A roadmap for high-resolution satellite soil moisture applications – confronting product characteristics with user requirements
Jian Peng, Clément Albergel, Anna Balenzano, Luca Brocca, Oliver Cartus, Michael H. Cosh, Wade T. Crow, Katarzyna Dąbrowska‐Zielińska, Simon Dadson, Malcolm Davidson, Patricia de Rosnay, Wouter Dorigo, Alexander Gruber, Stefan Hagemann, Martin Hirschi, Yann H. Kerr, Francesco Lovergine, Miguel D. Mahecha, Philip Marzahn, Francesco Mattia, Jan Musiał, Swantje Preuschmann, Rolf H. Reichle, Giuseppe Satalino, M. Silgram, Peter M. van Bodegom, Niko E. C. Verhoest, Wolfgang Wagner, Jeffrey P. Walker, U. Wegmüller, Alexander Loew
Abstract
Soil moisture observations are of broad scientific interest and practical value for a wide range of applications. The scientific community has made significant progress in estimating soil moisture from satellite-based Earth observation data, particularly in operationalizing coarse-resolution (25-50 km) soil moisture products. This review summarizes existing applications of satellite-derived soil moisture products and identifies gaps between the characteristics of currently available soil moisture products and the application requirements from various disciplines. We discuss the efforts devoted to the generation of high-resolution soil moisture products from satellite Synthetic Aperture Radar (SAR) data such as Sentinel-1 C-band backscatter observations and/or through downscaling of existing coarse-resolution microwave soil moisture products. Open issues and future opportunities of satellite-derived soil moisture are discussed, providing guidance for further development of operational soil moisture products and bridging the gap between the soil moisture user and supplier communities.