The drought index (DI) is computed using SMOS derived root zone soil moisture (RZSM) monthly fields. The concept is to consider 13 years of SMOS data (2010-2022). The RZSM monthly mean and max over the period is iused to compute a soil water deficit to remove seasonal variability. from teh soil water deficit a soil moisture drought index is computed .The range of values for SMDI lies between -4 to +4, with -4 representing extreme dry conditions and +4 representing extreme wet conditions.

The SMOS Level-4 SMAP Compatible Brightness Temperatures (BT) product provides an unbiased version of the SMOS Level-3 BT with respect to the SMAP Enhanced Level-3 BT. This data set is self-sufficient but it can also be used along with the SMAP Level-3 Enhanced BT for applications for which spatial coverage and revisit frequency of the BT measurements are essentials.