Monitoring of soil moisture using a microwave based variational wetness index

Satellite data have been largely used to detect and monitor flooding events. In particular, data acquired by passive radiometers were recognized as the most adequate to this aim, thanks to their suitable trade-off between temporal and spatial resolution. In this work, nine years of data acquired by the Advanced Microwave Scanning Radiometer (AMSR-E) aboard Earth Observing System (EOS) Aqua, have been investigated by means of the Robust Satellite Techniques (RST) approach, implementing a robust indicator of soil moisture variation, the Polarization Ratio Variation Index (PRVI). Such an index has been applied to analyze the flood which hit Pakistan during summer 2010. Preliminary results shown in this study demonstrated the potential of such an index in providing reliable information about the presence of extremely wet soils, especially when low frequency AMSR-E channels are used.