GEDI02_B v001

GEDI L2B Canopy Cover and Vertical Profile Metrics Data Global Footprint Level


PI: Ralph Dubayah

Spatial querying of GEDI files is now available with the GEDI Finder web service. Additional information can be found in the GEDI Finder User Guide.

Description

The Global Ecosystem Dynamics Investigation (GEDI) mission aims to characterize ecosystem structure and dynamics to enable radically improved quantification and understanding of the Earth’s carbon cycle and biodiversity. The GEDI instrument produces high resolution laser ranging observations of the 3-dimensional structure of the Earth. GEDI is attached to the International Space Station and collects data globally between 51.6° N and 51.6° S latitudes at the highest resolution and densest sampling of any light detection and ranging (lidar) instrument in orbit to date.

The purpose of the GEDI Level 2B Canopy Cover and Vertical Profile Metrics product (GEDI02_B) is to extract biophysical metrics from each GEDI waveform. These metrics are based on the directional gap probability profile derived from the L1B waveform. Metrics provided include canopy cover, Plant Area Index (PAI), Plant Area Volume Density (PAVD), and Foliage Height Diversity (FHD). The GEDI02_B product is provided in HDF-5 format and has a spatial resolution (average footprint) of 25 meters.

The GEDI02_B data product contains 96 layers for each of the eight-beam ground transects (or laser footprints located on the land surface). Datasets provided include precise latitude, longitude, elevation, height, canopy cover, and vertical profile metrics. Additional information for the layers can be found in the GEDI Level 2B Data Dictionary.

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Characteristics

Collection and Granule

Collection

Characteristic Description
CollectionGEDI
DOI10.5067/GEDI/GEDI02_B.001
File Size~7 GB
Temporal ResolutionVaries
Temporal Extent2019-03-25 to Present
Spatial ExtentGlobal (51.6 °N to 51.6 °S Latitude)
Coordinate SystemGeographic Latitude and Longitude
DatumWGS84/EGM96
File FormatHDF5
Geographic Dimensions4.2 km across-track by one full ISS orbit along-track

Granule

Characteristic Description
Number of Science Dataset (SDS) Layers96
Columns/RowsN/A
Pixel Size25 m

Layers

SDS Name Description Units Data Type Fill Value No Data Value Valid Range Scale Factor
algorithmrun_flag The L2B algorithm is run if this flag is set to 1 indicating data have sufficient waveform fidelity for L2B to run N/A 8-bit unsigned integer N/A N/A 0, 1 N/A
beam Beam number Number 16-bit unsigned integer N/A N/A 0 to 11 N/A
channel Channel number Number 8-bit unsigned integer N/A N/A 0 to 7 N/A
cover Total canopy cover Percent 32-bit floating point -9999 N/A 0, 1 N/A
cover_z Cumulative canopy cover vertical profile Percent 32-bit floating point -9999 N/A 0, 1 N/A
fhd_normal Foliage Height Diversity N/A 32-bit floating point -9999 N/A N/A N/A
master_frac Master time fractional seconds Seconds 64-bit floating point N/A N/A N/A N/A
master_int Master time integer seconds Seconds 32-bit unsigned integer N/A N/A N/A N/A
num_detectedmodes Number of detected modes in received (RX) waveform Number 8-bit unsigned integer N/A N/A N/A N/A
omega Foliage Clumping Index N/A 32-bit floating point N/A N/A 0, 1 N/A
pai Total Plant Area Index m²/m² 32-bit floating point -9999 N/A N/A N/A
pai_z Plant Area Index profile m²/m² 32-bit floating point -9999 N/A N/A N/A
pavd_z Plant Area Volume Density profile m²/m³ 32-bit floating point -9999 N/A N/A N/A
pgap_theta Total Gap Probability (theta) N/A 32-bit floating point -9999 N/A 0, 1 N/A
pgap_theta_error Total Pgap (theta) error N/A 32-bit floating point -9999 N/A 0, 1 N/A
pgap_theta_z Directional gap probability profile N/A 32-bit floating point -9999 N/A 0 to 10000 N/A
l2a_quality_flag L2A quality flag Quality Flag 8-bit unsigned integer N/A N/A 0, 1 N/A
l2b_quality_flag L2B quality flag Quality Flag 8-bit unsigned integer N/A N/A 0, 1 N/A
rg Integral of the ground component in the RX waveform for the selected L2A processing version Number 32-bit floating point -9999 N/A N/A N/A
rh100 Height above ground of the received waveform signal start (rh[101] from L2A) cm 16-bit signed integer N/A N/A -21300 to 21300 N/A
rhog Volumetric scattering coefficient (rho) of the ground Number 32-bit floating point -9999 N/A N/A N/A
rhog_error Rho (ground) error Number 32-bit floating point -9999 N/A N/A N/A
rhov Volumetric scattering coefficient (rho) of the canopy Number 32-bit floating point -9999 N/A N/A N/A
rhov_error Rho (canopy) error Number 32-bit floating point -9999 N/A N/A N/A
rossg Ross-G function N/A 32-bit floating point -9999 N/A 0, 1 N/A
rv Integral of the vegetation component in the RX waveform for the selected L2A processing version Number 32-bit floating point -9999 N/A N/A N/A
rx_range_highestreturn Range to signal start Meters 64-bit floating point -9999 N/A N/A N/A
rx_sample_count Received sample count Number 64-bit signed integer N/A N/A N/A N/A
rx_sample_start_index Received sample start index Number 64-bit signed integer N/A N/A N/A N/A
selected_l2a_algorithm Selected L2A algorithm setting N/A 8-bit unsigned integer N/A N/A 1 to 6 N/A
selected_rg_algorithm Selected R (ground) algorithm N/A 8-bit unsigned integer N/A N/A N/A N/A
sensitivity Maxmimum canopy cover that can be penetrated N/A 32-bit floating point N/A N/A 0, 1 N/A
shot_number Shot number Number 64-bit unsigned integer N/A N/A N/A N/A
stale_return_flag Stale return flag Class Flag 8-bit unsigned integer N/A N/A 0, 1 N/A
surface_flag Surface flag indicating elevation of lowest mode Class Flag 8-bit unsigned integer N/A N/A 0, 1 N/A
dz Vertical step size of foliage profile Meters 64-bit floating point N/A N/A N/A N/A
l2a_alg_count Number of candidate algorithms available in the corresponding GEDI L2A data product Number 64-bit signed integer N/A N/A N/A N/A
maxheight_cuttoff The maximum height above ground value used for foliage profile calculation Meters 64-bit floating point N/A N/A 0 to 150 N/A
rg_eg_constraint_center_buffer Buffer size used to constrain the center parameter in the exponentially modified Gaussian fit to R (ground) Nanoseconds 32-bit signed integer N/A N/A N/A N/A
rg_eg_mpfit_max_func_evals MPFIT maximum number of function evaluations N/A 16-bit unsigned integer N/A N/A N/A N/A
rg_eg_mpfit_maxiters MPFIT maximum number of iterations N/A 16-bit unsigned integer N/A N/A N/A N/A
rg_eg_mpfit_tolerance MPFIT convergence criterium N/A 64-bit floating point N/A N/A N/A N/A
signal_search_buff Buffer size used to extend above toploc and below botloc Nanoseconds 64-bit floating point N/A N/A 0 to 255 N/A
tx_noise_stddev_multiplier Multiplier on the transmit waveform noise standard deviation used R (ground) estimation N/A 64-bit floating point N/A N/A 0 to 255 N/A
degrade_flag Degrade flag is set to greater than zero if the shot occurs during a degrade period, zero otherwise Class Flag 8-bit signed integer N/A N/A 0, 1 N/A
delta_time Transmit time of the shot, measured in seconds from the master_time_epoch since 2018-01-01 Seconds 64-bit floating point N/A N/A N/A N/A
digital_elevation_model Digital elevation model height above the WGS84 ellipsoid Meters 32-bit floating point -999999.0 N/A -962 to 10038 N/A
elev_highestreturn Elevation of highest detected return relative to reference ellipsoid Meters 32-bit floating point N/A N/A -1000 to 25000 N/A
elev_lowestmode Elevation of center of lowest mode relative to reference ellipsoid Meters 32-bit floating point N/A N/A -1000 to 25000 N/A
elevation_bin0 Elevation of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate Meters 64-bit floating point -9999 N/A N/A N/A
elevation_bin0_error Error in elevation of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate Meters 32-bit floating point -9999 N/A N/A N/A
elevation_lastbin Elevation of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate Meters 64-bit floating point -9999 N/A N/A N/A
elevation_lastbin_error Error in elevation of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate Meters 32-bit floating point -9999 N/A N/A N/A
height_bin0 Height of the first bin of the pgap_theta_z, relative to the ground Meters 32-bit floating point -9999 N/A N/A N/A
height_lastbin Height of the last bin of the pgap_theta_z, relative to the ground Meters 32-bit floating point -9999 N/A N/A N/A
lat_highestreturn Latitude of highest detected return Degree 64-bit floating point N/A N/A -55 to 55 N/A
lat_lowestmode Latitude of center of lowest mode Degree 64-bit floating point N/A N/A -55 to 55 N/A
latitude_bin0 Latitude of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 64-bit floating point -9999 N/A N/A N/A
latitude_bin0_error Error in latitude of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 32-bit floating point -9999 N/A N/A N/A
latitude_lastbin Latitude of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 64-bit floating point -9999 N/A N/A N/A
latitude_lastbin_error Error in latitude of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 32-bit floating point -9999 N/A N/A N/A
local_beam_azimuth Azimuth of the unit pointing vector for the laser in the local ENU frame measured from North and positive towards East Radians 32-bit floating point N/A N/A -180 to 180 N/A
local_beam_elevation Elevation of the unit pointing vector for the laser in the local ENU frame measured from East-North plane and positive towards Up Radians 32-bit floating point N/A N/A 1.3962634 to 1.5707964 N/A
lon_highestreturn Longitude of highest detected return Degree 64-bit floating point N/A N/A -180 to 180 N/A
lon_lowestmode Longitude of center of lowest mode Degree 64-bit floating point N/A N/A -180 to 180 N/A
longitude_bin0 Longitude of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 64-bit floating point -9999 N/A N/A N/A
longitude_bin0_error Error in longitude of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 32-bit floating point -9999 N/A N/A N/A
longitude_lastbin Longitude of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 64-bit floating point -9999 N/A N/A N/A
longitude_lastbin_error Error in longitude of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate Degree 32-bit floating point -9999 N/A N/A N/A
shot_number Unique shot identifier Number 64-bit floating point N/A N/A N/A N/A
solar_azimuth The azimuth of the sun position vector from the laser bounce point position in the local ENU frame measured from North and is positive towards East Degree 32-bit floating point N/A N/A -180 to 180 N/A
solar_elevation The elevation of the sun position vector from the laser bounce point position in the local ENU frame measured from the East-North plane and is positive Up Degree 32-bit floating point N/A N/A -90 to 90 N/A
landsat_treecover Tree cover in the year 2010, defined as canopy closure for all vegetation taller than 5 m in height encoded as a percentage per output grid cell Percent 64-bit floating point -9999 N/A N/A N/A
modis_nonvegetated Percent non-vegetated from MODIS MOD44B V6 data Percent 64-bit floating point -9999 N/A N/A N/A
modis_nonvegetated_sd Percent non-vegetated standard deviation from MODIS MOD44B V6 data Percent 64-bit floating point -9999 N/A N/A N/A
modis_treecover Percent tree cover from MODIS MOD44B V6 data Percent 64-bit floating point -9999 N/A N/A N/A
modis_treecover_sd Percent tree cover standard deviation from MODIS MOD44B V6 data Percent 64-bit floating point -9999 N/A N/A N/A
algorithmrun_flag_aN For each L2A algorithm, the L2B algorithm is run if this flag is set to 1 which indicates sufficient waveform fidelity Class Flag 8-bit unsigned integer N/A N/A 0, 1 N/A
pgap_theta_aN Estimated Pgap (theta) from ground finding algorithm for each L2A processing version N/A 32-bit floating point -9999 N/A 0, 1 N/A
pgap_theta_error_aN Uncertainty of Pgap (theta) caused by ground finding algorithm for each L2A processing version N/A 32-bit floating point -9999 N/A N/A N/A
rg_aN Integral of the ground component in the received waveform for each L2A processing version Number 32-bit floating point -9999 N/A N/A N/A
rg_eg_amplitude_aN Amplitude of the extended Gaussian fit to the ground of RX waveform Number 32-bit floating point -9999 N/A N/A N/A
rg_eg_amplitude_error_aN Error in amplitude of the extended Gaussian fit to the ground of RX waveform Number 32-bit floating point -9999 N/A N/A N/A
rg_eg_center_aN Center of the extended Gaussian fit to the ground of RX waveform Nanoseconds 32-bit floating point -9999 N/A N/A N/A
rg_eg_center_error_aN Error in center of the extended Gaussian fit to the ground of RX waveform Nanoseconds 32-bit floating point -9999 N/A N/A N/A
rg_eg_chisq_aN Chi square of R (ground) fit N/A 32-bit floating point -9999 N/A N/A N/A
rg_eg_flag_aN Extended Gaussian fit status flag Class Flag 8-bit signed integer N/A N/A 0 to 255 N/A
rg_eg_gamma_aN Gamma value of the extended Gaussian fit to the ground of RX waveform N/A 32-bit floating point -9999 N/A N/A N/A
rg_eg_gamma_error_aN Error in gamma value of the extended Gaussian fit to the ground of RX waveform N/A 32-bit floating point -9999 N/A N/A N/A
rg_eg_niter_aN Number of iterations to converge extended Gaussian fit to RX waveform N/A 8-bit unsigned integer N/A N/A N/A N/A
rg_eg_sigma_aN Sigma value of the extended Gaussian fit to the ground of RX waveform Nanoseconds 32-bit floating point -9999 N/A N/A N/A
rg_eg_sigma_error_aN Error in sigma value of the extended Gaussian fit to the ground of RX waveform Nanoseconds 32-bit floating point -9999 N/A N/A N/A
rg_error_aN Error of the integral of the ground component in the received waveform for each L2A processing version Number 32-bit floating point -9999 N/A N/A N/A
rv_aN Integral of the vegetation component in the received waveform for each L2A processing version Number 32-bit floating point -9999 N/A N/A N/A
rx_energy_aN Received waveform energy Number 32-bit floating point -9999 N/A N/A N/A
shot_number Unique shot identifier Number 64-bit floating point N/A N/A N/A N/A

All beams included in the data product will contain the same sets of SDS layers.

Gaussian Fit Status Flag

Value Description
1 Convergence in chi² value
2 Convergence in parameter value
3 Convergence in chi² and parameter values
4 Convergence in orthogonality
5 Maximum number of iterations reached
6 Ftol too small (no further improvement)
7 Xtol too small (no further improvement)
8 Gtol too small (no further improvement)

Product Quality

Quality information is provided in section 6 of the User Guide.

Known Issues

  • Known Issues: Section 7 of the User Guide provides additional information on known issues.

  • Data acquisition gaps: GEDI data acquisitions were suspended on December 19, 2019 (2019 Day 353) and resumed on January 6, 2020 (2020 Day 6).

Documentation

Using the Data

Access Data

Citation

DOI: 10.5067/GEDI/GEDI02_B.001

About the Image

Plant Area Volume Density (PAVD) and elevation from the GEDI02_B Product.

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