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Header Descriptions

Keyword Content Description
Additional_Attribute Product-specific additional attributes
AutomaticQualityFlagExplan Automatic Quality flag explanation (per parameter)
Cycle A count of the number of exact repeats of this reference orbit
EquatorCrossingDate Date of the equator crossing
EquatorCrossingLong Longitude of equator crossing
EquatorCrossingTime Time of the equator crossing
InputPointer Name of each input product file used to created this prod-uct (one instances of this keyword appears in the product header record for each input product file used in creation of this product)
Instance The number of times that a specific reference orbit has been returned to during flight
instrument_short_name Short name of instrument (GLAS)
Instrument_State Flag word that indicates which redundant units (laser, detector, oscillator) of the GLAS instrument are in operation
Instrument_State_Date The date that corresponds to the Instrument_State. There are a maximum of two per granule.
Instrument_State_Time The time that corresponds to the Instrument_State. There are a maximum of two per granule.
LocalGranuleID File name of the granule
LocalVersionID Granule version number (auto-incrementing, nn in filenaming convention
Numhead Number of header records preceding product data records
OperationalQualityFlagExpl Operational Quality flag explanation (per parameter)
Orbit Number Orbit number
OrbitQuality Status word that states what type of orbit was used during processing of the data for the granule. It specifies the models used in the orbit determination program. This provides an indication of the quality of the orbits being applied to the data.
ParameterName Name of product-specific parameters for which additional information follows
PercentFullRate Percent of data for this granule that atmospheric parameters are provided at 40 Hz data rate
PercentGroundHit Percent of data for this granule that had a detected ground return of the transmitted laser pulse
PercentHighRate Percent of data for this granule that atmospheric parameters are provided at 5 Hz data rate
PercentLowRate Percent of data for this granule that atmospheric parameters are provided at 0.25 Hz data rate
PercentMediumRate Percent of data for this granule that atmospheric parameters are provided at 1 Hz data rate
Percent1064to532 Percent atmospheric profiles that use the 1064 nm profile data to provide estimated values for the saturated 532nm profiles
PGEVersion Version number of the GSAS software that generated this granule
platform_short_name Short name of spacecraft (Icesat)
ProductionDateTime Creation time of granule
QAPercentMissingData Percent of missing data (per parameter)
QAPercentOutofBounds Percent of out-of-bounds data (per parameter)
RangeBeginningDate Start date of data on the granule
RangeEndingDate End data of data on the granule
RangeBeginningTime Start time of day for data on this granule
Range_Bias The additive calibration correction in millimeters to apply to range based on the science team cal/val activities
Range_Bias_Date The date that corresponds to the first valid Range_Bias. There are a maximum of two per granule.
Range_Bias_Time The time that corresponds to the first valid Range_Bias. There are a maximum of two per granule.
RangeEndingTime End time of day for data on this granule
Recl Record length in bytes
ReferenceOrbit Assigned number for which exact orbital elements describe the exact repeat orbit pattern
ReprocessingPlanned Planned reprocessing status
ReprocessingActual Actual reprocessing status
sensor_short_name Short name of sensor (LaserALT)
ScienceQualityFlagExplana Science Quality flag explanation (per parameter)
ShortName GSAS Filetype
size_mb_ecs_data_granule Size (in MB) of the granule
SP_ICE_GLAS_EndBlock Integer SPICE block number within GLAS coverage scheme in which granule data ends
SP_ICE_PATH_NO Number which represents the GLAS SPICE path number
SP_ICE_GLAS_StartBlock Integer SPICE block number within GLAS coverage scheme in which granule data starts
time_between_contiguous_records Time between contiguous data records (in seconds)
Timing_Bias The time tag error determined by the calibration team that was added to the time tags to compute the true time of data as provided on the granule
Timing_Bias_Date The date that corresponds to the Timing_Bias. There are a maximum of two per granule.
Timing_Bias_Time The time of day that corresponds to the Timing_Bias. There are a maximum of two per granule.
Timing_Drift This is the ratio of the true time for a one second oscillator tick to nominal one
Timing_Drift_Date The date that corresponds to the Timing_Drift. There are a maximum of two per granule.
Timing_Drift_Time The time of day that corresponds to the Timing_Drift. There are a maximum of two per granule.
Track The unique number assigned for each repeat ground track (one orbit) of the reference orbit
Track_Segment Number assigned for the specific latitude segment (1 = +50 to +50, 2 = +50 to -50, 3 = -50 to -50, 4 = -50 to +50) of the track for the data
VersionID The ESDT version number that is to be used with this product

Product-Specific Header Elements

Product Parameter Name Attribute
GLA01 Range Flag
Percent Missing
Percent Out of Bounds
GLA02 PC_Profile Flag
Percent Missing
CD_Profile Flag
Percent Missing
GLA03 Data Flag
Percent Missing
Temperature Flag
Percent Out of Bounds
Voltage Flag
Percent Out of Bounds
GLA04 prap Flag
Percent Missing
Gyro Flag
Percent Missing
Laser Reference System Flag
Percent Missing
Star Tracker Flag
Percent Missing
Laser Pulse Array Flag
Percent Missing
Instrument Star Tracker Flag
Percent Missing
GLA05 Range Flag
Percent Missing
Percent Out of Bounds
GLA06 Surface Elevation Flag
Percent Missing
Percent Out of Bounds
Surface Roughness Flag
Percent Out of Bounds
Surface Reflectance Flag
Percent Out of Bounds
Surface Slope Flag
Percent Out of Bounds
GLA07 532nm Attenuated Backscatter  
1064nm Attenuated Backscatter  
GLA08 Aerosol Layer Heights  
Planetary Boundary Layer  
GLA09 Cloud Layer Heights  
GLA10 Cloud Backscatter Cross Section Profile  
Cloud Extinction Cross Section Profile  
Aerosol Backscatter Cross Section Profile  
Aerosol Extinction Cross Section Profile  
GLA11 Cloud Optical Depth  
Aerosol Optical Depth  
Planetary Boundary Layer Optical Depth  
GLA12 Surface Elevation Flag
Percent Out of Bounds
Surface Roughness Flag
Percent Out of Bounds
Surface Reflectance Flag
Percent Out of Bounds
Surface Slope Flag
Percent Out of Bounds
GLA13 Surface Elevation Flag
Percent Out of Bounds
Surface Roughness Flag
Percent Out of Bounds
Surface Reflectance Flag
Percent Out of Bounds
GLA14 Surface Elevation Flag
Percent Out of Bounds
Surface Roughness Flag
Percent Out of Bounds
Surface Reflectance Flag
Percent Out of Bounds
Surface Slope Flag
Percent Out of Bounds
GLA15 Surface Elevation Flag
Percent Out of Bounds
Surface Roughness Flag
Percent Out of Bounds