Assessing ICESat-2’s ability to estimate vertical foliage profile in comparison with ALS derived waveform LiDAR for forest management

Abstract

One-third of Earth’s land is covered by forest ecosystems, it immensely contributes to the global carbon budget. The functions and internal physiological processes of 3D structure of canopy also plays a key role in carbon dynamic. To increase the understanding of these processes and their contribution, the accurate measurements are needs to be produced. With The Spaceborne platform like ICESat-2 (The Ice, Cloud, and land Elevation Satellite-2) it is now possible to take the measurements of the three-dimensional structure and on the large landscape scales. Here, we evaluate the ability pf ICEsat-2 in deriving vertical foliage profile, in comparison with vertical foliage profile derived from simulated waveforms using ALS. This study uses (GORT) model to calculate PAVD, using gap fraction. The waveforms from ALS are simulated using Gedisimulator.The study further compares the PAVD from both using error matrix. The results do not show a great agreement between the PAVD values, but it gives the insights into the further parameters that needs to be studies and quantified for the increasing the accuracy in PAVD measurements from spaceborne Lidar. The one parameter, canopy and ground reflectance ratio that affects estimates of PAVD have been used in variation to understand the sensitivity of PAVD to the canopy and ground reflectance ratio.

Canopy and ground reflectance ratio does affect the PAVD estimates but it cannot alone explain the error in the estimates. This research concludes with suggestions for further research of the PAVD estimation on different landscapes, terrain and vegetation could provide a valuable information and the variability of essential parameters of the PAVD estimation model, and this might increase the accuracy of PAVD estimation from ATL08 product of ICEsat-2.