Validation of ICESat-2 terrain and canopy heights in boreal forests

• DOI: 10.1016/j.rse.2020.112110
• Publication Date: 2020-09-28T19:10:41Z
• Authors: Amy Neuenschwander; Eric Guenther; Joanne C. White; Laura Duncanson; Paul Montesano
• Keywords: Elevation (ballistics); Tree canopy

NASA's Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) launched in the fall of 2018 is collecting vegetation canopy height terrain measurements globally. In this paper we validate heights estimated from 11 months ICESat-2 data using airborne lidar collected southern Finland. Overall, ATL08 product agreed with vertical errors less than 75 cm (mean = −0.07 m; MAE 0.53 m, RMSE 0.73 n observations 909,467). had positive bias (33 cm) when permanent snow cover was present compared to lidar. Canopy derived varied significantly by beam selection (i.e. strong versus weak). Use weak beams increased underestimation 1.06 m RMSE% 8.08%. The lowest were associated beam/night/summer acquisitions, which underestimated 0.56 (Bias% 3.18; 13.75%), followed beam/day/summer acquisitions 2.85%; 14.77%). For study area managed, coniferous-dominated boreal forests, found that for ranging 40 85% within range, on average, missed top 11–13% heights. At low (<40%), photons are more likely be reflected surface rather due lower amount present. Although not designed retrievals, herein have demonstrated can provide a useful source information forests. By quantifying accuracy characterized ATL08, insights capabilities limitations these applications. Our results indicate end users interested retrievals particular should avoid use forest conditions.