SCATSAT-1 backscattering coefficient over distinct land surfaces and its dependence on soil moisture and vegetation dynamics

摘要

The objective of this study is to examine the potential of SCATSAT-1 data for estimating the soil moisture and vegetation over the continental regions by evaluating the variabilities in backscattering coefficients measured over different land surface types. The SCATSAT-1 is Ku-band wind Scatterometer, which provides backscattering coefficient measurements over the globe in HH and VV polarization at fixed incidence angles. Variabilities in the backscatter coefficients over different land surfaces, mainly over four different geo-climatological regions of India, are studied based on 3 years of SCATSAT-1 dataset in conjunction with other collocated measurements. The SCATSAT-1 backscattering coefficient provides the quantitative measure of the seasonality over a region due to unique distribution of soil moisture and vegetation characteristics of that region. The variabilities in soil moisture and vegetation in these regions are compared and applicability of change detection method for estimating the soil moisture over these regions has been analysed. Based on regression analysis on SMOS measured soil moisture and SCATSAT-1 measured backscattering coefficient, a relationship has been established for the soil moisture estimation from the SCATSAT-1 backscattering coefficient.