Page 1 of 1

Gedi Tree height question

Posted: Thu Nov 09, 2023 5:07 pm America/New_York
by LP DAAC - lien
I want to consult a GEDI worker about some GEDI data processing problems, and hope to get the help of the GEDI staff. I would like to know whether the tree height obtained through waveform decomposition is the average height within 25 meters of the light spot size or the highest value of the GEDI L1B data. At the same time, I would like to ask how the canopy height in GEDI L2A is obtained from the waveform data in L1B, and is it the L2A canopy height data obtained through Gaussian decomposition? I hope to get your reply. I wish you all the best, peace and happiness.

Re: Gedi Tree height question

Posted: Thu Nov 09, 2023 5:08 pm America/New_York
by LP DAAC - lien
It is the highest value of the L1B data, and how that is done is described in the Level-2A ATBD.

Section 4.3.4 details how the canopy top (highest detected return) is found. Section 4.3.6 details how the ground (lowest detected mode) is found. Section 5 details how these waveform ranging points (in the sensor coordinate system) are mapped to elevation, latitude and longitude. The difference between the highest detected return elevation and lowest detected mode elevation is RH100. Other RH metrics depend on the distribution of returned energy between the highest detected return and the lowest detected return (lowest detected return is also described in Section 4.3.4). The values of the highest detected return elevation and lowest detected mode can differ between algorithm setting parameter groups, as described in the Level 2A User Guide and Section 4.3.3 in the ATBD.