New ascat vegetation optical depth (IB-VOD) retrievals over Africa

Xiangzhuo Liu (1) , J.-P. Wigneron (1) , Frédéric Frappart (2) , Nicolas Baghdadi (3) , Mehrez Zribi (4) , Thomas Jagdhuber (5) , Xiaojun Li (1) , Mengjia Wang (1) , Lei Fan (6) , Christophe Moisy (1)

1 UMR ISPA - Interactions Sol Plante Atmosphère
2 ESS - Department of Earth System Science [Irvine]
3 UMR TETIS - Territoires, Environnement, Télédétection et Information Spatiale
4 CESBIO - Centre d'études spatiales de la biosphère
5 DLR Microwaves and Radar Institute
6 NUIST - Nanjing University of Information Science and Technology

Vegetation Optical Depth (VOD) plays an important role in monitoring the earth ecosystems. There are many VOD products released based on different satellites and frequencies. But most of the VOD products are derived from passive microwave data, and very few active VOD products have been released to date. This study investigated retrievals of the active microwave VOD product from C-band ASCAT (Advanced SCATterometer) observations using the water cloud model in large areas. To achieve this, the ASCAT backscatter data and ECMWF soil moisture data were used as inputs to retrieve ASCAT VOD over the whole Africa. The correlation between the retrieved VOD product and proxies of vegetation density (Saatchi biomass) were used to evaluate the model performance.

Mots clés: ASCAT; VOD; Water Cloud Model

Domaines: Interfaces continentales, environnement; Ingénierie de l'environnement

Xiangzhuo Liu, J.-P. Wigneron, Frédéric Frappart, Nicolas Baghdadi, Mehrez Zribi, et al.. New ascat vegetation optical depth (IB-VOD) retrievals over Africa. IGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium, Sep 2020, Waikoloa, Hawaii, United States. pp.5011-5013, ⟨10.1109/IGARSS39084.2020.9324232⟩. ⟨hal-03165644⟩