Performance evaluation and effect factor analysis of GEDI L2A data for building height retrieval

This study provides a valuable reference for the efficient generation of high-quality GEDI footprint data for building height retrieval. Based on the proposed GEDI data filtering method, we downloaded and processed the GEDI L2A V2 data for China in the year 2020 to generate high-quality GEDI data for building height retrieval. The 30-m Forest and Buildings removed Copernicus DEM (FABDEM) (Hawker et al., 2022) was utilized to eliminate footprints that failed to detect ground elevation, while the 10-m World Settlement Footprint 2019 map (Marconcini et al., 2021) was employed to exclude GEDI footprints in non-building areas. Ultimately, 973,608 high-quality GEDI footprints were obtained for China's built-up areas, effectively illustrating building heights. GEDI footprints are significantly sparser in southern China than in the north. Among these footprints, the maximum RH98 value is 148.01 m, the minimum value is 1.08 m, and the mean value is 13.26 m. Two distinct peaks are evident at RH98 values of approximately 7 m and 20 m, respectively. Additionally, it can be observed that building heights are notably higher in central and southern China compared to the northern and northwestern regions. These high-quality GEDI data provide accurate building height information and may contribute to wall-to-wall building height mapping research.