Skulovich Olya, Li Xiaojun, Wigneron Jean-Pierre, Gentine Pierre
Columbia University, New York, NY, 10027, USA.
NRAE, UMR1391 ISPA, University of Bordeaux, F-33140, Villenave d'Ornon, France.
Sci Data. 2024 Aug 28;11(1):936. doi: 10.1038/s41597-024-03810-2.
The L-band vegetation optical depth data garners significant interest for its ability to effectively monitor vegetation, thanks to minimal saturation within this frequency range. However, the existing datasets have limited temporal coverage, constrained by the start of the respective satellite missions. Global L-band equivalent AI-Based Vegetation Optical Depth or GLAB-VOD is a global long-term consistent microwave vegetation optical depth dataset created using machine learning to expand the SMAP-IB VOD dataset temporal coverage from 2015-2020 to 2002-2020. The GLAB-VOD dataset has an 18-day temporal resolution and 25 km spatial resolution on the EASE2 grid and covers 2002-2020. An auxiliary consistent daily brightness temperature product, called GLAB-TB, is developed in parallel and ensures the consistency of the VOD product across time periods with different microwave satellites. As a result of its temporal consistency, this dataset can be used to study long-term global and regional trends in vegetation biomass and utilized in any other applications where long-term consistency is necessary. The GLAB-VOD dataset shows excellent spatial correlation globally when compared with biomass (up to R = 0.92) and canopy height (R = 0.93), outperforming its target dataset, SMAP-IB VOD.
L波段植被光学深度数据因其在该频率范围内饱和度极低,能够有效监测植被而备受关注。然而,现有的数据集受各自卫星任务开始时间的限制,时间覆盖范围有限。全球基于人工智能的L波段等效植被光学深度数据集(GLAB-VOD)是一个全球长期一致的微波植被光学深度数据集,它利用机器学习将SMAP-IB VOD数据集的时间覆盖范围从2015年至2020年扩展到2002年至2020年。GLAB-VOD数据集在EASE2网格上具有18天的时间分辨率和25公里的空间分辨率,覆盖2002年至2020年。同时还开发了一个辅助的每日一致亮度温度产品,称为GLAB-TB,以确保VOD产品在不同微波卫星的时间段内的一致性。由于其时间一致性,该数据集可用于研究植被生物量的长期全球和区域趋势,并可用于任何需要长期一致性的其他应用。与生物量(高达R = 0.92)和冠层高度(R = 0.93)相比,GLAB-VOD数据集在全球范围内显示出极好的空间相关性,优于其目标数据集SMAP-IB VOD。