ds_surf_type[
ds_surf_type=
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
1
-
description:
Dimension scale indexing the surface type array. Index=1 corresponds to Land; index = 2 corresponds to Ocean; Index = 3 corresponds to SeaIce; Index=4 corresponds to LandIce; Index=5 corresponds to InlandWater
-
flag_meanings:
land ocean seaice landice inland_water
-
flag_values:
1, 2, 3, 4, 5
-
long_name:
Surface Type Dimension Scale
-
valid_max:
5
-
valid_min:
1
ds_xyz[
ds_xyz=
0
..2]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
flag_meanings:
x y z
-
description:
Dimension scale indexing the XYZ components of velocity_sc. Index=1 corresponds to X; index = 2 corresponds to Y; Index = 3 corresponds to Z;
-
flag_values:
1, 2, 3
-
long_name:
XYZ Dimension Scale
-
units:
1
-
valid_max:
3
-
valid_min:
1
/orbit_info/crossing_time[
crossing_time=
0
..0]
(Type is Float64)
-
attributes
-
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[
crossing_time=
0
..0]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
crossing_time
-
description:
Tracks the number of 91-day cycles in the mission, beginning with 01. A unique orbit number can be determined by subtracting 1 from the cycle_number, multiplying by 1387 and adding the rgt value.
-
long_name:
Cycle Number
-
source:
POD/PPD
-
units:
counts
-
valid_max:
50
-
valid_min:
0
/orbit_info/orbit_number[
crossing_time=
0
..0]
(Type is UInt16)
-
attributes
-
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[
crossing_time=
0
..0]
(Type is Int16)
-
attributes
-
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 GT2L and GT2R. 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:
counts
-
valid_max:
1387
-
valid_min:
1
/orbit_info/sc_orient[
sc_orient_time=
0
..0]
(Type is Int8)
-
attributes
-
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[
sc_orient_time=
0
..0]
(Type is Float64)
-
attributes
-
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[
crossing_time=
0
..0]
(Type is Float64)
-
attributes
-
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/bckgrd_atlas/bckgrd_int_height[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the altimetric range window. This is the height over which the 50-shot sum is generated. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Altimetric range window width
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt1r/bckgrd_atlas/tlm_height_band1[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
long_name:
Height of the telemetry band 1
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
-
description:
The height in meters of the telemetry band 1.
/gt1r/bckgrd_atlas/bckgrd_rate[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The background count rate from the 50-shot altimetric histogram after removing the number of likely signal photons based on Section 5.
-
long_name:
Background count rate based on the ATLAS 50-shot sum
-
source:
ATL03 ATBD Section 7.3
-
units:
counts / second
/gt1r/bckgrd_atlas/tlm_top_band1[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 1, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 1.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt1r/bckgrd_atlas/tlm_top_band2[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 2, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 2.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt1r/bckgrd_atlas/bckgrd_int_height_reduced[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
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:
Altimetric range window height - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt1r/bckgrd_atlas/bckgrd_hist_top[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the top of the altimetric histogram, in meters above the WGS-84 ellipsoid, with all geophysical corrections applied. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Top of the altimetric range window
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt1r/bckgrd_atlas/bckgrd_counts_reduced[
delta_time=
0
..89489]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Number of photon counts in the 50-shot sum after subtracting the number of signal photon events, defined as in ATBD Section 5, in that span.
-
long_name:
ATLAS 50-shot background count - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt1r/bckgrd_atlas/tlm_height_band2[
delta_time=
0
..89489]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The height in meters of the telemetry band 2. (if 0, second band is not present).
-
long_name:
Height of the telemetry band 2
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
/gt1r/bckgrd_atlas/delta_time[
delta_time=
0
..89489]
(Type is Float64)
-
attributes
-
description:
Elapsed GPS Seconds from the ATLAS SDP GPS Epoch, referenced to the start of the 50-shot sum. This is based on every fiftieth laser fire time, which leads to a very close alignment with major frame boundaries (+/- 1 shot). 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 at the start of ATLAS 50-shot sum
-
source:
ATL02
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/bckgrd_atlas/bckgrd_counts[
delta_time=
0
..89489]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Onboard 50 shot background (200 Hz) sum of photon events within the altimetric range window.
-
long_name:
ATLAS 50-shot background count
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt1r/geolocation/segment_ph_cnt[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Number of photons in a given along-track segment. In the case of no photons within the segment (segment_ph_cnt=0), most other parameters are filled with invalid or best-estimate values. Maintaining geolocation segments with no photons allows for the geolocation segment arrays to be directly aligned across the gtx groups.
-
long_name:
Number of photons
-
source:
Derived
-
units:
counts
/gt1r/geolocation/segment_length[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The along-track length of the along-track segment. Nominally these are 20m, but they vary from 19.8m to 20.2m.
-
long_name:
along-track segment length
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt1r/geolocation/range_bias_corr[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The range_bias estimated from geolocation analysis.
-
long_name:
range bias correction
-
source:
ATL03G ATBD, Section 3.6
-
units:
meters
/gt1r/geolocation/neutat_delay_derivative[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Change in neutral atmospheric delay per height change
-
long_name:
(Neutral Atmosphere delay)/dh
-
source:
ATL03a ATBD
-
units:
meters/meters
/gt1r/geolocation/reference_photon_lon[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Longitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Longitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt1r/geolocation/sigma_across[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated Cartesian across-track uncertainity (1-sigma) for the refrerence photon
-
long_name:
across-track geolocation uncertainty
-
source:
ATL03G ATBD
-
units:
meters
/gt1r/geolocation/sigma_lon[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic east Longitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
longitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
degrees
/gt1r/geolocation/ref_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Azimuth of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from North and positive towards East.
-
long_name:
Azimuth
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
azimuth
-
units:
radians
/gt1r/geolocation/ref_elev[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from East-North plane and positive towards Up
-
long_name:
elevation
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
elevation
-
units:
radians
/gt1r/geolocation/neutat_ht[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Reference height of the neutral atmosphere range correction
-
long_name:
Neutral atmosphere ref height
-
source:
ATL03a ATBD
-
units:
meters
/gt1r/geolocation/solar_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The azimuth of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from North and is positive towards East. ATL03g provides this value in radians; it is converted to degrees for ATL03 output.
-
long_name:
solar azimuth
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees_east
/gt1r/geolocation/surf_type[
delta_time=
0
..163492]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Flags describing which surface types this interval is associated with. 0=not type, 1=is type. Order of array is land, ocean, sea ice, land ice, inland water.
-
flag_meanings:
not_type is_type
-
flag_values:
0, 1
-
long_name:
Surface Type
-
source:
ATL03 ATBD, Section 4
-
units:
1
-
valid_max:
1
-
valid_min:
0
/gt1r/geolocation/sigma_lat[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic Latitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
latitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt1r/geolocation/tx_pulse_width_lower[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the lower threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Lower Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt1r/geolocation/sigma_along[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated cartesian along-track uncertainanty (1-sigma) for the reference photon
-
long_name:
along-track geolocation uncertainity
-
source:
ATL03G ATBD
-
units:
meters
/gt1r/geolocation/tx_pulse_skew_est[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the averages of the lower and upper threshold crossing times. This is an estimate of the transmit pulse skew.
-
long_name:
Transmit Pulse Skew Estimate
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt1r/geolocation/tx_pulse_energy[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
physicalMeasurement
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average transmit pulse energy, measured by the internal laser energy monitor, split into per-beam measurements.
-
long_name:
Transmit Pulse Energy
-
source:
ATL02 ATBD, Section 7.2
-
units:
Joules
/gt1r/geolocation/tx_pulse_width_upper[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the upper threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Upper Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt1r/geolocation/sigma_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated height uncertainty (1-sigma) for the reference photon bounce point.
-
long_name:
height uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt1r/geolocation/podppd_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
0
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Composite POD/PPD flag that indicates the quality of input geolocation products for the specific ATL03 segment. A non-zero value may indicate that geolocation solutions are degraded. The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE.
-
flag_meanings:
nominal pod_degrade ppd_degrade podppd_degrade
-
flag_values:
0, 1, 2, 3
-
long_name:
POD_PPD Flag
-
source:
ANC04, ANC05
-
units:
1
-
valid_max:
3
-
valid_min:
0
/gt1r/geolocation/velocity_sc[
delta_time=
0
..163492]
[
ds_xyz=
0
..2]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Spacecraft velocity components (east component, north component, up component) an observer on the ground would measure. While values are common to all beams, this parameter is naturally produced as part of geolocation.
-
long_name:
spacecraft velocity
-
source:
ATL03G ATBD
-
units:
meters/second
/gt1r/geolocation/full_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be fully saturated.
-
long_name:
Full Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt1r/geolocation/segment_id[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
A 7 digit number identifiying the along-track geolocation segment number. These are sequential, starting with 1 for the first segment after an ascending equatorial crossing node.
-
long_name:
along-track segment ID number.
-
source:
ATL03 ATBD, Section 3.1
-
units:
1
/gt1r/geolocation/near_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be nearly saturated.
-
long_name:
Near Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt1r/geolocation/reference_photon_lat[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Latitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Latitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt1r/geolocation/solar_elevation[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The elevation of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from the East-North plane and is positive Up. ATL03g provides this value in radians; it is converted to degress for ATL03 output.
-
long_name:
solar elevation
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees
/gt1r/geolocation/bounce_time_offset[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the transmit time and the ground bounce time of the reference photons.
-
long_name:
ground bounce time offset
-
source:
ATL03 ATBD, Section 3.3
-
units:
seconds
/gt1r/geolocation/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
reference_photon_lat, reference_photon_lon
-
description:
Transmit time of the reference photon, measured in seconds from the atlas_sdp_gps_epoch. If there is no reference photon, this time corresponds to the approximate mid-point time associated with the along-track geolocation segment edge. 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:
Delta Time
-
source:
Derived
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/geolocation/reference_photon_index[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Index of the reference photon within the set of photons grouped within in segment. To recover the position of the reference photon within the photon-rate arrays, add ref_ph_ndx to the corresponding ph_ndx_beg and subtract 1. If no reference photon was selected, this value will indicate that the reference photon defaulted to the first photon. In the case of no photons within the segment (segment_ph_cnt=0), the value should be 0.
-
long_name:
Reference Photon Index
-
source:
ATL03 ATBD, Section 3.2
-
units:
counts
/gt1r/geolocation/altitude_sc[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
_FillValue:
1.7976931348623157e+308
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Height of the spacecraft above the WGS84 ellipsoid.
-
long_name:
Altitude
-
source:
ATL03g ATBD, Section 3.4
-
units:
meters
/gt1r/geolocation/segment_dist_x[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Along-track distance from the equator crossing to the start of the 20 meter geolocation segment.
-
long_name:
Segment Distance from EQC
-
source:
Derived
-
units:
meters
/gt1r/geolocation/neutat_delay_total[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Total neutral atmosphere delay correction (wet+dry).
-
long_name:
Total Neutral Atmospheric Delay
-
source:
ATL03a ATBD
-
units:
meters
/gt1r/geophys_corr/tide_oc_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
description:
Surface deformation of the Earth due to loading from the centrifugal effect of polar motion upon the oceans (-2 to 2 mm).
-
long_name:
Ocean Pole Tide
-
source:
ATL03 ATBD, Section 6.3.6
-
units:
meters
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
/gt1r/geophys_corr/dem_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
127
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Indicates source of the DEM height. Values: 0=None, 1=Arctic, 2=GMTED, 3=MSS, 4=Antarctic.
-
flag_meanings:
none arctic gmted mss antarctic
-
flag_values:
0, 1, 2, 3, 4
-
long_name:
dem source flag
-
source:
ATL03 ATBD Section 6.3
-
units:
1
-
valid_max:
4
-
valid_min:
0
/gt1r/geophys_corr/tide_ocean[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium). This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Ocean Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt1r/geophys_corr/tide_earth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Tides
-
long_name:
Earth Tide
-
source:
ATL03 ATBD, Section 6.3.3
-
units:
meters
/gt1r/geophys_corr/dac[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect. This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Dynamic Atmosphere Correction
-
source:
ATL03 ATBD, Section 6.3.2
-
units:
meters
/gt1r/geophys_corr/tide_load[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
-
long_name:
Load Tide
-
source:
ATL03 ATBD, Section 6.3.4
-
units:
meters
/gt1r/geophys_corr/dem_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Best available DEM (in priority of Arctic/Antarctic/GMTED/MSS) value at the location of the reference photon.
-
long_name:
DEM Height
-
source:
ATL03 ATBD Section 6.3
-
units:
meters
/gt1r/geophys_corr/tide_equilibrium[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). This correction is not applied to the photon heights and is provided only as a supplemental information.
-
long_name:
Long Period Equilibrium Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt1r/geophys_corr/geoid[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Geoid height above WGS-84 reference ellipsoid (range -107 to 86m). Not applied on the product; requested by higher-level products.
-
long_name:
Geoid
-
source:
ATL03 ATBD, Section 6.3.8
-
units:
meters
/gt1r/geophys_corr/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
description:
Elapsed seconds from the ATLAS SDP GPS Epoch, corresponding to the transmit time of the reference photon. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/geophys_corr/tide_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
-
long_name:
Solid Earth Pole Tide
-
source:
ATL03 ATBD, Section 6.3.5
-
units:
meters
/gt1r/signal_find_output/sea_ice/bckgrd_mean[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/sea_ice/bckgrd_sigma[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/sea_ice/t_pc_delta[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1r/signal_find_output/sea_ice/delta_time[
delta_time=
0
..62224]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/signal_find_output/sea_ice/z_pc_delta[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1r/signal_find_output/land/bckgrd_mean[
delta_time=
0
..5225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/land/bckgrd_sigma[
delta_time=
0
..5225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/land/t_pc_delta[
delta_time=
0
..5225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1r/signal_find_output/land/delta_time[
delta_time=
0
..5225]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/signal_find_output/land/z_pc_delta[
delta_time=
0
..5225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1r/signal_find_output/ocean/bckgrd_mean[
delta_time=
0
..72325]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/ocean/bckgrd_sigma[
delta_time=
0
..72325]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/ocean/t_pc_delta[
delta_time=
0
..72325]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1r/signal_find_output/ocean/delta_time[
delta_time=
0
..72325]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/signal_find_output/ocean/z_pc_delta[
delta_time=
0
..72325]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1r/signal_find_output/land_ice/bckgrd_mean[
delta_time=
0
..18587]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/land_ice/bckgrd_sigma[
delta_time=
0
..18587]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/land_ice/t_pc_delta[
delta_time=
0
..18587]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1r/signal_find_output/land_ice/delta_time[
delta_time=
0
..18587]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/signal_find_output/land_ice/z_pc_delta[
delta_time=
0
..18587]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1r/signal_find_output/inlandwater/bckgrd_mean[
delta_time=
0
..16566]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/inlandwater/bckgrd_sigma[
delta_time=
0
..16566]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1r/signal_find_output/inlandwater/t_pc_delta[
delta_time=
0
..16566]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1r/signal_find_output/inlandwater/delta_time[
delta_time=
0
..16566]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/signal_find_output/inlandwater/z_pc_delta[
delta_time=
0
..16566]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1r/heights/ph_id_count[
delta_time=
0
..4.10252E6]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The photon event counter is part of photon ID and counts from 1 for each channel until reset by laser pulse counter.
-
long_name:
photon event counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt1r/heights/lat_ph[
delta_time=
0
..4.10252E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lon_ph
-
description:
Latitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Latitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt1r/heights/dist_ph_along[
delta_time=
0
..4.10252E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Along-track distance in a segment projected to the ellipsoid of the received photon, based on the Along-Track Segment algorithm. Total along track distance can be found by adding this value to the sum of segment lengths measured from the start of the most recent reference groundtrack.
-
long_name:
Distance from equator crossing.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt1r/heights/signal_conf_ph[
delta_time=
0
..4.10252E6]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Confidence level associated with each photon event selected as signal. 0=noise. 1=added to allow for buffer but algorithm classifies as background; 2=low; 3=med; 4=high). This parameter is a 5xN array where N is the number of photons in the granule, and the 5 rows indicate signal finding for each surface type (in order: land, ocean, sea ice, land ice and inland water). Events not associated with a specific surface type have a confidence level of -1. Events evaluated as TEP returns have a confidence level of -2.
-
flag_meanings:
possible_tep not_considered noise buffer low medium high
-
flag_values:
-2, -1, 0, 1, 2, 3, 4
-
long_name:
Photon Signal Confidence
-
source:
ATL03 ATBD, Section 5, Conf
-
units:
1
-
valid_max:
4
-
valid_min:
-2
/gt1r/heights/ph_id_pulse[
delta_time=
0
..4.10252E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The laser pulse counter is part of photon ID and counts from 1 to 200 and is reset for each new major frame.
-
long_name:
laser pulse counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt1r/heights/h_ph[
delta_time=
0
..4.10252E6]
(Type is Float32)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Height of each received photon, relative to the WGS-84 ellipsoid including the geophysical corrections noted in Section 6. Please note that neither the geoid, ocean tide nor the dynamic atmosphere (DAC) corrections are applied to the ellipsoidal heights.
-
long_name:
Photon WGS84 Height
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
height
-
units:
meters
/gt1r/heights/ph_id_channel[
delta_time=
0
..4.10252E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Channel number assigned for each received photon event. This is part of the photon ID. Values range from 1 to 120 to span all channels and rise/fall edges. Values 1 to 60 are for falling edge; PCE1 (1 to 20), PCE 2 (21 to 40) and PCE3 (41 to 60). Values 61 to 120 are for rising edge; PCE1 (61 to 80), PCE 2 (81 to 100) and PC3 (101 to 120).
-
long_name:
Receive channel id
-
source:
Derived as part of Photon ID
-
units:
1
-
valid_max:
120
-
valid_min:
1
/gt1r/heights/lon_ph[
delta_time=
0
..4.10252E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lat_ph
-
description:
Longitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Longitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt1r/heights/delta_time[
delta_time=
0
..4.10252E6]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
lat_ph lon_ph
-
description:
The transmit time of a given photon, measured in seconds from the ATLAS Standard Data Product Epoch. Note that multiple received photons associated with a single transmit pulse will have the same delta_time. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1r/heights/pce_mframe_cnt[
delta_time=
0
..4.10252E6]
(Type is UInt32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The major frame counter is read from the digital flow controller in a given PCE card. The counter identifies individual major frames across diag and science packets. Used as part of the photon ID.
-
long_name:
PCE Major frame counter
-
source:
Retained from prior a_alt_science_ph packet
-
units:
counts
/gt1r/heights/dist_ph_across[
delta_time=
0
..4.10252E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Across-track distance projected to the ellipsoid of the received photon from the reference ground track. This is based on the Along-Track Segment algorithm described in Section 3.1.
-
long_name:
Distance off RGT.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt2r/bckgrd_atlas/bckgrd_int_height[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the altimetric range window. This is the height over which the 50-shot sum is generated. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Altimetric range window width
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt2r/bckgrd_atlas/tlm_height_band1[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
long_name:
Height of the telemetry band 1
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
-
description:
The height in meters of the telemetry band 1.
/gt2r/bckgrd_atlas/bckgrd_rate[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The background count rate from the 50-shot altimetric histogram after removing the number of likely signal photons based on Section 5.
-
long_name:
Background count rate based on the ATLAS 50-shot sum
-
source:
ATL03 ATBD Section 7.3
-
units:
counts / second
/gt2r/bckgrd_atlas/tlm_top_band1[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 1, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 1.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt2r/bckgrd_atlas/tlm_top_band2[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 2, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 2.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt2r/bckgrd_atlas/bckgrd_int_height_reduced[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
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:
Altimetric range window height - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt2r/bckgrd_atlas/bckgrd_hist_top[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the top of the altimetric histogram, in meters above the WGS-84 ellipsoid, with all geophysical corrections applied. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Top of the altimetric range window
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt2r/bckgrd_atlas/bckgrd_counts_reduced[
delta_time=
0
..91494]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Number of photon counts in the 50-shot sum after subtracting the number of signal photon events, defined as in ATBD Section 5, in that span.
-
long_name:
ATLAS 50-shot background count - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt2r/bckgrd_atlas/tlm_height_band2[
delta_time=
0
..91494]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The height in meters of the telemetry band 2. (if 0, second band is not present).
-
long_name:
Height of the telemetry band 2
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
/gt2r/bckgrd_atlas/delta_time[
delta_time=
0
..91494]
(Type is Float64)
-
attributes
-
description:
Elapsed GPS Seconds from the ATLAS SDP GPS Epoch, referenced to the start of the 50-shot sum. This is based on every fiftieth laser fire time, which leads to a very close alignment with major frame boundaries (+/- 1 shot). 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 at the start of ATLAS 50-shot sum
-
source:
ATL02
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/bckgrd_atlas/bckgrd_counts[
delta_time=
0
..91494]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Onboard 50 shot background (200 Hz) sum of photon events within the altimetric range window.
-
long_name:
ATLAS 50-shot background count
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt2r/geolocation/segment_ph_cnt[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Number of photons in a given along-track segment. In the case of no photons within the segment (segment_ph_cnt=0), most other parameters are filled with invalid or best-estimate values. Maintaining geolocation segments with no photons allows for the geolocation segment arrays to be directly aligned across the gtx groups.
-
long_name:
Number of photons
-
source:
Derived
-
units:
counts
/gt2r/geolocation/segment_length[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The along-track length of the along-track segment. Nominally these are 20m, but they vary from 19.8m to 20.2m.
-
long_name:
along-track segment length
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt2r/geolocation/range_bias_corr[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The range_bias estimated from geolocation analysis.
-
long_name:
range bias correction
-
source:
ATL03G ATBD, Section 3.6
-
units:
meters
/gt2r/geolocation/neutat_delay_derivative[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Change in neutral atmospheric delay per height change
-
long_name:
(Neutral Atmosphere delay)/dh
-
source:
ATL03a ATBD
-
units:
meters/meters
/gt2r/geolocation/reference_photon_lon[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Longitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Longitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt2r/geolocation/sigma_across[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated Cartesian across-track uncertainity (1-sigma) for the refrerence photon
-
long_name:
across-track geolocation uncertainty
-
source:
ATL03G ATBD
-
units:
meters
/gt2r/geolocation/sigma_lon[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic east Longitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
longitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
degrees
/gt2r/geolocation/ref_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Azimuth of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from North and positive towards East.
-
long_name:
Azimuth
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
azimuth
-
units:
radians
/gt2r/geolocation/ref_elev[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from East-North plane and positive towards Up
-
long_name:
elevation
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
elevation
-
units:
radians
/gt2r/geolocation/neutat_ht[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Reference height of the neutral atmosphere range correction
-
long_name:
Neutral atmosphere ref height
-
source:
ATL03a ATBD
-
units:
meters
/gt2r/geolocation/solar_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The azimuth of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from North and is positive towards East. ATL03g provides this value in radians; it is converted to degrees for ATL03 output.
-
long_name:
solar azimuth
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees_east
/gt2r/geolocation/surf_type[
delta_time=
0
..163492]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Flags describing which surface types this interval is associated with. 0=not type, 1=is type. Order of array is land, ocean, sea ice, land ice, inland water.
-
flag_meanings:
not_type is_type
-
flag_values:
0, 1
-
long_name:
Surface Type
-
source:
ATL03 ATBD, Section 4
-
units:
1
-
valid_max:
1
-
valid_min:
0
/gt2r/geolocation/sigma_lat[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic Latitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
latitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt2r/geolocation/tx_pulse_width_lower[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the lower threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Lower Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt2r/geolocation/sigma_along[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated cartesian along-track uncertainanty (1-sigma) for the reference photon
-
long_name:
along-track geolocation uncertainity
-
source:
ATL03G ATBD
-
units:
meters
/gt2r/geolocation/tx_pulse_skew_est[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the averages of the lower and upper threshold crossing times. This is an estimate of the transmit pulse skew.
-
long_name:
Transmit Pulse Skew Estimate
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt2r/geolocation/tx_pulse_energy[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
physicalMeasurement
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average transmit pulse energy, measured by the internal laser energy monitor, split into per-beam measurements.
-
long_name:
Transmit Pulse Energy
-
source:
ATL02 ATBD, Section 7.2
-
units:
Joules
/gt2r/geolocation/tx_pulse_width_upper[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the upper threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Upper Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt2r/geolocation/sigma_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated height uncertainty (1-sigma) for the reference photon bounce point.
-
long_name:
height uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt2r/geolocation/podppd_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
0
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Composite POD/PPD flag that indicates the quality of input geolocation products for the specific ATL03 segment. A non-zero value may indicate that geolocation solutions are degraded. The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE.
-
flag_meanings:
nominal pod_degrade ppd_degrade podppd_degrade
-
flag_values:
0, 1, 2, 3
-
long_name:
POD_PPD Flag
-
source:
ANC04, ANC05
-
units:
1
-
valid_max:
3
-
valid_min:
0
/gt2r/geolocation/velocity_sc[
delta_time=
0
..163492]
[
ds_xyz=
0
..2]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Spacecraft velocity components (east component, north component, up component) an observer on the ground would measure. While values are common to all beams, this parameter is naturally produced as part of geolocation.
-
long_name:
spacecraft velocity
-
source:
ATL03G ATBD
-
units:
meters/second
/gt2r/geolocation/full_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be fully saturated.
-
long_name:
Full Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt2r/geolocation/segment_id[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
A 7 digit number identifiying the along-track geolocation segment number. These are sequential, starting with 1 for the first segment after an ascending equatorial crossing node.
-
long_name:
along-track segment ID number.
-
source:
ATL03 ATBD, Section 3.1
-
units:
1
/gt2r/geolocation/near_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be nearly saturated.
-
long_name:
Near Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt2r/geolocation/reference_photon_lat[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Latitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Latitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt2r/geolocation/solar_elevation[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The elevation of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from the East-North plane and is positive Up. ATL03g provides this value in radians; it is converted to degress for ATL03 output.
-
long_name:
solar elevation
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees
/gt2r/geolocation/bounce_time_offset[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the transmit time and the ground bounce time of the reference photons.
-
long_name:
ground bounce time offset
-
source:
ATL03 ATBD, Section 3.3
-
units:
seconds
/gt2r/geolocation/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
reference_photon_lat, reference_photon_lon
-
description:
Transmit time of the reference photon, measured in seconds from the atlas_sdp_gps_epoch. If there is no reference photon, this time corresponds to the approximate mid-point time associated with the along-track geolocation segment edge. 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:
Delta Time
-
source:
Derived
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/geolocation/reference_photon_index[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Index of the reference photon within the set of photons grouped within in segment. To recover the position of the reference photon within the photon-rate arrays, add ref_ph_ndx to the corresponding ph_ndx_beg and subtract 1. If no reference photon was selected, this value will indicate that the reference photon defaulted to the first photon. In the case of no photons within the segment (segment_ph_cnt=0), the value should be 0.
-
long_name:
Reference Photon Index
-
source:
ATL03 ATBD, Section 3.2
-
units:
counts
/gt2r/geolocation/altitude_sc[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
_FillValue:
1.7976931348623157e+308
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Height of the spacecraft above the WGS84 ellipsoid.
-
long_name:
Altitude
-
source:
ATL03g ATBD, Section 3.4
-
units:
meters
/gt2r/geolocation/segment_dist_x[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Along-track distance from the equator crossing to the start of the 20 meter geolocation segment.
-
long_name:
Segment Distance from EQC
-
source:
Derived
-
units:
meters
/gt2r/geolocation/neutat_delay_total[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Total neutral atmosphere delay correction (wet+dry).
-
long_name:
Total Neutral Atmospheric Delay
-
source:
ATL03a ATBD
-
units:
meters
/gt2r/geophys_corr/tide_oc_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
description:
Surface deformation of the Earth due to loading from the centrifugal effect of polar motion upon the oceans (-2 to 2 mm).
-
long_name:
Ocean Pole Tide
-
source:
ATL03 ATBD, Section 6.3.6
-
units:
meters
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
/gt2r/geophys_corr/dem_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
127
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Indicates source of the DEM height. Values: 0=None, 1=Arctic, 2=GMTED, 3=MSS, 4=Antarctic.
-
flag_meanings:
none arctic gmted mss antarctic
-
flag_values:
0, 1, 2, 3, 4
-
long_name:
dem source flag
-
source:
ATL03 ATBD Section 6.3
-
units:
1
-
valid_max:
4
-
valid_min:
0
/gt2r/geophys_corr/tide_ocean[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium). This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Ocean Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt2r/geophys_corr/tide_earth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Tides
-
long_name:
Earth Tide
-
source:
ATL03 ATBD, Section 6.3.3
-
units:
meters
/gt2r/geophys_corr/dac[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect. This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Dynamic Atmosphere Correction
-
source:
ATL03 ATBD, Section 6.3.2
-
units:
meters
/gt2r/geophys_corr/tide_load[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
-
long_name:
Load Tide
-
source:
ATL03 ATBD, Section 6.3.4
-
units:
meters
/gt2r/geophys_corr/dem_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Best available DEM (in priority of Arctic/Antarctic/GMTED/MSS) value at the location of the reference photon.
-
long_name:
DEM Height
-
source:
ATL03 ATBD Section 6.3
-
units:
meters
/gt2r/geophys_corr/tide_equilibrium[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). This correction is not applied to the photon heights and is provided only as a supplemental information.
-
long_name:
Long Period Equilibrium Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt2r/geophys_corr/geoid[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Geoid height above WGS-84 reference ellipsoid (range -107 to 86m). Not applied on the product; requested by higher-level products.
-
long_name:
Geoid
-
source:
ATL03 ATBD, Section 6.3.8
-
units:
meters
/gt2r/geophys_corr/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
description:
Elapsed seconds from the ATLAS SDP GPS Epoch, corresponding to the transmit time of the reference photon. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/geophys_corr/tide_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
-
long_name:
Solid Earth Pole Tide
-
source:
ATL03 ATBD, Section 6.3.5
-
units:
meters
/gt2r/signal_find_output/ocean/bckgrd_mean[
delta_time=
0
..72580]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/ocean/bckgrd_sigma[
delta_time=
0
..72580]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/ocean/t_pc_delta[
delta_time=
0
..72580]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2r/signal_find_output/ocean/delta_time[
delta_time=
0
..72580]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/signal_find_output/ocean/z_pc_delta[
delta_time=
0
..72580]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2r/signal_find_output/sea_ice/bckgrd_mean[
delta_time=
0
..62143]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/sea_ice/bckgrd_sigma[
delta_time=
0
..62143]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/sea_ice/t_pc_delta[
delta_time=
0
..62143]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2r/signal_find_output/sea_ice/delta_time[
delta_time=
0
..62143]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/signal_find_output/sea_ice/z_pc_delta[
delta_time=
0
..62143]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2r/signal_find_output/land_ice/bckgrd_mean[
delta_time=
0
..18664]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/land_ice/bckgrd_sigma[
delta_time=
0
..18664]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/land_ice/t_pc_delta[
delta_time=
0
..18664]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2r/signal_find_output/land_ice/delta_time[
delta_time=
0
..18664]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/signal_find_output/land_ice/z_pc_delta[
delta_time=
0
..18664]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2r/signal_find_output/land/bckgrd_mean[
delta_time=
0
..5248]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/land/bckgrd_sigma[
delta_time=
0
..5248]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/land/t_pc_delta[
delta_time=
0
..5248]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2r/signal_find_output/land/delta_time[
delta_time=
0
..5248]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/signal_find_output/land/z_pc_delta[
delta_time=
0
..5248]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2r/signal_find_output/inlandwater/bckgrd_mean[
delta_time=
0
..16706]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/inlandwater/bckgrd_sigma[
delta_time=
0
..16706]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2r/signal_find_output/inlandwater/t_pc_delta[
delta_time=
0
..16706]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2r/signal_find_output/inlandwater/delta_time[
delta_time=
0
..16706]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/signal_find_output/inlandwater/z_pc_delta[
delta_time=
0
..16706]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2r/heights/ph_id_count[
delta_time=
0
..3.646223E6]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The photon event counter is part of photon ID and counts from 1 for each channel until reset by laser pulse counter.
-
long_name:
photon event counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt2r/heights/lat_ph[
delta_time=
0
..3.646223E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lon_ph
-
description:
Latitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Latitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt2r/heights/dist_ph_along[
delta_time=
0
..3.646223E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Along-track distance in a segment projected to the ellipsoid of the received photon, based on the Along-Track Segment algorithm. Total along track distance can be found by adding this value to the sum of segment lengths measured from the start of the most recent reference groundtrack.
-
long_name:
Distance from equator crossing.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt2r/heights/signal_conf_ph[
delta_time=
0
..3.646223E6]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Confidence level associated with each photon event selected as signal. 0=noise. 1=added to allow for buffer but algorithm classifies as background; 2=low; 3=med; 4=high). This parameter is a 5xN array where N is the number of photons in the granule, and the 5 rows indicate signal finding for each surface type (in order: land, ocean, sea ice, land ice and inland water). Events not associated with a specific surface type have a confidence level of -1. Events evaluated as TEP returns have a confidence level of -2.
-
flag_meanings:
possible_tep not_considered noise buffer low medium high
-
flag_values:
-2, -1, 0, 1, 2, 3, 4
-
long_name:
Photon Signal Confidence
-
source:
ATL03 ATBD, Section 5, Conf
-
units:
1
-
valid_max:
4
-
valid_min:
-2
/gt2r/heights/ph_id_pulse[
delta_time=
0
..3.646223E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The laser pulse counter is part of photon ID and counts from 1 to 200 and is reset for each new major frame.
-
long_name:
laser pulse counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt2r/heights/h_ph[
delta_time=
0
..3.646223E6]
(Type is Float32)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Height of each received photon, relative to the WGS-84 ellipsoid including the geophysical corrections noted in Section 6. Please note that neither the geoid, ocean tide nor the dynamic atmosphere (DAC) corrections are applied to the ellipsoidal heights.
-
long_name:
Photon WGS84 Height
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
height
-
units:
meters
/gt2r/heights/ph_id_channel[
delta_time=
0
..3.646223E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Channel number assigned for each received photon event. This is part of the photon ID. Values range from 1 to 120 to span all channels and rise/fall edges. Values 1 to 60 are for falling edge; PCE1 (1 to 20), PCE 2 (21 to 40) and PCE3 (41 to 60). Values 61 to 120 are for rising edge; PCE1 (61 to 80), PCE 2 (81 to 100) and PC3 (101 to 120).
-
long_name:
Receive channel id
-
source:
Derived as part of Photon ID
-
units:
1
-
valid_max:
120
-
valid_min:
1
/gt2r/heights/lon_ph[
delta_time=
0
..3.646223E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lat_ph
-
description:
Longitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Longitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt2r/heights/delta_time[
delta_time=
0
..3.646223E6]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
lat_ph lon_ph
-
description:
The transmit time of a given photon, measured in seconds from the ATLAS Standard Data Product Epoch. Note that multiple received photons associated with a single transmit pulse will have the same delta_time. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2r/heights/pce_mframe_cnt[
delta_time=
0
..3.646223E6]
(Type is UInt32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The major frame counter is read from the digital flow controller in a given PCE card. The counter identifies individual major frames across diag and science packets. Used as part of the photon ID.
-
long_name:
PCE Major frame counter
-
source:
Retained from prior a_alt_science_ph packet
-
units:
counts
/gt2r/heights/dist_ph_across[
delta_time=
0
..3.646223E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Across-track distance projected to the ellipsoid of the received photon from the reference ground track. This is based on the Along-Track Segment algorithm described in Section 3.1.
-
long_name:
Distance off RGT.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt1l/bckgrd_atlas/bckgrd_int_height[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the altimetric range window. This is the height over which the 50-shot sum is generated. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Altimetric range window width
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt1l/bckgrd_atlas/tlm_height_band1[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
long_name:
Height of the telemetry band 1
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
-
description:
The height in meters of the telemetry band 1.
/gt1l/bckgrd_atlas/bckgrd_rate[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The background count rate from the 50-shot altimetric histogram after removing the number of likely signal photons based on Section 5.
-
long_name:
Background count rate based on the ATLAS 50-shot sum
-
source:
ATL03 ATBD Section 7.3
-
units:
counts / second
/gt1l/bckgrd_atlas/tlm_top_band1[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 1, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 1.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt1l/bckgrd_atlas/tlm_top_band2[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 2, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 2.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt1l/bckgrd_atlas/bckgrd_int_height_reduced[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
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:
Altimetric range window height - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt1l/bckgrd_atlas/bckgrd_hist_top[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the top of the altimetric histogram, in meters above the WGS-84 ellipsoid, with all geophysical corrections applied. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Top of the altimetric range window
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt1l/bckgrd_atlas/bckgrd_counts_reduced[
delta_time=
0
..84273]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Number of photon counts in the 50-shot sum after subtracting the number of signal photon events, defined as in ATBD Section 5, in that span.
-
long_name:
ATLAS 50-shot background count - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt1l/bckgrd_atlas/tlm_height_band2[
delta_time=
0
..84273]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The height in meters of the telemetry band 2. (if 0, second band is not present).
-
long_name:
Height of the telemetry band 2
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
/gt1l/bckgrd_atlas/delta_time[
delta_time=
0
..84273]
(Type is Float64)
-
attributes
-
description:
Elapsed GPS Seconds from the ATLAS SDP GPS Epoch, referenced to the start of the 50-shot sum. This is based on every fiftieth laser fire time, which leads to a very close alignment with major frame boundaries (+/- 1 shot). 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 at the start of ATLAS 50-shot sum
-
source:
ATL02
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/bckgrd_atlas/bckgrd_counts[
delta_time=
0
..84273]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Onboard 50 shot background (200 Hz) sum of photon events within the altimetric range window.
-
long_name:
ATLAS 50-shot background count
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt1l/geolocation/segment_ph_cnt[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Number of photons in a given along-track segment. In the case of no photons within the segment (segment_ph_cnt=0), most other parameters are filled with invalid or best-estimate values. Maintaining geolocation segments with no photons allows for the geolocation segment arrays to be directly aligned across the gtx groups.
-
long_name:
Number of photons
-
source:
Derived
-
units:
counts
/gt1l/geolocation/segment_length[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The along-track length of the along-track segment. Nominally these are 20m, but they vary from 19.8m to 20.2m.
-
long_name:
along-track segment length
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt1l/geolocation/range_bias_corr[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The range_bias estimated from geolocation analysis.
-
long_name:
range bias correction
-
source:
ATL03G ATBD, Section 3.6
-
units:
meters
/gt1l/geolocation/neutat_delay_derivative[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Change in neutral atmospheric delay per height change
-
long_name:
(Neutral Atmosphere delay)/dh
-
source:
ATL03a ATBD
-
units:
meters/meters
/gt1l/geolocation/reference_photon_lon[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Longitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Longitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt1l/geolocation/sigma_across[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated Cartesian across-track uncertainity (1-sigma) for the refrerence photon
-
long_name:
across-track geolocation uncertainty
-
source:
ATL03G ATBD
-
units:
meters
/gt1l/geolocation/sigma_lon[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic east Longitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
longitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
degrees
/gt1l/geolocation/ref_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Azimuth of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from North and positive towards East.
-
long_name:
Azimuth
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
azimuth
-
units:
radians
/gt1l/geolocation/ref_elev[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from East-North plane and positive towards Up
-
long_name:
elevation
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
elevation
-
units:
radians
/gt1l/geolocation/neutat_ht[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Reference height of the neutral atmosphere range correction
-
long_name:
Neutral atmosphere ref height
-
source:
ATL03a ATBD
-
units:
meters
/gt1l/geolocation/solar_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The azimuth of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from North and is positive towards East. ATL03g provides this value in radians; it is converted to degrees for ATL03 output.
-
long_name:
solar azimuth
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees_east
/gt1l/geolocation/surf_type[
delta_time=
0
..163492]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Flags describing which surface types this interval is associated with. 0=not type, 1=is type. Order of array is land, ocean, sea ice, land ice, inland water.
-
flag_meanings:
not_type is_type
-
flag_values:
0, 1
-
long_name:
Surface Type
-
source:
ATL03 ATBD, Section 4
-
units:
1
-
valid_max:
1
-
valid_min:
0
/gt1l/geolocation/sigma_lat[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic Latitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
latitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt1l/geolocation/tx_pulse_width_lower[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the lower threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Lower Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt1l/geolocation/sigma_along[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated cartesian along-track uncertainanty (1-sigma) for the reference photon
-
long_name:
along-track geolocation uncertainity
-
source:
ATL03G ATBD
-
units:
meters
/gt1l/geolocation/tx_pulse_skew_est[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the averages of the lower and upper threshold crossing times. This is an estimate of the transmit pulse skew.
-
long_name:
Transmit Pulse Skew Estimate
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt1l/geolocation/tx_pulse_energy[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
physicalMeasurement
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average transmit pulse energy, measured by the internal laser energy monitor, split into per-beam measurements.
-
long_name:
Transmit Pulse Energy
-
source:
ATL02 ATBD, Section 7.2
-
units:
Joules
/gt1l/geolocation/tx_pulse_width_upper[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the upper threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Upper Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt1l/geolocation/sigma_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated height uncertainty (1-sigma) for the reference photon bounce point.
-
long_name:
height uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt1l/geolocation/podppd_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
0
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Composite POD/PPD flag that indicates the quality of input geolocation products for the specific ATL03 segment. A non-zero value may indicate that geolocation solutions are degraded. The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE.
-
flag_meanings:
nominal pod_degrade ppd_degrade podppd_degrade
-
flag_values:
0, 1, 2, 3
-
long_name:
POD_PPD Flag
-
source:
ANC04, ANC05
-
units:
1
-
valid_max:
3
-
valid_min:
0
/gt1l/geolocation/velocity_sc[
delta_time=
0
..163492]
[
ds_xyz=
0
..2]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Spacecraft velocity components (east component, north component, up component) an observer on the ground would measure. While values are common to all beams, this parameter is naturally produced as part of geolocation.
-
long_name:
spacecraft velocity
-
source:
ATL03G ATBD
-
units:
meters/second
/gt1l/geolocation/full_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be fully saturated.
-
long_name:
Full Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt1l/geolocation/segment_id[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
A 7 digit number identifiying the along-track geolocation segment number. These are sequential, starting with 1 for the first segment after an ascending equatorial crossing node.
-
long_name:
along-track segment ID number.
-
source:
ATL03 ATBD, Section 3.1
-
units:
1
/gt1l/geolocation/near_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be nearly saturated.
-
long_name:
Near Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt1l/geolocation/reference_photon_lat[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Latitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Latitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt1l/geolocation/solar_elevation[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The elevation of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from the East-North plane and is positive Up. ATL03g provides this value in radians; it is converted to degress for ATL03 output.
-
long_name:
solar elevation
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees
/gt1l/geolocation/bounce_time_offset[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the transmit time and the ground bounce time of the reference photons.
-
long_name:
ground bounce time offset
-
source:
ATL03 ATBD, Section 3.3
-
units:
seconds
/gt1l/geolocation/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
reference_photon_lat, reference_photon_lon
-
description:
Transmit time of the reference photon, measured in seconds from the atlas_sdp_gps_epoch. If there is no reference photon, this time corresponds to the approximate mid-point time associated with the along-track geolocation segment edge. 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:
Delta Time
-
source:
Derived
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/geolocation/reference_photon_index[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Index of the reference photon within the set of photons grouped within in segment. To recover the position of the reference photon within the photon-rate arrays, add ref_ph_ndx to the corresponding ph_ndx_beg and subtract 1. If no reference photon was selected, this value will indicate that the reference photon defaulted to the first photon. In the case of no photons within the segment (segment_ph_cnt=0), the value should be 0.
-
long_name:
Reference Photon Index
-
source:
ATL03 ATBD, Section 3.2
-
units:
counts
/gt1l/geolocation/altitude_sc[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
_FillValue:
1.7976931348623157e+308
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Height of the spacecraft above the WGS84 ellipsoid.
-
long_name:
Altitude
-
source:
ATL03g ATBD, Section 3.4
-
units:
meters
/gt1l/geolocation/segment_dist_x[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Along-track distance from the equator crossing to the start of the 20 meter geolocation segment.
-
long_name:
Segment Distance from EQC
-
source:
Derived
-
units:
meters
/gt1l/geolocation/neutat_delay_total[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Total neutral atmosphere delay correction (wet+dry).
-
long_name:
Total Neutral Atmospheric Delay
-
source:
ATL03a ATBD
-
units:
meters
/gt1l/geophys_corr/tide_oc_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
description:
Surface deformation of the Earth due to loading from the centrifugal effect of polar motion upon the oceans (-2 to 2 mm).
-
long_name:
Ocean Pole Tide
-
source:
ATL03 ATBD, Section 6.3.6
-
units:
meters
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
/gt1l/geophys_corr/dem_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
127
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Indicates source of the DEM height. Values: 0=None, 1=Arctic, 2=GMTED, 3=MSS, 4=Antarctic.
-
flag_meanings:
none arctic gmted mss antarctic
-
flag_values:
0, 1, 2, 3, 4
-
long_name:
dem source flag
-
source:
ATL03 ATBD Section 6.3
-
units:
1
-
valid_max:
4
-
valid_min:
0
/gt1l/geophys_corr/tide_ocean[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium). This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Ocean Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt1l/geophys_corr/tide_earth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Tides
-
long_name:
Earth Tide
-
source:
ATL03 ATBD, Section 6.3.3
-
units:
meters
/gt1l/geophys_corr/dac[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect. This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Dynamic Atmosphere Correction
-
source:
ATL03 ATBD, Section 6.3.2
-
units:
meters
/gt1l/geophys_corr/tide_load[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
-
long_name:
Load Tide
-
source:
ATL03 ATBD, Section 6.3.4
-
units:
meters
/gt1l/geophys_corr/dem_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Best available DEM (in priority of Arctic/Antarctic/GMTED/MSS) value at the location of the reference photon.
-
long_name:
DEM Height
-
source:
ATL03 ATBD Section 6.3
-
units:
meters
/gt1l/geophys_corr/tide_equilibrium[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). This correction is not applied to the photon heights and is provided only as a supplemental information.
-
long_name:
Long Period Equilibrium Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt1l/geophys_corr/geoid[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Geoid height above WGS-84 reference ellipsoid (range -107 to 86m). Not applied on the product; requested by higher-level products.
-
long_name:
Geoid
-
source:
ATL03 ATBD, Section 6.3.8
-
units:
meters
/gt1l/geophys_corr/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
description:
Elapsed seconds from the ATLAS SDP GPS Epoch, corresponding to the transmit time of the reference photon. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/geophys_corr/tide_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
-
long_name:
Solid Earth Pole Tide
-
source:
ATL03 ATBD, Section 6.3.5
-
units:
meters
/gt1l/signal_find_output/land/bckgrd_mean[
delta_time=
0
..4201]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/land/bckgrd_sigma[
delta_time=
0
..4201]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/land/t_pc_delta[
delta_time=
0
..4201]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1l/signal_find_output/land/delta_time[
delta_time=
0
..4201]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/signal_find_output/land/z_pc_delta[
delta_time=
0
..4201]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1l/signal_find_output/ocean/bckgrd_mean[
delta_time=
0
..61612]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/ocean/bckgrd_sigma[
delta_time=
0
..61612]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/ocean/t_pc_delta[
delta_time=
0
..61612]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1l/signal_find_output/ocean/delta_time[
delta_time=
0
..61612]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/signal_find_output/ocean/z_pc_delta[
delta_time=
0
..61612]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1l/signal_find_output/sea_ice/bckgrd_mean[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/sea_ice/bckgrd_sigma[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/sea_ice/t_pc_delta[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1l/signal_find_output/sea_ice/delta_time[
delta_time=
0
..62224]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/signal_find_output/sea_ice/z_pc_delta[
delta_time=
0
..62224]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1l/signal_find_output/land_ice/bckgrd_mean[
delta_time=
0
..10277]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/land_ice/bckgrd_sigma[
delta_time=
0
..10277]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/land_ice/t_pc_delta[
delta_time=
0
..10277]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1l/signal_find_output/land_ice/delta_time[
delta_time=
0
..10277]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/signal_find_output/land_ice/z_pc_delta[
delta_time=
0
..10277]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1l/signal_find_output/inlandwater/bckgrd_mean[
delta_time=
0
..4332]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/inlandwater/bckgrd_sigma[
delta_time=
0
..4332]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt1l/signal_find_output/inlandwater/t_pc_delta[
delta_time=
0
..4332]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt1l/signal_find_output/inlandwater/delta_time[
delta_time=
0
..4332]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/signal_find_output/inlandwater/z_pc_delta[
delta_time=
0
..4332]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt1l/heights/ph_id_count[
delta_time=
0
..2.92341E6]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The photon event counter is part of photon ID and counts from 1 for each channel until reset by laser pulse counter.
-
long_name:
photon event counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt1l/heights/lat_ph[
delta_time=
0
..2.92341E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lon_ph
-
description:
Latitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Latitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt1l/heights/dist_ph_along[
delta_time=
0
..2.92341E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Along-track distance in a segment projected to the ellipsoid of the received photon, based on the Along-Track Segment algorithm. Total along track distance can be found by adding this value to the sum of segment lengths measured from the start of the most recent reference groundtrack.
-
long_name:
Distance from equator crossing.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt1l/heights/signal_conf_ph[
delta_time=
0
..2.92341E6]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Confidence level associated with each photon event selected as signal. 0=noise. 1=added to allow for buffer but algorithm classifies as background; 2=low; 3=med; 4=high). This parameter is a 5xN array where N is the number of photons in the granule, and the 5 rows indicate signal finding for each surface type (in order: land, ocean, sea ice, land ice and inland water). Events not associated with a specific surface type have a confidence level of -1. Events evaluated as TEP returns have a confidence level of -2.
-
flag_meanings:
possible_tep not_considered noise buffer low medium high
-
flag_values:
-2, -1, 0, 1, 2, 3, 4
-
long_name:
Photon Signal Confidence
-
source:
ATL03 ATBD, Section 5, Conf
-
units:
1
-
valid_max:
4
-
valid_min:
-2
/gt1l/heights/ph_id_pulse[
delta_time=
0
..2.92341E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The laser pulse counter is part of photon ID and counts from 1 to 200 and is reset for each new major frame.
-
long_name:
laser pulse counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt1l/heights/h_ph[
delta_time=
0
..2.92341E6]
(Type is Float32)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Height of each received photon, relative to the WGS-84 ellipsoid including the geophysical corrections noted in Section 6. Please note that neither the geoid, ocean tide nor the dynamic atmosphere (DAC) corrections are applied to the ellipsoidal heights.
-
long_name:
Photon WGS84 Height
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
height
-
units:
meters
/gt1l/heights/ph_id_channel[
delta_time=
0
..2.92341E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Channel number assigned for each received photon event. This is part of the photon ID. Values range from 1 to 120 to span all channels and rise/fall edges. Values 1 to 60 are for falling edge; PCE1 (1 to 20), PCE 2 (21 to 40) and PCE3 (41 to 60). Values 61 to 120 are for rising edge; PCE1 (61 to 80), PCE 2 (81 to 100) and PC3 (101 to 120).
-
long_name:
Receive channel id
-
source:
Derived as part of Photon ID
-
units:
1
-
valid_max:
120
-
valid_min:
1
/gt1l/heights/lon_ph[
delta_time=
0
..2.92341E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lat_ph
-
description:
Longitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Longitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt1l/heights/delta_time[
delta_time=
0
..2.92341E6]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
lat_ph lon_ph
-
description:
The transmit time of a given photon, measured in seconds from the ATLAS Standard Data Product Epoch. Note that multiple received photons associated with a single transmit pulse will have the same delta_time. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt1l/heights/pce_mframe_cnt[
delta_time=
0
..2.92341E6]
(Type is UInt32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The major frame counter is read from the digital flow controller in a given PCE card. The counter identifies individual major frames across diag and science packets. Used as part of the photon ID.
-
long_name:
PCE Major frame counter
-
source:
Retained from prior a_alt_science_ph packet
-
units:
counts
/gt1l/heights/dist_ph_across[
delta_time=
0
..2.92341E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Across-track distance projected to the ellipsoid of the received photon from the reference ground track. This is based on the Along-Track Segment algorithm described in Section 3.1.
-
long_name:
Distance off RGT.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/quality_assessment/qa_granule_pass_fail[
0
..0]
(Type is Int32)
-
attributes
-
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
/quality_assessment/qa_granule_fail_reason[
0
..0]
(Type is Int32)
-
attributes
-
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/delta_time[
delta_time=
0
..0]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/quality_assessment/gt1r/qa_perc_signal_conf_ph_high[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of high-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_HIgh
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1r/qa_perc_signal_conf_ph_low[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of low-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Low
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1r/qa_perc_signal_conf_ph_med[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of medium-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Med
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1r/qa_perc_surf_type[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of geolocation segments for each surface type, based on the total number of geolocation segments.
-
long_name:
Percent_Surface_Type
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2r/qa_perc_signal_conf_ph_high[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of high-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_HIgh
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2r/qa_perc_signal_conf_ph_low[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of low-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Low
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2r/qa_perc_signal_conf_ph_med[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of medium-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Med
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2r/qa_perc_surf_type[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of geolocation segments for each surface type, based on the total number of geolocation segments.
-
long_name:
Percent_Surface_Type
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1l/qa_perc_signal_conf_ph_high[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of high-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_HIgh
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1l/qa_perc_signal_conf_ph_low[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of low-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Low
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1l/qa_perc_signal_conf_ph_med[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of medium-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Med
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt1l/qa_perc_surf_type[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of geolocation segments for each surface type, based on the total number of geolocation segments.
-
long_name:
Percent_Surface_Type
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3l/qa_perc_signal_conf_ph_high[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of high-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_HIgh
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3l/qa_perc_signal_conf_ph_low[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of low-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Low
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3l/qa_perc_signal_conf_ph_med[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of medium-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Med
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3l/qa_perc_surf_type[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of geolocation segments for each surface type, based on the total number of geolocation segments.
-
long_name:
Percent_Surface_Type
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2l/qa_perc_signal_conf_ph_high[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of high-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_HIgh
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2l/qa_perc_signal_conf_ph_low[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of low-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Low
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2l/qa_perc_signal_conf_ph_med[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of medium-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Med
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt2l/qa_perc_surf_type[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of geolocation segments for each surface type, based on the total number of geolocation segments.
-
long_name:
Percent_Surface_Type
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3r/qa_perc_signal_conf_ph_high[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of high-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_HIgh
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3r/qa_perc_signal_conf_ph_low[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of low-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Low
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3r/qa_perc_signal_conf_ph_med[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of medium-confidence signal photons for each surface type, based on the total number of photons for each surface type.
-
long_name:
Percent_Signal_Conf_Ph_Med
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/quality_assessment/gt3r/qa_perc_surf_type[
delta_time=
0
..0]
[
ds_surf_type=
0
..4]
(Type is Float64)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
../delta_time
-
description:
The percentage of geolocation segments for each surface type, based on the total number of geolocation segments.
-
long_name:
Percent_Surface_Type
-
source:
ATL03 ATBD, Section 8
-
units:
percent
/atlas_impulse_response/pce1_spot1/tep_histogram/reference_tep_flag[
tep_tod=
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Flag that indicates the reference TEP has been used in place of a more recent TEP realization. 0=dynamic TEP used; 1=static reference TEP used.
-
flag_meanings:
dynamic_tep_used, reference_tep_used
-
flag_values:
0, 1
-
long_name:
Reference TEP Used
-
source:
ATL03 ATBD, Section 7.2
-
units:
1
-
valid_max:
1
-
valid_min:
0
/atlas_impulse_response/pce1_spot1/tep_histogram/tep_bckgrd[
tep_tod=
0
..0]
(Type is Int32)
-
attributes
-
coordinates:
tep_tod
-
description:
The average number of counts in the TEP histogram bins, after excluding bins that likely contain the transmit pulse.
-
long_name:
TEP Background
-
source:
ATL02 ATBD, Section 7.2
-
units:
counts
/atlas_impulse_response/pce1_spot1/tep_histogram/tep_duration[
tep_tod=
0
..0]
(Type is Float64)
-
attributes
-
coordinates:
tep_tod
-
description:
The duration (or width) of data in the TEP histogram. Will generally be greater than 10 seconds.
-
long_name:
TEP Duration
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/atlas_impulse_response/pce1_spot1/tep_histogram/tep_hist_time[
tep_hist_time=
0
..1999]
(Type is Float64)
-
attributes
-
description:
The times associated with the TEP histogram bin centers, measured from the laser transmit time.
-
long_name:
TEP Histogram Time
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/atlas_impulse_response/pce1_spot1/tep_histogram/tep_hist[
tep_hist_time=
0
..1999]
(Type is Float64)
-
attributes
-
coordinates:
tep_hist_time
-
description:
The normalized number of counts in each bin of the TEP histogram.
-
long_name:
TEP Histogram
-
source:
ATL02 ATBD, Section 7.2
-
units:
counts
/atlas_impulse_response/pce1_spot1/tep_histogram/tep_tod[
tep_tod=
0
..0]
(Type is Float64)
-
attributes
-
description:
The time of day at of the start of the data within the TEP histogram, in seconds since the ATLAS SDP GPS 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:
TEP Time Of Day
-
source:
ATL02 ATBD, Section 7.2
-
standard_name:
time
-
units:
seconds since 2018-01-01
/atlas_impulse_response/pce2_spot3/tep_histogram/reference_tep_flag[
tep_tod=
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Flag that indicates the reference TEP has been used in place of a more recent TEP realization. 0=dynamic TEP used; 1=static reference TEP used.
-
flag_meanings:
dynamic_tep_used, reference_tep_used
-
flag_values:
0, 1
-
long_name:
Reference TEP Used
-
source:
ATL03 ATBD, Section 7.2
-
units:
1
-
valid_max:
1
-
valid_min:
0
/atlas_impulse_response/pce2_spot3/tep_histogram/tep_bckgrd[
tep_tod=
0
..0]
(Type is Int32)
-
attributes
-
coordinates:
tep_tod
-
description:
The average number of counts in the TEP histogram bins, after excluding bins that likely contain the transmit pulse.
-
long_name:
TEP Background
-
source:
ATL02 ATBD, Section 7.2
-
units:
counts
/atlas_impulse_response/pce2_spot3/tep_histogram/tep_duration[
tep_tod=
0
..0]
(Type is Float64)
-
attributes
-
coordinates:
tep_tod
-
description:
The duration (or width) of data in the TEP histogram. Will generally be greater than 10 seconds.
-
long_name:
TEP Duration
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/atlas_impulse_response/pce2_spot3/tep_histogram/tep_hist_time[
tep_hist_time=
0
..1999]
(Type is Float64)
-
attributes
-
description:
The times associated with the TEP histogram bin centers, measured from the laser transmit time.
-
long_name:
TEP Histogram Time
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/atlas_impulse_response/pce2_spot3/tep_histogram/tep_hist[
tep_hist_time=
0
..1999]
(Type is Float64)
-
attributes
-
coordinates:
tep_hist_time
-
description:
The normalized number of counts in each bin of the TEP histogram.
-
long_name:
TEP Histogram
-
source:
ATL02 ATBD, Section 7.2
-
units:
counts
/atlas_impulse_response/pce2_spot3/tep_histogram/tep_tod[
tep_tod=
0
..0]
(Type is Float64)
-
attributes
-
description:
The time of day at of the start of the data within the TEP histogram, in seconds since the ATLAS SDP GPS 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:
TEP Time Of Day
-
source:
ATL02 ATBD, Section 7.2
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/bckgrd_atlas/bckgrd_int_height[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the altimetric range window. This is the height over which the 50-shot sum is generated. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Altimetric range window width
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt3l/bckgrd_atlas/tlm_height_band1[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
long_name:
Height of the telemetry band 1
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
-
description:
The height in meters of the telemetry band 1.
/gt3l/bckgrd_atlas/bckgrd_rate[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The background count rate from the 50-shot altimetric histogram after removing the number of likely signal photons based on Section 5.
-
long_name:
Background count rate based on the ATLAS 50-shot sum
-
source:
ATL03 ATBD Section 7.3
-
units:
counts / second
/gt3l/bckgrd_atlas/tlm_top_band1[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 1, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 1.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt3l/bckgrd_atlas/tlm_top_band2[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 2, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 2.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt3l/bckgrd_atlas/bckgrd_int_height_reduced[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
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:
Altimetric range window height - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt3l/bckgrd_atlas/bckgrd_hist_top[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the top of the altimetric histogram, in meters above the WGS-84 ellipsoid, with all geophysical corrections applied. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Top of the altimetric range window
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt3l/bckgrd_atlas/bckgrd_counts_reduced[
delta_time=
0
..84253]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Number of photon counts in the 50-shot sum after subtracting the number of signal photon events, defined as in ATBD Section 5, in that span.
-
long_name:
ATLAS 50-shot background count - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt3l/bckgrd_atlas/tlm_height_band2[
delta_time=
0
..84253]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The height in meters of the telemetry band 2. (if 0, second band is not present).
-
long_name:
Height of the telemetry band 2
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
/gt3l/bckgrd_atlas/delta_time[
delta_time=
0
..84253]
(Type is Float64)
-
attributes
-
description:
Elapsed GPS Seconds from the ATLAS SDP GPS Epoch, referenced to the start of the 50-shot sum. This is based on every fiftieth laser fire time, which leads to a very close alignment with major frame boundaries (+/- 1 shot). 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 at the start of ATLAS 50-shot sum
-
source:
ATL02
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/bckgrd_atlas/bckgrd_counts[
delta_time=
0
..84253]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Onboard 50 shot background (200 Hz) sum of photon events within the altimetric range window.
-
long_name:
ATLAS 50-shot background count
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt3l/geolocation/segment_ph_cnt[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Number of photons in a given along-track segment. In the case of no photons within the segment (segment_ph_cnt=0), most other parameters are filled with invalid or best-estimate values. Maintaining geolocation segments with no photons allows for the geolocation segment arrays to be directly aligned across the gtx groups.
-
long_name:
Number of photons
-
source:
Derived
-
units:
counts
/gt3l/geolocation/segment_length[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The along-track length of the along-track segment. Nominally these are 20m, but they vary from 19.8m to 20.2m.
-
long_name:
along-track segment length
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt3l/geolocation/range_bias_corr[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The range_bias estimated from geolocation analysis.
-
long_name:
range bias correction
-
source:
ATL03G ATBD, Section 3.6
-
units:
meters
/gt3l/geolocation/neutat_delay_derivative[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Change in neutral atmospheric delay per height change
-
long_name:
(Neutral Atmosphere delay)/dh
-
source:
ATL03a ATBD
-
units:
meters/meters
/gt3l/geolocation/reference_photon_lon[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Longitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Longitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt3l/geolocation/sigma_across[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated Cartesian across-track uncertainity (1-sigma) for the refrerence photon
-
long_name:
across-track geolocation uncertainty
-
source:
ATL03G ATBD
-
units:
meters
/gt3l/geolocation/sigma_lon[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic east Longitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
longitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
degrees
/gt3l/geolocation/ref_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Azimuth of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from North and positive towards East.
-
long_name:
Azimuth
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
azimuth
-
units:
radians
/gt3l/geolocation/ref_elev[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from East-North plane and positive towards Up
-
long_name:
elevation
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
elevation
-
units:
radians
/gt3l/geolocation/neutat_ht[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Reference height of the neutral atmosphere range correction
-
long_name:
Neutral atmosphere ref height
-
source:
ATL03a ATBD
-
units:
meters
/gt3l/geolocation/solar_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The azimuth of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from North and is positive towards East. ATL03g provides this value in radians; it is converted to degrees for ATL03 output.
-
long_name:
solar azimuth
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees_east
/gt3l/geolocation/surf_type[
delta_time=
0
..163492]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Flags describing which surface types this interval is associated with. 0=not type, 1=is type. Order of array is land, ocean, sea ice, land ice, inland water.
-
flag_meanings:
not_type is_type
-
flag_values:
0, 1
-
long_name:
Surface Type
-
source:
ATL03 ATBD, Section 4
-
units:
1
-
valid_max:
1
-
valid_min:
0
/gt3l/geolocation/sigma_lat[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic Latitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
latitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt3l/geolocation/tx_pulse_width_lower[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the lower threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Lower Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt3l/geolocation/sigma_along[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated cartesian along-track uncertainanty (1-sigma) for the reference photon
-
long_name:
along-track geolocation uncertainity
-
source:
ATL03G ATBD
-
units:
meters
/gt3l/geolocation/tx_pulse_skew_est[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the averages of the lower and upper threshold crossing times. This is an estimate of the transmit pulse skew.
-
long_name:
Transmit Pulse Skew Estimate
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt3l/geolocation/tx_pulse_energy[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
physicalMeasurement
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average transmit pulse energy, measured by the internal laser energy monitor, split into per-beam measurements.
-
long_name:
Transmit Pulse Energy
-
source:
ATL02 ATBD, Section 7.2
-
units:
Joules
/gt3l/geolocation/tx_pulse_width_upper[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the upper threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Upper Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt3l/geolocation/sigma_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated height uncertainty (1-sigma) for the reference photon bounce point.
-
long_name:
height uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt3l/geolocation/podppd_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
0
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Composite POD/PPD flag that indicates the quality of input geolocation products for the specific ATL03 segment. A non-zero value may indicate that geolocation solutions are degraded. The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE.
-
flag_meanings:
nominal pod_degrade ppd_degrade podppd_degrade
-
flag_values:
0, 1, 2, 3
-
long_name:
POD_PPD Flag
-
source:
ANC04, ANC05
-
units:
1
-
valid_max:
3
-
valid_min:
0
/gt3l/geolocation/velocity_sc[
delta_time=
0
..163492]
[
ds_xyz=
0
..2]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Spacecraft velocity components (east component, north component, up component) an observer on the ground would measure. While values are common to all beams, this parameter is naturally produced as part of geolocation.
-
long_name:
spacecraft velocity
-
source:
ATL03G ATBD
-
units:
meters/second
/gt3l/geolocation/full_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be fully saturated.
-
long_name:
Full Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt3l/geolocation/segment_id[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
A 7 digit number identifiying the along-track geolocation segment number. These are sequential, starting with 1 for the first segment after an ascending equatorial crossing node.
-
long_name:
along-track segment ID number.
-
source:
ATL03 ATBD, Section 3.1
-
units:
1
/gt3l/geolocation/near_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be nearly saturated.
-
long_name:
Near Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt3l/geolocation/reference_photon_lat[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Latitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Latitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt3l/geolocation/solar_elevation[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The elevation of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from the East-North plane and is positive Up. ATL03g provides this value in radians; it is converted to degress for ATL03 output.
-
long_name:
solar elevation
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees
/gt3l/geolocation/bounce_time_offset[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the transmit time and the ground bounce time of the reference photons.
-
long_name:
ground bounce time offset
-
source:
ATL03 ATBD, Section 3.3
-
units:
seconds
/gt3l/geolocation/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
reference_photon_lat, reference_photon_lon
-
description:
Transmit time of the reference photon, measured in seconds from the atlas_sdp_gps_epoch. If there is no reference photon, this time corresponds to the approximate mid-point time associated with the along-track geolocation segment edge. 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:
Delta Time
-
source:
Derived
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/geolocation/reference_photon_index[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Index of the reference photon within the set of photons grouped within in segment. To recover the position of the reference photon within the photon-rate arrays, add ref_ph_ndx to the corresponding ph_ndx_beg and subtract 1. If no reference photon was selected, this value will indicate that the reference photon defaulted to the first photon. In the case of no photons within the segment (segment_ph_cnt=0), the value should be 0.
-
long_name:
Reference Photon Index
-
source:
ATL03 ATBD, Section 3.2
-
units:
counts
/gt3l/geolocation/altitude_sc[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
_FillValue:
1.7976931348623157e+308
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Height of the spacecraft above the WGS84 ellipsoid.
-
long_name:
Altitude
-
source:
ATL03g ATBD, Section 3.4
-
units:
meters
/gt3l/geolocation/segment_dist_x[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Along-track distance from the equator crossing to the start of the 20 meter geolocation segment.
-
long_name:
Segment Distance from EQC
-
source:
Derived
-
units:
meters
/gt3l/geolocation/neutat_delay_total[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Total neutral atmosphere delay correction (wet+dry).
-
long_name:
Total Neutral Atmospheric Delay
-
source:
ATL03a ATBD
-
units:
meters
/gt3l/geophys_corr/tide_oc_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
description:
Surface deformation of the Earth due to loading from the centrifugal effect of polar motion upon the oceans (-2 to 2 mm).
-
long_name:
Ocean Pole Tide
-
source:
ATL03 ATBD, Section 6.3.6
-
units:
meters
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
/gt3l/geophys_corr/dem_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
127
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Indicates source of the DEM height. Values: 0=None, 1=Arctic, 2=GMTED, 3=MSS, 4=Antarctic.
-
flag_meanings:
none arctic gmted mss antarctic
-
flag_values:
0, 1, 2, 3, 4
-
long_name:
dem source flag
-
source:
ATL03 ATBD Section 6.3
-
units:
1
-
valid_max:
4
-
valid_min:
0
/gt3l/geophys_corr/tide_ocean[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium). This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Ocean Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt3l/geophys_corr/tide_earth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Tides
-
long_name:
Earth Tide
-
source:
ATL03 ATBD, Section 6.3.3
-
units:
meters
/gt3l/geophys_corr/dac[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect. This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Dynamic Atmosphere Correction
-
source:
ATL03 ATBD, Section 6.3.2
-
units:
meters
/gt3l/geophys_corr/tide_load[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
-
long_name:
Load Tide
-
source:
ATL03 ATBD, Section 6.3.4
-
units:
meters
/gt3l/geophys_corr/dem_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Best available DEM (in priority of Arctic/Antarctic/GMTED/MSS) value at the location of the reference photon.
-
long_name:
DEM Height
-
source:
ATL03 ATBD Section 6.3
-
units:
meters
/gt3l/geophys_corr/tide_equilibrium[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). This correction is not applied to the photon heights and is provided only as a supplemental information.
-
long_name:
Long Period Equilibrium Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt3l/geophys_corr/geoid[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Geoid height above WGS-84 reference ellipsoid (range -107 to 86m). Not applied on the product; requested by higher-level products.
-
long_name:
Geoid
-
source:
ATL03 ATBD, Section 6.3.8
-
units:
meters
/gt3l/geophys_corr/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
description:
Elapsed seconds from the ATLAS SDP GPS Epoch, corresponding to the transmit time of the reference photon. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/geophys_corr/tide_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
-
long_name:
Solid Earth Pole Tide
-
source:
ATL03 ATBD, Section 6.3.5
-
units:
meters
/gt3l/signal_find_output/land/bckgrd_mean[
delta_time=
0
..4352]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/land/bckgrd_sigma[
delta_time=
0
..4352]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/land/t_pc_delta[
delta_time=
0
..4352]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3l/signal_find_output/land/delta_time[
delta_time=
0
..4352]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/signal_find_output/land/z_pc_delta[
delta_time=
0
..4352]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3l/signal_find_output/ocean/bckgrd_mean[
delta_time=
0
..61871]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/ocean/bckgrd_sigma[
delta_time=
0
..61871]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/ocean/t_pc_delta[
delta_time=
0
..61871]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3l/signal_find_output/ocean/delta_time[
delta_time=
0
..61871]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/signal_find_output/ocean/z_pc_delta[
delta_time=
0
..61871]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3l/signal_find_output/sea_ice/bckgrd_mean[
delta_time=
0
..62237]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/sea_ice/bckgrd_sigma[
delta_time=
0
..62237]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/sea_ice/t_pc_delta[
delta_time=
0
..62237]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3l/signal_find_output/sea_ice/delta_time[
delta_time=
0
..62237]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/signal_find_output/sea_ice/z_pc_delta[
delta_time=
0
..62237]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3l/signal_find_output/land_ice/bckgrd_mean[
delta_time=
0
..10627]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/land_ice/bckgrd_sigma[
delta_time=
0
..10627]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/land_ice/t_pc_delta[
delta_time=
0
..10627]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3l/signal_find_output/land_ice/delta_time[
delta_time=
0
..10627]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/signal_find_output/land_ice/z_pc_delta[
delta_time=
0
..10627]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3l/signal_find_output/inlandwater/bckgrd_mean[
delta_time=
0
..4527]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/inlandwater/bckgrd_sigma[
delta_time=
0
..4527]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3l/signal_find_output/inlandwater/t_pc_delta[
delta_time=
0
..4527]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3l/signal_find_output/inlandwater/delta_time[
delta_time=
0
..4527]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/signal_find_output/inlandwater/z_pc_delta[
delta_time=
0
..4527]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3l/heights/ph_id_count[
delta_time=
0
..2.785147E6]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The photon event counter is part of photon ID and counts from 1 for each channel until reset by laser pulse counter.
-
long_name:
photon event counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt3l/heights/lat_ph[
delta_time=
0
..2.785147E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lon_ph
-
description:
Latitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Latitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt3l/heights/dist_ph_along[
delta_time=
0
..2.785147E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Along-track distance in a segment projected to the ellipsoid of the received photon, based on the Along-Track Segment algorithm. Total along track distance can be found by adding this value to the sum of segment lengths measured from the start of the most recent reference groundtrack.
-
long_name:
Distance from equator crossing.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt3l/heights/signal_conf_ph[
delta_time=
0
..2.785147E6]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Confidence level associated with each photon event selected as signal. 0=noise. 1=added to allow for buffer but algorithm classifies as background; 2=low; 3=med; 4=high). This parameter is a 5xN array where N is the number of photons in the granule, and the 5 rows indicate signal finding for each surface type (in order: land, ocean, sea ice, land ice and inland water). Events not associated with a specific surface type have a confidence level of -1. Events evaluated as TEP returns have a confidence level of -2.
-
flag_meanings:
possible_tep not_considered noise buffer low medium high
-
flag_values:
-2, -1, 0, 1, 2, 3, 4
-
long_name:
Photon Signal Confidence
-
source:
ATL03 ATBD, Section 5, Conf
-
units:
1
-
valid_max:
4
-
valid_min:
-2
/gt3l/heights/ph_id_pulse[
delta_time=
0
..2.785147E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The laser pulse counter is part of photon ID and counts from 1 to 200 and is reset for each new major frame.
-
long_name:
laser pulse counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt3l/heights/h_ph[
delta_time=
0
..2.785147E6]
(Type is Float32)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Height of each received photon, relative to the WGS-84 ellipsoid including the geophysical corrections noted in Section 6. Please note that neither the geoid, ocean tide nor the dynamic atmosphere (DAC) corrections are applied to the ellipsoidal heights.
-
long_name:
Photon WGS84 Height
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
height
-
units:
meters
/gt3l/heights/ph_id_channel[
delta_time=
0
..2.785147E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Channel number assigned for each received photon event. This is part of the photon ID. Values range from 1 to 120 to span all channels and rise/fall edges. Values 1 to 60 are for falling edge; PCE1 (1 to 20), PCE 2 (21 to 40) and PCE3 (41 to 60). Values 61 to 120 are for rising edge; PCE1 (61 to 80), PCE 2 (81 to 100) and PC3 (101 to 120).
-
long_name:
Receive channel id
-
source:
Derived as part of Photon ID
-
units:
1
-
valid_max:
120
-
valid_min:
1
/gt3l/heights/lon_ph[
delta_time=
0
..2.785147E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lat_ph
-
description:
Longitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Longitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt3l/heights/delta_time[
delta_time=
0
..2.785147E6]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
lat_ph lon_ph
-
description:
The transmit time of a given photon, measured in seconds from the ATLAS Standard Data Product Epoch. Note that multiple received photons associated with a single transmit pulse will have the same delta_time. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3l/heights/pce_mframe_cnt[
delta_time=
0
..2.785147E6]
(Type is UInt32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The major frame counter is read from the digital flow controller in a given PCE card. The counter identifies individual major frames across diag and science packets. Used as part of the photon ID.
-
long_name:
PCE Major frame counter
-
source:
Retained from prior a_alt_science_ph packet
-
units:
counts
/gt3l/heights/dist_ph_across[
delta_time=
0
..2.785147E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Across-track distance projected to the ellipsoid of the received photon from the reference ground track. This is based on the Along-Track Segment algorithm described in Section 3.1.
-
long_name:
Distance off RGT.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt2l/bckgrd_atlas/bckgrd_int_height[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the altimetric range window. This is the height over which the 50-shot sum is generated. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Altimetric range window width
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt2l/bckgrd_atlas/tlm_height_band1[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
long_name:
Height of the telemetry band 1
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
-
description:
The height in meters of the telemetry band 1.
/gt2l/bckgrd_atlas/bckgrd_rate[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The background count rate from the 50-shot altimetric histogram after removing the number of likely signal photons based on Section 5.
-
long_name:
Background count rate based on the ATLAS 50-shot sum
-
source:
ATL03 ATBD Section 7.3
-
units:
counts / second
/gt2l/bckgrd_atlas/tlm_top_band1[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 1, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 1.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt2l/bckgrd_atlas/tlm_top_band2[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 2, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 2.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt2l/bckgrd_atlas/bckgrd_int_height_reduced[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
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:
Altimetric range window height - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt2l/bckgrd_atlas/bckgrd_hist_top[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the top of the altimetric histogram, in meters above the WGS-84 ellipsoid, with all geophysical corrections applied. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Top of the altimetric range window
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt2l/bckgrd_atlas/bckgrd_counts_reduced[
delta_time=
0
..84260]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Number of photon counts in the 50-shot sum after subtracting the number of signal photon events, defined as in ATBD Section 5, in that span.
-
long_name:
ATLAS 50-shot background count - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt2l/bckgrd_atlas/tlm_height_band2[
delta_time=
0
..84260]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The height in meters of the telemetry band 2. (if 0, second band is not present).
-
long_name:
Height of the telemetry band 2
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
/gt2l/bckgrd_atlas/delta_time[
delta_time=
0
..84260]
(Type is Float64)
-
attributes
-
description:
Elapsed GPS Seconds from the ATLAS SDP GPS Epoch, referenced to the start of the 50-shot sum. This is based on every fiftieth laser fire time, which leads to a very close alignment with major frame boundaries (+/- 1 shot). 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 at the start of ATLAS 50-shot sum
-
source:
ATL02
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/bckgrd_atlas/bckgrd_counts[
delta_time=
0
..84260]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Onboard 50 shot background (200 Hz) sum of photon events within the altimetric range window.
-
long_name:
ATLAS 50-shot background count
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt2l/geolocation/segment_ph_cnt[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Number of photons in a given along-track segment. In the case of no photons within the segment (segment_ph_cnt=0), most other parameters are filled with invalid or best-estimate values. Maintaining geolocation segments with no photons allows for the geolocation segment arrays to be directly aligned across the gtx groups.
-
long_name:
Number of photons
-
source:
Derived
-
units:
counts
/gt2l/geolocation/segment_length[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The along-track length of the along-track segment. Nominally these are 20m, but they vary from 19.8m to 20.2m.
-
long_name:
along-track segment length
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt2l/geolocation/range_bias_corr[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The range_bias estimated from geolocation analysis.
-
long_name:
range bias correction
-
source:
ATL03G ATBD, Section 3.6
-
units:
meters
/gt2l/geolocation/neutat_delay_derivative[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Change in neutral atmospheric delay per height change
-
long_name:
(Neutral Atmosphere delay)/dh
-
source:
ATL03a ATBD
-
units:
meters/meters
/gt2l/geolocation/reference_photon_lon[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Longitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Longitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt2l/geolocation/sigma_across[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated Cartesian across-track uncertainity (1-sigma) for the refrerence photon
-
long_name:
across-track geolocation uncertainty
-
source:
ATL03G ATBD
-
units:
meters
/gt2l/geolocation/sigma_lon[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic east Longitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
longitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
degrees
/gt2l/geolocation/ref_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Azimuth of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from North and positive towards East.
-
long_name:
Azimuth
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
azimuth
-
units:
radians
/gt2l/geolocation/ref_elev[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from East-North plane and positive towards Up
-
long_name:
elevation
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
elevation
-
units:
radians
/gt2l/geolocation/neutat_ht[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Reference height of the neutral atmosphere range correction
-
long_name:
Neutral atmosphere ref height
-
source:
ATL03a ATBD
-
units:
meters
/gt2l/geolocation/solar_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The azimuth of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from North and is positive towards East. ATL03g provides this value in radians; it is converted to degrees for ATL03 output.
-
long_name:
solar azimuth
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees_east
/gt2l/geolocation/surf_type[
delta_time=
0
..163492]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Flags describing which surface types this interval is associated with. 0=not type, 1=is type. Order of array is land, ocean, sea ice, land ice, inland water.
-
flag_meanings:
not_type is_type
-
flag_values:
0, 1
-
long_name:
Surface Type
-
source:
ATL03 ATBD, Section 4
-
units:
1
-
valid_max:
1
-
valid_min:
0
/gt2l/geolocation/sigma_lat[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic Latitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
latitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt2l/geolocation/tx_pulse_width_lower[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the lower threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Lower Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt2l/geolocation/sigma_along[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated cartesian along-track uncertainanty (1-sigma) for the reference photon
-
long_name:
along-track geolocation uncertainity
-
source:
ATL03G ATBD
-
units:
meters
/gt2l/geolocation/tx_pulse_skew_est[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the averages of the lower and upper threshold crossing times. This is an estimate of the transmit pulse skew.
-
long_name:
Transmit Pulse Skew Estimate
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt2l/geolocation/tx_pulse_energy[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
physicalMeasurement
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average transmit pulse energy, measured by the internal laser energy monitor, split into per-beam measurements.
-
long_name:
Transmit Pulse Energy
-
source:
ATL02 ATBD, Section 7.2
-
units:
Joules
/gt2l/geolocation/tx_pulse_width_upper[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the upper threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Upper Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt2l/geolocation/sigma_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated height uncertainty (1-sigma) for the reference photon bounce point.
-
long_name:
height uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt2l/geolocation/podppd_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
0
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Composite POD/PPD flag that indicates the quality of input geolocation products for the specific ATL03 segment. A non-zero value may indicate that geolocation solutions are degraded. The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE.
-
flag_meanings:
nominal pod_degrade ppd_degrade podppd_degrade
-
flag_values:
0, 1, 2, 3
-
long_name:
POD_PPD Flag
-
source:
ANC04, ANC05
-
units:
1
-
valid_max:
3
-
valid_min:
0
/gt2l/geolocation/velocity_sc[
delta_time=
0
..163492]
[
ds_xyz=
0
..2]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Spacecraft velocity components (east component, north component, up component) an observer on the ground would measure. While values are common to all beams, this parameter is naturally produced as part of geolocation.
-
long_name:
spacecraft velocity
-
source:
ATL03G ATBD
-
units:
meters/second
/gt2l/geolocation/full_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be fully saturated.
-
long_name:
Full Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt2l/geolocation/segment_id[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
A 7 digit number identifiying the along-track geolocation segment number. These are sequential, starting with 1 for the first segment after an ascending equatorial crossing node.
-
long_name:
along-track segment ID number.
-
source:
ATL03 ATBD, Section 3.1
-
units:
1
/gt2l/geolocation/near_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be nearly saturated.
-
long_name:
Near Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt2l/geolocation/reference_photon_lat[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Latitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Latitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt2l/geolocation/solar_elevation[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The elevation of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from the East-North plane and is positive Up. ATL03g provides this value in radians; it is converted to degress for ATL03 output.
-
long_name:
solar elevation
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees
/gt2l/geolocation/bounce_time_offset[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the transmit time and the ground bounce time of the reference photons.
-
long_name:
ground bounce time offset
-
source:
ATL03 ATBD, Section 3.3
-
units:
seconds
/gt2l/geolocation/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
reference_photon_lat, reference_photon_lon
-
description:
Transmit time of the reference photon, measured in seconds from the atlas_sdp_gps_epoch. If there is no reference photon, this time corresponds to the approximate mid-point time associated with the along-track geolocation segment edge. 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:
Delta Time
-
source:
Derived
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/geolocation/reference_photon_index[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Index of the reference photon within the set of photons grouped within in segment. To recover the position of the reference photon within the photon-rate arrays, add ref_ph_ndx to the corresponding ph_ndx_beg and subtract 1. If no reference photon was selected, this value will indicate that the reference photon defaulted to the first photon. In the case of no photons within the segment (segment_ph_cnt=0), the value should be 0.
-
long_name:
Reference Photon Index
-
source:
ATL03 ATBD, Section 3.2
-
units:
counts
/gt2l/geolocation/altitude_sc[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
_FillValue:
1.7976931348623157e+308
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Height of the spacecraft above the WGS84 ellipsoid.
-
long_name:
Altitude
-
source:
ATL03g ATBD, Section 3.4
-
units:
meters
/gt2l/geolocation/segment_dist_x[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Along-track distance from the equator crossing to the start of the 20 meter geolocation segment.
-
long_name:
Segment Distance from EQC
-
source:
Derived
-
units:
meters
/gt2l/geolocation/neutat_delay_total[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Total neutral atmosphere delay correction (wet+dry).
-
long_name:
Total Neutral Atmospheric Delay
-
source:
ATL03a ATBD
-
units:
meters
/gt2l/geophys_corr/tide_oc_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
description:
Surface deformation of the Earth due to loading from the centrifugal effect of polar motion upon the oceans (-2 to 2 mm).
-
long_name:
Ocean Pole Tide
-
source:
ATL03 ATBD, Section 6.3.6
-
units:
meters
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
/gt2l/geophys_corr/dem_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
127
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Indicates source of the DEM height. Values: 0=None, 1=Arctic, 2=GMTED, 3=MSS, 4=Antarctic.
-
flag_meanings:
none arctic gmted mss antarctic
-
flag_values:
0, 1, 2, 3, 4
-
long_name:
dem source flag
-
source:
ATL03 ATBD Section 6.3
-
units:
1
-
valid_max:
4
-
valid_min:
0
/gt2l/geophys_corr/tide_ocean[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium). This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Ocean Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt2l/geophys_corr/tide_earth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Tides
-
long_name:
Earth Tide
-
source:
ATL03 ATBD, Section 6.3.3
-
units:
meters
/gt2l/geophys_corr/dac[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect. This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Dynamic Atmosphere Correction
-
source:
ATL03 ATBD, Section 6.3.2
-
units:
meters
/gt2l/geophys_corr/tide_load[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
-
long_name:
Load Tide
-
source:
ATL03 ATBD, Section 6.3.4
-
units:
meters
/gt2l/geophys_corr/dem_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Best available DEM (in priority of Arctic/Antarctic/GMTED/MSS) value at the location of the reference photon.
-
long_name:
DEM Height
-
source:
ATL03 ATBD Section 6.3
-
units:
meters
/gt2l/geophys_corr/tide_equilibrium[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). This correction is not applied to the photon heights and is provided only as a supplemental information.
-
long_name:
Long Period Equilibrium Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt2l/geophys_corr/geoid[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Geoid height above WGS-84 reference ellipsoid (range -107 to 86m). Not applied on the product; requested by higher-level products.
-
long_name:
Geoid
-
source:
ATL03 ATBD, Section 6.3.8
-
units:
meters
/gt2l/geophys_corr/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
description:
Elapsed seconds from the ATLAS SDP GPS Epoch, corresponding to the transmit time of the reference photon. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/geophys_corr/tide_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
-
long_name:
Solid Earth Pole Tide
-
source:
ATL03 ATBD, Section 6.3.5
-
units:
meters
/gt2l/signal_find_output/ocean/bckgrd_mean[
delta_time=
0
..61856]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/ocean/bckgrd_sigma[
delta_time=
0
..61856]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/ocean/t_pc_delta[
delta_time=
0
..61856]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2l/signal_find_output/ocean/delta_time[
delta_time=
0
..61856]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/signal_find_output/ocean/z_pc_delta[
delta_time=
0
..61856]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2l/signal_find_output/sea_ice/bckgrd_mean[
delta_time=
0
..62228]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/sea_ice/bckgrd_sigma[
delta_time=
0
..62228]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/sea_ice/t_pc_delta[
delta_time=
0
..62228]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2l/signal_find_output/sea_ice/delta_time[
delta_time=
0
..62228]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/signal_find_output/sea_ice/z_pc_delta[
delta_time=
0
..62228]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2l/signal_find_output/land_ice/bckgrd_mean[
delta_time=
0
..10335]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/land_ice/bckgrd_sigma[
delta_time=
0
..10335]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/land_ice/t_pc_delta[
delta_time=
0
..10335]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2l/signal_find_output/land_ice/delta_time[
delta_time=
0
..10335]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/signal_find_output/land_ice/z_pc_delta[
delta_time=
0
..10335]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2l/signal_find_output/land/bckgrd_mean[
delta_time=
0
..4225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/land/bckgrd_sigma[
delta_time=
0
..4225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/land/t_pc_delta[
delta_time=
0
..4225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2l/signal_find_output/land/delta_time[
delta_time=
0
..4225]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/signal_find_output/land/z_pc_delta[
delta_time=
0
..4225]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2l/signal_find_output/inlandwater/bckgrd_mean[
delta_time=
0
..4374]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/inlandwater/bckgrd_sigma[
delta_time=
0
..4374]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt2l/signal_find_output/inlandwater/t_pc_delta[
delta_time=
0
..4374]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt2l/signal_find_output/inlandwater/delta_time[
delta_time=
0
..4374]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/signal_find_output/inlandwater/z_pc_delta[
delta_time=
0
..4374]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt2l/heights/ph_id_count[
delta_time=
0
..2.975195E6]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The photon event counter is part of photon ID and counts from 1 for each channel until reset by laser pulse counter.
-
long_name:
photon event counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt2l/heights/lat_ph[
delta_time=
0
..2.975195E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lon_ph
-
description:
Latitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Latitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt2l/heights/dist_ph_along[
delta_time=
0
..2.975195E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Along-track distance in a segment projected to the ellipsoid of the received photon, based on the Along-Track Segment algorithm. Total along track distance can be found by adding this value to the sum of segment lengths measured from the start of the most recent reference groundtrack.
-
long_name:
Distance from equator crossing.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt2l/heights/signal_conf_ph[
delta_time=
0
..2.975195E6]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Confidence level associated with each photon event selected as signal. 0=noise. 1=added to allow for buffer but algorithm classifies as background; 2=low; 3=med; 4=high). This parameter is a 5xN array where N is the number of photons in the granule, and the 5 rows indicate signal finding for each surface type (in order: land, ocean, sea ice, land ice and inland water). Events not associated with a specific surface type have a confidence level of -1. Events evaluated as TEP returns have a confidence level of -2.
-
flag_meanings:
possible_tep not_considered noise buffer low medium high
-
flag_values:
-2, -1, 0, 1, 2, 3, 4
-
long_name:
Photon Signal Confidence
-
source:
ATL03 ATBD, Section 5, Conf
-
units:
1
-
valid_max:
4
-
valid_min:
-2
/gt2l/heights/ph_id_pulse[
delta_time=
0
..2.975195E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The laser pulse counter is part of photon ID and counts from 1 to 200 and is reset for each new major frame.
-
long_name:
laser pulse counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt2l/heights/h_ph[
delta_time=
0
..2.975195E6]
(Type is Float32)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Height of each received photon, relative to the WGS-84 ellipsoid including the geophysical corrections noted in Section 6. Please note that neither the geoid, ocean tide nor the dynamic atmosphere (DAC) corrections are applied to the ellipsoidal heights.
-
long_name:
Photon WGS84 Height
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
height
-
units:
meters
/gt2l/heights/ph_id_channel[
delta_time=
0
..2.975195E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Channel number assigned for each received photon event. This is part of the photon ID. Values range from 1 to 120 to span all channels and rise/fall edges. Values 1 to 60 are for falling edge; PCE1 (1 to 20), PCE 2 (21 to 40) and PCE3 (41 to 60). Values 61 to 120 are for rising edge; PCE1 (61 to 80), PCE 2 (81 to 100) and PC3 (101 to 120).
-
long_name:
Receive channel id
-
source:
Derived as part of Photon ID
-
units:
1
-
valid_max:
120
-
valid_min:
1
/gt2l/heights/lon_ph[
delta_time=
0
..2.975195E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lat_ph
-
description:
Longitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Longitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt2l/heights/delta_time[
delta_time=
0
..2.975195E6]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
lat_ph lon_ph
-
description:
The transmit time of a given photon, measured in seconds from the ATLAS Standard Data Product Epoch. Note that multiple received photons associated with a single transmit pulse will have the same delta_time. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt2l/heights/pce_mframe_cnt[
delta_time=
0
..2.975195E6]
(Type is UInt32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The major frame counter is read from the digital flow controller in a given PCE card. The counter identifies individual major frames across diag and science packets. Used as part of the photon ID.
-
long_name:
PCE Major frame counter
-
source:
Retained from prior a_alt_science_ph packet
-
units:
counts
/gt2l/heights/dist_ph_across[
delta_time=
0
..2.975195E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Across-track distance projected to the ellipsoid of the received photon from the reference ground track. This is based on the Along-Track Segment algorithm described in Section 3.1.
-
long_name:
Distance off RGT.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/ancillary_data/release[
0
..0]
(Type is String)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is String)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Float64)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Float64)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is String)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
UTC (in CCSDS-A format) of the last data point within the granule.
-
long_name:
End UTC Time of Granule (CCSDS-A, Actual)
-
source:
Derived
-
units:
1
/ancillary_data/control[
0
..0]
(Type is String)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
PGE-specific control file used to generate this granule. To re-use, replace breaks (BR) with linefeeds.
-
long_name:
Control File
-
source:
Operations
-
units:
1
/ancillary_data/start_gpssow[
0
..0]
(Type is Float64)
-
attributes
-
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[
0
..0]
(Type is String)
-
attributes
-
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/end_cycle[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
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.
-
long_name:
Ending Cycle
-
source:
Derived
-
units:
1
-
valid_max:
99
-
valid_min:
0
/ancillary_data/granule_start_utc[
0
..0]
(Type is String)
-
attributes
-
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[
start_delta_time=
0
..0]
(Type is Float64)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is String)
-
attributes
-
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/end_gpsweek[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Float64)
-
attributes
-
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/start_region[
0
..0]
(Type is Int32)
-
attributes
-
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[
0
..0]
(Type is Int32)
-
attributes
-
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
/ancillary_data/calibrations/ds_channel[
ds_channel=
0
..19]
(Type is Int8)
-
attributes
-
description:
Dimension scale for ATLAS PCE channels (1-16=strong, 17-20=weak)
-
long_name:
Channel
-
units:
1
-
valid_max:
20
-
valid_min:
1
-
contentType:
referenceInformation
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/cal34_product[
0
..5]
(Type is String)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Name of ATLAS CAL Products containing the calibration data
-
long_name:
CAL Product Name
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1l/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1l/rad_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Radiometric Correction (width, strength, deadtime)
-
long_name:
Radiometric Correction
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1l/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1l/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL34
-
units:
ns
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2l/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2l/rad_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Radiometric Correction (width, strength, deadtime)
-
long_name:
Radiometric Correction
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2l/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2l/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL34
-
units:
ns
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1r/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1r/rad_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Radiometric Correction (width, strength, deadtime)
-
long_name:
Radiometric Correction
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1r/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt1r/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL34
-
units:
ns
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2r/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2r/rad_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Radiometric Correction (width, strength, deadtime)
-
long_name:
Radiometric Correction
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2r/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt2r/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL34
-
units:
ns
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3l/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3l/rad_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Radiometric Correction (width, strength, deadtime)
-
long_name:
Radiometric Correction
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3l/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3l/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL34
-
units:
ns
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3r/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3r/rad_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Radiometric Correction (width, strength, deadtime)
-
long_name:
Radiometric Correction
-
source:
CAL34
-
units:
1
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3r/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/dead_time_radiometric_signal_loss/gt3r/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL34
-
units:
ns
/ancillary_data/calibrations/first_photon_bias/cal19_product[
0
..5]
(Type is String)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Name of ATLAS CAL Products containing the calibration data
-
long_name:
CAL Product Name
-
source:
CAL19
-
units:
1
/ancillary_data/calibrations/first_photon_bias/gt1l/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/first_photon_bias/gt1l/ffb_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
First Photon Bias Correction (width, strength, deadtime) in picoseconds.
-
long_name:
FFB Correction
-
source:
CAL19
-
units:
ps
/ancillary_data/calibrations/first_photon_bias/gt1l/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/first_photon_bias/gt1l/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL19
-
units:
ns
/ancillary_data/calibrations/first_photon_bias/gt2l/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/first_photon_bias/gt2l/ffb_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
First Photon Bias Correction (width, strength, deadtime) in picoseconds.
-
long_name:
FFB Correction
-
source:
CAL19
-
units:
ps
/ancillary_data/calibrations/first_photon_bias/gt2l/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/first_photon_bias/gt2l/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL19
-
units:
ns
/ancillary_data/calibrations/first_photon_bias/gt1r/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/first_photon_bias/gt1r/ffb_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
First Photon Bias Correction (width, strength, deadtime) in picoseconds.
-
long_name:
FFB Correction
-
source:
CAL19
-
units:
ps
/ancillary_data/calibrations/first_photon_bias/gt1r/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/first_photon_bias/gt1r/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL19
-
units:
ns
/ancillary_data/calibrations/first_photon_bias/gt2r/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/first_photon_bias/gt2r/ffb_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
First Photon Bias Correction (width, strength, deadtime) in picoseconds.
-
long_name:
FFB Correction
-
source:
CAL19
-
units:
ps
/ancillary_data/calibrations/first_photon_bias/gt2r/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/first_photon_bias/gt2r/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL19
-
units:
ns
/ancillary_data/calibrations/first_photon_bias/gt3l/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/first_photon_bias/gt3l/ffb_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
First Photon Bias Correction (width, strength, deadtime) in picoseconds.
-
long_name:
FFB Correction
-
source:
CAL19
-
units:
ps
/ancillary_data/calibrations/first_photon_bias/gt3l/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/first_photon_bias/gt3l/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL19
-
units:
ns
/ancillary_data/calibrations/first_photon_bias/gt3r/dead_time[
0
..5]
(Type is Float32)
/ancillary_data/calibrations/first_photon_bias/gt3r/ffb_corr[
0
..5]
[
0
..159]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
First Photon Bias Correction (width, strength, deadtime) in picoseconds.
-
long_name:
FFB Correction
-
source:
CAL19
-
units:
ps
/ancillary_data/calibrations/first_photon_bias/gt3r/strength[
0
..5]
[
0
..159]
(Type is Float64)
/ancillary_data/calibrations/first_photon_bias/gt3r/width[
0
..5]
[
0
..497]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Apparent width (width, deadtime)
-
long_name:
Apparent Width
-
source:
CAL19
-
units:
ns
/ancillary_data/calibrations/low_link_impulse_response/laser[
0
..0]
(Type is Int32)
/ancillary_data/calibrations/low_link_impulse_response/hist_x[
hist_x=
0
..1999]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Histogram bin x-values
-
long_name:
Histogram Bin X Values
-
source:
CAL20
-
units:
1
/ancillary_data/calibrations/low_link_impulse_response/mode[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Laser Power Setting
-
long_name:
Laser Power Setting
-
source:
CAL20
-
units:
1
/ancillary_data/calibrations/low_link_impulse_response/return_source[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
long_name:
Return Source
-
description:
Source of the events from which the data are derived.
-
flag_meanings:
none tep maat echo
-
flag_values:
0, 1, 2, 3
-
source:
CAL20
-
units:
1
-
valid_max:
3
-
valid_min:
0
/ancillary_data/calibrations/low_link_impulse_response/cal20_product[
0
..0]
(Type is String)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Name of ATLAS CAL Product containing the calibration data
-
long_name:
CAL Product Name
-
source:
CAL20
-
units:
1
/ancillary_data/calibrations/low_link_impulse_response/num_bins[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Number of bins in the histogram
-
long_name:
Number of Bins
-
source:
CAL20
-
units:
1
/ancillary_data/calibrations/low_link_impulse_response/temperature[
0
..0]
(Type is Float32)
/ancillary_data/calibrations/low_link_impulse_response/bin_width[
0
..0]
(Type is Float32)
/ancillary_data/calibrations/low_link_impulse_response/side[
0
..0]
(Type is Int32)
/ancillary_data/calibrations/low_link_impulse_response/gt1r/hist[
ds_channel=
0
..19]
[
hist_x=
0
..1999]
(Type is Float64)
/ancillary_data/calibrations/low_link_impulse_response/gt2r/hist[
ds_channel=
0
..19]
[
hist_x=
0
..1999]
(Type is Float64)
/ancillary_data/calibrations/low_link_impulse_response/gt1l/hist[
ds_channel=
0
..19]
[
hist_x=
0
..1999]
(Type is Float64)
/ancillary_data/calibrations/low_link_impulse_response/gt3l/hist[
ds_channel=
0
..19]
[
hist_x=
0
..1999]
(Type is Float64)
/ancillary_data/calibrations/low_link_impulse_response/gt2l/hist[
ds_channel=
0
..19]
[
hist_x=
0
..1999]
(Type is Float64)
/ancillary_data/calibrations/low_link_impulse_response/gt3r/hist[
ds_channel=
0
..19]
[
hist_x=
0
..1999]
(Type is Float64)
/ancillary_data/calibrations/dead_time/temperature[
0
..0]
(Type is Float32)
/ancillary_data/calibrations/dead_time/cal42_product[
0
..0]
(Type is String)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Name of ATLAS CAL Product containing the calibration data
-
long_name:
CAL Product Name
-
source:
CAL42
-
units:
1
/ancillary_data/calibrations/dead_time/side[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
A or B side of the detector bank
-
flag_meanings:
A B
-
flag_values:
1, 2
-
long_name:
Detector Bank Side
-
source:
CAL42
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/calibrations/dead_time/gt1r/dead_time[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt1r/sigma[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt2r/dead_time[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt2r/sigma[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt1l/dead_time[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt1l/sigma[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt3l/dead_time[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt3l/sigma[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt2l/dead_time[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt2l/sigma[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt3r/dead_time[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/calibrations/dead_time/gt3r/sigma[
ds_channel=
0
..19]
(Type is Float64)
/ancillary_data/atlas_engineering/spd_ab_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Indicates if the active Start Pulse Detector (SPD) is side a (1) or side b (2).
-
flag_meanings:
a b
-
flag_values:
1, 2
-
long_name:
SPD A or B
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/tams_ab_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Indicates if the active TAMS is side a (1) or side b (2).
-
flag_meanings:
a b
-
flag_values:
1, 2
-
long_name:
TAMS Side A or B
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/ds_gt[
ds_gt=
0
..5]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
description:
Dimension scale for ATLAS Groundtracks (gt1l, gt1r, gt2l, gt2r, gt3l, gt3r)
-
flag_meanings:
gt1l gt1r gt2l gt2r gt3l gt3r
-
flag_values:
1, 2, 3, 4, 5, 6
-
long_name:
GT Index
-
units:
1
-
valid_max:
6
-
valid_min:
1
/ancillary_data/atlas_engineering/det_ab_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Indicates if the active detector (DET) is side A (1) or side B (2).
-
flag_meanings:
a b
-
flag_values:
1, 2
-
long_name:
Detector Side, A or B
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/lrs_ab_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
flag_meanings:
a b
-
description:
Indicates if the active LRS is side A (1) or side B (2).
-
flag_values:
1, 2
-
long_name:
LRS Side A or B
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/ds_stat[
ds_stat=
0
..3]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
description:
Dimension scale for statistics in the order mean, sdev, min, max
-
flag_meanings:
mean sdev min max
-
flag_values:
1, 2, 3, 4
-
long_name:
Stat Index
-
units:
1
-
valid_max:
5
-
valid_min:
1
/ancillary_data/atlas_engineering/laser_12_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
flag_meanings:
1 2
-
description:
Indicates if the active Laser is laser 1 or laser 2.
-
flag_values:
1, 2
-
long_name:
Laser 1 or Laser 2
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/pdu_ab_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
flag_meanings:
a b
-
description:
Indicates if the active PDU is side a (1) or side b (2).
-
flag_values:
1, 2
-
long_name:
PDU Side A or B
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/ph_uncorrelated_error[
ds_gt=
0
..5]
[
start_delta_time=
0
..0]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The estimate of uncorrelated height error. This is a six-valued array mapped onto gt1l, gt1r, gt2l, gt2r, gt3l, gt3r using the sc_orient parameter.
-
long_name:
Uncorrelated Error
-
source:
ATL03 ATBD, Section 7.7.2
-
units:
meters
/ancillary_data/atlas_engineering/hvpc_ab_flag[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
flag_meanings:
a b
-
description:
Indicates if the active High Voltage Power Converter (HVPC) is side A (1) or side B (2).
-
flag_values:
1, 2
-
long_name:
HVPC Side, A or B
-
source:
Derived, L1B ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/atlas_engineering/transmit/tx_pulse_distribution[
ds_gt=
0
..5]
[
start_delta_time=
0
..0]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The fraction of the transmit pulse energy in a given beam, based on pre-launch calibration. This is a six-valued array mapped onto gt1l, gt1r, gt2l, gt2r, gt3l, gt3r using the sc_orient parameter.
-
long_name:
transmit pulse energy distribution
-
source:
ATL03 ATBD, Section 7.2
-
units:
1
/ancillary_data/atlas_engineering/transmit/tx_pulse_skew_est[
start_delta_time=
0
..0]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The difference between the means of the lower and upper threshold crossing times; a positive value corresponds to a positive skew in the pulse, and conversely for a negative value.
-
long_name:
transmit pulse shape skew
-
source:
ATL02, described in ATL03 ATBD Section 7.2.1
-
units:
seconds
/ancillary_data/atlas_engineering/transmit/tx_pulse_thresh_lower[
start_delta_time=
0
..0]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The lower threshold setting of the start pulse detector. The threshold crossing times are used to determine the start pulse time, and estimate the start pulse shape. If this setting changes during a given granule, this parameter becomes two-valued.
-
long_name:
transmit pulse lower threshold
-
source:
ATL03 ATBD, Section 7.2
-
units:
volts
/ancillary_data/atlas_engineering/transmit/tx_pulse_thresh_upper[
start_delta_time=
0
..0]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The upper threshold setting of the start pulse detector. The threshold crossing times are used to determine the start pulse time, and estimate the start pulse shape. If this setting changes during a given granule, this parameter becomes two-valued.
-
long_name:
transmit pulse upper threshold
-
source:
ATL03 ATBD, Section 7.2
-
units:
volts
/ancillary_data/atlas_engineering/transmit/tx_pulse_width_lower[
start_delta_time=
0
..0]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The difference between the two crossing times of the transmit pulse
-
long_name:
lower threshold crossing time difference
-
source:
ATL02, described in ATL03 ATBD Section 7.2.1
-
units:
seconds
/ancillary_data/atlas_engineering/transmit/tx_pulse_width_upper[
start_delta_time=
0
..0]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The difference between the two crossing times of the transmit pulse
-
long_name:
upper threshold crossing time difference
-
source:
ATL02, described in ATL03 ATBD Section 7.2.1
-
units:
seconds
/ancillary_data/atlas_engineering/transmit/tx_pulse_energy[
ds_gt=
0
..5]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The mean, standard deviation, minimum and maximum values of the transmit energy for each beam as reported by the start pulse detector, averaged over a given ATL03 granule. This is a 6x4 array mapped onto gt1l, gt1r, gt2l, gt2r, gt3l, gt3r using the sc_orient parameter.
-
long_name:
ATLAS Transmit Energy
-
source:
ATL03 ATBD Section 7.2.1
-
units:
joules
/ancillary_data/atlas_engineering/receiver/rx_bckgrd_sensitivity[
ds_gt=
0
..5]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Per-beam receiver background sensitivity. This is a six-valued array mapped onto gt1l, gt1r, gt2l, gt2r, gt3l, gt3r using the sc_orient parameter.
-
long_name:
Receiver background sensivitiy
-
source:
ATL02 ATBD, Sections 5.3.2
-
units:
events/joule
/ancillary_data/atlas_engineering/receiver/rx_return_sensitivity[
ds_gt=
0
..5]
[
ds_stat=
0
..3]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Per-beam receiver return sensitivity. This is a six-valued array mapped onto gt1l, gt1r, gt2l, gt2r, gt3l, gt3r using the sc_orient parameter.
-
long_name:
Receiver return sensitivity
-
source:
ATL02 ATBD, Sections 5.3.2
-
units:
events/joule
/ancillary_data/gt1r/signal_find_input/sig_find_t_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time increment the algorithm uses to step through the photon cloud in a granule. Histograms are formed at each sig_find_t_inc interval to identify signal photon events.
-
long_name:
Histogram time increment
-
source:
ATL03, Section 5, _time
-
units:
seconds
/ancillary_data/gt1r/signal_find_input/alpha_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Maximum slope allowed for slant histogram; if larger than this then don
-
long_name:
Maximum Slope
-
source:
ATL03, Section 5, _max
-
units:
radians
/ancillary_data/gt1r/signal_find_input/delta_z_bg[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Width of a height bin in each atmospheric histogram, Ha, if calculating Ha from the photon cloud. Surface-type dependent.
-
long_name:
Histogram height bin size for noise calculation from photon cloud
-
source:
ATL03, Section 5, _zBG
/ancillary_data/gt1r/signal_find_input/e_linfit_edit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of linear fit to signal photons used to edit out noise during running linear fit edit of outliers.
-
long_name:
Multiplier of STD of linear fit
-
source:
ATL03, Section 5, e_linfit_edit
-
units:
1
/ancillary_data/gt1r/signal_find_input/e_m[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of the number of background photon events per bin used in determining signal photon threshold. Surface-type dependent.
-
long_name:
Multiplier of STD of background
-
source:
ATL03, Section 5, em
-
units:
1
/ancillary_data/gt1r/signal_find_input/snrlow[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio below which all selected signal has low confidence.
-
long_name:
Signal to noise ratio low
-
source:
ATL03, Section 5, snrlow
-
units:
1
/ancillary_data/gt1r/signal_find_input/nslw_v[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half the value of the height window used for slant histogramming relative to the surface used when varying the surface slope, alpha, to fill large gaps. Surface-type dependent.
-
long_name:
Half height for variable slope slant histogramming
-
source:
ATL03, Section 5, nslw_v
-
units:
meters
/ancillary_data/gt1r/signal_find_input/nphot_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons over which to perform a linear fit to estimate the surface profile across a gap. Surface-type dependent.
-
long_name:
Minimum number of photons to fill gap
-
source:
ATL03, Section 5, Nphotmin
-
units:
counts
/ancillary_data/gt1r/signal_find_input/delta_zmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height bin size for histogramming for first sweep. Surface-type dependent.
-
long_name:
Minimum height bin size
-
source:
ATL03, Section 5, _zmin
-
units:
meters
/ancillary_data/gt1r/signal_find_input/delta_t_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Maximum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Maximum time
-
source:
ATL03, Section 5, _tmax
/ancillary_data/gt1r/signal_find_input/lslant_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform slant histogramming for the strong beam. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
Flag to request slant histogramming for strong beams.
-
source:
ATL03, Section 5, lslant
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt1r/signal_find_input/n_delta_z2[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmax1 and delta_zmax2. Surface-type dependent.
-
long_name:
number of increments in z2
-
source:
ATL03, Section 5, n_z2
-
units:
counts
/ancillary_data/gt1r/signal_find_input/e_m_mult[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of e_m used to determine Thsig2, threshold for singular bins. Surface-type dependent.
-
long_name:
Multiplier of STD of e_m
-
source:
ATL03, Section 5, em_mult
-
units:
1
/ancillary_data/gt1r/signal_find_input/delta_t_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Minimum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Minimum time
-
source:
ATL03, Section 5, _tmin
/ancillary_data/gt1r/signal_find_input/r2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of (maximum number of photons in any one bin of contiguous signal bins)/(Maximum number of photons in largest bin) in order to accept a group of potential signal bins as signal. Surface-type dependent.
-
long_name:
Minimum ratio2
-
source:
ATL03, Section 5, R2
-
units:
1
/ancillary_data/gt1r/signal_find_input/snrmed[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio above which all selected signal has high confidence. Selected signal with signal to noise ratio between snrlow and snrmed is marked as medium confidence.
-
long_name:
Signal to noise ratio medium
-
source:
ATL03, Section 5, snrmed
-
units:
1
/ancillary_data/gt1r/signal_find_input/n_delta_z1[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmin and delat_zmax1. Surface-type dependent.
-
long_name:
number of increments in z1
-
source:
ATL03, Section 5, n_z1
-
units:
counts
/ancillary_data/gt1r/signal_find_input/min_fit_time_fact[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The factor to multiply DTIME by to obtain the minimum time over which to fit a line to a height profile to calculate the local slope using running linear fits, min_fit_time.
-
long_name:
minimum fit time factor
-
source:
ATL03, Section 5, min_fit_time_fact
-
units:
seconds
/ancillary_data/gt1r/signal_find_input/pc_bckgrd_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then always use the photon cloud to calculate the background photon rate, if false only use the photon cloud in the absence of the atmospheric histogram. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
calculated background rate flag
-
source:
ATL03, Section 5, Lpcbg
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt1r/signal_find_input/t_gap_big[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
For time gaps less than this value, slant histogramming is performed relative to the linear slope calculated from the surrounding signal. For time gaps greater than or equal to this value the slope is varied when performing slant histogramming. Surface-type dependent.
-
long_name:
Gap size criteria
-
source:
ATL03, Section 5, tgapbig
-
units:
seconds
/ancillary_data/gt1r/signal_find_input/e_a[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of Ha_sigma used to determine which bins in the atmospheric histogram may contain signal photon events. Surface-type dependent.
-
long_name:
Multiplier of Ha_sigma
-
source:
ATL03, Section 5, ea
-
units:
1
/ancillary_data/gt1r/signal_find_input/delta_zmax2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
meters
-
description:
Maximum height bin size for histogramming for second sweep. Surface-type dependent.
-
long_name:
Maximum height bin size 2
-
source:
ATL03, Section 5, _zmax2
/ancillary_data/gt1r/signal_find_input/nslw[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half of the value of the height window used for slant histogramming relative to the surface defined by the linear fit to the surrounding photons at slope, alpha. Surface-type dependent.
-
long_name:
half height for slant histogramming
-
source:
ATL03, Section 5, nslw
-
units:
meters
/ancillary_data/gt1r/signal_find_input/e_linfit_slant[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of sigma_linfit, the standard deviation of the residuals between the actual photon events used to estimate the surface using a linear fit; all photons with height > e_linfit_slant
-
long_name:
Multiplier of sigma linfit
-
source:
ATL03, Section 5, e_linfit_slant
-
units:
1
/ancillary_data/gt1r/signal_find_input/addpad_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) that if true (=1) then identify additional photon events as padding to achieve htspanin for each time interval sig_find_t_inc.
-
long_name:
Additional photon flag
-
source:
ATL03, Section 5, Addpad
-
units:
1
/ancillary_data/gt1r/signal_find_input/nbin_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of bins in a histogram required for the algorithm to be able to process the histogram.
-
long_name:
Minimum number of bins
-
source:
ATL03, Section 5, Nbinmin
-
units:
counts
/ancillary_data/gt1r/signal_find_input/htspanmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height span for each time interval of photons with confidence flag > 0. If the height span is < htspanmin then all photons not previously selected within +/- htspanmin/2 of the median height of the signal photons selected are marked with a confidence flag of 1. Surface-type dependent.
-
long_name:
Minimum height span
-
source:
ATL03, Section 5, Htspanmin
-
units:
meters
/ancillary_data/gt1r/signal_find_input/alpha_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Increment by which the slope is varied for slant histogramming over large gaps
-
long_name:
Slope Increment
-
source:
ATL03, Section 5, _inc
-
units:
radians
/ancillary_data/gt1r/signal_find_input/out_edit_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform an n _ edit on a running linear fit to identified signal to remove outliers. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
outlier edit flag
-
source:
ATL03, Section 5, Ledit
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt1r/signal_find_input/delta_t_gap_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum size of a time gap in the height profile over which to use variable slope slant histogramming.
-
long_name:
Mimimum delta time gap
-
source:
ATL03, Section 5, _time_gapmin
-
units:
seconds
/ancillary_data/gt1r/signal_find_input/delta_t_lin_fit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time span over which to perform a running linear fit to identified signal photon events when editing outliers. Surface type dependent.
-
long_name:
Linear fit time increment
-
source:
ATL03, Section 5, _t_linfit_edit
-
units:
seconds
/ancillary_data/gt1r/signal_find_input/r[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of max number of photons in histogram bin to mean noise value that must exist to consider a bin a signal bin.
-
long_name:
Minimum ratio
-
source:
ATL03, Section 5, R
-
units:
1
/ancillary_data/gt2r/signal_find_input/sig_find_t_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time increment the algorithm uses to step through the photon cloud in a granule. Histograms are formed at each sig_find_t_inc interval to identify signal photon events.
-
long_name:
Histogram time increment
-
source:
ATL03, Section 5, _time
-
units:
seconds
/ancillary_data/gt2r/signal_find_input/alpha_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Maximum slope allowed for slant histogram; if larger than this then don
-
long_name:
Maximum Slope
-
source:
ATL03, Section 5, _max
-
units:
radians
/ancillary_data/gt2r/signal_find_input/delta_z_bg[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Width of a height bin in each atmospheric histogram, Ha, if calculating Ha from the photon cloud. Surface-type dependent.
-
long_name:
Histogram height bin size for noise calculation from photon cloud
-
source:
ATL03, Section 5, _zBG
/ancillary_data/gt2r/signal_find_input/e_linfit_edit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of linear fit to signal photons used to edit out noise during running linear fit edit of outliers.
-
long_name:
Multiplier of STD of linear fit
-
source:
ATL03, Section 5, e_linfit_edit
-
units:
1
/ancillary_data/gt2r/signal_find_input/e_m[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of the number of background photon events per bin used in determining signal photon threshold. Surface-type dependent.
-
long_name:
Multiplier of STD of background
-
source:
ATL03, Section 5, em
-
units:
1
/ancillary_data/gt2r/signal_find_input/snrlow[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio below which all selected signal has low confidence.
-
long_name:
Signal to noise ratio low
-
source:
ATL03, Section 5, snrlow
-
units:
1
/ancillary_data/gt2r/signal_find_input/nslw_v[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half the value of the height window used for slant histogramming relative to the surface used when varying the surface slope, alpha, to fill large gaps. Surface-type dependent.
-
long_name:
Half height for variable slope slant histogramming
-
source:
ATL03, Section 5, nslw_v
-
units:
meters
/ancillary_data/gt2r/signal_find_input/nphot_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons over which to perform a linear fit to estimate the surface profile across a gap. Surface-type dependent.
-
long_name:
Minimum number of photons to fill gap
-
source:
ATL03, Section 5, Nphotmin
-
units:
counts
/ancillary_data/gt2r/signal_find_input/delta_zmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height bin size for histogramming for first sweep. Surface-type dependent.
-
long_name:
Minimum height bin size
-
source:
ATL03, Section 5, _zmin
-
units:
meters
/ancillary_data/gt2r/signal_find_input/delta_t_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Maximum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Maximum time
-
source:
ATL03, Section 5, _tmax
/ancillary_data/gt2r/signal_find_input/lslant_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform slant histogramming for the strong beam. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
Flag to request slant histogramming for strong beams.
-
source:
ATL03, Section 5, lslant
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt2r/signal_find_input/n_delta_z2[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmax1 and delta_zmax2. Surface-type dependent.
-
long_name:
number of increments in z2
-
source:
ATL03, Section 5, n_z2
-
units:
counts
/ancillary_data/gt2r/signal_find_input/e_m_mult[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of e_m used to determine Thsig2, threshold for singular bins. Surface-type dependent.
-
long_name:
Multiplier of STD of e_m
-
source:
ATL03, Section 5, em_mult
-
units:
1
/ancillary_data/gt2r/signal_find_input/delta_t_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Minimum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Minimum time
-
source:
ATL03, Section 5, _tmin
/ancillary_data/gt2r/signal_find_input/r2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of (maximum number of photons in any one bin of contiguous signal bins)/(Maximum number of photons in largest bin) in order to accept a group of potential signal bins as signal. Surface-type dependent.
-
long_name:
Minimum ratio2
-
source:
ATL03, Section 5, R2
-
units:
1
/ancillary_data/gt2r/signal_find_input/snrmed[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio above which all selected signal has high confidence. Selected signal with signal to noise ratio between snrlow and snrmed is marked as medium confidence.
-
long_name:
Signal to noise ratio medium
-
source:
ATL03, Section 5, snrmed
-
units:
1
/ancillary_data/gt2r/signal_find_input/n_delta_z1[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmin and delat_zmax1. Surface-type dependent.
-
long_name:
number of increments in z1
-
source:
ATL03, Section 5, n_z1
-
units:
counts
/ancillary_data/gt2r/signal_find_input/min_fit_time_fact[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The factor to multiply DTIME by to obtain the minimum time over which to fit a line to a height profile to calculate the local slope using running linear fits, min_fit_time.
-
long_name:
minimum fit time factor
-
source:
ATL03, Section 5, min_fit_time_fact
-
units:
seconds
/ancillary_data/gt2r/signal_find_input/pc_bckgrd_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then always use the photon cloud to calculate the background photon rate, if false only use the photon cloud in the absence of the atmospheric histogram. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
calculated background rate flag
-
source:
ATL03, Section 5, Lpcbg
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt2r/signal_find_input/t_gap_big[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
For time gaps less than this value, slant histogramming is performed relative to the linear slope calculated from the surrounding signal. For time gaps greater than or equal to this value the slope is varied when performing slant histogramming. Surface-type dependent.
-
long_name:
Gap size criteria
-
source:
ATL03, Section 5, tgapbig
-
units:
seconds
/ancillary_data/gt2r/signal_find_input/e_a[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of Ha_sigma used to determine which bins in the atmospheric histogram may contain signal photon events. Surface-type dependent.
-
long_name:
Multiplier of Ha_sigma
-
source:
ATL03, Section 5, ea
-
units:
1
/ancillary_data/gt2r/signal_find_input/delta_zmax2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
meters
-
description:
Maximum height bin size for histogramming for second sweep. Surface-type dependent.
-
long_name:
Maximum height bin size 2
-
source:
ATL03, Section 5, _zmax2
/ancillary_data/gt2r/signal_find_input/nslw[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half of the value of the height window used for slant histogramming relative to the surface defined by the linear fit to the surrounding photons at slope, alpha. Surface-type dependent.
-
long_name:
half height for slant histogramming
-
source:
ATL03, Section 5, nslw
-
units:
meters
/ancillary_data/gt2r/signal_find_input/e_linfit_slant[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of sigma_linfit, the standard deviation of the residuals between the actual photon events used to estimate the surface using a linear fit; all photons with height > e_linfit_slant
-
long_name:
Multiplier of sigma linfit
-
source:
ATL03, Section 5, e_linfit_slant
-
units:
1
/ancillary_data/gt2r/signal_find_input/addpad_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) that if true (=1) then identify additional photon events as padding to achieve htspanin for each time interval sig_find_t_inc.
-
long_name:
Additional photon flag
-
source:
ATL03, Section 5, Addpad
-
units:
1
/ancillary_data/gt2r/signal_find_input/nbin_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of bins in a histogram required for the algorithm to be able to process the histogram.
-
long_name:
Minimum number of bins
-
source:
ATL03, Section 5, Nbinmin
-
units:
counts
/ancillary_data/gt2r/signal_find_input/htspanmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height span for each time interval of photons with confidence flag > 0. If the height span is < htspanmin then all photons not previously selected within +/- htspanmin/2 of the median height of the signal photons selected are marked with a confidence flag of 1. Surface-type dependent.
-
long_name:
Minimum height span
-
source:
ATL03, Section 5, Htspanmin
-
units:
meters
/ancillary_data/gt2r/signal_find_input/alpha_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Increment by which the slope is varied for slant histogramming over large gaps
-
long_name:
Slope Increment
-
source:
ATL03, Section 5, _inc
-
units:
radians
/ancillary_data/gt2r/signal_find_input/out_edit_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform an n _ edit on a running linear fit to identified signal to remove outliers. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
outlier edit flag
-
source:
ATL03, Section 5, Ledit
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt2r/signal_find_input/delta_t_gap_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum size of a time gap in the height profile over which to use variable slope slant histogramming.
-
long_name:
Mimimum delta time gap
-
source:
ATL03, Section 5, _time_gapmin
-
units:
seconds
/ancillary_data/gt2r/signal_find_input/delta_t_lin_fit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time span over which to perform a running linear fit to identified signal photon events when editing outliers. Surface type dependent.
-
long_name:
Linear fit time increment
-
source:
ATL03, Section 5, _t_linfit_edit
-
units:
seconds
/ancillary_data/gt2r/signal_find_input/r[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of max number of photons in histogram bin to mean noise value that must exist to consider a bin a signal bin.
-
long_name:
Minimum ratio
-
source:
ATL03, Section 5, R
-
units:
1
/ancillary_data/gt1l/signal_find_input/sig_find_t_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time increment the algorithm uses to step through the photon cloud in a granule. Histograms are formed at each sig_find_t_inc interval to identify signal photon events.
-
long_name:
Histogram time increment
-
source:
ATL03, Section 5, _time
-
units:
seconds
/ancillary_data/gt1l/signal_find_input/alpha_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Maximum slope allowed for slant histogram; if larger than this then don
-
long_name:
Maximum Slope
-
source:
ATL03, Section 5, _max
-
units:
radians
/ancillary_data/gt1l/signal_find_input/delta_z_bg[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Width of a height bin in each atmospheric histogram, Ha, if calculating Ha from the photon cloud. Surface-type dependent.
-
long_name:
Histogram height bin size for noise calculation from photon cloud
-
source:
ATL03, Section 5, _zBG
/ancillary_data/gt1l/signal_find_input/e_linfit_edit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of linear fit to signal photons used to edit out noise during running linear fit edit of outliers.
-
long_name:
Multiplier of STD of linear fit
-
source:
ATL03, Section 5, e_linfit_edit
-
units:
1
/ancillary_data/gt1l/signal_find_input/e_m[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of the number of background photon events per bin used in determining signal photon threshold. Surface-type dependent.
-
long_name:
Multiplier of STD of background
-
source:
ATL03, Section 5, em
-
units:
1
/ancillary_data/gt1l/signal_find_input/snrlow[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio below which all selected signal has low confidence.
-
long_name:
Signal to noise ratio low
-
source:
ATL03, Section 5, snrlow
-
units:
1
/ancillary_data/gt1l/signal_find_input/nslw_v[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half the value of the height window used for slant histogramming relative to the surface used when varying the surface slope, alpha, to fill large gaps. Surface-type dependent.
-
long_name:
Half height for variable slope slant histogramming
-
source:
ATL03, Section 5, nslw_v
-
units:
meters
/ancillary_data/gt1l/signal_find_input/nphot_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons over which to perform a linear fit to estimate the surface profile across a gap. Surface-type dependent.
-
long_name:
Minimum number of photons to fill gap
-
source:
ATL03, Section 5, Nphotmin
-
units:
counts
/ancillary_data/gt1l/signal_find_input/delta_zmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height bin size for histogramming for first sweep. Surface-type dependent.
-
long_name:
Minimum height bin size
-
source:
ATL03, Section 5, _zmin
-
units:
meters
/ancillary_data/gt1l/signal_find_input/delta_t_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Maximum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Maximum time
-
source:
ATL03, Section 5, _tmax
/ancillary_data/gt1l/signal_find_input/lslant_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform slant histogramming for the strong beam. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
Flag to request slant histogramming for strong beams.
-
source:
ATL03, Section 5, lslant
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt1l/signal_find_input/n_delta_z2[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmax1 and delta_zmax2. Surface-type dependent.
-
long_name:
number of increments in z2
-
source:
ATL03, Section 5, n_z2
-
units:
counts
/ancillary_data/gt1l/signal_find_input/e_m_mult[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of e_m used to determine Thsig2, threshold for singular bins. Surface-type dependent.
-
long_name:
Multiplier of STD of e_m
-
source:
ATL03, Section 5, em_mult
-
units:
1
/ancillary_data/gt1l/signal_find_input/delta_t_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Minimum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Minimum time
-
source:
ATL03, Section 5, _tmin
/ancillary_data/gt1l/signal_find_input/r2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of (maximum number of photons in any one bin of contiguous signal bins)/(Maximum number of photons in largest bin) in order to accept a group of potential signal bins as signal. Surface-type dependent.
-
long_name:
Minimum ratio2
-
source:
ATL03, Section 5, R2
-
units:
1
/ancillary_data/gt1l/signal_find_input/snrmed[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio above which all selected signal has high confidence. Selected signal with signal to noise ratio between snrlow and snrmed is marked as medium confidence.
-
long_name:
Signal to noise ratio medium
-
source:
ATL03, Section 5, snrmed
-
units:
1
/ancillary_data/gt1l/signal_find_input/n_delta_z1[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmin and delat_zmax1. Surface-type dependent.
-
long_name:
number of increments in z1
-
source:
ATL03, Section 5, n_z1
-
units:
counts
/ancillary_data/gt1l/signal_find_input/min_fit_time_fact[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The factor to multiply DTIME by to obtain the minimum time over which to fit a line to a height profile to calculate the local slope using running linear fits, min_fit_time.
-
long_name:
minimum fit time factor
-
source:
ATL03, Section 5, min_fit_time_fact
-
units:
seconds
/ancillary_data/gt1l/signal_find_input/pc_bckgrd_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then always use the photon cloud to calculate the background photon rate, if false only use the photon cloud in the absence of the atmospheric histogram. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
calculated background rate flag
-
source:
ATL03, Section 5, Lpcbg
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt1l/signal_find_input/t_gap_big[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
For time gaps less than this value, slant histogramming is performed relative to the linear slope calculated from the surrounding signal. For time gaps greater than or equal to this value the slope is varied when performing slant histogramming. Surface-type dependent.
-
long_name:
Gap size criteria
-
source:
ATL03, Section 5, tgapbig
-
units:
seconds
/ancillary_data/gt1l/signal_find_input/e_a[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of Ha_sigma used to determine which bins in the atmospheric histogram may contain signal photon events. Surface-type dependent.
-
long_name:
Multiplier of Ha_sigma
-
source:
ATL03, Section 5, ea
-
units:
1
/ancillary_data/gt1l/signal_find_input/delta_zmax2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
meters
-
description:
Maximum height bin size for histogramming for second sweep. Surface-type dependent.
-
long_name:
Maximum height bin size 2
-
source:
ATL03, Section 5, _zmax2
/ancillary_data/gt1l/signal_find_input/nslw[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half of the value of the height window used for slant histogramming relative to the surface defined by the linear fit to the surrounding photons at slope, alpha. Surface-type dependent.
-
long_name:
half height for slant histogramming
-
source:
ATL03, Section 5, nslw
-
units:
meters
/ancillary_data/gt1l/signal_find_input/e_linfit_slant[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of sigma_linfit, the standard deviation of the residuals between the actual photon events used to estimate the surface using a linear fit; all photons with height > e_linfit_slant
-
long_name:
Multiplier of sigma linfit
-
source:
ATL03, Section 5, e_linfit_slant
-
units:
1
/ancillary_data/gt1l/signal_find_input/addpad_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) that if true (=1) then identify additional photon events as padding to achieve htspanin for each time interval sig_find_t_inc.
-
long_name:
Additional photon flag
-
source:
ATL03, Section 5, Addpad
-
units:
1
/ancillary_data/gt1l/signal_find_input/nbin_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of bins in a histogram required for the algorithm to be able to process the histogram.
-
long_name:
Minimum number of bins
-
source:
ATL03, Section 5, Nbinmin
-
units:
counts
/ancillary_data/gt1l/signal_find_input/htspanmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height span for each time interval of photons with confidence flag > 0. If the height span is < htspanmin then all photons not previously selected within +/- htspanmin/2 of the median height of the signal photons selected are marked with a confidence flag of 1. Surface-type dependent.
-
long_name:
Minimum height span
-
source:
ATL03, Section 5, Htspanmin
-
units:
meters
/ancillary_data/gt1l/signal_find_input/alpha_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Increment by which the slope is varied for slant histogramming over large gaps
-
long_name:
Slope Increment
-
source:
ATL03, Section 5, _inc
-
units:
radians
/ancillary_data/gt1l/signal_find_input/out_edit_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform an n _ edit on a running linear fit to identified signal to remove outliers. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
outlier edit flag
-
source:
ATL03, Section 5, Ledit
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt1l/signal_find_input/delta_t_gap_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum size of a time gap in the height profile over which to use variable slope slant histogramming.
-
long_name:
Mimimum delta time gap
-
source:
ATL03, Section 5, _time_gapmin
-
units:
seconds
/ancillary_data/gt1l/signal_find_input/delta_t_lin_fit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time span over which to perform a running linear fit to identified signal photon events when editing outliers. Surface type dependent.
-
long_name:
Linear fit time increment
-
source:
ATL03, Section 5, _t_linfit_edit
-
units:
seconds
/ancillary_data/gt1l/signal_find_input/r[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of max number of photons in histogram bin to mean noise value that must exist to consider a bin a signal bin.
-
long_name:
Minimum ratio
-
source:
ATL03, Section 5, R
-
units:
1
/ancillary_data/altimetry/atl03_pad[
0
..0]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Seconds of padding data needed for ATL03 processing.
-
long_name:
Padding for ATL03 processing
-
source:
Control
-
units:
seconds
/ancillary_data/altimetry/min_full_sat[
0
..1]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons within a single transmit pulse that determines the pulse is fully saturated. (strong, weak)
-
long_name:
Min Full Saturation Photons
-
source:
Control
-
units:
1
/ancillary_data/altimetry/min_near_sat[
0
..1]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons within a single transmit pulse that determines the pulse is nearly saturated. (strong, weak)
-
long_name:
Min Near Saturation Photons
-
source:
Control
-
units:
1
/ancillary_data/altimetry/min_sat_h[
0
..0]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The height, in meters, used for determining a saturated transmit pulse.
-
long_name:
Minimum saturation height
-
source:
Control
-
units:
meters
/ancillary_data/altimetry/podppd_pad[
0
..0]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
source:
Control
-
description:
Seconds of padding data needed for POD/PPD interpolation.
-
long_name:
Padding for POD/PPD Interpolation
-
units:
seconds
/ancillary_data/altimetry/band_tol[
0
..0]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The tolerance, in meters, used to identify telemetry bands that do no intersect the DEM.
-
long_name:
Tolerance for band-to-DEM comparison
-
source:
Control
-
units:
meters
/ancillary_data/gt3l/signal_find_input/sig_find_t_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time increment the algorithm uses to step through the photon cloud in a granule. Histograms are formed at each sig_find_t_inc interval to identify signal photon events.
-
long_name:
Histogram time increment
-
source:
ATL03, Section 5, _time
-
units:
seconds
/ancillary_data/gt3l/signal_find_input/alpha_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Maximum slope allowed for slant histogram; if larger than this then don
-
long_name:
Maximum Slope
-
source:
ATL03, Section 5, _max
-
units:
radians
/ancillary_data/gt3l/signal_find_input/delta_z_bg[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Width of a height bin in each atmospheric histogram, Ha, if calculating Ha from the photon cloud. Surface-type dependent.
-
long_name:
Histogram height bin size for noise calculation from photon cloud
-
source:
ATL03, Section 5, _zBG
/ancillary_data/gt3l/signal_find_input/e_linfit_edit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of linear fit to signal photons used to edit out noise during running linear fit edit of outliers.
-
long_name:
Multiplier of STD of linear fit
-
source:
ATL03, Section 5, e_linfit_edit
-
units:
1
/ancillary_data/gt3l/signal_find_input/e_m[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of the number of background photon events per bin used in determining signal photon threshold. Surface-type dependent.
-
long_name:
Multiplier of STD of background
-
source:
ATL03, Section 5, em
-
units:
1
/ancillary_data/gt3l/signal_find_input/snrlow[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio below which all selected signal has low confidence.
-
long_name:
Signal to noise ratio low
-
source:
ATL03, Section 5, snrlow
-
units:
1
/ancillary_data/gt3l/signal_find_input/nslw_v[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half the value of the height window used for slant histogramming relative to the surface used when varying the surface slope, alpha, to fill large gaps. Surface-type dependent.
-
long_name:
Half height for variable slope slant histogramming
-
source:
ATL03, Section 5, nslw_v
-
units:
meters
/ancillary_data/gt3l/signal_find_input/nphot_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons over which to perform a linear fit to estimate the surface profile across a gap. Surface-type dependent.
-
long_name:
Minimum number of photons to fill gap
-
source:
ATL03, Section 5, Nphotmin
-
units:
counts
/ancillary_data/gt3l/signal_find_input/delta_zmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height bin size for histogramming for first sweep. Surface-type dependent.
-
long_name:
Minimum height bin size
-
source:
ATL03, Section 5, _zmin
-
units:
meters
/ancillary_data/gt3l/signal_find_input/delta_t_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Maximum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Maximum time
-
source:
ATL03, Section 5, _tmax
/ancillary_data/gt3l/signal_find_input/lslant_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform slant histogramming for the strong beam. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
Flag to request slant histogramming for strong beams.
-
source:
ATL03, Section 5, lslant
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt3l/signal_find_input/n_delta_z2[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmax1 and delta_zmax2. Surface-type dependent.
-
long_name:
number of increments in z2
-
source:
ATL03, Section 5, n_z2
-
units:
counts
/ancillary_data/gt3l/signal_find_input/e_m_mult[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of e_m used to determine Thsig2, threshold for singular bins. Surface-type dependent.
-
long_name:
Multiplier of STD of e_m
-
source:
ATL03, Section 5, em_mult
-
units:
1
/ancillary_data/gt3l/signal_find_input/delta_t_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Minimum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Minimum time
-
source:
ATL03, Section 5, _tmin
/ancillary_data/gt3l/signal_find_input/r2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of (maximum number of photons in any one bin of contiguous signal bins)/(Maximum number of photons in largest bin) in order to accept a group of potential signal bins as signal. Surface-type dependent.
-
long_name:
Minimum ratio2
-
source:
ATL03, Section 5, R2
-
units:
1
/ancillary_data/gt3l/signal_find_input/snrmed[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio above which all selected signal has high confidence. Selected signal with signal to noise ratio between snrlow and snrmed is marked as medium confidence.
-
long_name:
Signal to noise ratio medium
-
source:
ATL03, Section 5, snrmed
-
units:
1
/ancillary_data/gt3l/signal_find_input/n_delta_z1[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmin and delat_zmax1. Surface-type dependent.
-
long_name:
number of increments in z1
-
source:
ATL03, Section 5, n_z1
-
units:
counts
/ancillary_data/gt3l/signal_find_input/min_fit_time_fact[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The factor to multiply DTIME by to obtain the minimum time over which to fit a line to a height profile to calculate the local slope using running linear fits, min_fit_time.
-
long_name:
minimum fit time factor
-
source:
ATL03, Section 5, min_fit_time_fact
-
units:
seconds
/ancillary_data/gt3l/signal_find_input/pc_bckgrd_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then always use the photon cloud to calculate the background photon rate, if false only use the photon cloud in the absence of the atmospheric histogram. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
calculated background rate flag
-
source:
ATL03, Section 5, Lpcbg
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt3l/signal_find_input/t_gap_big[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
For time gaps less than this value, slant histogramming is performed relative to the linear slope calculated from the surrounding signal. For time gaps greater than or equal to this value the slope is varied when performing slant histogramming. Surface-type dependent.
-
long_name:
Gap size criteria
-
source:
ATL03, Section 5, tgapbig
-
units:
seconds
/ancillary_data/gt3l/signal_find_input/e_a[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of Ha_sigma used to determine which bins in the atmospheric histogram may contain signal photon events. Surface-type dependent.
-
long_name:
Multiplier of Ha_sigma
-
source:
ATL03, Section 5, ea
-
units:
1
/ancillary_data/gt3l/signal_find_input/delta_zmax2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
meters
-
description:
Maximum height bin size for histogramming for second sweep. Surface-type dependent.
-
long_name:
Maximum height bin size 2
-
source:
ATL03, Section 5, _zmax2
/ancillary_data/gt3l/signal_find_input/nslw[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half of the value of the height window used for slant histogramming relative to the surface defined by the linear fit to the surrounding photons at slope, alpha. Surface-type dependent.
-
long_name:
half height for slant histogramming
-
source:
ATL03, Section 5, nslw
-
units:
meters
/ancillary_data/gt3l/signal_find_input/e_linfit_slant[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of sigma_linfit, the standard deviation of the residuals between the actual photon events used to estimate the surface using a linear fit; all photons with height > e_linfit_slant
-
long_name:
Multiplier of sigma linfit
-
source:
ATL03, Section 5, e_linfit_slant
-
units:
1
/ancillary_data/gt3l/signal_find_input/addpad_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) that if true (=1) then identify additional photon events as padding to achieve htspanin for each time interval sig_find_t_inc.
-
long_name:
Additional photon flag
-
source:
ATL03, Section 5, Addpad
-
units:
1
/ancillary_data/gt3l/signal_find_input/nbin_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of bins in a histogram required for the algorithm to be able to process the histogram.
-
long_name:
Minimum number of bins
-
source:
ATL03, Section 5, Nbinmin
-
units:
counts
/ancillary_data/gt3l/signal_find_input/htspanmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height span for each time interval of photons with confidence flag > 0. If the height span is < htspanmin then all photons not previously selected within +/- htspanmin/2 of the median height of the signal photons selected are marked with a confidence flag of 1. Surface-type dependent.
-
long_name:
Minimum height span
-
source:
ATL03, Section 5, Htspanmin
-
units:
meters
/ancillary_data/gt3l/signal_find_input/alpha_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Increment by which the slope is varied for slant histogramming over large gaps
-
long_name:
Slope Increment
-
source:
ATL03, Section 5, _inc
-
units:
radians
/ancillary_data/gt3l/signal_find_input/out_edit_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform an n _ edit on a running linear fit to identified signal to remove outliers. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
outlier edit flag
-
source:
ATL03, Section 5, Ledit
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt3l/signal_find_input/delta_t_gap_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum size of a time gap in the height profile over which to use variable slope slant histogramming.
-
long_name:
Mimimum delta time gap
-
source:
ATL03, Section 5, _time_gapmin
-
units:
seconds
/ancillary_data/gt3l/signal_find_input/delta_t_lin_fit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time span over which to perform a running linear fit to identified signal photon events when editing outliers. Surface type dependent.
-
long_name:
Linear fit time increment
-
source:
ATL03, Section 5, _t_linfit_edit
-
units:
seconds
/ancillary_data/gt3l/signal_find_input/r[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of max number of photons in histogram bin to mean noise value that must exist to consider a bin a signal bin.
-
long_name:
Minimum ratio
-
source:
ATL03, Section 5, R
-
units:
1
/ancillary_data/gt2l/signal_find_input/sig_find_t_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time increment the algorithm uses to step through the photon cloud in a granule. Histograms are formed at each sig_find_t_inc interval to identify signal photon events.
-
long_name:
Histogram time increment
-
source:
ATL03, Section 5, _time
-
units:
seconds
/ancillary_data/gt2l/signal_find_input/alpha_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Maximum slope allowed for slant histogram; if larger than this then don
-
long_name:
Maximum Slope
-
source:
ATL03, Section 5, _max
-
units:
radians
/ancillary_data/gt2l/signal_find_input/delta_z_bg[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Width of a height bin in each atmospheric histogram, Ha, if calculating Ha from the photon cloud. Surface-type dependent.
-
long_name:
Histogram height bin size for noise calculation from photon cloud
-
source:
ATL03, Section 5, _zBG
/ancillary_data/gt2l/signal_find_input/e_linfit_edit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of linear fit to signal photons used to edit out noise during running linear fit edit of outliers.
-
long_name:
Multiplier of STD of linear fit
-
source:
ATL03, Section 5, e_linfit_edit
-
units:
1
/ancillary_data/gt2l/signal_find_input/e_m[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of the number of background photon events per bin used in determining signal photon threshold. Surface-type dependent.
-
long_name:
Multiplier of STD of background
-
source:
ATL03, Section 5, em
-
units:
1
/ancillary_data/gt2l/signal_find_input/snrlow[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio below which all selected signal has low confidence.
-
long_name:
Signal to noise ratio low
-
source:
ATL03, Section 5, snrlow
-
units:
1
/ancillary_data/gt2l/signal_find_input/nslw_v[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half the value of the height window used for slant histogramming relative to the surface used when varying the surface slope, alpha, to fill large gaps. Surface-type dependent.
-
long_name:
Half height for variable slope slant histogramming
-
source:
ATL03, Section 5, nslw_v
-
units:
meters
/ancillary_data/gt2l/signal_find_input/nphot_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons over which to perform a linear fit to estimate the surface profile across a gap. Surface-type dependent.
-
long_name:
Minimum number of photons to fill gap
-
source:
ATL03, Section 5, Nphotmin
-
units:
counts
/ancillary_data/gt2l/signal_find_input/delta_zmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height bin size for histogramming for first sweep. Surface-type dependent.
-
long_name:
Minimum height bin size
-
source:
ATL03, Section 5, _zmin
-
units:
meters
/ancillary_data/gt2l/signal_find_input/delta_t_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Maximum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Maximum time
-
source:
ATL03, Section 5, _tmax
/ancillary_data/gt2l/signal_find_input/lslant_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform slant histogramming for the strong beam. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
Flag to request slant histogramming for strong beams.
-
source:
ATL03, Section 5, lslant
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt2l/signal_find_input/n_delta_z2[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmax1 and delta_zmax2. Surface-type dependent.
-
long_name:
number of increments in z2
-
source:
ATL03, Section 5, n_z2
-
units:
counts
/ancillary_data/gt2l/signal_find_input/e_m_mult[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of e_m used to determine Thsig2, threshold for singular bins. Surface-type dependent.
-
long_name:
Multiplier of STD of e_m
-
source:
ATL03, Section 5, em_mult
-
units:
1
/ancillary_data/gt2l/signal_find_input/delta_t_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Minimum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Minimum time
-
source:
ATL03, Section 5, _tmin
/ancillary_data/gt2l/signal_find_input/r2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of (maximum number of photons in any one bin of contiguous signal bins)/(Maximum number of photons in largest bin) in order to accept a group of potential signal bins as signal. Surface-type dependent.
-
long_name:
Minimum ratio2
-
source:
ATL03, Section 5, R2
-
units:
1
/ancillary_data/gt2l/signal_find_input/snrmed[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio above which all selected signal has high confidence. Selected signal with signal to noise ratio between snrlow and snrmed is marked as medium confidence.
-
long_name:
Signal to noise ratio medium
-
source:
ATL03, Section 5, snrmed
-
units:
1
/ancillary_data/gt2l/signal_find_input/n_delta_z1[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmin and delat_zmax1. Surface-type dependent.
-
long_name:
number of increments in z1
-
source:
ATL03, Section 5, n_z1
-
units:
counts
/ancillary_data/gt2l/signal_find_input/min_fit_time_fact[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The factor to multiply DTIME by to obtain the minimum time over which to fit a line to a height profile to calculate the local slope using running linear fits, min_fit_time.
-
long_name:
minimum fit time factor
-
source:
ATL03, Section 5, min_fit_time_fact
-
units:
seconds
/ancillary_data/gt2l/signal_find_input/pc_bckgrd_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then always use the photon cloud to calculate the background photon rate, if false only use the photon cloud in the absence of the atmospheric histogram. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
calculated background rate flag
-
source:
ATL03, Section 5, Lpcbg
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt2l/signal_find_input/t_gap_big[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
For time gaps less than this value, slant histogramming is performed relative to the linear slope calculated from the surrounding signal. For time gaps greater than or equal to this value the slope is varied when performing slant histogramming. Surface-type dependent.
-
long_name:
Gap size criteria
-
source:
ATL03, Section 5, tgapbig
-
units:
seconds
/ancillary_data/gt2l/signal_find_input/e_a[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of Ha_sigma used to determine which bins in the atmospheric histogram may contain signal photon events. Surface-type dependent.
-
long_name:
Multiplier of Ha_sigma
-
source:
ATL03, Section 5, ea
-
units:
1
/ancillary_data/gt2l/signal_find_input/delta_zmax2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
meters
-
description:
Maximum height bin size for histogramming for second sweep. Surface-type dependent.
-
long_name:
Maximum height bin size 2
-
source:
ATL03, Section 5, _zmax2
/ancillary_data/gt2l/signal_find_input/nslw[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half of the value of the height window used for slant histogramming relative to the surface defined by the linear fit to the surrounding photons at slope, alpha. Surface-type dependent.
-
long_name:
half height for slant histogramming
-
source:
ATL03, Section 5, nslw
-
units:
meters
/ancillary_data/gt2l/signal_find_input/e_linfit_slant[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of sigma_linfit, the standard deviation of the residuals between the actual photon events used to estimate the surface using a linear fit; all photons with height > e_linfit_slant
-
long_name:
Multiplier of sigma linfit
-
source:
ATL03, Section 5, e_linfit_slant
-
units:
1
/ancillary_data/gt2l/signal_find_input/addpad_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) that if true (=1) then identify additional photon events as padding to achieve htspanin for each time interval sig_find_t_inc.
-
long_name:
Additional photon flag
-
source:
ATL03, Section 5, Addpad
-
units:
1
/ancillary_data/gt2l/signal_find_input/nbin_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of bins in a histogram required for the algorithm to be able to process the histogram.
-
long_name:
Minimum number of bins
-
source:
ATL03, Section 5, Nbinmin
-
units:
counts
/ancillary_data/gt2l/signal_find_input/htspanmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height span for each time interval of photons with confidence flag > 0. If the height span is < htspanmin then all photons not previously selected within +/- htspanmin/2 of the median height of the signal photons selected are marked with a confidence flag of 1. Surface-type dependent.
-
long_name:
Minimum height span
-
source:
ATL03, Section 5, Htspanmin
-
units:
meters
/ancillary_data/gt2l/signal_find_input/alpha_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Increment by which the slope is varied for slant histogramming over large gaps
-
long_name:
Slope Increment
-
source:
ATL03, Section 5, _inc
-
units:
radians
/ancillary_data/gt2l/signal_find_input/out_edit_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform an n _ edit on a running linear fit to identified signal to remove outliers. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
outlier edit flag
-
source:
ATL03, Section 5, Ledit
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt2l/signal_find_input/delta_t_gap_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum size of a time gap in the height profile over which to use variable slope slant histogramming.
-
long_name:
Mimimum delta time gap
-
source:
ATL03, Section 5, _time_gapmin
-
units:
seconds
/ancillary_data/gt2l/signal_find_input/delta_t_lin_fit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time span over which to perform a running linear fit to identified signal photon events when editing outliers. Surface type dependent.
-
long_name:
Linear fit time increment
-
source:
ATL03, Section 5, _t_linfit_edit
-
units:
seconds
/ancillary_data/gt2l/signal_find_input/r[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of max number of photons in histogram bin to mean noise value that must exist to consider a bin a signal bin.
-
long_name:
Minimum ratio
-
source:
ATL03, Section 5, R
-
units:
1
/ancillary_data/tep/tep_normalize[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Indicates if the TEP histogram was normalized. 0=not normalized; 1=normalized
-
flag_meanings:
not_normalized normalized
-
flag_values:
0, 1
-
long_name:
Normalization Enabled
-
source:
Ops
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/tep/tep_valid_spot[
0
..5]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
description:
A 6x1 array indicating which TEP to use for each spot that does not have a TEP associated with it (e.g. which TEP to use to characterize spots 2, 4, 5, and 6).
-
flag_meanings:
pce1_spot1 pce2_spot3
-
flag_values:
1, 2
-
long_name:
Index of TEP Spot
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
2
-
valid_min:
1
/ancillary_data/tep/tep_range_prim[
0
..1]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The range of time of flight of TEP photon events to include in generating a histogram or other analaysis of the primary TEP return
-
long_name:
Range of Primary TEP Window
-
source:
ATL03 ATBD
-
units:
seconds
/ancillary_data/tep/tep_start_x[
0
..0]
(Type is Float32)
/ancillary_data/tep/min_tep_secs[
0
..0]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum seconds of data required for computing a TEP histogram.
-
long_name:
Minimum TEP Seconds
-
source:
Derived
-
units:
seconds
/ancillary_data/tep/tep_sec_window[
0
..1]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The range of the secondary TEP window. Bins within this range are used in computing TEP rate.
-
long_name:
TEP Secondary Window
-
source:
Derived
-
units:
seconds
/ancillary_data/tep/tep_rm_noise[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Indicates if noise was removed from the TEP histogram. 0=background noise not removed; 1=background noise removed
-
flag_meanings:
noise_not_removed noise_removed
-
flag_values:
0, 1
-
long_name:
Noise Removal Enabled
-
source:
Ops
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/tep/tep_bin_size[
0
..0]
(Type is Float32)
/ancillary_data/tep/n_tep_bins[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Number of bins in each TEP histogram
-
long_name:
Number of Bins
-
source:
Derived
-
units:
counts
/ancillary_data/tep/ds_gt[
ds_gt=
0
..5]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
description:
Dimension scale for ATLAS Groundtracks (gt1l, gt1r, gt2l, gt2r, gt3l, gt3r)
-
flag_meanings:
gt1l gt1r gt2l gt2r gt3l gt3r
-
flag_values:
1, 2, 3, 4, 5, 6
-
long_name:
GT Index
-
units:
1
-
valid_max:
6
-
valid_min:
1
/ancillary_data/tep/min_tep_ph[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of TEP photons required for computing a TEP histogram.
-
long_name:
Minimum TEP photons
-
source:
Derived
-
units:
seconds
/ancillary_data/tep/tep_peak_bins[
0
..0]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Number of peak bins to remove for TEP background computation.
-
long_name:
Number of Peak Bins to Remove
-
source:
Derived
-
units:
counts
/ancillary_data/tep/tep_gap_size[
0
..0]
(Type is Float64)
/ancillary_data/tep/tep_prim_window[
0
..1]
(Type is Float32)
-
attributes
-
contentType:
auxiliaryInformation
-
source:
Derived
-
description:
The range of the primary TEP window. Bins within this range are used in computing TEP rate.
-
long_name:
TEP Primary Window
-
units:
seconds
/ancillary_data/gt3r/signal_find_input/sig_find_t_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time increment the algorithm uses to step through the photon cloud in a granule. Histograms are formed at each sig_find_t_inc interval to identify signal photon events.
-
long_name:
Histogram time increment
-
source:
ATL03, Section 5, _time
-
units:
seconds
/ancillary_data/gt3r/signal_find_input/alpha_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Maximum slope allowed for slant histogram; if larger than this then don
-
long_name:
Maximum Slope
-
source:
ATL03, Section 5, _max
-
units:
radians
/ancillary_data/gt3r/signal_find_input/delta_z_bg[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Width of a height bin in each atmospheric histogram, Ha, if calculating Ha from the photon cloud. Surface-type dependent.
-
long_name:
Histogram height bin size for noise calculation from photon cloud
-
source:
ATL03, Section 5, _zBG
/ancillary_data/gt3r/signal_find_input/e_linfit_edit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of linear fit to signal photons used to edit out noise during running linear fit edit of outliers.
-
long_name:
Multiplier of STD of linear fit
-
source:
ATL03, Section 5, e_linfit_edit
-
units:
1
/ancillary_data/gt3r/signal_find_input/e_m[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of standard deviation of the number of background photon events per bin used in determining signal photon threshold. Surface-type dependent.
-
long_name:
Multiplier of STD of background
-
source:
ATL03, Section 5, em
-
units:
1
/ancillary_data/gt3r/signal_find_input/snrlow[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio below which all selected signal has low confidence.
-
long_name:
Signal to noise ratio low
-
source:
ATL03, Section 5, snrlow
-
units:
1
/ancillary_data/gt3r/signal_find_input/nslw_v[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half the value of the height window used for slant histogramming relative to the surface used when varying the surface slope, alpha, to fill large gaps. Surface-type dependent.
-
long_name:
Half height for variable slope slant histogramming
-
source:
ATL03, Section 5, nslw_v
-
units:
meters
/ancillary_data/gt3r/signal_find_input/nphot_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The minimum number of photons over which to perform a linear fit to estimate the surface profile across a gap. Surface-type dependent.
-
long_name:
Minimum number of photons to fill gap
-
source:
ATL03, Section 5, Nphotmin
-
units:
counts
/ancillary_data/gt3r/signal_find_input/delta_zmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height bin size for histogramming for first sweep. Surface-type dependent.
-
long_name:
Minimum height bin size
-
source:
ATL03, Section 5, _zmin
-
units:
meters
/ancillary_data/gt3r/signal_find_input/delta_t_max[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Maximum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Maximum time
-
source:
ATL03, Section 5, _tmax
/ancillary_data/gt3r/signal_find_input/lslant_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform slant histogramming for the strong beam. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
Flag to request slant histogramming for strong beams.
-
source:
ATL03, Section 5, lslant
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt3r/signal_find_input/n_delta_z2[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmax1 and delta_zmax2. Surface-type dependent.
-
long_name:
number of increments in z2
-
source:
ATL03, Section 5, n_z2
-
units:
counts
/ancillary_data/gt3r/signal_find_input/e_m_mult[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of e_m used to determine Thsig2, threshold for singular bins. Surface-type dependent.
-
long_name:
Multiplier of STD of e_m
-
source:
ATL03, Section 5, em_mult
-
units:
1
/ancillary_data/gt3r/signal_find_input/delta_t_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
seconds
-
description:
Minimum time interval over which photons are selected to histogram. Surface-type dependent.
-
long_name:
Histogram Minimum time
-
source:
ATL03, Section 5, _tmin
/ancillary_data/gt3r/signal_find_input/r2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of (maximum number of photons in any one bin of contiguous signal bins)/(Maximum number of photons in largest bin) in order to accept a group of potential signal bins as signal. Surface-type dependent.
-
long_name:
Minimum ratio2
-
source:
ATL03, Section 5, R2
-
units:
1
/ancillary_data/gt3r/signal_find_input/snrmed[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Signal to noise ratio above which all selected signal has high confidence. Selected signal with signal to noise ratio between snrlow and snrmed is marked as medium confidence.
-
long_name:
Signal to noise ratio medium
-
source:
ATL03, Section 5, snrmed
-
units:
1
/ancillary_data/gt3r/signal_find_input/n_delta_z1[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The number of increments between delta_zmin and delat_zmax1. Surface-type dependent.
-
long_name:
number of increments in z1
-
source:
ATL03, Section 5, n_z1
-
units:
counts
/ancillary_data/gt3r/signal_find_input/min_fit_time_fact[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
The factor to multiply DTIME by to obtain the minimum time over which to fit a line to a height profile to calculate the local slope using running linear fits, min_fit_time.
-
long_name:
minimum fit time factor
-
source:
ATL03, Section 5, min_fit_time_fact
-
units:
seconds
/ancillary_data/gt3r/signal_find_input/pc_bckgrd_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then always use the photon cloud to calculate the background photon rate, if false only use the photon cloud in the absence of the atmospheric histogram. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
calculated background rate flag
-
source:
ATL03, Section 5, Lpcbg
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt3r/signal_find_input/t_gap_big[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
For time gaps less than this value, slant histogramming is performed relative to the linear slope calculated from the surrounding signal. For time gaps greater than or equal to this value the slope is varied when performing slant histogramming. Surface-type dependent.
-
long_name:
Gap size criteria
-
source:
ATL03, Section 5, tgapbig
-
units:
seconds
/ancillary_data/gt3r/signal_find_input/e_a[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of Ha_sigma used to determine which bins in the atmospheric histogram may contain signal photon events. Surface-type dependent.
-
long_name:
Multiplier of Ha_sigma
-
source:
ATL03, Section 5, ea
-
units:
1
/ancillary_data/gt3r/signal_find_input/delta_zmax2[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
units:
meters
-
description:
Maximum height bin size for histogramming for second sweep. Surface-type dependent.
-
long_name:
Maximum height bin size 2
-
source:
ATL03, Section 5, _zmax2
/ancillary_data/gt3r/signal_find_input/nslw[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Half of the value of the height window used for slant histogramming relative to the surface defined by the linear fit to the surrounding photons at slope, alpha. Surface-type dependent.
-
long_name:
half height for slant histogramming
-
source:
ATL03, Section 5, nslw
-
units:
meters
/ancillary_data/gt3r/signal_find_input/e_linfit_slant[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Multiplier of sigma_linfit, the standard deviation of the residuals between the actual photon events used to estimate the surface using a linear fit; all photons with height > e_linfit_slant
-
long_name:
Multiplier of sigma linfit
-
source:
ATL03, Section 5, e_linfit_slant
-
units:
1
/ancillary_data/gt3r/signal_find_input/addpad_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) that if true (=1) then identify additional photon events as padding to achieve htspanin for each time interval sig_find_t_inc.
-
long_name:
Additional photon flag
-
source:
ATL03, Section 5, Addpad
-
units:
1
/ancillary_data/gt3r/signal_find_input/nbin_min[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum number of bins in a histogram required for the algorithm to be able to process the histogram.
-
long_name:
Minimum number of bins
-
source:
ATL03, Section 5, Nbinmin
-
units:
counts
/ancillary_data/gt3r/signal_find_input/htspanmin[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum height span for each time interval of photons with confidence flag > 0. If the height span is < htspanmin then all photons not previously selected within +/- htspanmin/2 of the median height of the signal photons selected are marked with a confidence flag of 1. Surface-type dependent.
-
long_name:
Minimum height span
-
source:
ATL03, Section 5, Htspanmin
-
units:
meters
/ancillary_data/gt3r/signal_find_input/alpha_inc[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Increment by which the slope is varied for slant histogramming over large gaps
-
long_name:
Slope Increment
-
source:
ATL03, Section 5, _inc
-
units:
radians
/ancillary_data/gt3r/signal_find_input/out_edit_flag[
0
..4]
(Type is Int32)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Binary (logical) flag, if true (=1) then perform an n _ edit on a running linear fit to identified signal to remove outliers. Surface-type dependent.
-
flag_meanings:
false true
-
flag_values:
0, 1
-
long_name:
outlier edit flag
-
source:
ATL03, Section 5, Ledit
-
units:
1
-
valid_max:
1
-
valid_min:
0
/ancillary_data/gt3r/signal_find_input/delta_t_gap_min[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum size of a time gap in the height profile over which to use variable slope slant histogramming.
-
long_name:
Mimimum delta time gap
-
source:
ATL03, Section 5, _time_gapmin
-
units:
seconds
/ancillary_data/gt3r/signal_find_input/delta_t_lin_fit[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Time span over which to perform a running linear fit to identified signal photon events when editing outliers. Surface type dependent.
-
long_name:
Linear fit time increment
-
source:
ATL03, Section 5, _t_linfit_edit
-
units:
seconds
/ancillary_data/gt3r/signal_find_input/r[
0
..4]
(Type is Float64)
-
attributes
-
contentType:
auxiliaryInformation
-
description:
Minimum ratio of max number of photons in histogram bin to mean noise value that must exist to consider a bin a signal bin.
-
long_name:
Minimum ratio
-
source:
ATL03, Section 5, R
-
units:
1
/gt3r/bckgrd_atlas/bckgrd_int_height[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the altimetric range window. This is the height over which the 50-shot sum is generated. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Altimetric range window width
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt3r/bckgrd_atlas/tlm_height_band1[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
long_name:
Height of the telemetry band 1
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
-
description:
The height in meters of the telemetry band 1.
/gt3r/bckgrd_atlas/bckgrd_rate[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The background count rate from the 50-shot altimetric histogram after removing the number of likely signal photons based on Section 5.
-
long_name:
Background count rate based on the ATLAS 50-shot sum
-
source:
ATL03 ATBD Section 7.3
-
units:
counts / second
/gt3r/bckgrd_atlas/tlm_top_band1[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 1, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 1.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt3r/bckgrd_atlas/tlm_top_band2[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The ellipsoidal heights with respect to WGS-84 of the top of the telemetry band 2, with all geophysical corrections applied.
-
long_name:
Ellipsoidal height of the top of the telemetry band 2.
-
source:
ATL03 ATBD, Section 3.2, 7.3.2
-
units:
meters
/gt3r/bckgrd_atlas/bckgrd_int_height_reduced[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
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:
Altimetric range window height - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt3r/bckgrd_atlas/bckgrd_hist_top[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
The height of the top of the altimetric histogram, in meters above the WGS-84 ellipsoid, with all geophysical corrections applied. Parameter is ingested at 50-Hz, and values are repeated to form a 200-Hz array.
-
long_name:
Top of the altimetric range window
-
source:
ATL03 ATBD Section 7.3
-
units:
meters
/gt3r/bckgrd_atlas/bckgrd_counts_reduced[
delta_time=
0
..91170]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Number of photon counts in the 50-shot sum after subtracting the number of signal photon events, defined as in ATBD Section 5, in that span.
-
long_name:
ATLAS 50-shot background count - reduced
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt3r/bckgrd_atlas/tlm_height_band2[
delta_time=
0
..91170]
(Type is Float32)
-
attributes
-
coordinates:
delta_time
-
description:
The height in meters of the telemetry band 2. (if 0, second band is not present).
-
long_name:
Height of the telemetry band 2
-
source:
ATL03 ATBD, Section 7.3.2
-
units:
meters
/gt3r/bckgrd_atlas/delta_time[
delta_time=
0
..91170]
(Type is Float64)
-
attributes
-
description:
Elapsed GPS Seconds from the ATLAS SDP GPS Epoch, referenced to the start of the 50-shot sum. This is based on every fiftieth laser fire time, which leads to a very close alignment with major frame boundaries (+/- 1 shot). 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 at the start of ATLAS 50-shot sum
-
source:
ATL02
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/bckgrd_atlas/bckgrd_counts[
delta_time=
0
..91170]
(Type is Int32)
-
attributes
-
contentType:
modelResult
-
coordinates:
delta_time
-
description:
Onboard 50 shot background (200 Hz) sum of photon events within the altimetric range window.
-
long_name:
ATLAS 50-shot background count
-
source:
ATL03 ATBD Section 7.3
-
units:
counts
/gt3r/geolocation/segment_ph_cnt[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Number of photons in a given along-track segment. In the case of no photons within the segment (segment_ph_cnt=0), most other parameters are filled with invalid or best-estimate values. Maintaining geolocation segments with no photons allows for the geolocation segment arrays to be directly aligned across the gtx groups.
-
long_name:
Number of photons
-
source:
Derived
-
units:
counts
/gt3r/geolocation/segment_length[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The along-track length of the along-track segment. Nominally these are 20m, but they vary from 19.8m to 20.2m.
-
long_name:
along-track segment length
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt3r/geolocation/range_bias_corr[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The range_bias estimated from geolocation analysis.
-
long_name:
range bias correction
-
source:
ATL03G ATBD, Section 3.6
-
units:
meters
/gt3r/geolocation/neutat_delay_derivative[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Change in neutral atmospheric delay per height change
-
long_name:
(Neutral Atmosphere delay)/dh
-
source:
ATL03a ATBD
-
units:
meters/meters
/gt3r/geolocation/reference_photon_lon[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Longitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Longitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt3r/geolocation/sigma_across[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated Cartesian across-track uncertainity (1-sigma) for the refrerence photon
-
long_name:
across-track geolocation uncertainty
-
source:
ATL03G ATBD
-
units:
meters
/gt3r/geolocation/sigma_lon[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic east Longitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
longitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
degrees
/gt3r/geolocation/ref_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Azimuth of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from North and positive towards East.
-
long_name:
Azimuth
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
azimuth
-
units:
radians
/gt3r/geolocation/ref_elev[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Elevation of the unit pointing vector for the reference photon in the local ENU frame in radians. The angle is measured from East-North plane and positive towards Up
-
long_name:
elevation
-
source:
ATL03G ATBD, Section 3.3
-
standard_name:
elevation
-
units:
radians
/gt3r/geolocation/neutat_ht[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Reference height of the neutral atmosphere range correction
-
long_name:
Neutral atmosphere ref height
-
source:
ATL03a ATBD
-
units:
meters
/gt3r/geolocation/solar_azimuth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The azimuth of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from North and is positive towards East. ATL03g provides this value in radians; it is converted to degrees for ATL03 output.
-
long_name:
solar azimuth
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees_east
/gt3r/geolocation/surf_type[
delta_time=
0
..163492]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Flags describing which surface types this interval is associated with. 0=not type, 1=is type. Order of array is land, ocean, sea ice, land ice, inland water.
-
flag_meanings:
not_type is_type
-
flag_values:
0, 1
-
long_name:
Surface Type
-
source:
ATL03 ATBD, Section 4
-
units:
1
-
valid_max:
1
-
valid_min:
0
/gt3r/geolocation/sigma_lat[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated geodetic Latitude uncertainty (1-sigma), for the reference photon bounce point.
-
long_name:
latitude uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt3r/geolocation/tx_pulse_width_lower[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the lower threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Lower Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt3r/geolocation/sigma_along[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated cartesian along-track uncertainanty (1-sigma) for the reference photon
-
long_name:
along-track geolocation uncertainity
-
source:
ATL03G ATBD
-
units:
meters
/gt3r/geolocation/tx_pulse_skew_est[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the averages of the lower and upper threshold crossing times. This is an estimate of the transmit pulse skew.
-
long_name:
Transmit Pulse Skew Estimate
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt3r/geolocation/tx_pulse_energy[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
physicalMeasurement
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average transmit pulse energy, measured by the internal laser energy monitor, split into per-beam measurements.
-
long_name:
Transmit Pulse Energy
-
source:
ATL02 ATBD, Section 7.2
-
units:
Joules
/gt3r/geolocation/tx_pulse_width_upper[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The average distance between the upper threshold crossing times measured by the Start Pulse Detector.
-
long_name:
Transmit Pulse Energy Upper Width
-
source:
ATL02 ATBD, Section 7.2
-
units:
seconds
/gt3r/geolocation/sigma_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Estimated height uncertainty (1-sigma) for the reference photon bounce point.
-
long_name:
height uncertainty
-
source:
ATL03G ATBD, Section 3.6
-
units:
1
/gt3r/geolocation/podppd_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
0
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Composite POD/PPD flag that indicates the quality of input geolocation products for the specific ATL03 segment. A non-zero value may indicate that geolocation solutions are degraded. The ATL03 sigma values should indicate the degree of uncertainty associated with the degradation. Possible values are: 0=NOMINAL; 1=POD_DEGRADE; 2=PPD_DEGRADE; 3=PODPPD_DEGRADE.
-
flag_meanings:
nominal pod_degrade ppd_degrade podppd_degrade
-
flag_values:
0, 1, 2, 3
-
long_name:
POD_PPD Flag
-
source:
ANC04, ANC05
-
units:
1
-
valid_max:
3
-
valid_min:
0
/gt3r/geolocation/velocity_sc[
delta_time=
0
..163492]
[
ds_xyz=
0
..2]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Spacecraft velocity components (east component, north component, up component) an observer on the ground would measure. While values are common to all beams, this parameter is naturally produced as part of geolocation.
-
long_name:
spacecraft velocity
-
source:
ATL03G ATBD
-
units:
meters/second
/gt3r/geolocation/full_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be fully saturated.
-
long_name:
Full Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt3r/geolocation/segment_id[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
A 7 digit number identifiying the along-track geolocation segment number. These are sequential, starting with 1 for the first segment after an ascending equatorial crossing node.
-
long_name:
along-track segment ID number.
-
source:
ATL03 ATBD, Section 3.1
-
units:
1
/gt3r/geolocation/near_sat_fract[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
qualityInformation
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The fraction of pulses within the segment determined to be nearly saturated.
-
long_name:
Near Saturation Fraction
-
source:
ATL03 ATBD
-
units:
1
-
valid_max:
1.
-
valid_min:
0.
/gt3r/geolocation/reference_photon_lat[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time
-
description:
Latitude of each reference photon. Computed from the ECF Cartesian coordinates of the bounce point. In the case of no photons within the segment (segment_ph_cnt=0), the coordinates are the midpoint of the geolocation segment on the reference ground track.
-
long_name:
Segment Latitude
-
source:
ATL03G ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt3r/geolocation/solar_elevation[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The elevation of the sun position vector from the reference photon bounce point position in the local ENU frame. The angle is measured from the East-North plane and is positive Up. ATL03g provides this value in radians; it is converted to degress for ATL03 output.
-
long_name:
solar elevation
-
source:
ATL03G ATBD, Section 3.3
-
units:
degrees
/gt3r/geolocation/bounce_time_offset[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
The difference between the transmit time and the ground bounce time of the reference photons.
-
long_name:
ground bounce time offset
-
source:
ATL03 ATBD, Section 3.3
-
units:
seconds
/gt3r/geolocation/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
reference_photon_lat, reference_photon_lon
-
description:
Transmit time of the reference photon, measured in seconds from the atlas_sdp_gps_epoch. If there is no reference photon, this time corresponds to the approximate mid-point time associated with the along-track geolocation segment edge. 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:
Delta Time
-
source:
Derived
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/geolocation/reference_photon_index[
delta_time=
0
..163492]
(Type is Int32)
-
attributes
-
_FillValue:
0
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Index of the reference photon within the set of photons grouped within in segment. To recover the position of the reference photon within the photon-rate arrays, add ref_ph_ndx to the corresponding ph_ndx_beg and subtract 1. If no reference photon was selected, this value will indicate that the reference photon defaulted to the first photon. In the case of no photons within the segment (segment_ph_cnt=0), the value should be 0.
-
long_name:
Reference Photon Index
-
source:
ATL03 ATBD, Section 3.2
-
units:
counts
/gt3r/geolocation/altitude_sc[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
_FillValue:
1.7976931348623157e+308
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Height of the spacecraft above the WGS84 ellipsoid.
-
long_name:
Altitude
-
source:
ATL03g ATBD, Section 3.4
-
units:
meters
/gt3r/geolocation/segment_dist_x[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Along-track distance from the equator crossing to the start of the 20 meter geolocation segment.
-
long_name:
Segment Distance from EQC
-
source:
Derived
-
units:
meters
/gt3r/geolocation/neutat_delay_total[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time reference_photon_lat reference_photon_lon
-
description:
Total neutral atmosphere delay correction (wet+dry).
-
long_name:
Total Neutral Atmospheric Delay
-
source:
ATL03a ATBD
-
units:
meters
/gt3r/geophys_corr/tide_oc_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
description:
Surface deformation of the Earth due to loading from the centrifugal effect of polar motion upon the oceans (-2 to 2 mm).
-
long_name:
Ocean Pole Tide
-
source:
ATL03 ATBD, Section 6.3.6
-
units:
meters
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
/gt3r/geophys_corr/dem_flag[
delta_time=
0
..163492]
(Type is Int8)
-
attributes
-
_FillValue:
127
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Indicates source of the DEM height. Values: 0=None, 1=Arctic, 2=GMTED, 3=MSS, 4=Antarctic.
-
flag_meanings:
none arctic gmted mss antarctic
-
flag_values:
0, 1, 2, 3, 4
-
long_name:
dem source flag
-
source:
ATL03 ATBD Section 6.3
-
units:
1
-
valid_max:
4
-
valid_min:
0
/gt3r/geophys_corr/tide_ocean[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Ocean Tides including diurnal and semi-diurnal (harmonic analysis), and longer period tides (dynamic and self-consistent equilibrium). This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Ocean Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt3r/geophys_corr/tide_earth[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Tides
-
long_name:
Earth Tide
-
source:
ATL03 ATBD, Section 6.3.3
-
units:
meters
/gt3r/geophys_corr/dac[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Dynamic Atmospheric Correction (DAC) includes inverted barometer (IB) effect. This correction is not applied to the photon heights and provided only as supplemental information.
-
long_name:
Dynamic Atmosphere Correction
-
source:
ATL03 ATBD, Section 6.3.2
-
units:
meters
/gt3r/geophys_corr/tide_load[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Load Tide - Local displacement due to Ocean Loading (-6 to 0 cm).
-
long_name:
Load Tide
-
source:
ATL03 ATBD, Section 6.3.4
-
units:
meters
/gt3r/geophys_corr/dem_h[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Best available DEM (in priority of Arctic/Antarctic/GMTED/MSS) value at the location of the reference photon.
-
long_name:
DEM Height
-
source:
ATL03 ATBD Section 6.3
-
units:
meters
/gt3r/geophys_corr/tide_equilibrium[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
contentType:
referenceInformation
-
coordinates:
delta_time
-
description:
Long period equilibrium tide self-consistent with ocean tide model (+-0.04m). This correction is not applied to the photon heights and is provided only as a supplemental information.
-
long_name:
Long Period Equilibrium Tide
-
source:
ATL03 ATBD, Section 6.3.1
-
units:
meters
/gt3r/geophys_corr/geoid[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Geoid height above WGS-84 reference ellipsoid (range -107 to 86m). Not applied on the product; requested by higher-level products.
-
long_name:
Geoid
-
source:
ATL03 ATBD, Section 6.3.8
-
units:
meters
/gt3r/geophys_corr/delta_time[
delta_time=
0
..163492]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
description:
Elapsed seconds from the ATLAS SDP GPS Epoch, corresponding to the transmit time of the reference photon. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/geophys_corr/tide_pole[
delta_time=
0
..163492]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Solid Earth Pole Tide -Rotational deformation due to polar motion (-1.5 to 1.5 cm).
-
long_name:
Solid Earth Pole Tide
-
source:
ATL03 ATBD, Section 6.3.5
-
units:
meters
/gt3r/signal_find_output/ocean/bckgrd_mean[
delta_time=
0
..72590]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/ocean/bckgrd_sigma[
delta_time=
0
..72590]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/ocean/t_pc_delta[
delta_time=
0
..72590]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3r/signal_find_output/ocean/delta_time[
delta_time=
0
..72590]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/signal_find_output/ocean/z_pc_delta[
delta_time=
0
..72590]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3r/signal_find_output/sea_ice/bckgrd_mean[
delta_time=
0
..62236]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/sea_ice/bckgrd_sigma[
delta_time=
0
..62236]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/sea_ice/t_pc_delta[
delta_time=
0
..62236]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3r/signal_find_output/sea_ice/delta_time[
delta_time=
0
..62236]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/signal_find_output/sea_ice/z_pc_delta[
delta_time=
0
..62236]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3r/signal_find_output/land_ice/bckgrd_mean[
delta_time=
0
..19643]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/land_ice/bckgrd_sigma[
delta_time=
0
..19643]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/land_ice/t_pc_delta[
delta_time=
0
..19643]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3r/signal_find_output/land_ice/delta_time[
delta_time=
0
..19643]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/signal_find_output/land_ice/z_pc_delta[
delta_time=
0
..19643]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3r/signal_find_output/land/bckgrd_mean[
delta_time=
0
..5539]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/land/bckgrd_sigma[
delta_time=
0
..5539]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/land/t_pc_delta[
delta_time=
0
..5539]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3r/signal_find_output/land/delta_time[
delta_time=
0
..5539]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/signal_find_output/land/z_pc_delta[
delta_time=
0
..5539]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3r/signal_find_output/inlandwater/bckgrd_mean[
delta_time=
0
..17734]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The mean of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/inlandwater/bckgrd_sigma[
delta_time=
0
..17734]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The standard deviation of the number of background counts expected in one height bin of the histogram of width dzATM over time period, dtATM
-
long_name:
background counts per bin sigma
-
source:
ATL03 ATBD, Section 5
-
units:
counts
/gt3r/signal_find_output/inlandwater/t_pc_delta[
delta_time=
0
..17734]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
The histogram bin width (integration time) along-track used to find signal photons.
-
long_name:
bin width size
-
source:
ATL03 ATBD, Section 5
-
units:
seconds
/gt3r/signal_find_output/inlandwater/delta_time[
delta_time=
0
..17734]
(Type is Float64)
-
attributes
-
contentType:
physicalMeasurement
-
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:
Derived via Time Tagging
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/signal_find_output/inlandwater/z_pc_delta[
delta_time=
0
..17734]
(Type is Float32)
-
attributes
-
_FillValue:
3.402823466e+38
-
coordinates:
delta_time
-
description:
Height bin size of the histogram used to find signal photons.
-
long_name:
bin height size
-
source:
ATL03 ATBD, Section 5
-
units:
meters
/gt3r/heights/ph_id_count[
delta_time=
0
..4.548381E6]
(Type is Int8)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The photon event counter is part of photon ID and counts from 1 for each channel until reset by laser pulse counter.
-
long_name:
photon event counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt3r/heights/lat_ph[
delta_time=
0
..4.548381E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lon_ph
-
description:
Latitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Latitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
latitude
-
units:
degrees_north
-
valid_max:
90.
-
valid_min:
-90.
/gt3r/heights/dist_ph_along[
delta_time=
0
..4.548381E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Along-track distance in a segment projected to the ellipsoid of the received photon, based on the Along-Track Segment algorithm. Total along track distance can be found by adding this value to the sum of segment lengths measured from the start of the most recent reference groundtrack.
-
long_name:
Distance from equator crossing.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
/gt3r/heights/signal_conf_ph[
delta_time=
0
..4.548381E6]
[
ds_surf_type=
0
..4]
(Type is Int8)
-
attributes
-
contentType:
qualityInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Confidence level associated with each photon event selected as signal. 0=noise. 1=added to allow for buffer but algorithm classifies as background; 2=low; 3=med; 4=high). This parameter is a 5xN array where N is the number of photons in the granule, and the 5 rows indicate signal finding for each surface type (in order: land, ocean, sea ice, land ice and inland water). Events not associated with a specific surface type have a confidence level of -1. Events evaluated as TEP returns have a confidence level of -2.
-
flag_meanings:
possible_tep not_considered noise buffer low medium high
-
flag_values:
-2, -1, 0, 1, 2, 3, 4
-
long_name:
Photon Signal Confidence
-
source:
ATL03 ATBD, Section 5, Conf
-
units:
1
-
valid_max:
4
-
valid_min:
-2
/gt3r/heights/ph_id_pulse[
delta_time=
0
..4.548381E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The laser pulse counter is part of photon ID and counts from 1 to 200 and is reset for each new major frame.
-
long_name:
laser pulse counter
-
source:
Derived as part of Photon ID
-
units:
counts
/gt3r/heights/h_ph[
delta_time=
0
..4.548381E6]
(Type is Float32)
-
attributes
-
contentType:
physicalMeasurement
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Height of each received photon, relative to the WGS-84 ellipsoid including the geophysical corrections noted in Section 6. Please note that neither the geoid, ocean tide nor the dynamic atmosphere (DAC) corrections are applied to the ellipsoidal heights.
-
long_name:
Photon WGS84 Height
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
height
-
units:
meters
/gt3r/heights/ph_id_channel[
delta_time=
0
..4.548381E6]
(Type is Byte)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Channel number assigned for each received photon event. This is part of the photon ID. Values range from 1 to 120 to span all channels and rise/fall edges. Values 1 to 60 are for falling edge; PCE1 (1 to 20), PCE 2 (21 to 40) and PCE3 (41 to 60). Values 61 to 120 are for rising edge; PCE1 (61 to 80), PCE 2 (81 to 100) and PC3 (101 to 120).
-
long_name:
Receive channel id
-
source:
Derived as part of Photon ID
-
units:
1
-
valid_max:
120
-
valid_min:
1
/gt3r/heights/lon_ph[
delta_time=
0
..4.548381E6]
(Type is Float64)
-
attributes
-
coordinates:
delta_time lat_ph
-
description:
Longitude of each received photon. Computed from the ECF Cartesian coordinates of the bounce point.
-
long_name:
Longitude
-
source:
ATL03g ATBD, Section 3.4
-
standard_name:
longitude
-
units:
degrees_east
-
valid_max:
180.
-
valid_min:
-180.
/gt3r/heights/delta_time[
delta_time=
0
..4.548381E6]
(Type is Float64)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
lat_ph lon_ph
-
description:
The transmit time of a given photon, measured in seconds from the ATLAS Standard Data Product Epoch. Note that multiple received photons associated with a single transmit pulse will have the same delta_time. 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:
Operations
-
standard_name:
time
-
units:
seconds since 2018-01-01
/gt3r/heights/pce_mframe_cnt[
delta_time=
0
..4.548381E6]
(Type is UInt32)
-
attributes
-
contentType:
referenceInformation
-
coordinates:
delta_time lat_ph lon_ph
-
description:
The major frame counter is read from the digital flow controller in a given PCE card. The counter identifies individual major frames across diag and science packets. Used as part of the photon ID.
-
long_name:
PCE Major frame counter
-
source:
Retained from prior a_alt_science_ph packet
-
units:
counts
/gt3r/heights/dist_ph_across[
delta_time=
0
..4.548381E6]
(Type is Float32)
-
attributes
-
coordinates:
delta_time lat_ph lon_ph
-
description:
Across-track distance projected to the ellipsoid of the received photon from the reference ground track. This is based on the Along-Track Segment algorithm described in Section 3.1.
-
long_name:
Distance off RGT.
-
source:
ATL03 ATBD, Section 3.1
-
units:
meters
