GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain
Information about forest structures is becoming crucial to earth's global carbon cycle, forest habitats, and biodiversity. The Global Ecosystem Dynamics Investigation (GEDI) provides 25-m diameter footprints of the surface for 3-D structure measurements. The main goal of this study is to...
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IEEE
2021-01-01
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| Series: | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
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| Online Access: | https://ieeexplore.ieee.org/document/9432712/ |
| _version_ | 1818588416824049664 |
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| author | Elia Quiros Maria-Eugenia Polo Laura Fragoso-Campon |
| author_facet | Elia Quiros Maria-Eugenia Polo Laura Fragoso-Campon |
| author_sort | Elia Quiros |
| collection | DOAJ |
| description | Information about forest structures is becoming crucial to earth's global carbon cycle, forest habitats, and biodiversity. The Global Ecosystem Dynamics Investigation (GEDI) provides 25-m diameter footprints of the surface for 3-D structure measurements. The main goal of this study is to compare 12 031 footprints of GEDI data with other airborne and spaceborne digital elevation models (DEMs) for Southwest Spain. Ground elevation differences [elevation of the lowest mode (ELM)] are analyzed by comparing GEDI measurements with airborne laser scanning (ALS) LiDAR- and TanDEM-X-derived DEMs. The vertical structure (RH100) is compared to the ALS LiDAR measurement. Ten zones are analyzed, considering different degrees of coverage and slopes. We achieved a root mean square error (RMSE) of 6.13 m for the ELM when comparing GEDI and LiDAR data and an RMSE of 7.14 m when comparing GEDI and TanDEM-X data. For some of the studied areas, these values were considerably smaller, with RMSE values even lower than 1 m. For the RH100 metric, an RMSE of 3.56 m was achieved when comparing GEDI and LiDAR data, but again with a minimum value of 2.09 m for one zone. The results show a clear relation to coverage and slope, especially for the latter. This work also evaluates the positional uncertainty of GEDI footprints, shifting them ±10 and ±5 m along and across the track of the satellite orbit and their intermediate angular positions. The outcomes reveal a strong tendency to obtain better results in the ELM when setting the footprint to 270° and displacing it within 10 m of its positional uncertainty in comparison with the LiDAR and TanDEM-X data. |
| first_indexed | 2024-12-16T09:24:25Z |
| format | Article |
| id | doaj.art-b3dac5b6486a44958b897584337ae00e |
| institution | Directory Open Access Journal |
| issn | 2151-1535 |
| language | English |
| last_indexed | 2024-12-16T09:24:25Z |
| publishDate | 2021-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing |
| spelling | doaj.art-b3dac5b6486a44958b897584337ae00e2022-12-21T22:36:41ZengIEEEIEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing2151-15352021-01-01145285529910.1109/JSTARS.2021.30807119432712GEDI Elevation Accuracy Assessment: A Case Study of Southwest SpainElia Quiros0https://orcid.org/0000-0002-8429-045XMaria-Eugenia Polo1https://orcid.org/0000-0002-7598-9998Laura Fragoso-Campon2https://orcid.org/0000-0003-0397-6247Department of Graphic Expression, University of Extremadura, Polytechnic School, Cáceres, SpainDepartment of Graphic Expression, University of Extremadura, University Centre of Mérida, Mérida, SpainDepartment of Graphic Expression, University of Extremadura, Polytechnic School, Cáceres, SpainInformation about forest structures is becoming crucial to earth's global carbon cycle, forest habitats, and biodiversity. The Global Ecosystem Dynamics Investigation (GEDI) provides 25-m diameter footprints of the surface for 3-D structure measurements. The main goal of this study is to compare 12 031 footprints of GEDI data with other airborne and spaceborne digital elevation models (DEMs) for Southwest Spain. Ground elevation differences [elevation of the lowest mode (ELM)] are analyzed by comparing GEDI measurements with airborne laser scanning (ALS) LiDAR- and TanDEM-X-derived DEMs. The vertical structure (RH100) is compared to the ALS LiDAR measurement. Ten zones are analyzed, considering different degrees of coverage and slopes. We achieved a root mean square error (RMSE) of 6.13 m for the ELM when comparing GEDI and LiDAR data and an RMSE of 7.14 m when comparing GEDI and TanDEM-X data. For some of the studied areas, these values were considerably smaller, with RMSE values even lower than 1 m. For the RH100 metric, an RMSE of 3.56 m was achieved when comparing GEDI and LiDAR data, but again with a minimum value of 2.09 m for one zone. The results show a clear relation to coverage and slope, especially for the latter. This work also evaluates the positional uncertainty of GEDI footprints, shifting them ±10 and ±5 m along and across the track of the satellite orbit and their intermediate angular positions. The outcomes reveal a strong tendency to obtain better results in the ELM when setting the footprint to 270° and displacing it within 10 m of its positional uncertainty in comparison with the LiDAR and TanDEM-X data.https://ieeexplore.ieee.org/document/9432712/Digital elevation models (DEMs)error analysisforestryuncertaintyvegetation mapping |
| spellingShingle | Elia Quiros Maria-Eugenia Polo Laura Fragoso-Campon GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing Digital elevation models (DEMs) error analysis forestry uncertainty vegetation mapping |
| title | GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain |
| title_full | GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain |
| title_fullStr | GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain |
| title_full_unstemmed | GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain |
| title_short | GEDI Elevation Accuracy Assessment: A Case Study of Southwest Spain |
| title_sort | gedi elevation accuracy assessment a case study of southwest spain |
| topic | Digital elevation models (DEMs) error analysis forestry uncertainty vegetation mapping |
| url | https://ieeexplore.ieee.org/document/9432712/ |
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