Framework for comparing plant height measurements from spaceborne LiDAR systems

Abstract:

Plant height is a critical determinant of ecosystem function and net primary production, biomass and terrestrial carbon stocks. Accurate estimation of height provides critical inputs to carbon and dynamic vegetation models, and will provide information that is critical for sustainable ecosystem management. Current state-of-the art remote sensing has made tremendous contributions to the detection and monitoring of plant height. Specifically, the development of free and open LiDAR technologies such as ICESat-2 and GEDI can provide comprehensive global datasets of plant height at informative resolutions. However, the practical use of these observations globally is compromised by the large uncertainties of different height measurements. To seek harmonization and global consensus of plant height estimation, we are creating a framework to enable practical comparison and evaluation of different height measurements through examining the determinants of uncertainties of ICESat-2 and GEDI. The proposed framework will compare the height estimation from GEDI and ICESat-2 with plant height observations in sites with varied conditions including biome, season, woody cover, soil condition, species, and topography, which have potential impacts on height observations. Quantification of uncertainties in measuring plant height from different sapceborne LiDAR systems allows for their optimized combination and multi-temporal comparison.