LVIS Data Structure (LDS) 2.0.2 Description


Byte Order: Binary files are Big Endian unless otherwise noted.


Reference Frame: International Terrestrial Reference Frame (ITRF 2008 / WGS-84 Ellipsoid).


General Notes:

  • A release is comprised of two or more file types sharing a common origin. All files within the release have equal record numbers, and correspond to one another laser shot for shot. (i.e. record 1000 in the .h5 file will be the same laser shot as record 1000 in the .txt file for a given data set)
  • The Level2 data product used for the Greenland 2017 campaign differs slightly from that used for the ABoVE 2017 campaign, containing 3 additional data products (referred to as hlon, hlat and zh).

Datasets: 2017



Level 1B Geolocated LVIS Waveforms (HDF format)

Item Byte Size Format Units Item Description
LFID 4 unsigned longword integer LVIS file identification
shotnumber 4 unsigned longword integer Laser shot number assigned during collection
azimuth 4 single precision floating point degrees Azimuth angle of laser beam
incidentangle 4 single precision floating point degrees Off-nadir incident angle of laser beam
range 4 single precision floating point meters Distance between the instrument and the ground
time 8 double precision floating point seconds UTC decimal seconds of the day
lon0 8 double precision floating point degrees Longitude of the highest sample of the waveform (Degrees East)
lat0 8 double precision floating point degrees Latitude of the highest sample of the waveform (Degrees North)
z0 4 single precision floating point meters Elevation of the highest sample of the waveform
lon1215 8 double precision floating point degrees Longitude of the lowest detected signal (Degrees East)
lat1215 8 double precision floating point degrees Latitude of the lowest detected signal (Degrees North)
z1215 4 single precision floating point meters Elevation of the lowest sample of the waveform
sigmean 4 single precision floating point counts Signal mean noise level, calculated in-flight
txwave counts Transmitted waveform, 256 bins long, 12bits @ 1GHz
rxwave counts Return waveform, 1216 bins, 12bits @ 1GHz

Level 2 Geolocated Surface Elevation and Height Product (ASCII Text format)


Item Item Description
LFID LVIS File Identification
shotnumber Laser shot number assigned during collection
time UTC decimal seconds of the day
glon Longitude of the lowest detected mode within the waveform (Degrees East)
glat Latitude of the lowest detected mode within the waveform (Degrees North)
zg Mean elevation of the lowest detected mode within the waveform
tlon Longitude of the highest detected signal (Degrees East)
tlat Latitude of the highest detected signal (Degrees North)
zt Elevation of the highest detected signal
hlon* Longitude of the center of the highest mode within the waveform (Degrees East)
hlat* Latitude of the center of the highest mode within the waveform (Degrees North)
zh* Mean elevation of the highest mode within the waveform (m)
RH10 Height in meters (relative to zg) at which 10% of the waveform energy occurs
RH15 Height in meters (relative to zg) at which 15% of the waveform energy occurs
RH20 Height in meters (relative to zg) at which 20% of the waveform energy occurs
RH25 Height in meters (relative to zg) at which 25% of the waveform energy occurs
RH30 Height in meters (relative to zg) at which 30% of the waveform energy occurs
RH35 Height in meters (relative to zg) at which 35% of the waveform energy occurs
RH40 Height in meters (relative to zg) at which 40% of the waveform energy occurs
RH45 Height in meters (relative to zg) at which 45% of the waveform energy occurs
RH50 Height in meters (relative to zg) at which 50% of the waveform energy occurs
RH55 Height in meters (relative to zg) at which 55% of the waveform energy occurs
RH60 Height in meters (relative to zg) at which 60% of the waveform energy occurs
RH65 Height in meters (relative to zg) at which 65% of the waveform energy occurs
RH70 Height in meters (relative to zg) at which 70% of the waveform energy occurs
RH75 Height in meters (relative to zg) at which 75% of the waveform energy occurs
RH80 Height in meters (relative to zg) at which 80% of the waveform energy occurs
RH85 Height in meters (relative to zg) at which 85% of the waveform energy occurs
RH90 Height in meters (relative to zg) at which 90% of the waveform energy occurs
RH95 Height in meters (relative to zg) at which 95% of the waveform energy occurs
RH96 Height in meters (relative to zg) at which 96% of the waveform energy occurs
RH97 Height in meters (relative to zg) at which 97% of the waveform energy occurs
RH98 Height in meters (relative to zg) at which 98% of the waveform energy occurs
RH99 Height in meters (relative to zg) at which 99% of the waveform energy occurs
RH100 Height in meters (relative to zg) at which 100% of the waveform energy occurs
azimuth Azimuth angle of the laser beam
incidentangle Off-nadir incident angle of the laser beam
range Distance between the instrument and the ground
Complexity Complexity metric for the return waveform
channel_zt Flag indicating LVIS channel waveform contained in the Level-1B file
channel_zg Flag indicating LVIS channel used to locate ZG
channel_rh Flag indicating LVIS channel used to calculate RH metrics

*This item is contained in LDS2.0.2b (used for Greenland 2017) but not in 2.0.2a (used for ABoVE 2017).


Use the following python script to view Level 1B and Level 2 data products in the LDS v2.0 format. You will need to install the h5py and numpy python packages in order for this script to work.

py_waveplot.py