GLAH09 Product Data Dictionary

File-Level (Global) Attributes

Attribute Example Value
featureType timeSeries
ShortName GLAH09
title GLAS/ICESat L2 Global Cloud Heights for Multi-layer Clouds (HDF5)
comment The level 2 cloud layer height data with top and bottom heights, and ground heights are provided at a minimum of once per 4 seconds. Data granules will contain approximately 23 hours (14 orbits) of data.
summary GLAH09 contains the cloud layer heights for researchers. Cloud layer height data consist of top and bottom heights for up to 10 layers below 20 km at 0.25 hz and 5 hz (40hz for below 4 km). Ground heights are provided at each resolution. Each GLAH09 file was created from an equivalent GLA09 binary file. The data used to create the GLAH09 values are contained in the equivalent GLAHxx files for the GLAxx files. See the provenance metadata for the creation of the GLA09.
license http://nsidc.org/data/icesat/disclaimer.html
references http://nsidc.org/data/docs/daac/glas_icesat_l1_l2_global_atmosphere.gd.html (Guide Document for this product at NSIDC), http://nsidc.org/daac/icesat/index.html (GLAS Product page at NSIDC)
AccessConstraints Data may not be reproduced or distributed without including the CitationForExternalPublication for this product included in this Metadata. Data may not be distributed in an altered form without the written permission of the GLAS Science Team.
CitationforExternalPublication The data used in this study were produced by the GLAS Science Team at the ICESat Science Investigator-led Processing System (I-SIPS) at NASA/GSFC. The data archive site is the NSIDC DAAC.
contributor_role Data Originator, Investigator, Producer, Producer
contributor_name David W. Hancock (David.W.Hancock@nasa.gov), Bob E Schutz (schutz@utcsr.ae.utexas.edu), Jay Zwally (Jay.Zwally@nasa.gov), John P DiMarzio (John.P.Dimarzio.1@nasa.gov)
creator_name ICESat Science Investigator-led Processing System (I-SIPS)
creator_email David.W.Hancock@nasa.gov
publisher_name NSIDC User Services
publisher_email nsidc@nsidc.org
publisher_url http://nsidc.org/daac/icesat/index.html
platform Ice, Cloud, and Land Elevation Satellite (ICESat)
instrument Geoscience Laser Altimeter System (GLAS)
processing_level 2
date_created 2013-02-08T11:58:44
spatial_coverage_type Horizontal
history 2011-06-20T15:27:20 glas_atm 6.0.1 GLA09_633_2103_002_0407_0_01_0001.DAT, 2013-02-08T11:58:44.000000Z GLA09_h5_convert Version 1.1 (February 2013) out/GLAH09_633_2103_002_0407_0_01_0001.H5
geospatial_lat_min -90.0
geospatial_lat_max 90.0
geospatial_lon_min -180.0
geospatial_lon_max 180.0
geospatial_lat_units degrees_north
geospatial_lon_units degrees_east
keywords Earth Science > Atmosphere > Clouds > Cloud Height > Cloud Layer Heights, Earth Science > Atmosphere > Clouds > Cloud Vertical Distribution > Cloud Layer Heights
keywords_vocabulary GCMD Science Keywords Version 6.0
standard_vocabulary_name CF-1.6
naming_authority http://dx.doi.org
project Ice, Cloud, and Land Elevation Satellite (GLAS_HDF)
time_type UTC
date_type J2000
time_coverage_start 2003-11-18T01:51:38
time_coverage_end 2003-11-19T00:24:45
time_coverage_duration 81280
source Satellite Measurements
HDFVersion HDF5 1.8.9
identifier_file_uuid 599740C3-F062-4F49-A756-8A0DA37BC95B
identifier_product_doi 10.5067/ICESAT/GLAS/DATA202
identifier_product_type GLAH09
identifier_product_format_version 1.0
Conventions CF-1.6
institution National Aeronautics and Space Administration (NASA)


Group: /Data_4s

This group contains data with a rate of 0.25 HZ.

Dimension Scales

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
DS_UTCTime_4s DOUBLE
(UNLIMITED)
Transmit Time of First Shot in frame in J2000
(time)
seconds The transmit time of the first shot in the 4 second frame measured as 'UTC seconds' elapsed since Jan 1 2000 12:00:00 UTC. This time has been derived from the GPS time accounting for leap seconds. Rel 33 GLAS Binary Data NOT_SET
DS_Cloud_Layer_10 INTEGER
(UNLIMITED)
Cloud Layer Index
(NOT_SET)
NOT_SET This array contains the cloud layer index, up to 10 Constants NOT_SET

Group: Data_4s/Time

This group contains the 4s index and time-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
i_rec_ndx INTEGER
(UNLIMITED)
GLAS Record Index
(NOT_SET)
NOT_SET Unique index that relates this record to the corresponding record(s) in each GLAS data product. Rel 33 GLAS Binary Data DS_UTCTime_4s
shot_time_flg INTEGER_1
(UNLIMITED)
time correction flag
(NOT_SET)
NOT_SET Shot time;0=shot time is transmit time;1=shot time is ground bounce time

flag values flag_meanings
0, 1 transmit_time ground_bounce_time
Rel 33 GLAS Binary Data DS_UTCTime_4s
gps_time_flg INTEGER_1
(UNLIMITED)
time correction flag
(NOT_SET)
NOT_SET GPS time;0=no delta gps time correction applied to shot time;1=delta gps time correction applied to shot time

flag values flag_meanings
0, 1 not_applied applied
Rel 33 GLAS Binary Data DS_UTCTime_4s
pl_timing_flg INTEGER_1
(UNLIMITED)
time correction flag
(NOT_SET)
NOT_SET Post-launch timing;0=no post-launch timing bias applied;1=post-launch timing bias applied - see header for value

flag values flag_meanings
0, 1 not_applied applied
Rel 33 GLAS Binary Data DS_UTCTime_4s
ddelay_flg INTEGER_1
(UNLIMITED)
time correction flag
(NOT_SET)
NOT_SET Digitizer turn-on delay;0=digitizer turn-on delay accounted for in shot time - see header;1=digitizer turn-on delay not accounted for in shot time

flag values flag_meanings
0, 1 applied not_applied
Rel 33 GLAS Binary Data DS_UTCTime_4s
peaktp_flg INTEGER_1
(UNLIMITED)
time correction flag
(NOT_SET)
NOT_SET Peak of transmit pulse;0=time to peak of transmit pulse accounted for in shot time;1=time to peak of transmit pulse not accounted for in shot time

flag values flag_meanings
0, 1 applied not_applied
Rel 33 GLAS Binary Data DS_UTCTime_4s

Group: Data_4s/Geolocation

This group contains geolocation-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
d_lat DOUBLE
(UNLIMITED)
Profile Location, Latitude (at each time)
(latitude)
degrees_north Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 0.25 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_4s
d_lon DOUBLE
(UNLIMITED)
Profile Location, Longitude(at each time)
(longitude)
degrees_east Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 0.25 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_4s

Group: Data_4s/Flags

This group contains flags at 1 per 4 sec.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
i_AttFlg3 INTEGER_1
(UNLIMITED)
Attitude Flag 3
(NOT_SET)
NOT_SET Attitude Flag 3, 0=PAD used for geolocation, 1=PAD not used for geolocation.

flag values flag_meanings
0, 1 PAD_used PAD_not_used
Rel 33 GLAS Binary Data DS_UTCTime_4s

Group: Data_4s/LRCloudLayer

This group contains the(0.25HZ) Low resolution cloud layer parameters. ( layers once per 4 seconds).

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_LRcld_bot REAL
(UNLIMITED, 10)
Low Resolution Cloud Bottom at 532 nm
(NOT_SET)
meters Low resolution height above the reference ellipsoid of the bottom of a cirrus, thin, or dense cloud layer in the atmosphere. There can be up to 10 cloud layers in an atmospheric profile. The low resolution data occurs at the rate of once per 4 seconds. Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRcld_top REAL
(UNLIMITED, 10)
Low Resolution Cloud Top at 532 nm
(NOT_SET)
meters Low resolution height above the reference ellipsoid of the top of a cirrus, thin, or dense cloud layer in the atmosphere. There can be up to 10 cloud layers in an atmospheric profile. The low resolution data occurs at the rate of once per 4 seconds. Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRcld_grd REAL
(UNLIMITED)
Low Resolution Ground Detection at 532 nm
(NOT_SET)
meters The height from the reference ellipsoid of the ground as detected by the low resolution cloud processing algorithms. A value of -127 indicates that the ground was searched for, but not detected. Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRg_cldbot_pres REAL
(UNLIMITED, 10)
Low Resolution 532 nm Cloud Bottom Pressure
(NOT_SET)
hPa Low Resolution 532 nm Cloud Bottom Pressure Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRg_cldbot_relh REAL
(UNLIMITED, 10)
Low Resolution 532 nm Cloud Bottom Relative Humidity
(NOT_SET)
percent Low Resolution 532 nm Cloud Bottom Relative Humidity Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRg_cldbot_temp REAL
(UNLIMITED, 10)
Low Resolution 532 nm Cloud Bottom Temperature
(NOT_SET)
degree Celsius Low Resolution 532 nm Cloud Bottom Temperature Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRg_cldtop_pres REAL
(UNLIMITED, 10)
Low Resolution 532 nm Cloud Top Pressure
(NOT_SET)
hPa Low Resolution 532 nm Cloud Top Pressure Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRg_cldtop_relh REAL
(UNLIMITED, 10)
Low Resolution 532 nm Cloud Top Relative Humidity
(NOT_SET)
percent Low Resolution 532 nm Cloud Top Relative Humidity Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRg_cldtop_temp REAL
(UNLIMITED, 10)
Low Resolution 532 nm Cloud Top Temperature
(NOT_SET)
degree Celsius Low Resolution 532 nm Cloud Top Temperature Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cld_bot REAL
(UNLIMITED, 10)
Elevation of Bottom of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
meters Elevation of Bottom of Cloud Layers Detected in 1064 nm at Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cld_top REAL
(UNLIMITED, 10)
Elevation of Top of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
meters Elevation of top of cloud layers detected in 1064 nm at low resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cldbot_pres REAL
(UNLIMITED, 10)
Pressure of Bottom of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
hPa Pressure of Bottom of Cloud Layers Detected in 1064 nm at Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cldbot_relh REAL
(UNLIMITED, 10)
Relative Humidity of Bottom of Cloud Layers Detected in 1064 nm Low Resolution
(NOT_SET)
percent Relative Humidity of Bottom of Cloud Layers Detected in 1064 nm Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cldbot_temp REAL
(UNLIMITED, 10)
Temperature of Bottom of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
degree Celsius Temperature of Bottom of Cloud Layers Detected in 1064 nm at Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cldtop_pres REAL
(UNLIMITED, 10)
Pressure of Top of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
hPa Pressure of Top of Cloud Layers Detected in 1064 nm at Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cldtop_relh REAL
(UNLIMITED, 10)
Relative Humidity of Top of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
percent Relative Humidity of Top of Cloud Layers Detected in 1064 nm at Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
r_LRir_cldtop_temp REAL
(UNLIMITED, 10)
Temperature of Top of Cloud Layers Detected in 1064 nm at Low Resolution
(NOT_SET)
degree Celsius Temperature of Top of Cloud Layers Detected in 1064 nm at Low Resolution data rate (1 per 4 sec). Rel 33 GLAS Binary Data DS_UTCTime_4s
i_LRC_af INTEGER_1
(UNLIMITED)
Low Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET availability flag: Tells how many cloud layers were found at this resolution from the 532 nm channel. value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for, but not detected

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected found_1 found_2 found_3 found_4 found_5 found_6 found_7 found_8 found_9 found_10 found_11 found_12 found_13 found_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_4s
i_LRC_qf INTEGER_1
(UNLIMITED, 10)
Low Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET qf=quality flag: value 15 = cloud layers were not searched for - either bad data or cloud layers were not found at a coarser resolution; value 1 = low chance of being a cloud; value 2 = moderate; value 3 = high; value 4 = no doubt -- based upon noise-to-signal and geometric thickness evaluation; Value 14 = height of bottom of lowest detected layer in profile very uncertain because ground signal was not detected.

flag values flag_meanings
1, 2, 3, 4, 14, 15 low_chance moderate high no_doubt uncertain not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_4s
i_LRC_df INTEGER_1
(UNLIMITED, 10)
Low Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET diurnal flag: This tells whether a given layer would be detected during normal daylight conditions. value 0 = layer would not have been detected in typical daytime background; value 1 = layer would have been detected in daylight

flag values flag_meanings
0, 1 would_not_have_been_detected would_have_been_detected
Rel 33 GLAS Binary Data DS_UTCTime_4s
i_LRCir_af INTEGER_1
(UNLIMITED)
Low Resolution 1064 nm Cloud Layer QA Flag
(NOT_SET)
NOT_SET availability flag: It provides the number of cloud layers determined from the 1064 nm data. value 0 = layers searched for but not detected; value 15 = cloud layers not searched for.

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected found_1 found_2 found_3 found_4 found_5 found_6 found_7 found_8 found_9 found_10 found_11 found_12 found_13 found_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_4s
i_LRir_QAflag INTEGER_1
(UNLIMITED, 10)
Low Resolution 1064 nm Cloud Layer QA Flag
(NOT_SET)
NOT_SET quality flag: value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for but not detected; values 1-14 indicate increasing confidence of good cloud retrieval (value 1 = least confidence, value 14 = greatest confidence).

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected confidence_1 confidence_2 confidence_3 confidence_4 confidence_5 confidence_6 confidence_7 confidence_8 confidence_9 confidence_10 confidence_11 confidence_12 confidence_13 confidence_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_4s


Group: /Data_1HZ

This group contains data with a rate of 1HZ. 1Hz data may be indexed to the 40HZ data using the i_rec_ndx parameter in each respective time group.

Dimension Scales

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
DS_UTCTime_1 DOUBLE
(UNLIMITED)
Transmit Time of First Shot in frame in J2000
(time)
seconds The transmit time of the first shot in the 1 second frame measured as 'UTC seconds' elapsed since Jan 1 2000 12:00:00 UTC. This time has been derived from the GPS time accounting for leap seconds. Rel 33 GLAS Binary Data NOT_SET
DS_Cloud_Layer_10 INTEGER
(UNLIMITED)
Cloud Layer Index
(NOT_SET)
NOT_SET This array contains the cloud layer index, up to 10 Constants NOT_SET

Group: Data_1HZ/Time

This group contains the 1HZ index and time-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
i_rec_ndx INTEGER
(UNLIMITED)
GLAS Record Index
(NOT_SET)
NOT_SET Unique index that relates this record to the corresponding record(s) in each GLAS data product. Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/Geolocation

This group contains geolocation-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
d_lat DOUBLE
(UNLIMITED)
Profile Location, Latitude
(latitude)
degrees_north Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 1 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_1
d_lon DOUBLE
(UNLIMITED)
Profile Location, Longitude
(longitude)
degrees_east Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 1 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/PBL

This group contains information relating to the Clouds.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_Total_CloudCov REAL
(UNLIMITED)
Total Cloud Cover
(NOT_SET)
percent Total Cloud Cover Rel 33 GLAS Binary Data DS_UTCTime_1
r_PBL_Layer_ht REAL
(UNLIMITED)
PBL Layer Height from Met Data
(NOT_SET)
meters PBL Layer Height from Met Data Rel 33 GLAS Binary Data DS_UTCTime_1
r_atm_dem REAL
(UNLIMITED)
DEM value at current location from 1 km x 1 km grid
(NOT_SET)
meters Surface height value for current location from 1 km x 1 km grid Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/Geophysical

This group contains geophysical parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_topo_elev REAL
(UNLIMITED)
Topographic elevation of surface above geoid
(NOT_SET)
meters Topographic elevation of surface above geoid based upon POD, PAD, and geoid Rel 33 GLAS Binary Data DS_UTCTime_1
r_Surface_pres REAL
(UNLIMITED)
Surface Pressure
(surface_air_pressure)
hPa Atmospheric pressure at Earth's surface level measured in hPa and derived from the meteorological data files. Rel 33 GLAS Binary Data DS_UTCTime_1
r_Surface_relh REAL
(UNLIMITED)
Surface Relative Humidity
(relative_humidity)
percent Atmospheric relative humidity at Earth's surface level measured as a percentage and derived from the meteorological data files. Rel 33 GLAS Binary Data DS_UTCTime_1
r_Surface_temp REAL
(UNLIMITED)
Surface Temperature
(surface_temperature)
degree Celsius Atmospheric temperature at Earth's surface level measured in degrees Celsius and derived from the meteorological data files. Rel 33 GLAS Binary Data DS_UTCTime_1
r_Surface_wdir REAL
(UNLIMITED)
Surface Wind Direction Azimuth from North
(NOT_SET)
degrees Wind direction at Earth's surface level measured in degrees of azimuth from North and derived from the meteorological data files. Rel 33 GLAS Binary Data DS_UTCTime_1
r_Surface_wind REAL
(UNLIMITED)
Surface Wind Speed
(NOT_SET)
meters/second Wind speed at Earth's surface level measured in km/hour and derived from the meteorological data files. Rel 33 GLAS Binary Data DS_UTCTime_1
r_Spec_Humid REAL
(UNLIMITED)
Specific Humidity
(NOT_SET)
gram/kilogram Specific humidity 2m above ground. Rel 33 GLAS Binary Data DS_UTCTime_1
r_Temp2mAbvGrnd REAL
(UNLIMITED)
Temperature 2m Above Ground Level
(NOT_SET)
degrees Celsius Temperature 2m Above Ground Level Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/Quality

This group contains flags indicating the quality or suitability of data.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
orbit_pred_flg INTEGER_1
(UNLIMITED)
Orbit flag
(NOT_SET)
NOT_SET Predicted or precision orbit;0=precision orbit used;1=predicted orbit used;2=on-board orbit used

flag values flag_meanings
0, 1, 2 precision_orbit_used predicted_orbit_used on-board_orbit_used
Rel 33 GLAS Binary Data DS_UTCTime_1
orbit_man_flg INTEGER_1
(UNLIMITED)
Orbit flag
(NOT_SET)
NOT_SET Maneuvers;0=no maneuvers;1=maneuvers occurred during this record; orbit degraded

flag values flag_meanings
0, 1 no_maneuvers maneuvers orbit_degraded
Rel 33 GLAS Binary Data DS_UTCTime_1
orbit_model_flg INTEGER_1
(UNLIMITED)
Orbit flag
(NOT_SET)
NOT_SET Model problems;0=no model problems;1=model problems; orbit RMS > 5 cm; required accuracy not met

flag values flag_meanings
0, 1 no_problems problems
Rel 33 GLAS Binary Data DS_UTCTime_1
orbit_att_flg INTEGER_1
(UNLIMITED)
Orbit flag
(NOT_SET)
NOT_SET Attitude;0=instrument attitude used for orbit;1=modeled attitude used, possible orbit degradation

flag values flag_meanings
0, 1 instrument_attitude_used modeled_attitude_used possible_orbit_degradation
Rel 33 GLAS Binary Data DS_UTCTime_1
orbit_array_flg INTEGER_1
(UNLIMITED)
Orbit flag
(NOT_SET)
NOT_SET Solar ray orientation;0=solar ray orientation used from measurement;1=modeled solar ray orientation, possible orbit degradation

flag values flag_meanings
0, 1 solar_ray_orientation_from_measurement modeled_solar_ray_orientation
Rel 33 GLAS Binary Data DS_UTCTime_1
orbit_gps_flg INTEGER_1
(UNLIMITED)
Orbit flag
(NOT_SET)
NOT_SET GPS;0=no GPS data outage;1=GPS data missing from portion of this record, possible degradation

flag values flag_meanings
0, 1 no_GPS_data_outage GPS_data_missing
Rel 33 GLAS Binary Data DS_UTCTime_1
att_offnadir_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET Off-nadir angle; 0=off-nadir angle within limits;1=large off-nadir angle

flag values flag_meanings
0, 1 off-nadir_angle_within_limits large_off-nadir_angle
Rel 33 GLAS Binary Data DS_UTCTime_1
att_oceansw_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET Ocean sweep;0=non-ocean sweep, 1=within time frame of ocean sweep

flag values flag_meanings
0, 1 non-ocean_sweep ocean_sweep
Rel 33 GLAS Binary Data DS_UTCTime_1
att_pointing_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET Target of opportunity off-pointing;0=not within target of opportunity off-pointing 1=within time of target of opportunity off-pointing

flag values flag_meanings
0, 1 not_TOO TOO
Rel 33 GLAS Binary Data DS_UTCTime_1
att_steering_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET Steering to reference track;0=not within target of opportunity off-pointing 1=within time of target of opportunity off-pointing

flag values flag_meanings
0, 1 not_TOO TOO
Rel 33 GLAS Binary Data DS_UTCTime_1
att_actual_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET 0=i_AttFlg_1 through i_AttFlg_3 have been set based on actual data 1=i_AttFlg_1 through i_AttFlg_3 have not been set - IGNORE these flags

flag values flag_meanings
0, 1 actual ignore
Rel 33 GLAS Binary Data DS_UTCTime_1
att_ist_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET IST data;0 = IST data is good 1 = Missing IST for at least a portion of the time of this frame 2 = Noisy IST for at least a portion of the time of this frame 3 = Noisy and missing IST for at least a portion of the time of this frame

flag values flag_meanings
0, 1, 2, 3 IST_data_good IST_missing IST_noisy IST_noisy_and_missing
Rel 33 GLAS Binary Data DS_UTCTime_1
att_gyro_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET GYRO data;0 = GYRO data is good 1 = Missing GYRO for at least a portion of the time of this frame 2 = Noisy GYRO for at least a portion of the time of this frame 3 = Noisy and missing GYRO for at least a portion of the time of this frame

flag values flag_meanings
0, 1, 2, 3 GYRO_data_good GYRO_data_missing GYRO_data_noisy GYRO_data_noisy_and_missing
Rel 33 GLAS Binary Data DS_UTCTime_1
att_lrs_flg INTEGER_1
(UNLIMITED)
Attitude flag
(NOT_SET)
NOT_SET LRS Data;0 = LRS data good, consists of star, laser and CRS 1 = LRS data good, but no star data for at least a portion of this frame 2 = LRS data good, but no laser data for at least a portion of this frame 3 = LRS data good, but no CRS data for at least a portion of this frame 4 = LRS data good, but only CRS data for at least a portion of this frame 5 = LRS data good, but only laser data for at least a portion of this frame 6 = LRS data good, but only star data for at least a portion of this frame 7 = Missing LRS for at least a portion of the time of this frame

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7 LRS_data_good LRS_data_good_but_no_star_data LRS_data_good_but_no_laser_data LRS_data_good_but_no_CRS_data LRS_data_good_but_only_some_CRS_data LRS_data_good_but_only_some_laser_data LRS_data_good_but_only_some_star_data some_missing_LRS_data
Rel 33 GLAS Binary Data DS_UTCTime_1
i_LidarQF INTEGER_1
(UNLIMITED)
Lidar Frame quality flag
(NOT_SET)
NOT_SET Lidar frame quality flag. 0=good data, 1=data unsuitable for L2 processing due to weak 532 laser energy or high background.

flag values flag_meanings
0, 1 good unsuitable
Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/Flags

This group contains flags indicating the quality or suitability of data.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
surf_ld_flg INTEGER_1
(UNLIMITED)
Region Type
(NOT_SET)
NOT_SET Region type;0=no Land;1=Land

flag values flag_meanings
0, 1 no_land land
Rel 33 GLAS Binary Data DS_UTCTime_1
surf_si_flg INTEGER_1
(UNLIMITED)
Region Type
(NOT_SET)
NOT_SET Region type;0=no Sea Ice;1=Sea Ice

flag values flag_meanings
0, 1 no_seaice seaice
Rel 33 GLAS Binary Data DS_UTCTime_1
surf_oc_flg INTEGER_1
(UNLIMITED)
Region Type
(NOT_SET)
NOT_SET Region type;0=no Ocean;1=Ocean

flag values flag_meanings
0, 1 no_ocean ocean
Rel 33 GLAS Binary Data DS_UTCTime_1
surf_is_flg INTEGER_1
(UNLIMITED)
Region Type
(NOT_SET)
NOT_SET Region type;0=no Ice Sheet;1=Ice Sheet

flag values flag_meanings
0, 1 no_icesheet icesheet
Rel 33 GLAS Binary Data DS_UTCTime_1
i_atm_char_conf INTEGER_1
(UNLIMITED)
Atmosphere Characterization Flag Confidence
(NOT_SET)
N/A Confidence level ascribed to the atmosphere characterization flag. 0=not applicable (for contamination flag values of 9 or 10). 1: low confidence. 2: reasonable confidence. 3: high confidence.

flag values flag_meanings
0, 1, 2, 3 not_applicable low_confidence reasonable_confidence high_confidence
Rel 33 GLAS Binary Data DS_UTCTime_1
i_atm_char_flag INTEGER_1
(UNLIMITED)
Atmosphere Characterization Flag
(NOT_SET)
NOT_SET Flag to characterize cloud and blowing snow state of the atmosphere
0 clear
1 high cloud (> 5 km) low optical depth
2 high cloud (> 5 km), high optical depth
3 mid cloud (>2, <=5 km) low optical depth
4 mid cloud (>2, <=5 km) high optical depth
5 low cloud (> 500 m, <=2 km), low optical depth
6 low cloud (> 500 m, <=2 km), high optical depth
7 blowing snow or fog (< 500 m), low optical depth
8 blowing snow or fog (< 500 m), high optical depth
9 not tested
10 data quality insufficient to assign flag


flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 clear high_cloud_low_opt_depth high_cloud_high_opt_depth mid_cloud_low_opt_depth mid_cloud_high_opt_depth low_cloud_low_opt_depth low_cloud_high_opt_depth b_snow_or_fog_low_opt_depth b_snow_or_fog_high_opt_depth not_tested poor_quality
Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/Angle

This group contains beam pointing angle information.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_beam_azimuth REAL
(UNLIMITED)
Azimuth
(NOT_SET)
degrees The direction, eastwards from north, of the laser beam vector as seen by an observer at the laser ground spot viewing toward the spacecraft (i.e., the vector from the ground to the spacecraft). When the spacecraft is precisely at the geodetic zenith, the value will be 99999 degrees. Rel 33 GLAS Binary Data DS_UTCTime_1
r_beam_coelev REAL
(UNLIMITED)
Co-elevation
(NOT_SET)
degrees Co-elevation (CE) is direction from vertical of the laser beam as seen by an observer located at the laser ground spot. Rel 33 GLAS Binary Data DS_UTCTime_1
r_pad_angle REAL
(UNLIMITED)
PAD Angle
(NOT_SET)
degrees Attitude angle calculated from PAD and POD. Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/Reflectivity

This group contains reflectivity information.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_SolAng REAL
(UNLIMITED)
Solar Angle
(NOT_SET)
degrees Solar Angle above or below the plane tangent to the ellipsoid surface at the laser spot. Positive values mean the sun is above the horizon, while negative values mean it is below the horizon. The effect of atmospheric refraction is not included. This is a low-precision value, with approximately one degree accuracy. Rel 33 GLAS Binary Data DS_UTCTime_1

Group: Data_1HZ/MRCloudLayer

This group contains the (1HZ) medium resolution cloud layer parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_MRcld_bot REAL
(UNLIMITED, 10)
Medium Resolution Cloud Bottom at 532 nm
(NOT_SET)
meters Medium resolution height above the reference ellipsoid of the bottom of a cirrus, thin, or dense cloud layer in the atmosphere. There can be up to 10 cloud layers in an atmospheric profile. The medium resolution data occurs at the rate of once per second. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRcld_top REAL
(UNLIMITED, 10)
Medium Resolution Cloud Top at 532 nm
(NOT_SET)
meters Medium resolution height above the reference ellipsoid of the top of a cirrus, thin, or dense cloud layer in the atmosphere. There can be up to 10 cloud layers in an atmospheric profile. The medium resolution data occurs at the rate of once per second. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRg_cldbot_pres REAL
(UNLIMITED, 10)
Medium Resolution 532 nm Cloud Bottom Pressure
(NOT_SET)
hPa Medium Resolution 532 nm Cloud Bottom Pressure Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRg_cldbot_relh REAL
(UNLIMITED, 10)
Medium Resolution 532 nm Cloud Bottom Relative Humidity
(NOT_SET)
percent Medium Resolution 532 nm Cloud Bottom Relative Humidity Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRg_cldbot_temp REAL
(UNLIMITED, 10)
Medium Resolution 532 nm Cloud Bottom Temperature
(NOT_SET)
degree Celsius Medium Resolution 532 nm Cloud Bottom Temperature Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRg_cldtop_pres REAL
(UNLIMITED, 10)
Medium Resolution 532 nm Cloud Top Pressure
(NOT_SET)
hPa Medium Resolution 532 nm Cloud Top Pressure Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRg_cldtop_relh REAL
(UNLIMITED, 10)
Medium Resolution 532 nm Cloud Top Relative Humidity
(NOT_SET)
percent Medium Resolution 532 nm Cloud Top Relative Humidity Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRg_cldtop_temp REAL
(UNLIMITED, 10)
Medium Resolution 532 nm Cloud Top Temperature
(NOT_SET)
degree Celsius Medium Resolution 532 nm Cloud Top Temperature Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cld_bot REAL
(UNLIMITED, 10)
Elevation of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution
(NOT_SET)
meters Elevation of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cld_top REAL
(UNLIMITED, 10)
Elevation of Top of Cloud Layers Detected in 1064 nm at Medium Resolution
(NOT_SET)
meters Elevation of Top of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cldbot_pres REAL
(UNLIMITED, 10)
Pressure of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution
(NOT_SET)
hPa Pressure of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cldbot_relh REAL
(UNLIMITED, 10)
Relative Humidity of Bottom of Cloud Layers Detected in 1064 nm at MR
(NOT_SET)
percent Relative Humidity of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cldbot_temp REAL
(UNLIMITED, 10)
Temperature of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution
(NOT_SET)
degree Celsius Temperature of Bottom of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cldtop_pres REAL
(UNLIMITED, 10)
Pressure of Top of Cloud Layers Detected in 1064 nm at Medium Resolution
(NOT_SET)
hPa Pressure of Top of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cldtop_relh REAL
(UNLIMITED, 10)
Relative Humidity of Top of Cloud Layers in 1064 nm at Medium Resolution
(NOT_SET)
percent Relative Humidity of Top of Cloud Layers in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRir_cldtop_temp REAL
(UNLIMITED, 10)
Temperature of Top of Cloud Layers Detected in 1064 nm at Medium Resolution
(NOT_SET)
degree Celsius Temperature of Top of Cloud Layers Detected in 1064 nm at Medium Resolution data rate. Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRcld_grd REAL
(UNLIMITED)
Medium Resolution Ground Detection at 532 nm
(NOT_SET)
meters The height above the reference ellipsoid of the ground as detected by the medium resolution cloud processing algorithms. A value of -127 indicates that the ground was searched for, but not detected. Rel 33 GLAS Binary Data DS_UTCTime_1
i_MRC_af INTEGER_1
(UNLIMITED)
Medium Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Availability flag: Tells how many cloud layers were found at this resolution. The total number of layers found is the sum of those found using the 532 channel and the 1064 channel (thus, this number will generally be larger than the actual number of layers present). value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for, but not detected

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected found_1 found_2 found_3 found_4 found_5 found_6 found_7 found_8 found_9 found_10 found_11 found_12 found_13 found_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_1
i_MRC_qf INTEGER_1
(UNLIMITED, 10)
Medium Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Quality flag: value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for but not detected; value 1 = low chance of being a cloud; value 2 = moderate; value 3 = high; value 4 = no doubt

flag values flag_meanings
0, 1, 2, 3, 4, 15 not_detected low_chance moderate high no_doubt not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_1
i_MRC_uf INTEGER_1
(UNLIMITED, 10)
Medium Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Use flag: Tells which channel was used to detect the layer; value 0 = cloud layer was derived from 532 channel data; value 2 = cloud layer was derived from the 1064 channel data

flag values flag_meanings
0, 2 532_channel_data 1064_channel_data
Rel 33 GLAS Binary Data DS_UTCTime_1
i_MRC_df INTEGER_1
(UNLIMITED, 10)
Medium Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Diurnal flag: This tells whether a given layer would be detected during normal daylight conditions. value 0 = layer would not have been detected in typical daytime background; value 1 = layer would have been detected in dayligh

flag values flag_meanings
0, 1 would_not_have_been_detected would_have_been_detected
Rel 33 GLAS Binary Data DS_UTCTime_1
i_MRCir_af INTEGER_1
(UNLIMITED)
Medium Resolution 1064 nm Cloud Layer QA Flag
(NOT_SET)
NOT_SET Availability flag. It provides the number of cloud layers determined from the 1064 nm data. value 0 = layers searched for but not detected; value 15 = cloud layers not searched for.

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected found_1 found_2 found_3 found_4 found_5 found_6 found_7 found_8 found_9 found_10 found_11 found_12 found_13 found_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_1
i_MRir_QAflag INTEGER_1
(UNLIMITED, 10)
Medium Resolution 1064 nm Cloud Layer QA Flag
(NOT_SET)
NOT_SET Quality flag: value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for but not detected; values 1-14 indicate increasing confidence of good cloud retrieval (value 1 = least confidence, value 14 = greatest confidence).

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected confidence_1 confidence_2 confidence_3 confidence_4 confidence_5 confidence_6 confidence_7 confidence_8 confidence_9 confidence_10 confidence_11 confidence_12 confidence_13 confidence_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_1
r_MRcld_pct REAL
(UNLIMITED, 10)
Percentage of Saturated Bins in Medium Resolution Cloud Layers at 532 nm
(NOT_SET)
NOT_SET Percentage of saturated bins in medium resolution cloud layers Rel 33 GLAS Binary Data DS_UTCTime_1


Group: /Data_5HZ/

This group contains data with a rate of 5HZ. 5Hz data may be indexed to the 1HZ data using the i_rec_ndx parameter in each respective time group.

Dimension Scales

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
DS_UTCTime_5 DOUBLE
(UNLIMITED)
Transmit Time of First Shot in frame in J2000
(time)
seconds The transmit time of five shots in the 1 second frame measured as 'UTC seconds' elapsed since Jan 1 2000 12:00:00 UTC. This time has been derived from the GPS time accounting for leap seconds. Rel 33 GLAS Binary Data NOT_SET
DS_Cloud_Layer_10 INTEGER
(UNLIMITED)
Cloud Layer Index
(NOT_SET)
NOT_SET This array contains the cloud layer index, up to 10 Constants NOT_SET

Group: Data_5HZ/Time

This group contains the 5HZ index and time-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
i_rec_ndx INTEGER
(UNLIMITED)
GLAS Record Index
(NOT_SET)
NOT_SET Unique index that relates this record to the corresponding record(s) in each GLAS data product. Rel 33 GLAS Binary Data DS_UTCTime_5
i_shot_count INTEGER
(UNLIMITED)
GLAS shot counter
(NOT_SET)
NOT_SET Identifies each laser shot within a record index. A combination of i_rec_ndx and i_shot_count can be used to uniquely identify each GLAS laser shot. Rel 33 GLAS Binary Data DS_UTCTime_5

Group: Data_5HZ/Geolocation

This group contains geolocation-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
d_lat DOUBLE
(UNLIMITED)
Profile Location, Latitude (at each time)
(latitude)
degrees_north Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 5 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_5
d_lon DOUBLE
(UNLIMITED)
Profile Location, Longitude(at each time)
(longitude)
degrees_east Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 5 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_5

Group: Data_5HZ/BlowingSnow5hz

This group contains the 5HZ blowing snow parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_blow_snow_erd REAL
(UNLIMITED)
Blowing Snow Range Delay
(NOT_SET)
millimeters An estimate of the range delay caused by blowing snow. Rel 33 GLAS Binary Data DS_UTCTime_5
r_blow_snow_ht REAL
(UNLIMITED)
Blowing Snow Height
(NOT_SET)
meters Represents the maximum height above the surface of the blowing snow layer. Rel 33 GLAS Binary Data DS_UTCTime_5
r_blow_snow_od REAL
(UNLIMITED)
Blowing Snow Optical Depth
(NOT_SET)
NOT_SET An estimate of the optical depth of the blowing snow layer. Rel 33 GLAS Binary Data DS_UTCTime_5
i_blow_snow_conf INTEGER_1
(UNLIMITED)
Blowing Snow Confidence
(NOT_SET)
NOT_SET A number that indicates the degree of confidence that this is indeed blowing snow. Blowing snow confidence ranges from 0 - 15 and has the following meanings: 0: profile tested, but no blowing snow detected 1 - 5: Good blowing snow detection using the 1064 channel. 1 is lowest confidence that layer is blowing snow, 5 is highest confidence. 6: Layer suspected of being low cloud (such as fog), or seemingly too thick to be blowing snow (> 1.0 km thick) as determined from 1064 channel. 7 - 12: Good blowing snow detection using the 532 channel. 7 is lowest confidence that layer is blowing snow, 12 is highest confidence. 13: Layer suspected of being low cloud (such as fog), or seemingly too thick to be blowing snow (> 1.0 km thick) as determined from 532 channel. 14: Wind speed < 5 m/s or ground stroke not detected (the latter case indicating overlying thick cloud) 15: Signal not examined for blowing snow (could be because it is closer to the equator than plus or minus 60 degrees latitude, or not over sea ice or land)

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 no_b_s good_b_s_1064_1 good_b_s_1064_2 good_b_s_1064_3 good_b_s_1064_4 good_b_s_1064_5 suspctd_low_cl_1064 good_b_s_532_7 good_b_s_532_8 good_b_s_532_9 good_b_s_532_10 good_b_s_532_11 good_b_s_532_12 suspctd_low_cl_532 low_wind_sp_thick_cloud sig_not_exam
Rel 33 GLAS Binary Data DS_UTCTime_5

Group: Data_5HZ/HRCloudLayer

This group contains the 5HZ high resolution cloud layer parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_HRcld_grd REAL
(UNLIMITED)
High Resolution Ground Detection at 532 nm
(NOT_SET)
meters The height above the reference ellipsoid of the ground as detected by the high resolution cloud processing algorithms. A value of -127 indicates that the ground was searched for, but not detected. Rel 33 GLAS Binary Data DS_UTCTime_5
r_HRcld_bot REAL
(UNLIMITED, 10)
High Resolution Cloud Bottom at 532 nm
(NOT_SET)
meters High resolution height above the reference ellipsoid of the bottom of a cirrus, thin, or dense cloud layer below 10KM in the atmosphere. There can be up to 10 cloud layers in an atmospheric profile. The high resolution data occurs at the rate of 5 per second. Rel 33 GLAS Binary Data DS_UTCTime_5
r_HRcld_top REAL
(UNLIMITED, 10)
High Resolution Cloud Top at 532 nm
(NOT_SET)
meters High resolution height above the reference ellipsoid of the top of a cirrus, thin, or dense cloud layer below 10 KM in the atmosphere. There can be up to 10 cloud layers in an atmospheric profile. The high resolution data occurs at the rate of 5 per second. Rel 33 GLAS Binary Data DS_UTCTime_5
i_HRC_af INTEGER_1
(UNLIMITED)
High Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET availability flag: Tells how many cloud layers were found (from the 532 channel) at this resolution. value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for, but not detected

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected found_1 found_2 found_3 found_4 found_5 found_6 found_7 found_8 found_9 found_10 found_11 found_12 found_13 found_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_5
i_HRC_qf INTEGER_1
(UNLIMITED, 10)
High Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET quality flag: value 15 = cloud layers were not searched for - either bad data or cloud layers were not found at a coarser resolution; value 1 = low chance of being a cloud; value 2 = moderate; value 3 = high; value 4 = no doubt -- based upon noise-to-signal and geometric thickness evaluation; Value 14 = height of bottom of lowest detected layer in profile very uncertain because ground signal was not detected.

flag values flag_meanings
1, 2, 3, 4, 14, 15 low_chance moderate high no_doubt uncertain not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_5
i_HRC_df INTEGER_1
(UNLIMITED, 10)
High Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET diurnal flag: This tells whether a given layer would be detected during normal daylight conditions. value 0 = layer would not have been detected in typical daytime background; value 1 = layer would have been detected in daylight

flag values flag_meanings
0, 1 would_not_have_been_detected would_have_been_detected
Rel 33 GLAS Binary Data DS_UTCTime_5


Group: /Data_40HZ

This group contains the 40hz rate data.

Dimension Scales

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
DS_UTCTime_40 DOUBLE
(UNLIMITED)
Transmit Time of First Shot in frame in J2000
(time)
seconds The transmit time of each shot in the 1 second frame measured as 'UTC seconds' elapsed since Jan 1 2000 12:00:00 UTC. This time has been derived from the GPS time accounting for leap seconds. Rel 33 GLAS Binary Data NOT_SET

Group: Data_40HZ/Time

This group contains the 40HZ index and time-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
i_rec_ndx INTEGER
(UNLIMITED)
GLAS Record Index
(NOT_SET)
NOT_SET Unique index that relates this record to the corresponding record(s) in each GLAS data product. Rel 33 GLAS Binary Data DS_UTCTime_40
i_shot_count INTEGER
(UNLIMITED)
GLAS shot counter
(NOT_SET)
NOT_SET Identifies each laser shot within a record index. A combination of i_rec_ndx and i_shot_count can be used to uniquely identify each GLAS laser shot. Rel 33 GLAS Binary Data DS_UTCTime_40

Group: Data_40HZ/Geolocation

This group contains geolocation-related parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
d_lat DOUBLE
(UNLIMITED)
Profile Location, Latitude (at each time)
(latitude)
degrees_north Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 40 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_40
d_lon DOUBLE
(UNLIMITED)
Profile Location, Longitude(at each time)
(longitude)
degrees_east Profile coordinate in the IERS Terrestrial Reference Frame: east longitude and north latitude, at the 40 hertz rate. Rel 33 GLAS Binary Data DS_UTCTime_40

Group: Data_40HZ/FRCloudLayer

This group contains the (40HZ) full resoultion cloud layer parameters.

Label Datatype
(Dimensions)
long_name
(standard_name)
units description source coordinates
r_FRg_grd_sig REAL
(UNLIMITED)
Full Resolution Ground Return Signal at 532 nm
(NOT_SET)
1/(m-sr) Ground return signal from the 532 nm backscatter profile at the height that the ground return is detected. Rel 33 GLAS Binary Data DS_UTCTime_40
r_FRir_grd_sig REAL
(UNLIMITED)
Full Resolution Ground Return Signal at 1064 nm
(NOT_SET)
1/(m-sr) Ground return signal from the 1064 nm backscatter profile at the height that the ground return is detected. Rel 33 GLAS Binary Data DS_UTCTime_40
i_FRir_qaFlag INTEGER_1
(UNLIMITED)
Full Resolution 1064 Quality Flag
(NOT_SET)
NOT_SET Full Resolution 1064 Quality Flag. Value 0 - 12 = Cloud detected by cloud search algorithm with higher numbers indicating a stronger average signal from the region starting at cloud top and extending 500 m below cloud top height. Value 13 = Indicates the possible presence of a cloud based on the value of the integrated signal parameter (i_FRir_intsig) that was not detected directly by the cloud search algorithm. When this occurs, the 40 Hz cloud top height (i_Frir_cldtop) is set to a value of 10.0 km. Value 14 = Indicates the likely presence of low clouds (< 150 m) based on elevated signal from the two bins above the ground return bin that were not detected directly by the cloud search algorithm. When this occurs, the 40 Hz cloud top height (i_Frir_cldtop) is set to a value of 0.10 km. Value 15 = No clouds.

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 cloud_det_0 cloud_det_1 cloud_det_2 cloud_det_3 cloud_det_4 cloud_det_5 cloud_det_6 cloud_det_7 cloud_det_8 cloud_det_9 cloud_det_10 cloud_det_11 cloud_det_12 possible_clouds low_clouds no_clouds
Rel 33 GLAS Binary Data DS_UTCTime_40
i_FRC_af INTEGER_1
(UNLIMITED)
Full Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Availability flag: Tells how many cloud layers were found (from the 532 channel) at this resolution. value 15 = cloud layers were not searched for; value 0 = cloud layers were searched for, but not detected.

flag values flag_meanings
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 not_detected found_1 found_2 found_3 found_4 found_5 found_6 found_7 found_8 found_9 found_10 found_11 found_12 found_13 found_14 not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_40
i_FRC_qf INTEGER_1
(UNLIMITED)
Full Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Quality flag: value 15 = cloud layers were not searched for - either bad data or cloud layers were not found at a coarser resolution; value 1 = low chance of being a cloud; value 2 = moderate; value 3 = high; value 4 = no doubt -- based upon noise-to-signal and geometric thickness evaluation; Value 14 = height of bottom of lowest detected layer in profile very uncertain because ground signal was not detected.

flag values flag_meanings
1, 2, 3, 4, 14, 15 low_chance moderate high no_doubt uncertain not_searched_for
Rel 33 GLAS Binary Data DS_UTCTime_40
i_FRC_df INTEGER_1
(UNLIMITED)
Full Resolution Cloud Layers Flag for 532 nm
(NOT_SET)
NOT_SET Diurnal flag: This tells whether a given layer would be detected during normal daylight conditions. value 0 = layer would not have been detected in typical daytime background; value 1 = layer would have been detected in daylight.

flag values flag_meanings
0, 1 would_not_have_been_detected would_have_been_detected
Rel 33 GLAS Binary Data DS_UTCTime_40
r_FRcld_bot REAL
(UNLIMITED)
Full Resolution Cloud Bottom at 532 nm
(NOT_SET)
meters The height above the reference ellipsoid to the bottom of the full resolution cloud layer (40 Hz). This resolution cloud search is independent of the lower resolution cloud search results and is done for each 40 Hz shot regardless of whether or not clouds were detected at the lower resolutions. Note that the 40 Hz data is available only below 10 km, and thus clouds existing above that level cannot be detected at the 40 Hz resolution. Rel 33 GLAS Binary Data DS_UTCTime_40
r_FRcld_grd REAL
(UNLIMITED)
Full Resolution Cloud Ground Detection at 532 nm
(NOT_SET)
meters The height above the reference ellipsoid of the ground as detected by the full resolution cloud processing algorithms. A value of -127 indicates that the ground was searched for, but not detected. Rel 33 GLAS Binary Data DS_UTCTime_40
r_FRcld_top REAL
(UNLIMITED)
Full Resolution Cloud Top at 532 nm
(NOT_SET)
meters The height above the reference ellipsoid to the top of the full resolution cloud layer (40 Hz). This resolution cloud search is independent of the lower resolution cloud search results and is done for each 40 Hz shot regardless of whether or not clouds were detected at the lower resolutions. Note that the 40 Hz data is available only below 10 km, and thus clouds existing above that level cannot be detected at the 40 Hz resolution. Rel 33 GLAS Binary Data DS_UTCTime_40
r_FRir_cldtop REAL
(UNLIMITED)
Full Resolution 1064 Cloud Top
(NOT_SET)
meters Full resolution (40 Hz) cloud top height obtained from the 1064 atmospheric channel. This parameter is for a 4 second record. Also parameter is in GLA06, 12-15. Rel 33 GLAS Binary Data DS_UTCTime_40
r_FRir_intsig REAL
(UNLIMITED)
Full Resolution 1064 Integrated Signal
(NOT_SET)
1/(m-sr) Though called 'integrated signal' this is actually an average of all bins in the above-ground portion of the 1064 40 Hz profile with values above the threshold of 1.0e-7 (1/(m-sr). This parameter is for a 4 second record. This parameter is also in GLA06, 12-15. Rel 33 GLAS Binary Data DS_UTCTime_40

/ANCILLARY_DATA

/ANCILLARY_DATA

Attribute Example Value
glas_osc_rate 1.000000023
glas_osc_rate_date 2003-10-30
glas_osc_rate_time 00:00:00
sc_osc_rate 0.99999998854809
sc_osc_rate_date 2003-10-30
sc_osc_rate_time 00:00:00
internal_time_delay 0.0000151100
internal_time_delay_date 2003-10-30
internal_time_delay_time 00:00:00
internal_range_delay 9.5560
internal_range_delay_date 2003-10-30
internal_range_delay_time 00:00:00
Additional_Attribute SP_ICE_PATH_NO, SP_ICE_GLAS_StartBlock, SP_ICE_GLAS_EndBlock, ReferenceOrbit, Track, PercentGroundHit, Cycle, Instance
internal_range_delay_desc Internal range calibration bias determined during GLAS instrument integration testing and validated in-flight, meters.
internal_time_delay_desc Internal time calibration bias determined during GLAS instrument integration testing and validated in-flight, seconds.

/METADATA

/METADATA

Attribute Example Value
description This group contains structured, computer-parseable ECHO-style collection and inventory-level metadata.
HDFVersion HDF5 1.8.9
ControlFile cf_name=gla09_test.ctl

/METADATA/COLLECTIONMETADATA

Attribute Example Value
DLLName libDsESDTGlGLASPoly.001Sh.so
GranuleTimeDuration 81280
SpatialSearchType Orbit
DataFileFormat HDF5
ScienceMimeType application/x-hdfeos
BrowseMimeType application/x-hdfeos
BrowseOnlineMimeType image/jpeg
ShortName GLAH09
LongName GLAS/ICESat L2 Global Cloud Heights for Multi-layer Clouds (HDF5)
CollectionDescription The level 2 cloud layer height data with top and bottom heights, and ground heights are provided at a minimum of once per 4 seconds. Data granules will contain approximately 23 hours (14 orbits) of data.
VersionID 33
CitationforExternalPublication The data used in this study were produced by the GLAS Science Team at the ICESat Science Investigator-led Processing System (I-SIPS) at NASA/GSFC. The data archive site is the NSIDC DAAC.
CollectionState In Work
MaintenanceandUpdateFrequency Daily
AccessConstraints Data may not be reproduced or distributed without including the CitationForExternalPublication for this product included in this Metadata. Data may not be distributed in an altered form without the written permission of the GLAS Science Team.
TemporalKeyword Day
SpatialKeyword Global

/METADATA/COLLECTIONMETADATA/AdditionalAttributes

Attribute Example Value
PercentGroundHit AdditionalAttributesContainer
Track AdditionalAttributesContainer
Instrument_State AdditionalAttributesContainer
ReferenceOrbit AdditionalAttributesContainer
SP_ICE_PATH_NO AdditionalAttributesContainer
SP_ICE_GLAS_StartBlock AdditionalAttributesContainer
SP_ICE_GLAS_EndBlock AdditionalAttributesContainer
Cycle AdditionalAttributesContainer
Instance AdditionalAttributesContainer
Instrument_State_Date AdditionalAttributesContainer
Instrument_State_Time AdditionalAttributesContainer
Timing_Bias AdditionalAttributesContainer
Timing_Bias_Date AdditionalAttributesContainer
Timing_Bias_Time AdditionalAttributesContainer
identifier_product_doi AdditionalAttributesContainer
identifier_file_uuid AdditionalAttributesContainer
identifier_product_doi_authority AdditionalAttributesContainer

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Cycle

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription A count of the number of exact repeats of this reference orbit.
AdditionalAttributeName Cycle
ParameterUnitsofMeasurement counts
ParameterRangeBegin 0
ParameterRangeEnd 250

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Instance

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription The number of times that we have returned to a specific reference orbit.
AdditionalAttributeName Instance
ParameterUnitsofMeasurement counts
ParameterRangeBegin 1
ParameterRangeEnd 99

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Instrument_State

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription Flag word that indicates which redundant units (laser, detector, oscillator) of the GLAS instrument are in operation.
AdditionalAttributeName Instrument_State
ParameterUnitsofMeasurement Flag word
ParameterRangeBegin 0
ParameterRangeEnd 5

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Instrument_State_Date

Attribute Example Value
AdditionalAttributeDatatype date
AdditionalAttributeDescription The date that corresponds to the first valid Instrument_State. There is a maximum of two per granule.
AdditionalAttributeName Instrument_State_Date

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Instrument_State_Time

Attribute Example Value
AdditionalAttributeDatatype time
AdditionalAttributeDescription The time that corresponds to the first valid Instrument_State. There is a maximum of two per granule.
AdditionalAttributeName Instrument_State_Time

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/PercentGroundHit

Attribute Example Value
AdditionalAttributeDatatype float
AdditionalAttributeDescription Percent of data for this granule that had a detected ground return of the transmitted laser pulse.
AdditionalAttributeName PercentGroundHit
ParameterUnitsofMeasurement Percent
ParameterRangeBegin 0.0
ParameterRangeEnd 100.0
ParameterValueAccuracy 1
ParameterMeasurementResolution 1

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/ReferenceOrbit

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription Assigned number for which exact orbital elements describe the exact repeat orbit pattern.
AdditionalAttributeName ReferenceOrbit
ParameterUnitsofMeasurement Assigned number
ParameterRangeBegin 1
ParameterRangeEnd 30000

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/SP_ICE_GLAS_EndBlock

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription Integer number within GLAS coverage scheme in which granule data ends.
AdditionalAttributeName SP_ICE_GLAS_EndBlock
ParameterRangeBegin 1
ParameterRangeEnd 360

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/SP_ICE_GLAS_StartBlock

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription Integer number within GLAS coverage scheme in which granule data starts.
AdditionalAttributeName SP_ICE_GLAS_StartBlock
ParameterRangeBegin 1
ParameterRangeEnd 360

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/SP_ICE_PATH_NO

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription Number which represents the GLAS path number.
AdditionalAttributeName SP_ICE_PATH_NO
ParameterRangeBegin 1
ParameterRangeEnd 32768

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Timing_Bias

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription 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.
AdditionalAttributeName Timing_Bias
ParameterUnitsofMeasurement Microseconds
ParameterRangeBegin -1000000
ParameterRangeEnd +1000000

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Timing_Bias_Date

Attribute Example Value
AdditionalAttributeDatatype date
AdditionalAttributeDescription The date that corresponds to the first valid Timing_Bias. There are a maximum of two per granule.
AdditionalAttributeName Timing_Bias_Date

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Timing_Bias_Time

Attribute Example Value
AdditionalAttributeDatatype time
AdditionalAttributeDescription The time that corresponds to the first valid Timing_Bias. There are a maximum of two per granule.
AdditionalAttributeName Timing_Bias_Time

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/Track

Attribute Example Value
AdditionalAttributeDatatype int
AdditionalAttributeDescription The unique number assigned for each repeat ground track (one orbit) of the reference orbit.
AdditionalAttributeName Track
ParameterUnitsofMeasurement counts
ParameterRangeBegin 0
ParameterRangeEnd 3000

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/identifier_file_uuid

Attribute Example Value
AdditionalAttributeDatatype varchar
AdditionalAttributeDescription Universally unique identifier for this data product's files
AdditionalAttributeName identifier_file_uuid

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/identifier_product_doi

Attribute Example Value
AdditionalAttributeDatatype varchar
AdditionalAttributeDescription Digital object identifier that uniquely identifies this data product
AdditionalAttributeName identifier_product_doi

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/identifier_product_doi/InformationContent

Attribute Example Value
ParameterValue 10.5067/ICESAT/GLAS/DATA202

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/identifier_product_doi_authority

Attribute Example Value
AdditionalAttributeDatatype varchar
AdditionalAttributeDescription URL of the digital object identifier resolving authority
AdditionalAttributeName identifier_product_doi_authority

/METADATA/COLLECTIONMETADATA/AdditionalAttributes/identifier_product_doi_authority/InformationContent

Attribute Example Value
ParameterValue http://dx.doi.org

/METADATA/COLLECTIONMETADATA/CSDTDescription

Attribute Example Value
PrimaryCSDT n-Dim Array of Records
IndirectReference tracks/orbits
Implementation HDF
CSDTComments Granule contains fourteen orbits of data; nominally 24-hour period.

/METADATA/COLLECTIONMETADATA/CollectionAssociation

Attribute Example Value
GLA00 CollectionAssociationContainer
GLAH02 CollectionAssociationContainer
GLAH07 CollectionAssociationContainer
GLAH08 CollectionAssociationContainer
GLAH10 CollectionAssociationContainer
GLAH11 CollectionAssociationContainer

/METADATA/COLLECTIONMETADATA/CollectionAssociation/GLA00

Attribute Example Value
CollectionType Science Associated
CollectionUse The initial collection of GLAS instrument data downlinked from the spacecraft.
ShortName GLA00
VersionID 1

/METADATA/COLLECTIONMETADATA/CollectionAssociation/GLAH02

Attribute Example Value
CollectionType Science Associated
CollectionUse Level 1A atmospheric data product file containing: normalized lidar signals.
ShortName GLAH02
VersionID 33

/METADATA/COLLECTIONMETADATA/CollectionAssociation/GLAH07

Attribute Example Value
CollectionType Input
CollectionUse Level 1B file containing: calibrated backscatter profiles.
ShortName GLAH07
VersionID 33

/METADATA/COLLECTIONMETADATA/CollectionAssociation/GLAH08

Attribute Example Value
CollectionType Dependent
CollectionUse Level 2 file containing: planetary boundary layer heights and aerosol layer top and bottom.
ShortName GLAH08
VersionID 33

/METADATA/COLLECTIONMETADATA/CollectionAssociation/GLAH10

Attribute Example Value
CollectionType Dependent
CollectionUse Level 2 file containing: cloud- and aerosol- attenuation corrected backscatter and extinction profiles.
ShortName GLAH10
VersionID 33

/METADATA/COLLECTIONMETADATA/CollectionAssociation/GLAH11

Attribute Example Value
CollectionType Dependent
CollectionUse Level 2 file containing: cloud and aerosol layer optical depths.
ShortName GLAH11
VersionID 33

/METADATA/COLLECTIONMETADATA/ContactOrganization

Attribute Example Value
Data_Originator ContactOrganizationContainer
Archive ContactOrganizationContainer

/METADATA/COLLECTIONMETADATA/ContactOrganization/Archive

Attribute Example Value
Role Archive
HoursofService M-F, 8:00am to 5:00pm, Mountain Time
ContactInstructions For inquiries, contact NSIDC User Services. Primary first level contact.
ContactOrganizationName NSIDC User Services
StreetAddress CIRES/NSIDC University of Colorado Campus, Box 449
City Boulder
StateProvince Colorado
PostalCode 80309-0449
Country USA
TelephoneNumber 303-492-2468
TelephoneNumberType Facsimile
ElectronicMailAddress nsidc@nsidc.org

/METADATA/COLLECTIONMETADATA/ContactOrganization/Data_Originator

Attribute Example Value
Role Data Originator
HoursofService M-F, 8:00am to 4:30pm Eastern Time
ContactInstructions Contact by e-mail first
ContactOrganizationName ICESat Science Investigator-led Processing System (I-SIPS)
StreetAddress Building 33, NASA Goddard Space Flight Center
City Greenbelt
StateProvince Maryland
PostalCode 20771
Country USA
TelephoneNumber 757-864-1238
TelephoneNumberType Voice
ElectronicMailAddress David.W.Hancock@nasa.gov

/METADATA/COLLECTIONMETADATA/ContactPerson

Attribute Example Value
Hancock ContactPersonContainer
Schutz ContactPersonContainer
Zwally ContactPersonContainer
DiMarzio ContactPersonContainer

/METADATA/COLLECTIONMETADATA/ContactPerson/DiMarzio

Attribute Example Value
Role Producer
HoursofService M-F, 8:00am to 4:30pm Eastern Time
ContactInstructions None
ContactJobPosition Deputy Science Software Development Manager
ContactFirstName John
ContactMiddleName P
ContactLastName DiMarzio
StreetAddress Building 33, Rm. B-209D, NASA/GSFC
City Greenbelt
StateProvince Maryland
PostalCode 20771
Country USA
TelephoneNumber 301-614-5893
TelephoneNumberType Voice
ElectronicMailAddress John.P.Dimarzio.1@nasa.gov

/METADATA/COLLECTIONMETADATA/ContactPerson/Hancock

Attribute Example Value
Role Data Originator
HoursofService M-F, 8:00am to 4:30pm. Eastern Time.
ContactInstructions None
ContactJobPosition Science Software Development Manager.
ContactFirstName David
ContactMiddleName W.
ContactLastName Hancock
StreetAddress Building N-159, NASA/GSFC Wallops Flight Facility.
City Wallops Island
StateProvince Virginia
PostalCode 23337
Country USA
TelephoneNumber 757-824-1238
TelephoneNumberType Voice
ElectronicMailAddress David.W.Hancock@nasa.gov

/METADATA/COLLECTIONMETADATA/ContactPerson/Schutz

Attribute Example Value
Role Investigator
HoursofService M-F, 8:00am to 4:30pm Central Time
ContactInstructions None
ContactJobPosition GLAS Science Team Leader
ContactFirstName Bob
ContactMiddleName E
ContactLastName Schutz
StreetAddress 3925 W. Braker Lane, Center for Space Research
City Austin
StateProvince Texas
PostalCode 78759-5321
Country USA
TelephoneNumber 512-471-4267
TelephoneNumberType Voice
ElectronicMailAddress schutz@utcsr.ae.utexas.edu

/METADATA/COLLECTIONMETADATA/ContactPerson/Zwally

Attribute Example Value
Role Producer
HoursofService M-F, 8:00am to 4:30pm Eastern Time
ContactInstructions None.
ContactJobPosition ICESat Project Scientist
ContactFirstName Jay
ContactLastName Zwally
StreetAddress Building 33, Rm A-217
City Greenbelt
StateProvince Maryland
PostalCode 20771
Country USA
TelephoneNumber 301-614-5643
TelephoneNumberType Voice
ElectronicMailAddress Jay.Zwally@nasa.gov

/METADATA/COLLECTIONMETADATA/DisciplineTopicParameters

Attribute Example Value
Atmosphere DisciplineTopicParametersContainer

/METADATA/COLLECTIONMETADATA/DisciplineTopicParameters/Atmosphere

Attribute Example Value
ECSDisciplineKeyword Earth Science
ECSTopicKeyword Atmosphere
ECSTermKeyword Clouds
ECSVariableKeyword Cloud Vertical Distribution

/METADATA/COLLECTIONMETADATA/DisciplineTopicParameters/Atmosphere/ECSParameter

Attribute Example Value
ECSParameterKeyword Cloud Layer Heights

/METADATA/COLLECTIONMETADATA/ECSCollection

Attribute Example Value
RevisionDate 2012-06-25
SuggestedUsage GLAH09 contains the cloud layer heights for researchers. Cloud layer height data consist of top and bottom heights for up to 10 layers below 20 km at 0.25 hz and 5 hz (40hz for below 4 km). Ground heights are provided at each resolution. Each GLAH09 file was created from an equivalent GLA09 binary file. The data used to create the GLAH09 values are contained in the equivalent GLAHxx files for the GLAxx files. See the provenance metadata for the creation of the GLA09.
ProcessingCenter GSFC I-SIPS
ArchiveCenter NSIDC
VersionDescription Initial Version
DatasetDisclaimerPointer http://nsidc.org/data/icesat/disclaimer.html
ECSCollectionGuidePointer http://nsidc.org/data/docs/daac/glas_icesat_l1_l2_global_atmosphere.gd.html
ECSCollectionGuidePointerComment Guide Document for this product at NSIDC
MiscellaneousInformationPointer http://nsidc.org/daac/icesat/index.html
MiscellaneousInformationPointerComment GLAS Product page at NSIDC

/METADATA/COLLECTIONMETADATA/Platform

Attribute Example Value
ICESat PlatformContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat

Attribute Example Value
PlatformShortName ICESat
PlatformLongName Ice, Cloud, and Land Elevation Satellite
PlatformType Spacecraft

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument

Attribute Example Value
GLAS InstrumentContainer
GPS InstrumentContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS

Attribute Example Value
InstrumentShortName GLAS
InstrumentLongName Geoscience Laser Altimeter System
InstrumentTechnique Laser Altimetry and Light Detection and Radar
NumberofSensors 3

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/InstrumentCharacteristic

Attribute Example Value
SwathWidth InstrumentCharacteristicContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/InstrumentCharacteristic/SwathWidth

Attribute Example Value
InstrumentCharacteristicName SwathWidth
InstrumentCharacteristicDescription The width of the sensor scan as the satellite moves along the ground track.
InstrumentCharacteristicDataType int
InstrumentCharacteristicUnit kilometers
InstrumentCharacteristicValue 2

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor

Attribute Example Value
LA SensorContainer
PC SensorContainer
CD SensorContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/CD

Attribute Example Value
SensorShortName CD
SensorLongName Cloud LIDAR
SensorTechnique Measure of 1064nm return energy in 75m bins from 20km to surface

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/CD/SensorCharacteristic

Attribute Example Value
wavelength SensorCharacteristicContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/CD/SensorCharacteristic/wavelength

Attribute Example Value
SensorCharacteristicName wavelength
SensorCharacteristicDescription detector
SensorCharacteristicDataType varchar
SensorCharacteristicUnit nanometer
SensorCharacteristicValue 1064 nm

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/LA

Attribute Example Value
SensorShortName LA
SensorLongName Laser Altimeter
SensorTechnique Exact Measurement of Time between Transmit Pulse and receive ground return

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/LA/SensorCharacteristic

Attribute Example Value
wavelength SensorCharacteristicContainer
waveform SensorCharacteristicContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/LA/SensorCharacteristic/waveform

Attribute Example Value
SensorCharacteristicName waveform
SensorCharacteristicDescription digitizer
SensorCharacteristicDataType varchar
SensorCharacteristicUnit counts
SensorCharacteristicValue 0-255

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/LA/SensorCharacteristic/wavelength

Attribute Example Value
SensorCharacteristicName wavelength
SensorCharacteristicDescription transmission
SensorCharacteristicDataType varchar
SensorCharacteristicUnit nanometer
SensorCharacteristicValue 1064 nm

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/PC

Attribute Example Value
SensorShortName PC
SensorLongName Photon Counter for the 532 nm Aerosol Returns
SensorTechnique Counting of 532nm photon return in 75m bins 40km to surface

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/PC/SensorCharacteristic

Attribute Example Value
wavelength SensorCharacteristicContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GLAS/Sensor/PC/SensorCharacteristic/wavelength

Attribute Example Value
SensorCharacteristicName wavelength
SensorCharacteristicDescription detector
SensorCharacteristicDataType varchar
SensorCharacteristicUnit nanometer
SensorCharacteristicValue 532nm

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GPS

Attribute Example Value
InstrumentShortName GPS
InstrumentLongName Global Positioning System Receiver
InstrumentTechnique Radionavigation
NumberofSensors 1

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GPS/Sensor

Attribute Example Value
GPS_Receiver SensorContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/Instrument/GPS/Sensor/GPS_Receiver

Attribute Example Value
SensorShortName GPS Receiver
SensorLongName Dual frequency GPS receiver
SensorTechnique Pseudorange and carrier phase

/METADATA/COLLECTIONMETADATA/Platform/ICESat/PlatformCharacteristic

Attribute Example Value
OrbitInclination PlatformCharacteristicContainer
OrbitalPeriod PlatformCharacteristicContainer

/METADATA/COLLECTIONMETADATA/Platform/ICESat/PlatformCharacteristic/OrbitInclination

Attribute Example Value
PlatformCharacteristicName OrbitInclination
PlatformCharacteristicDescription Angle between the orbit plane and the Earth's equatorial plane
PlatformCharacteristicDataType float
PlatformCharacteristicUnit Degrees
PlatformCharacteristicValue 94.0

/METADATA/COLLECTIONMETADATA/Platform/ICESat/PlatformCharacteristic/OrbitalPeriod

Attribute Example Value
PlatformCharacteristicName OrbitalPeriod
PlatformCharacteristicDescription Orbital period in decimal minutes.
PlatformCharacteristicDataType float
PlatformCharacteristicUnit Minutes
PlatformCharacteristicValue 96.7

/METADATA/COLLECTIONMETADATA/ProcessingLevel

Attribute Example Value
ProcessingLevelDescription Geophysical Quantities at the sensor resolution or geolocated
ProcessingLevelID 2

/METADATA/COLLECTIONMETADATA/Review

Attribute Example Value
ScienceReviewDate 2001-03-04
ScienceReviewStatus QA at DAACs
FutureReviewDate 2001-09-04

/METADATA/COLLECTIONMETADATA/Spatial

Attribute Example Value
SpatialCoverageType Horizontal
WestBoundingCoordinate -180.0
NorthBoundingCoordinate 90.0
EastBoundingCoordinate 180.0
SouthBoundingCoordinate -90.0

/METADATA/COLLECTIONMETADATA/StorageMediumClass

Attribute Example Value
StorageMedium Online

/METADATA/COLLECTIONMETADATA/Temporal

Attribute Example Value
TimeType UTC
DateType J2000
TemporalRangeType Continuous Range
PrecisionofSeconds 2
EndsatPresentFlag Y
RangeBeginningDate 2003-01-13
RangeBeginningTime 00:00:00
RangeEndingDate 2010-01-13
RangeEndingTime 00:00:00

/METADATA/INVENTORYMETADATA

Attribute Example Value
PGEVersion Version 1.1
ShortName GLAH09
VersionID 33
RangeBeginningTime 01:51:38
RangeEndingTime 00:24:45
RangeBeginningDate 2003-11-18
RangeEndingDate 2003-11-19

/METADATA/INVENTORYMETADATA/ECSDataGranule

Attribute Example Value
ReprocessingPlanned no further update anticipated
ReprocessingActual reprocessed
LocalGranuleID GLAH09_633_2103_002_0407_0_01_0001.H5
ProductionDateTime 2013-02-08T11:58:44
LocalVersionID 33

/METADATA/INVENTORYMETADATA/InputGranule

Attribute Example Value
InputPointer gla09_test.ctl, tai-utc.dat, GLA09_633_2103_002_0407_0_01_0001.P0310, DsESDTGlGLAH09.033.desc

/METADATA/INVENTORYMETADATA/MeasuredParameter

Attribute Example Value
ParameterName 532_Cloud_Layer_Heights, 1064_Cloud_Layer_Heights

/METADATA/INVENTORYMETADATA/OrbitCalculatedSpatialDomain

Attribute Example Value
OrbitNumber 4604, 4605, 4606, 4607, 4608, 4609, 4610, 4611, 4612, 4613, 4614, 4615, 4616, 4617, 4618
StartOrbitNumber 4604
StopOrbitNumber 4618
EquatorCrossingLongitude -103.22287, -127.41792, -151.61336, -175.8089, 159.99582, 135.80128, 111.6064, 87.41001, 63.21418, 39.01927, 14.825027, -9.368591, -33.562866, -57.758118, -81.95212
EquatorCrossingTime 01:38:10, 03:14:50, 04:51:29, 06:28:07, 08:04:46, 09:41:25, 11:18:05, 12:54:44, 14:31:22, 16:08:02, 17:44:42, 19:21:21, 20:58:00, 22:34:38, 00:11:17
EquatorCrossingDate 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-18, 2003-11-19

/METADATA/INVENTORYMETADATA/ProductSpecificMetadata

Attribute Example Value
PercentGroundHit 0
Track 407, 408, 409, 410, 411, 412, 413, 414, 415, 416, 417, 418, 419, 420, 421
Instrument_State 373338
ReferenceOrbit 1
SP_ICE_PATH_NO 3429, 3430, 3431, 3432, 3433, 3434, 3435, 3436, 3437, 3438, 3439, 3440, 3441, 3442, 3443
SP_ICE_GLAS_StartBlock NOT SET
SP_ICE_GLAS_EndBlock NOT SET
Cycle 2
Instance 3
Instrument_State_Date 2003-10-30
Instrument_State_Time 00:00:00
identifier_product_doi 10.5067/ICESAT/GLAS/DATA202
identifier_file_uuid 599740C3-F062-4F49-A756-8A0DA37BC95B
identifier_product_doi_authority http://dx.doi.org

/METADATA/PROVENANCE

/METADATA/PROVENANCE/STEP_1

Attribute Example Value
ProcessDateTime 2011-06-20T15:27:20

/METADATA/PROVENANCE/STEP_1/ProcessAgent

Attribute Example Value
Name glas_atm
Type 2
Version 6.0.1
Description This process is an instantiation of the GLAS Science Algorithm Software (GSAS) 2 ATBDs.

/METADATA/PROVENANCE/STEP_1/ProcessInput

Attribute Example Value
Name GLA02_033_2103_002_0407_0_02_0001.DAT, GLA02_033_2103_002_0409_0_02_0001.DAT, GLA02_033_2103_002_0411_0_02_0001.DAT, GLA02_033_2103_002_0413_0_02_0001.DAT, GLA02_033_2103_002_0415_0_02_0001.DAT, GLA02_033_2103_002_0417_0_02_0001.DAT, GLA02_033_2103_002_0419_0_02_0001.DAT, GLA05_633_2103_002_0407_1_01_0001.DAT, GLA05_633_2103_002_0407_2_01_0001.DAT, GLA05_633_2103_002_0407_3_01_0001.DAT, GLA05_633_2103_002_0407_4_01_0001.DAT, GLA05_633_2103_002_0408_1_01_0001.DAT, GLA05_633_2103_002_0408_2_01_0001.DAT, GLA05_633_2103_002_0408_3_01_0001.DAT, GLA05_633_2103_002_0408_4_01_0001.DAT, GLA05_633_2103_002_0409_1_01_0001.DAT, GLA05_633_2103_002_0409_2_01_0001.DAT, GLA05_633_2103_002_0409_3_01_0001.DAT, GLA05_633_2103_002_0409_4_01_0001.DAT, GLA05_633_2103_002_0410_1_01_0001.DAT, GLA05_633_2103_002_0410_2_01_0001.DAT, GLA05_633_2103_002_0410_3_01_0001.DAT, GLA05_633_2103_002_0410_4_01_0001.DAT, GLA05_633_2103_002_0411_1_01_0001.DAT, GLA05_633_2103_002_0411_2_01_0001.DAT, GLA05_633_2103_002_0411_3_01_0001.DAT, GLA05_633_2103_002_0411_4_01_0001.DAT, GLA05_633_2103_002_0412_1_01_0001.DAT, GLA05_633_2103_002_0412_2_01_0001.DAT, GLA05_633_2103_002_0412_3_01_0001.DAT, GLA05_633_2103_002_0412_4_01_0001.DAT, GLA05_633_2103_002_0413_1_01_0001.DAT, GLA05_633_2103_002_0413_2_01_0001.DAT, GLA05_633_2103_002_0413_3_01_0001.DAT, GLA05_633_2103_002_0413_4_01_0001.DAT, GLA05_633_2103_002_0414_1_01_0001.DAT, GLA05_633_2103_002_0414_2_01_0001.DAT, GLA05_633_2103_002_0414_3_01_0001.DAT, GLA05_633_2103_002_0414_4_01_0001.DAT, GLA05_633_2103_002_0415_1_01_0001.DAT, GLA05_633_2103_002_0415_2_01_0001.DAT, GLA05_633_2103_002_0415_3_01_0001.DAT, GLA05_633_2103_002_0415_4_01_0001.DAT, GLA05_633_2103_002_0416_1_01_0001.DAT, GLA05_633_2103_002_0416_2_01_0001.DAT, GLA05_633_2103_002_0416_3_01_0001.DAT, GLA05_633_2103_002_0416_4_01_0001.DAT, GLA05_633_2103_002_0417_1_01_0001.DAT, GLA05_633_2103_002_0417_2_01_0001.DAT, GLA05_633_2103_002_0417_3_01_0001.DAT, GLA05_633_2103_002_0417_4_01_0001.DAT, GLA05_633_2103_002_0418_1_01_0001.DAT, GLA05_633_2103_002_0418_2_01_0001.DAT, GLA05_633_2103_002_0418_3_01_0001.DAT, GLA05_633_2103_002_0418_4_01_0001.DAT, GLA05_633_2103_002_0419_1_01_0001.DAT, GLA05_633_2103_002_0419_2_01_0001.DAT, GLA05_633_2103_002_0419_3_01_0001.DAT, GLA05_633_2103_002_0419_4_01_0001.DAT, GLA05_633_2103_002_0420_1_01_0001.DAT, GLA05_633_2103_002_0420_2_01_0001.DAT, GLA05_633_2103_002_0420_3_01_0001.DAT, GLA05_633_2103_002_0420_4_01_0001.DAT, ANC01_006_20031117_180000_01_0000.DAT, ANC01_006_20031118_000000_01_0000.DAT, ANC01_006_20031118_060000_01_0000.DAT, ANC01_006_20031118_120000_01_0000.DAT, ANC01_006_20031118_180000_01_0000.DAT, ANC01_006_20031119_000000_01_0000.DAT, ANC01_006_20031117_180000_01_0002.DAT, ANC01_006_20031118_000000_01_0002.DAT, ANC01_006_20031118_060000_01_0002.DAT, ANC01_006_20031118_120000_01_0002.DAT, ANC01_006_20031118_180000_01_0002.DAT, ANC01_006_20031119_000000_01_0002.DAT, ANC01_006_20031117_180000_01_0003.DAT, ANC01_006_20031118_000000_01_0003.DAT, ANC01_006_20031118_060000_01_0003.DAT, ANC01_006_20031118_120000_01_0003.DAT, ANC01_006_20031118_180000_01_0003.DAT, ANC01_006_20031119_000000_01_0003.DAT, ANC01_006_20031117_180000_01_0004.DAT, ANC01_006_20031118_000000_01_0004.DAT, ANC01_006_20031118_060000_01_0004.DAT, ANC01_006_20031118_120000_01_0004.DAT, ANC01_006_20031118_180000_01_0004.DAT, ANC01_006_20031119_000000_01_0004.DAT, ANC01_006_20031117_180000_01_0001.DAT, ANC01_006_20031118_000000_01_0001.DAT, ANC01_006_20031118_060000_01_0001.DAT, ANC01_006_20031118_120000_01_0001.DAT, ANC01_006_20031118_180000_01_0001.DAT, ANC01_006_20031119_000000_01_0001.DAT, ANC01_006_20031117_180000_01_0005.DAT, ANC01_006_20031118_000000_01_0005.DAT, ANC01_006_20031118_060000_01_0005.DAT, ANC01_006_20031118_120000_01_0005.DAT, ANC01_006_20031118_180000_01_0005.DAT, ANC01_006_20031119_000000_01_0005.DAT, ANC01_006_20031117_180000_01_0006.DAT, ANC01_006_20031118_000000_01_0006.DAT, ANC01_006_20031118_060000_01_0006.DAT, ANC01_006_20031118_120000_01_0006.DAT, ANC01_006_20031118_180000_01_0006.DAT, ANC01_006_20031119_000000_01_0006.DAT,
Type GLA02, GLA02, GLA02, GLA02, GLA02, GLA02, GLA02, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, GLA05, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC01, ANC04, ANC04, anc07, anc07, anc07, anc07, anc07, anc07, anc07, ANC08, ANC08, ANC09, ANC09, anc12, anc12, anc13, anc18, anc25, anc27, anc27, anc30, anc31, ANC33, anc35, ANC36, ANC36, ANC36, ANC36, ANC36, ANC36, ANC36, anc38, anc38, anc38, anc38, anc41, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45, anc45
Version 033, 033, 033, 033, 033, 033, 033, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 633, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 006, 007, 007, 033, 033, 033, 033, 033, 033, 033, 015, 015, 076, 076, 004, 004, 006, 001, 005, 001, 001, 004, 004, 001, 001, 033, 033, 033, 033, 033, 033, 033, 005, 005, 005, 005, 009, 033, 033, 033, 033, 033, 033, 033, 033, 033, 033, 033, 033, 033, 033, 033

/METADATA/PROVENANCE/STEP_1/ProcessOutput

Attribute Example Value
Name GLA09_633_2103_002_0407_0_01_0001.DAT
Type GLA09
Version 633

/METADATA/PROVENANCE/STEP_2

Attribute Example Value
ProcessDateTime 2013-02-08T11:58:44.000000Z

/METADATA/PROVENANCE/STEP_2/ProcessAgent

Attribute Example Value
Name GLA09_h5_convert
Type Data_Reformat
Version Version 1.1 (February 2013)
Description GLA09 Conversion PGE

/METADATA/PROVENANCE/STEP_2/ProcessInput

Attribute Example Value
Name ./gla09_test.ctl, ../../data/tai-utc.dat, in/GLA09_633_2103_002_0407_0_01_0001.P0310, ../../glas_hdf/data/esdts/DsESDTGlGLAH09.033.desc
Type IN_CNTL, IN_ANC_TAIUTC, IN_GLA09, IN_ESDT
Version 0, 0, 1, 1

/METADATA/PROVENANCE/STEP_2/ProcessOutput

Attribute Example Value
Name out/GLAH09_633_2103_002_0407_0_01_0001.H5
Type OUT_GLAH09
Version 1
UUID 599740C3-F062-4F49-A756-8A0DA37BC95B
DOI 10.5067/ICESAT/GLAS/DATA202

Page last updated: 02/21/2013