), based on the DTU13 model.
long_name: DTU13 Mean Sea Surface
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_u2m: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_u2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Eastward wind at 2m above the displacement height (m/s-1)
long_name: Eastward_wind_at_2m
source: ATL09
standard_name: eastward_wind
units: m s-1
/gt2l/sea_ice_segments/geophysical/height_segment_lpe: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_lpe
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). (dependent only on time and latitude)
long_name: Equilibrium Tide
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_earth: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_earth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Solid Earth Tide
long_name: Earth Tide
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geophysical/height_segment_pole: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geophysical/height_segment_pole
coordinates: ../delta_time ../latitude ../longitude
description: Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
long_name: Pole Tide
source: Sea Ice ATBD
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt2l/sea_ice_segments/geoseg_beg: Array of 32 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geoseg_beg
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the first photon used in this sea ice segment
long_name: Beginning GEOSEG
source: Sea Ice ATBD
units: 1
/gt2l/sea_ice_segments/delta_time: Array of 64 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/delta_time
contentType: physicalMeasurement
coordinates: latitude longitude
description: 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.
long_name: Elapsed GPS seconds
source: telemetry
standard_name: time
units: seconds since 2018-01-01
CLASS: DIMENSION_SCALE
NAME: gt2l/sea_ice_segments/delta_time
/gt2l/sea_ice_segments/stats/msw_flag: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/msw_flag
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Multiple Scattering warning flag. The multiple scattering warning flag (ATL09 parameter msw_flag) has values from -1 to 5 where zero means no multiple scattering and 5 the greatest. If no layers were detected, then msw_flag = 0. If blowing snow is detected and its estimated optical depth is greater than or equal to 0.5, then msw_flag = 5. If the blowing snow optical depth is less than 0.5, then msw_flag = 4. If no blowing snow is detected but there are cloud or aerosol layers detected, the msw_flag assumes values of 1 to 3 based on the height of the bottom of the lowest layer: < 1 km, msw_flag = 3; 1-3 km, msw_flag = 2; > 3km, msw_flag = 1. A value of -1 indicates that the signal to noise of the data was too low to reliably ascertain the presence of cloud or blowing snow. We expect values of -1 to occur only during daylight.
flag_meanings: cannot_determine no_layers layer_gt_3km layer_between_1_and_3_km layer_lt_1km blow_snow_od_lt_0.5 blow_snow_od_gt_0.5
flag_values: -1, 0, 1, 2, 3, 4, 5
long_name: Multiple Scattering Warning Flag
source: Atmosphere ATBD
units: 1
valid_max: 5
valid_min: -1
/gt2l/sea_ice_segments/stats/hist_median_h: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_median_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Median of the n_fit_photons heights
long_name: trimmed photon heights median
source: ATBD, section 4.2.3.1
units: meters
/gt2l/sea_ice_segments/stats/height_filter_min: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/height_filter_min
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height minimum used in the ssh height filter
long_name: Height Filter Min
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2l/sea_ice_segments/stats/cloud_flag_atm: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/cloud_flag_atm
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Number of layers found from the backscatter profile using the DDA layer finder.
long_name: Cloud Flag Atm
source: Atmosphere ATBD
units: 1
valid_max: 10
valid_min: 0
/gt2l/sea_ice_segments/stats/fpb_avg_dt: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/fpb_avg_dt
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction average dead time
long_name: fpb correction average deadtime
source: Sea Ice ATBD
units: ns
/gt2l/sea_ice_segments/stats/ds_si_hist_bins: Array of 32 bit Integers [ = 0..220]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/ds_si_hist_bins
CLASS: DIMENSION_SCALE
NAME: ds_si_hist_bins
contentType: auxiliaryInformation
description: Dimension scale indexing the sea ice histogram bins. The bin heights must be computed from information contained within the same group as the histogram.
long_name: Sea Ice Histogram Bins Dimension Scale
source: SeaIce ATBD
units: 1
/gt2l/sea_ice_segments/stats/fpb_strength: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/fpb_strength
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction strength
long_name: fpb correction strength
source: Sea Ice ATBD
units: photons/shot
/gt2l/sea_ice_segments/stats/bsnow_con: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/bsnow_con
_FillValue: 127
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow confidence
long_name: Blowing snow confidence
source: ATL09
units: 1
/gt2l/sea_ice_segments/stats/layer_flag: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/layer_flag
contentType: qualityInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
flag_meanings: likely_clear likely_cloudy
flag_values: 0, 1
long_name: Consolidated cloud flag
source: Atmosphere ATBD
units: 1
valid_max: 1
valid_min: 0
/gt2l/sea_ice_segments/stats/hist_photon_bin_size: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_photon_bin_size
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: bin size of photon height histogram
long_name: height histogram bin size
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/backgr_calc: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/backgr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Calculated background count rate based on sun angle, surface slope, unit reflectance
long_name: background count rate calculated
source: ATBD, section 4.2.3
units: hz
/gt2l/sea_ice_segments/stats/fpb_corr: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/fpb_corr
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated first-photon bias(fpb) correction to mean segment height
long_name: first photon bias correction
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/stats/bsnow_h: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/bsnow_h
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow layer top height
long_name: Blowing snow top h
source: ATL09
units: meters
/gt2l/sea_ice_segments/stats/hist_photon_bottom: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_photon_bottom
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: lower bound of height histogram
long_name: height histogram minimum
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/background_r_norm: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/background_r_norm
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background rate normalized to a fixed solar elevation angle
long_name: Normalized background (50-shot)
source: ATBD section 4.3.1.3
units: hz
/gt2l/sea_ice_segments/stats/exmax_mean_2: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/exmax_mean_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 2
long_name: Exmax Mean 2
source: sea ice ATBD Appendix E
units: meters
/gt2l/sea_ice_segments/stats/background_int_height: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/background_int_height
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: The height of the altimetric range window after subtracting the height span of the signal photon events in the 50-shot span
long_name: Height of column used in background calculation
source: ATBD, section 7.3
units: meters
/gt2l/sea_ice_segments/stats/n_photons_actual: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/n_photons_actual
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons gathered
long_name: Number of photons found for the segment
source: ATBD, section 4.2.2.4
units: 1
/gt2l/sea_ice_segments/stats/ice_conc: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/ice_conc
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: sea ice concentration
long_name: sea ice concentration
source: ATBD, section 3.1.4
units: 1
/gt2l/sea_ice_segments/stats/exmax_stdev_2: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/exmax_stdev_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 2
long_name: Exmax Stdev 2
source: sea ice ATBD Appendix E
units: meters
/gt2l/sea_ice_segments/stats/cloud_flag_asr: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/cloud_flag_asr
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Cloud flag (probability) from apparent surface reflectance. 0=clear with high confidence; 1=clear with medium confidence; 2=clear with low confidence; 3=cloudy with low confidence; 4=cloudy with medium confidence; 5=cloudy with high confidence; 6=unknown
flag_meanings: clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence unknown
flag_values: 0, 1, 2, 3, 4, 5, 6
long_name: Cloud Flag ASR
source: Atmosphere ATBD
units: 1
valid_max: 6
valid_min: 0
/gt2l/sea_ice_segments/stats/exmax_stdev_1: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/exmax_stdev_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 1
long_name: Exmax Stdev 1
source: sea ice ATBD Appendix E
units: meters
/gt2l/sea_ice_segments/stats/fpb_corr_width: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/fpb_corr_width
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction width
long_name: fpb correction width
source: Sea Ice ATBD
units: ns
/gt2l/sea_ice_segments/stats/height_coarse_stdev: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/height_coarse_stdev
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height standard deviation of coarse tracker
long_name: Coarse Height Sdev
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2l/sea_ice_segments/stats/height_filter_05: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/height_filter_05
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height fifth percentile used in the ssh height filter
long_name: Height Filter 5th Percentile
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2l/sea_ice_segments/stats/n_photons_used: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/n_photons_used
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons in the trimmed histogram.
long_name: Number of photons used for fit
source: ATBD, section 4.2.2.4
units: 1
/gt2l/sea_ice_segments/stats/backgr_r_200: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/backgr_r_200
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on ATLAS 50 pulse counts
long_name: Background rate 200 hz
source: ATL09
units: hz
/gt2l/sea_ice_segments/stats/hist_photon_top: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_photon_top
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: upper bound of height histogram
long_name: height histogram maximum
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/hist_w: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_w
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Segment histogram width estimate
long_name: Segment histogram width estimate
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/hist_mean_h: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_mean_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean of the n_fit_photons heights
long_name: photon heights mean
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/height_coarse_mn: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/height_coarse_mn
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height mean of coarse tracker
long_name: Coarse Track Height Mean
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt2l/sea_ice_segments/stats/exmax_mean_1: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/exmax_mean_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 1
long_name: Exmax Mean 1
source: sea ice ATBD Appendix E
units: meters
/gt2l/sea_ice_segments/stats/hist_photon_heights: Array of 16 bit Integers [ = 0..221424][ = 0..220]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/hist_photon_heights
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Histogram of the n_fit_photons heights
long_name: photon heights histogram
source: ATBD, section 4.2.2.4
units: 1
/gt2l/sea_ice_segments/stats/trim_height_top: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/trim_height_top
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: maximum height of trimmed photons used in the surface calculation procedure
long_name: maximum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/exmax_mix: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/exmax_mix
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mix ratio
long_name: Exmax Mix
source: sea ice ATBD Appendix E
units: meters
/gt2l/sea_ice_segments/stats/asr_25: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/asr_25
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Apparent surface reflectance at 25 hz, averaged to the sea ice segment.
long_name: Apparent Surface Reflectance 25hz
source: Sea Ice ATBD
units: 1
/gt2l/sea_ice_segments/stats/photon_rate: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/photon_rate
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: photon count rate, averaged over segment
long_name: photon rate
source: ATBD, section 4.2.2.4
units: photons/shot
/gt2l/sea_ice_segments/stats/trim_height_bottom: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/trim_height_bottom
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: minimum height of trimmed photons used in the surface calculation procedure
long_name: minimum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt2l/sea_ice_segments/stats/n_photons_define: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/n_photons_define
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons to gather.
long_name: Number of photons defining the segment
source: ATBD, section 4.2.2.4
units: 1
/gt2l/sea_ice_segments/stats/backgr_r_25: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/stats/backgr_r_25
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on 25 hz atmosphere
long_name: Background rate 25hz
source: ATL09
units: hz
/gt2l/sea_ice_segments/geoseg_end: Array of 32 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geoseg_end
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the last photon used in this sea ice segment
long_name: Ending GEOSEG
source: Sea Ice ATBD
units: 1
/gt2l/sea_ice_segments/geolocation/rgt: Array of 16 bit Integers [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/rgt
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: Reference Ground track
source: Sea Ice ATBD
units: 1
valid_max: 1387
valid_min: 1
/gt2l/sea_ice_segments/geolocation/sigma_lon: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/sigma_lon
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point east longitude: 1- sigma (degrees). Applies to all other photons in the group.
long_name: longitude uncertainty
source: Sea Ice ATBD
units: degrees
/gt2l/sea_ice_segments/geolocation/ref_atm_delay: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/ref_atm_delay
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay, in range, for the reference photon.
long_name: Reference Photon Atm. Path Delay
source: Sea Ice ATBD
units: meters
/gt2l/sea_ice_segments/geolocation/beam_azimuth: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/beam_azimuth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: beam azimuth
source: Sea Ice ATBD
units: degrees_east
/gt2l/sea_ice_segments/geolocation/solar_azimuth: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/solar_azimuth
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: The direction, eastwards from north, of the sun vector as seen by an observer at the laser ground spot.
long_name: solar azimuth
source: Sea Ice ATBD
units: degrees_east
/gt2l/sea_ice_segments/geolocation/ref_atm_delay_derivative: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/ref_atm_delay_derivative
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay derivative with respect to ellipsoid for the reference photon, in meters per meter.
long_name: Derivative of Atm. Path Delay
source: Sea Ice ATBD
units: meters/meter
/gt2l/sea_ice_segments/geolocation/sigma_lat: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/sigma_lat
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point geodetic latitude: 1- sigma (degrees). Applies to all other photons in the group
long_name: latitude uncertainty
source: Sea Ice ATBD
units: 1
/gt2l/sea_ice_segments/geolocation/beam_coelev: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/beam_coelev
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot.
long_name: beam co-elevation
source: Sea Ice ATBD
units: degrees
/gt2l/sea_ice_segments/geolocation/sigma_h: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/sigma_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point ellipsoid height: 1- sigma (m). Error estimates for all other photons in the group are computed with the scale defined below.
long_name: height uncertainty
source: Sea Ice ATBD
units: 1
/gt2l/sea_ice_segments/geolocation/solar_elevation: Array of 32 bit Reals [ = 0..221424]
HDF5_OBJ_FULLPATH: /gt2l/sea_ice_segments/geolocation/solar_elevation
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low precision value, with approximately TBD degree accuracy.
long_name: solar elevation
source: Sea Ice ATBD
units: degrees
/ancillary_data/release: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/release
contentType: auxiliaryInformation
description: Release number of the granule. The release number is incremented when the software or ancillary data used to create the granule has been changed.
long_name: Release Number
source: Operations
units: 1
/ancillary_data/end_geoseg: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_geoseg
contentType: auxiliaryInformation
description: 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.
long_name: Ending Geolocation Segment
source: Derived
units: 1
/ancillary_data/version: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/version
contentType: auxiliaryInformation
description: 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.
long_name: Version
source: Operations
units: 1
/ancillary_data/end_region: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_region
contentType: auxiliaryInformation
description: 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.
long_name: Ending Region
source: Derived
units: 1
/ancillary_data/atlas_sdp_gps_epoch: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/atlas_sdp_gps_epoch
contentType: auxiliaryInformation
description: 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.
long_name: ATLAS Epoch Offset
source: Operations
units: seconds since 1980-01-06T00:00:00.000000Z
/ancillary_data/end_rgt: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_rgt
contentType: auxiliaryInformation
description: 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.
long_name: Ending Reference Groundtrack
source: Derived
units: 1
valid_max: 1387
valid_min: 1
/ancillary_data/end_delta_time: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_delta_time
contentType: auxiliaryInformation
description: 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.
long_name: ATLAS End Time (Actual)
source: Derived
standard_name: time
units: seconds since 2018-01-01
/ancillary_data/end_orbit: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_orbit
contentType: auxiliaryInformation
description: 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.
long_name: Ending Orbit Number
source: Derived
units: 1
/ancillary_data/start_cycle: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_cycle
contentType: auxiliaryInformation
description: 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.
long_name: Starting Cycle
source: Derived
units: 1
valid_max: 99
valid_min: 0
/ancillary_data/data_end_utc: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/data_end_utc
contentType: auxiliaryInformation
source: Derived
description: UTC (in CCSDS-A format) of the last data point within the granule.
long_name: End UTC Time of Granule (CCSDS-A, Actual)
units: 1
/ancillary_data/control: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/control
contentType: auxiliaryInformation
units: 1
description: PGE-specific control file used to generate this granule. To re-use, replace breaks (BR) with linefeeds.
long_name: Control File
source: Operations
/ancillary_data/start_gpssow: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_gpssow
contentType: auxiliaryInformation
description: GPS seconds-of-week of the first data point in the granule.
long_name: Start GPS SOW of Granule (Actual)
source: Derived
units: seconds
/ancillary_data/granule_end_utc: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/granule_end_utc
contentType: auxiliaryInformation
description: Requested end time (in UTC CCSDS-A) of this granule.
long_name: End UTC Time of Granule (CCSDS-A, Requested)
source: Derived
units: 1
/ancillary_data/fine_surface_finding/tep_used_gt1_strong: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/tep_used_gt1_strong
contentType: auxiliaryInformation
description: TEP used in table generation for strong beam of ground track 1 (1 or 3)
long_name: TEP Table PCE1_Strong
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/h_diff_limit: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/h_diff_limit
contentType: auxiliaryInformation
description: Maximum height difference between the two weighted Gaussian mean from the initial tracked height (units = meters)
long_name: Max Ht Difference
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/n_specular: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/n_specular
contentType: auxiliaryInformation
description: Specular returns limits
long_name: number photons Specular returns
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/tep_used_gt3_strong: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/tep_used_gt3_strong
contentType: auxiliaryInformation
description: TEP used in table generation for strong beam of ground track 3 (1 or 3)
long_name: TEP Table PCE3_Strong
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/n_spec_scale: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/n_spec_scale
contentType: auxiliaryInformation
description: Scalling parameter used for scaling value of N_SPECULAR for the weak beam. Specular returns for weak beam are defined as a shot having more photons than (N_SPECULAR/N_SPEC_SCALE)
long_name: Specular Scaling Value
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/ub_length_strong: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_length_strong
contentType: auxiliaryInformation
description: upper bound of segment length strong beam
long_name: upper bound segment length strong
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/ub_oc_switch_weak: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_oc_switch_weak
contentType: auxiliaryInformation
description: Upper bound of photon rate overlapping control for weak beam when overlap is turned off
long_name: Upper bound of overlapping control for weak beam
source: ATBD section 4.2.2.4
units: photons/shot
/ancillary_data/fine_surface_finding/bin_f: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/bin_f
contentType: auxiliaryInformation
description: bin size of fine histogram along track segment length
long_name: bin size of fine histogram
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/lb_oc_switch_strong: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/lb_oc_switch_strong
contentType: auxiliaryInformation
units: photons/shot
description: Lower bound of photon rate overlapping control for strong beam when overlap is turned off
long_name: Lower bound of overlapping control for strong beam
source: ATBD section 4.2.2.4
/ancillary_data/fine_surface_finding/lb_oc_switch_weak: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/lb_oc_switch_weak
contentType: auxiliaryInformation
units: photons/shot
description: Lower bound of photon rate overlapping control for weak beam when overlap is turned off
long_name: Lower bound of overlapping control for weak beam
source: ATBD section 4.2.2.4
/ancillary_data/fine_surface_finding/tep_used_gt2_strong: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/tep_used_gt2_strong
contentType: auxiliaryInformation
description: TEP used in table generation for strong beam of ground track 2 (1 or 3)
long_name: TEP Table PCE2_Strong
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/n_photon_min: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/n_photon_min
contentType: auxiliaryInformation
description: Minimum fraction of photons needed for tracking
long_name: Minimum number of photons
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/n_w: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/n_w
contentType: auxiliaryInformation
description: number of standard deviations
long_name: number of standard deviations
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/tep_used_gt3_weak: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/tep_used_gt3_weak
contentType: auxiliaryInformation
description: TEP used in table generation for weak beam of ground track 3 (1 or 3)
long_name: TEP Table PCE3_Weak
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/delta_h_tab: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/delta_h_tab
contentType: auxiliaryInformation
description: the waveform table spacing for the height (h) dimension
long_name: h table spacing
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/overlap_switch: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/overlap_switch
contentType: auxiliaryInformation
description: Use of overlapping height segments (1 = yes, 0 = no)
flag_meanings: no yes
flag_values: 0, 1
long_name: Overlap Segments
source: Sea Ice ATBD
units: 1
valid_max: 1
valid_min: 0
/ancillary_data/fine_surface_finding/lb_win_s: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/lb_win_s
contentType: auxiliaryInformation
source: Sea Ice ATBD
description: window (Ws) containing signal photons
long_name: lower bound window signal
units: meters
/ancillary_data/fine_surface_finding/tep_used_gt2_weak: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/tep_used_gt2_weak
contentType: auxiliaryInformation
description: TEP used in table generation for weak beam of ground track 2 (1 or 3)
long_name: TEP Table PCE2_Weak
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/tep_used_gt1_weak: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/tep_used_gt1_weak
contentType: auxiliaryInformation
description: TEP used in table generation for weak beam of ground track 1 (1 or 3)
long_name: TEP Table PCE1_Weak
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/n_s: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/n_s
contentType: auxiliaryInformation
description: photons in W_s
long_name: number photons in W_s
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/ub_win_s: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_win_s
contentType: auxiliaryInformation
description: window (Ws) containing signal photons
long_name: upper bound window signal
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/ub_length_weak: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_length_weak
contentType: auxiliaryInformation
description: upper bound of segment length weak beam
long_name: upper bound segment length weak
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/ub_h_tab: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_h_tab
contentType: auxiliaryInformation
description: the waveform upper bound for the height (h) dimension
long_name: upper bound of h table
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/ub_oc_switch_strong: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_oc_switch_strong
contentType: auxiliaryInformation
description: Upper bound of photon rate overlapping control for strong beam when overlap is turned off
long_name: Upper bound of overlapping control for strong beam
source: ATBD section 4.2.2.4
units: photons/shot
/ancillary_data/fine_surface_finding/ub_w_tab: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/ub_w_tab
contentType: auxiliaryInformation
description: the waveform upper bound for the width (w) dimension
long_name: upper bound of w table
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/n_photon_trim: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/n_photon_trim
contentType: auxiliaryInformation
description: Minimum number of photons for trimming leading/trailing bins
long_name: Min Photons
source: Sea Ice ATBD
units: 1
/ancillary_data/fine_surface_finding/delta_w_tab: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/delta_w_tab
contentType: auxiliaryInformation
description: the waveform table spacing for the width (w) dimension
long_name: w table spacing
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/lb_w_tab: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/lb_w_tab
contentType: auxiliaryInformation
description: lower bound of w table
long_name: lower bound of w table
source: Sea Ice ATBD
units: meters
/ancillary_data/fine_surface_finding/lb_h_tab: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/fine_surface_finding/lb_h_tab
contentType: auxiliaryInformation
description: lower bound of h table
long_name: lower bound of h table
source: Sea Ice ATBD
units: meters
/ancillary_data/end_cycle: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_cycle
contentType: auxiliaryInformation
long_name: Ending Cycle
description: 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.
source: Derived
units: 1
valid_max: 99
valid_min: 0
/ancillary_data/sea_ice/min_segs_count: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/min_segs_count
contentType: auxiliaryInformation
description: ATL07 granules with less than this number of strong beam sea ice segments will be marked as failed.
long_name: Minimum Segments Count
source: Sea Ice ATBD
units: 1
/ancillary_data/sea_ice/proc_beam_pair1: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/proc_beam_pair1
contentType: auxiliaryInformation
description: Indicates if beam pair 1 was processed.
flag_meanings: not_processed processed
flag_values: 0, 1
long_name: Processing Flag for Beam Pair 1
source: Operations
units: 1
valid_max: 1
valid_min: 0
/ancillary_data/sea_ice/proc_beam_pair3: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/proc_beam_pair3
contentType: auxiliaryInformation
description: Indicates if beam pair 3 was processed.
flag_meanings: not_processed processed
flag_values: 0, 1
long_name: Processing Flag for Beam Pair 3
source: Operations
units: 1
valid_max: 1
valid_min: 0
/ancillary_data/sea_ice/geoseg_min: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/geoseg_min
contentType: auxiliaryInformation
description: Indicates the minimum segment_id to process (if specified in control)
long_name: Minimum Segment ID
source: Operations
units: 1
/ancillary_data/sea_ice/proc_interval: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/proc_interval
contentType: auxiliaryInformation
description: The number of 20 meter segments of data processed in one chunk
long_name: Processing interval
source: Operations
units: 1
/ancillary_data/sea_ice/proc_beam_pair2: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/proc_beam_pair2
contentType: auxiliaryInformation
description: Indicates if beam pair 2 was processed.
flag_meanings: not_processed processed
flag_values: 0, 1
long_name: Processing Flag for Beam Pair 2
source: Operations
units: 1
valid_max: 1
valid_min: 0
/ancillary_data/sea_ice/geoseg_max: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/geoseg_max
contentType: auxiliaryInformation
description: Indicates the maximum segment_id to process (if specified in control). The actual maximum processed may be greater than specified.
long_name: Maximum Segment Id
source: Operations
units: 1
/ancillary_data/sea_ice/region: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/sea_ice/region
contentType: auxiliaryInformation
description: The index to the geographic region covered within this granule (0=no region boundaries enforced).
long_name: Region Index
source: Operations
units: 1
/ancillary_data/granule_start_utc: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/granule_start_utc
contentType: auxiliaryInformation
description: Requested start time (in UTC CCSDS-A) of this granule.
long_name: Start UTC Time of Granule (CCSDS-A, Requested)
source: Derived
units: 1
/ancillary_data/start_delta_time: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_delta_time
contentType: auxiliaryInformation
description: 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.
long_name: ATLAS Start Time (Actual)
source: Derived
standard_name: time
units: seconds since 2018-01-01
/ancillary_data/start_geoseg: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_geoseg
contentType: auxiliaryInformation
description: 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.
long_name: Starting Geolocation Segment
source: Derived
units: 1
/ancillary_data/start_orbit: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_orbit
contentType: auxiliaryInformation
description: 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.
long_name: Starting Orbit Number
source: Derived
units: 1
/ancillary_data/data_start_utc: Array of Strings [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/data_start_utc
contentType: auxiliaryInformation
source: Derived
description: UTC (in CCSDS-A format) of the first data point within the granule.
long_name: Start UTC Time of Granule (CCSDS-A, Actual)
units: 1
/ancillary_data/coarse_surface_finding/bin_c: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/bin_c
contentType: auxiliaryInformation
description: bin size of coarse histogram
long_name: bin size coarse histogram
source: Sea Ice ATBD
units: meters
/ancillary_data/coarse_surface_finding/coarse_ub_wins: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/coarse_ub_wins
contentType: auxiliaryInformation
description: Upper bound for signal photons when performing coarse tracking
long_name: Coarse_UpperBounds
source: Sea Ice ATBD
units: meters
/ancillary_data/coarse_surface_finding/th_pc: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/th_pc
contentType: auxiliaryInformation
description: percentage cloud cover coarse
long_name: threshold percentage cloud cover coarse
source: Sea Ice ATBD
units: 1
/ancillary_data/coarse_surface_finding/coarse_lb_wins: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/coarse_lb_wins
contentType: auxiliaryInformation
description: Lower bound for signal photons when performing coarse tracking
long_name: Coarse_LowerrBounds
source: Sea Ice ATBD
units: meters
/ancillary_data/coarse_surface_finding/l: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/l
contentType: auxiliaryInformation
description: along track segment length coarse
long_name: segment length coarse
source: Sea Ice ATBD
units: meters
/ancillary_data/coarse_surface_finding/th_d_bot: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/th_d_bot
contentType: auxiliaryInformation
source: Sea Ice ATBD
description: Bottom distance from mode coarse
long_name: Bottom threshold distance from mode coarse
units: meters
/ancillary_data/coarse_surface_finding/th_fm: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/th_fm
contentType: auxiliaryInformation
source: Sea Ice ATBD
description: fraction of histogram peak coarse
long_name: threshold fraction of peak coarse
units: 1
/ancillary_data/coarse_surface_finding/n_ph_min: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/n_ph_min
contentType: auxiliaryInformation
description: Minimum number of photons required for coarse track segment
long_name: Minimum Number of Photons
source: Sea Ice ATBD
units: 1
/ancillary_data/coarse_surface_finding/si_conc_min: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/si_conc_min
contentType: auxiliaryInformation
source: Sea Ice ATBD
description: Minimum sea ice concentration percentage value for which to process data.
long_name: Min SI Concentration Thresh
units: 1
/ancillary_data/coarse_surface_finding/th_d_top: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/th_d_top
contentType: auxiliaryInformation
description: Top distance from mode coarse
long_name: Top threshold distance from mode coarse
source: Sea Ice ATBD
units: meters
/ancillary_data/coarse_surface_finding/th_tc: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/coarse_surface_finding/th_tc
contentType: auxiliaryInformation
description: height deviations from surface or adjacent strong beam
long_name: Threshold height deviations
source: Sea Ice ATBD
units: 1
/ancillary_data/surface_classification/theta_ref: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/theta_ref
contentType: auxiliaryInformation
description: Solar elevation normalization angle for use of normalized background rate
long_name: Solar elevation normalization angle
source: ATBD section 4.3.1.4
units: degrees
/ancillary_data/surface_classification/height_pct: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/height_pct
contentType: auxiliaryInformation
description: Percentile of sorted heights
long_name: Percentile Hts
source: Sea Ice ATBD
units: percentile
/ancillary_data/surface_classification/w1: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/w1
contentType: auxiliaryInformation
description: max width (dark smooth lead)
long_name: max width (dark smooth lead)
source: Sea Ice ATBD
units: meters
/ancillary_data/surface_classification/beam_gain: Array of 32 bit Reals [ = 0..5]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/beam_gain
contentType: auxiliaryInformation
description: Relative gains for beams 1 through 6 where N is the beam number (Note: Beams 1, 3, and 5 are the strong beams)
long_name: relative beam gain for beams 1 through 6
source: Sea Ice ATBD
units: 1
/ancillary_data/surface_classification/p3: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/p3
contentType: auxiliaryInformation
description: photon rate (shadow)
long_name: pr (shadow)
source: Sea Ice ATBD
units: 1
/ancillary_data/surface_classification/b1: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/b1
contentType: auxiliaryInformation
description: max backgr (gray ice)
long_name: max backgr (gray ice)
source: Sea Ice ATBD
units: 1
/ancillary_data/surface_classification/p4: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/p4
contentType: auxiliaryInformation
description: photon rate (specular)
long_name: pr (specular)
source: Sea Ice ATBD
units: 1
/ancillary_data/surface_classification/w2: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/w2
contentType: auxiliaryInformation
description: max width (dark rough lead)
long_name: max width (dark rough lead)
source: Sea Ice ATBD
units: meters
/ancillary_data/surface_classification/theta_cntl: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/theta_cntl
contentType: auxiliaryInformation
source: Sea Ice ATBD
description: Solar elevation for controlling use of background rate
long_name: Solar elevation for use of background rate
units: 1
/ancillary_data/surface_classification/theta_nlb: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/theta_nlb
contentType: auxiliaryInformation
units: degrees
description: Solar elevation normalization lower bound for use of normalized background rate
long_name: Solar elevation normalization lower bound
source: ATBD section 4.3.1.4
/ancillary_data/surface_classification/p1: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/p1
contentType: auxiliaryInformation
description: photon rate (clouds)
long_name: pr (clouds)
source: Sea Ice ATBD
units: 1
/ancillary_data/surface_classification/p2: Array of 32 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/surface_classification/p2
contentType: auxiliaryInformation
description: photon rate (snow)
long_name: pr (snow)
source: Sea Ice ATBD
units: 1
/ancillary_data/end_gpsweek: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_gpsweek
contentType: auxiliaryInformation
description: GPS week number of the last data point in the granule.
long_name: Ending GPSWeek of Granule (Actual)
source: Derived
units: weeks from 1980-01-06
/ancillary_data/start_rgt: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_rgt
contentType: auxiliaryInformation
description: 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.
long_name: Starting Reference Groundtrack
source: Derived
units: 1
valid_max: 1387
valid_min: 1
/ancillary_data/end_gpssow: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/end_gpssow
contentType: auxiliaryInformation
description: GPS seconds-of-week of the last data point in the granule.
long_name: Ending GPS SOW of Granule (Actual)
source: Derived
units: seconds
/ancillary_data/qa_at_interval: Array of 64 bit Reals [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/qa_at_interval
contentType: auxiliaryInformation
description: Statistics time interval for along-track QA data.
long_name: QA Along-Track Interval
source: control
units: 1
/ancillary_data/start_region: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_region
contentType: auxiliaryInformation
description: 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.
long_name: Starting Region
source: Derived
units: 1
/ancillary_data/start_gpsweek: Array of 32 bit Integers [ = 0..0]
HDF5_OBJ_FULLPATH: /ancillary_data/start_gpsweek
contentType: auxiliaryInformation
description: GPS week number of the first data point in the granule.
long_name: Start GPSWeek of Granule (Actual)
source: Derived
units: weeks from 1980-01-06
/gt3r/sea_ice_segments/heights/height_segment_fit_quality_flag: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_fit_quality_flag
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Flag describing the quality of the results of the along-track fit. (-1=height value is invalid; 1=ngrid_w < wlength/2; 2=ngrid_w >= wlength/2; 3=ngrid_dt < dtlength/2; 4=ngrid_dt >= dtlength/2; 5=ngrid_dt >= (dtlength-2): where 1 is best and 5 is poor). Heights are reported even if this flag indicates the height is invalid.
flag_meanings: invalid best high med low poor
flag_values: -1, 1, 2, 3, 4, 5
long_name: height Quality Flag
source: ATBD, section 4.2.4.2
units: 1
valid_max: 5
valid_min: -1
/gt3r/sea_ice_segments/heights/height_segment_length_seg: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_length_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: along-track length of segment containing n_photons_actual
long_name: length of segment
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/heights/height_segment_asr_calc: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_asr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Computed apparent surface reflectance for the sea ice segment.
long_name: Calculated Apparent Surface Reflectivity
source: Sea Ice ATBD
units: 1
/gt3r/sea_ice_segments/heights/height_segment_quality: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_quality
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Height segment quality flag, 1 is good quality, 0 is bad depending on fit, wguassian, or layer flag
flag_meanings: bad_quality good_quality
flag_values: 0, 1
long_name: Height Segment Quality Flag
source: ATBD, section 4.2.4
units: 1
valid_max: 1
valid_min: 0
/gt3r/sea_ice_segments/heights/height_segment_n_pulse_seg: Array of 32 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_n_pulse_seg
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: number of laser pulses
long_name: number of laser pulses
source: ATBD, section 4.2.2.4
units: 1
/gt3r/sea_ice_segments/heights/across_track_distance: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/across_track_distance
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Across track distance of photons averaged over the sea ice height segment.
long_name: Across Track Distance
source: ATBD, section 4.2.4
units: meters
/gt3r/sea_ice_segments/heights/height_segment_htcorr_skew: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_htcorr_skew
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: height corection for skew
long_name: Height Correction for Skew
source: ATBD, section 4.2.6
units: meters
/gt3r/sea_ice_segments/heights/height_segment_ssh_flag: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_ssh_flag
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Identifies the height segments that are candidates for use as sea surface reference in freeboard calculations in ATL10. 0 = sea ice; 1 = sea surface
flag_meanings: sea_ice sea_surface
flag_values: 0, 1
long_name: Sea Surface Flag
source: ATBD, section 4.3
units: 1
valid_max: 1
valid_min: 0
/gt3r/sea_ice_segments/heights/height_segment_height: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_height
coordinates: ../delta_time ../latitude ../longitude
description: Mean height from along-track segment fit detremined by the sea ice algorithm
long_name: height of segment surface
source: ATBD, section 4.2.2.4
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt3r/sea_ice_segments/heights/height_segment_type: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_type
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Value that indicates segment surface type as sea ice or different types of sea surface. 0=cloud covered: rsurf
flag_meanings: cloud_covered other specular_lead_low_w_bkg specular_lead_low specular_lead_high_w_bkg specular_lead_high dark_lead_smooth_w_bkg dark_lead_smooth dark_lead_rough_w_bkg dark_lead_rough
flag_values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
long_name: Segment surface type
source: ATBD, section 4.3
units: 1
valid_max: 9
valid_min: 0
/gt3r/sea_ice_segments/heights/height_segment_confidence: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_confidence
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Confidence level in the surface height estimate based on the number of photons; the background noise rate; and the error analysis
long_name: Surface height confidence
source: ATBD, section 4.2.4.2
units: 1
/gt3r/sea_ice_segments/heights/height_segment_surface_error_est: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_surface_error_est
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Error estimate of the surface height
long_name: h surface error est
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/heights/height_segment_w_gaussian: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_w_gaussian
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: width of best fit gaussian
long_name: width of best fit gaussian
source: ATBD, section 4.2.4
units: meters
/gt3r/sea_ice_segments/heights/height_segment_rms: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/heights/height_segment_rms
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: RMS difference between sea ice modeled and observed photon height distribution
long_name: height rms
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/height_segment_id: Array of 32 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/height_segment_id
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Identifier of each height segment
long_name: Identifier of each height segment
source: ATBD, section 5.2
units: 1
/gt3r/sea_ice_segments/seg_dist_x: Array of 64 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/seg_dist_x
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Along-track distance from the equator crossing to the segment center.
long_name: Along track distance
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/longitude: Array of 64 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/longitude
contentType: referenceInformation
coordinates: delta_time latitude
description: Longitude, WGS84, East=+,Lon of segment center
long_name: Longitude
source: ATBD, section 4.4
standard_name: longitude
units: degrees_east
valid_max: 180.
valid_min: -180.
/gt3r/sea_ice_segments/latitude: Array of 64 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/latitude
contentType: referenceInformation
coordinates: delta_time longitude
description: Latitude, WGS84, North=+, Lat of segment center
long_name: Latitude
source: ATBD, section 4.4
standard_name: latitude
units: degrees_north
valid_max: 90.
valid_min: -90.
/gt3r/sea_ice_segments/geophysical/height_segment_t2m: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_t2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Temperature at 2m above the displacement height (K)
long_name: temperature_at_2m
source: ATL09
standard_name: temperature
units: K
/gt3r/sea_ice_segments/geophysical/height_segment_dac: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_dac
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect.
long_name: Dynamic Atmosphere Correction
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_ps: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_ps
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Sea Level Pressure (Pa)
long_name: sea level pressure
source: ATL09
standard_name: pressure
units: Pa
/gt3r/sea_ice_segments/geophysical/height_segment_ib: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_ib
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Inverted barometer effect calculated from surface pressure
long_name: Inverted barometer effect
source: ATBD, section 4.2
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_load: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_load
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
long_name: Load Tide
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_geoid: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_geoid
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Geoid height above WGS-84 reference ellipsoid (range -107 to 86m), based on the EGM2008 model.
long_name: EGM2008 Geoid
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_ocean: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_ocean
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium)
long_name: Ocean Tide
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_v2m: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_v2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Northward wind at 2m above the displacement height (m/s-1)
long_name: Northward_wind_at_2m
source: ATL09
standard_name: northward_wind
units: m s-1
/gt3r/sea_ice_segments/geophysical/height_segment_mss: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_mss
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean sea surface height above WGS-84 reference ellipsoid (range: -105 to 87m), based on the DTU13 model.
long_name: DTU13 Mean Sea Surface
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_u2m: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_u2m
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Eastward wind at 2m above the displacement height (m/s-1)
long_name: Eastward_wind_at_2m
source: ATL09
standard_name: eastward_wind
units: m s-1
/gt3r/sea_ice_segments/geophysical/height_segment_lpe: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_lpe
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). (dependent only on time and latitude)
long_name: Equilibrium Tide
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_earth: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_earth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Solid Earth Tide
long_name: Earth Tide
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geophysical/height_segment_pole: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geophysical/height_segment_pole
coordinates: ../delta_time ../latitude ../longitude
description: Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
long_name: Pole Tide
source: Sea Ice ATBD
units: meters
_FillValue: 3.402823466e+38
contentType: referenceInformation
/gt3r/sea_ice_segments/geoseg_beg: Array of 32 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geoseg_beg
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the first photon used in this sea ice segment
long_name: Beginning GEOSEG
source: Sea Ice ATBD
units: 1
/gt3r/sea_ice_segments/delta_time: Array of 64 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/delta_time
contentType: physicalMeasurement
coordinates: latitude longitude
description: 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.
long_name: Elapsed GPS seconds
source: telemetry
standard_name: time
units: seconds since 2018-01-01
CLASS: DIMENSION_SCALE
NAME: gt3r/sea_ice_segments/delta_time
/gt3r/sea_ice_segments/stats/msw_flag: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/msw_flag
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Multiple Scattering warning flag. The multiple scattering warning flag (ATL09 parameter msw_flag) has values from -1 to 5 where zero means no multiple scattering and 5 the greatest. If no layers were detected, then msw_flag = 0. If blowing snow is detected and its estimated optical depth is greater than or equal to 0.5, then msw_flag = 5. If the blowing snow optical depth is less than 0.5, then msw_flag = 4. If no blowing snow is detected but there are cloud or aerosol layers detected, the msw_flag assumes values of 1 to 3 based on the height of the bottom of the lowest layer: < 1 km, msw_flag = 3; 1-3 km, msw_flag = 2; > 3km, msw_flag = 1. A value of -1 indicates that the signal to noise of the data was too low to reliably ascertain the presence of cloud or blowing snow. We expect values of -1 to occur only during daylight.
flag_meanings: cannot_determine no_layers layer_gt_3km layer_between_1_and_3_km layer_lt_1km blow_snow_od_lt_0.5 blow_snow_od_gt_0.5
flag_values: -1, 0, 1, 2, 3, 4, 5
long_name: Multiple Scattering Warning Flag
source: Atmosphere ATBD
units: 1
valid_max: 5
valid_min: -1
/gt3r/sea_ice_segments/stats/hist_median_h: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_median_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Median of the n_fit_photons heights
long_name: trimmed photon heights median
source: ATBD, section 4.2.3.1
units: meters
/gt3r/sea_ice_segments/stats/height_filter_min: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/height_filter_min
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height minimum used in the ssh height filter
long_name: Height Filter Min
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3r/sea_ice_segments/stats/cloud_flag_atm: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/cloud_flag_atm
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Number of layers found from the backscatter profile using the DDA layer finder.
long_name: Cloud Flag Atm
source: Atmosphere ATBD
units: 1
valid_max: 10
valid_min: 0
/gt3r/sea_ice_segments/stats/fpb_avg_dt: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/fpb_avg_dt
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction average dead time
long_name: fpb correction average deadtime
source: Sea Ice ATBD
units: ns
/gt3r/sea_ice_segments/stats/ds_si_hist_bins: Array of 32 bit Integers [ = 0..220]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/ds_si_hist_bins
CLASS: DIMENSION_SCALE
NAME: ds_si_hist_bins
contentType: auxiliaryInformation
description: Dimension scale indexing the sea ice histogram bins. The bin heights must be computed from information contained within the same group as the histogram.
long_name: Sea Ice Histogram Bins Dimension Scale
source: SeaIce ATBD
units: 1
/gt3r/sea_ice_segments/stats/fpb_strength: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/fpb_strength
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction strength
long_name: fpb correction strength
source: Sea Ice ATBD
units: photons/shot
/gt3r/sea_ice_segments/stats/bsnow_con: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/bsnow_con
_FillValue: 127
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow confidence
long_name: Blowing snow confidence
source: ATL09
units: 1
/gt3r/sea_ice_segments/stats/layer_flag: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/layer_flag
contentType: qualityInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
flag_meanings: likely_clear likely_cloudy
flag_values: 0, 1
long_name: Consolidated cloud flag
source: Atmosphere ATBD
units: 1
valid_max: 1
valid_min: 0
/gt3r/sea_ice_segments/stats/hist_photon_bin_size: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_photon_bin_size
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: bin size of photon height histogram
long_name: height histogram bin size
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/backgr_calc: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/backgr_calc
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Calculated background count rate based on sun angle, surface slope, unit reflectance
long_name: background count rate calculated
source: ATBD, section 4.2.3
units: hz
/gt3r/sea_ice_segments/stats/fpb_corr: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/fpb_corr
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated first-photon bias(fpb) correction to mean segment height
long_name: first photon bias correction
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/stats/bsnow_h: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/bsnow_h
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Blowing snow layer top height
long_name: Blowing snow top h
source: ATL09
units: meters
/gt3r/sea_ice_segments/stats/hist_photon_bottom: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_photon_bottom
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: lower bound of height histogram
long_name: height histogram minimum
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/background_r_norm: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/background_r_norm
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background rate normalized to a fixed solar elevation angle
long_name: Normalized background (50-shot)
source: ATBD section 4.3.1.3
units: hz
/gt3r/sea_ice_segments/stats/exmax_mean_2: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/exmax_mean_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 2
long_name: Exmax Mean 2
source: sea ice ATBD Appendix E
units: meters
/gt3r/sea_ice_segments/stats/background_int_height: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/background_int_height
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: The height of the altimetric range window after subtracting the height span of the signal photon events in the 50-shot span
long_name: Height of column used in background calculation
source: ATBD, section 7.3
units: meters
/gt3r/sea_ice_segments/stats/n_photons_actual: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/n_photons_actual
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons gathered
long_name: Number of photons found for the segment
source: ATBD, section 4.2.2.4
units: 1
/gt3r/sea_ice_segments/stats/ice_conc: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/ice_conc
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: sea ice concentration
long_name: sea ice concentration
source: ATBD, section 3.1.4
units: 1
/gt3r/sea_ice_segments/stats/exmax_stdev_2: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/exmax_stdev_2
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 2
long_name: Exmax Stdev 2
source: sea ice ATBD Appendix E
units: meters
/gt3r/sea_ice_segments/stats/cloud_flag_asr: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/cloud_flag_asr
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: Cloud flag (probability) from apparent surface reflectance. 0=clear with high confidence; 1=clear with medium confidence; 2=clear with low confidence; 3=cloudy with low confidence; 4=cloudy with medium confidence; 5=cloudy with high confidence; 6=unknown
flag_meanings: clear_with_high_confidence clear_with_medium_confidence clear_with_low_confidence cloudy_with_low_confidence cloudy_with_medium_confidence cloudy_with_high_confidence unknown
flag_values: 0, 1, 2, 3, 4, 5, 6
long_name: Cloud Flag ASR
source: Atmosphere ATBD
units: 1
valid_max: 6
valid_min: 0
/gt3r/sea_ice_segments/stats/exmax_stdev_1: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/exmax_stdev_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height standard deviation 1
long_name: Exmax Stdev 1
source: sea ice ATBD Appendix E
units: meters
/gt3r/sea_ice_segments/stats/fpb_corr_width: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/fpb_corr_width
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: FPB correction width
long_name: fpb correction width
source: Sea Ice ATBD
units: ns
/gt3r/sea_ice_segments/stats/height_coarse_stdev: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/height_coarse_stdev
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height standard deviation of coarse tracker
long_name: Coarse Height Sdev
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3r/sea_ice_segments/stats/height_filter_05: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/height_filter_05
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height fifth percentile used in the ssh height filter
long_name: Height Filter 5th Percentile
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3r/sea_ice_segments/stats/n_photons_used: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/n_photons_used
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons in the trimmed histogram.
long_name: Number of photons used for fit
source: ATBD, section 4.2.2.4
units: 1
/gt3r/sea_ice_segments/stats/backgr_r_200: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/backgr_r_200
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on ATLAS 50 pulse counts
long_name: Background rate 200 hz
source: ATL09
units: hz
/gt3r/sea_ice_segments/stats/hist_photon_top: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_photon_top
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: upper bound of height histogram
long_name: height histogram maximum
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/hist_w: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_w
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Segment histogram width estimate
long_name: Segment histogram width estimate
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/hist_mean_h: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_mean_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Mean of the n_fit_photons heights
long_name: photon heights mean
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/height_coarse_mn: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/height_coarse_mn
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: height mean of coarse tracker
long_name: Coarse Track Height Mean
source: sea ice ATBD , sect 4.2.1.2
units: meters
/gt3r/sea_ice_segments/stats/exmax_mean_1: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/exmax_mean_1
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mean 1
long_name: Exmax Mean 1
source: sea ice ATBD Appendix E
units: meters
/gt3r/sea_ice_segments/stats/hist_photon_heights: Array of 16 bit Integers [ = 0..278029][ = 0..220]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/hist_photon_heights
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Histogram of the n_fit_photons heights
long_name: photon heights histogram
source: ATBD, section 4.2.2.4
units: 1
/gt3r/sea_ice_segments/stats/trim_height_top: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/trim_height_top
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: maximum height of trimmed photons used in the surface calculation procedure
long_name: maximum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/exmax_mix: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/exmax_mix
_FillValue: 3.402823466e+38
contentType: modelResult
coordinates: ../delta_time ../latitude ../longitude
description: exmax height mix ratio
long_name: Exmax Mix
source: sea ice ATBD Appendix E
units: meters
/gt3r/sea_ice_segments/stats/asr_25: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/asr_25
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Apparent surface reflectance at 25 hz, averaged to the sea ice segment.
long_name: Apparent Surface Reflectance 25hz
source: Sea Ice ATBD
units: 1
/gt3r/sea_ice_segments/stats/photon_rate: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/photon_rate
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: photon count rate, averaged over segment
long_name: photon rate
source: ATBD, section 4.2.2.4
units: photons/shot
/gt3r/sea_ice_segments/stats/trim_height_bottom: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/trim_height_bottom
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: minimum height of trimmed photons used in the surface calculation procedure
long_name: minimum height of trimmed photons
source: ATBD, section 4.2.2.4
units: meters
/gt3r/sea_ice_segments/stats/n_photons_define: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/n_photons_define
_FillValue: -1
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Number of photons to gather.
long_name: Number of photons defining the segment
source: ATBD, section 4.2.2.4
units: 1
/gt3r/sea_ice_segments/stats/backgr_r_25: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/stats/backgr_r_25
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Background count rate, averaged over the segment based on 25 hz atmosphere
long_name: Background rate 25hz
source: ATL09
units: hz
/gt3r/sea_ice_segments/geoseg_end: Array of 32 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geoseg_end
contentType: referenceInformation
coordinates: delta_time latitude longitude
description: Geolocation segment (geoseg) ID associated with the last photon used in this sea ice segment
long_name: Ending GEOSEG
source: Sea Ice ATBD
units: 1
/gt3r/sea_ice_segments/geolocation/rgt: Array of 16 bit Integers [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/rgt
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: Reference Ground track
source: Sea Ice ATBD
units: 1
valid_max: 1387
valid_min: 1
/gt3r/sea_ice_segments/geolocation/sigma_lon: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/sigma_lon
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point east longitude: 1- sigma (degrees). Applies to all other photons in the group.
long_name: longitude uncertainty
source: Sea Ice ATBD
units: degrees
/gt3r/sea_ice_segments/geolocation/ref_atm_delay: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/ref_atm_delay
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay, in range, for the reference photon.
long_name: Reference Photon Atm. Path Delay
source: Sea Ice ATBD
units: meters
/gt3r/sea_ice_segments/geolocation/beam_azimuth: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/beam_azimuth
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: 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.
long_name: beam azimuth
source: Sea Ice ATBD
units: degrees_east
/gt3r/sea_ice_segments/geolocation/solar_azimuth: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/solar_azimuth
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: The direction, eastwards from north, of the sun vector as seen by an observer at the laser ground spot.
long_name: solar azimuth
source: Sea Ice ATBD
units: degrees_east
/gt3r/sea_ice_segments/geolocation/ref_atm_delay_derivative: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/ref_atm_delay_derivative
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Atmospheric path delay derivative with respect to ellipsoid for the reference photon, in meters per meter.
long_name: Derivative of Atm. Path Delay
source: Sea Ice ATBD
units: meters/meter
/gt3r/sea_ice_segments/geolocation/sigma_lat: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/sigma_lat
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point geodetic latitude: 1- sigma (degrees). Applies to all other photons in the group
long_name: latitude uncertainty
source: Sea Ice ATBD
units: 1
/gt3r/sea_ice_segments/geolocation/beam_coelev: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/beam_coelev
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot.
long_name: beam co-elevation
source: Sea Ice ATBD
units: degrees
/gt3r/sea_ice_segments/geolocation/sigma_h: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/sigma_h
_FillValue: 3.402823466e+38
contentType: referenceInformation
coordinates: ../delta_time ../latitude ../longitude
description: Estimated uncertainty for the reference photon bounce point ellipsoid height: 1- sigma (m). Error estimates for all other photons in the group are computed with the scale defined below.
long_name: height uncertainty
source: Sea Ice ATBD
units: 1
/gt3r/sea_ice_segments/geolocation/solar_elevation: Array of 32 bit Reals [ = 0..278029]
HDF5_OBJ_FULLPATH: /gt3r/sea_ice_segments/geolocation/solar_elevation
contentType: physicalMeansurement
coordinates: ../delta_time ../latitude ../longitude
description: Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low precision value, with approximately TBD degree accuracy.
long_name: solar elevation
source: Sea Ice ATBD
units: degrees