getLevel2BVPM: Get GEDI Canopy Cover and Vertical Profile Metrics (GEDI...

In carlos-alberto-silva/rGEDI: NASA's Global Ecosystem Dynamics Investigation (GEDI) Data Visualization and Processing

Get GEDI Canopy Cover and Vertical Profile Metrics (GEDI Level2B)

Description

This function extracts information from GEDI Level2B data: Total Plant Area Index, Foliage Height Diversity, Foliage Clumping Index, Total Gap Probability (theta), and Total canopy cover.

Usage

getLevel2BVPM(
  level2b,
  cols = c("beam", "shot_number", "algorithmrun_flag", "l2b_quality_flag", "delta_time",
    "sensitivity", "solar_elevation", "latitude_lastbin", "latitude_bin0",
    "longitude_bin0", "longitude_lastbin", "elev_highestreturn", "elev_lowestmode",
    "rh100", "pai", "fhd_normal", "omega", "pgap_theta", "cover")
)

Arguments

level2b	A GEDI Level2B object (output of readLevel2B() function). An S4 object of class "gedi.level2b".
cols	A character vector containing the list of columns to be extracted. See the default columns in the description.

Details

These are the biophysical variables and additional information extracted by default:

• beam Beam identifier

• shot_number Shot number

• algorithmrun_flag The L2B algorithm is run if this flag is set to 1 indicating data have sufficient waveform fidelity for L2B to run

• l2b_quality_flag L2B quality flag

• delta_time Transmit time of the shot since Jan 1 00:00 2018

• sensitivity Maxmimum canopy cover that can be penetrated

• solar_elevation Solar elevation

• latitude_lastbin Latitude of last bin of the pgap_theta_z, interpolated from L1B waveform coordinate

• latitude_bin0 Latitude of first bin of the pgap_theta_z, interpolated from L1B waveform coordinate

• elev_highestreturn Elevation of highest detected return relative to reference ellipsoid

• elev_lowestmode Elevation of center of lowest mode relative to reference ellipsoid

• rh100 RH100 slice

• pai Total Plant Area Index

• fhd_normal Foliage Height Diversity

• omega Foliage Clumping Index

• pgap_theta Total Gap Probability (theta)

• cover Total canopy cover

Every other columns in the GEDI2B product are also available, you can specify each column by using the cols parameter.

Value

Returns an S4 object of class data.table::data.table containing the Vegetation Profile Biophysical Variables.

See Also

https://lpdaac.usgs.gov/products/gedi02_bv002/

Examples

# Specifying the path to GEDI level2B data (zip file)
outdir = tempdir()
level2B_fp_zip <- system.file("extdata",
                  "GEDI02_B_2019108080338_O01964_T05337_02_001_01_sub.zip",
                  package="rGEDI")

# Unzipping GEDI level2A data
level2Bpath <- unzip(level2B_fp_zip,exdir = outdir)

# Reading GEDI level2B data (h5 file)
level2b<-readLevel2B(level2Bpath=level2Bpath)

# Extracting GEDI Vegetation Profile Biophysical Variables
level2BVPM<-getLevel2BVPM(level2b, cols=c("beam", "shot_number"))
head(level2BVPM)

close(level2b)

carlos-alberto-silva/rGEDI documentation built on Oct. 18, 2024, 4:46 a.m.