A Comparison of the National Drought Monitoring Index with New Drought Indices Based on Remotely Sensed SMAP Data and In Situ COSMOS Observations

Timely monitoring of drought conditions is critical for agriculture, insurance, and government applications. The National Drought Mitigation Center publishes a widely used weekly drought monitoring index which is authored by experts examining multiple remotely sensed data sources, in situ sensors, and local reports. However, more timely data at a higher spatial resolution would further help to mitigate the socio-economic effects of droughts.

In response, we are developing a new drought index based on remotely-sensed SMAP data. This index will be updated every 3 days, globally, at a resolution of approximately 9km. In order to validate our approach, we also plan to derive a drought index using in situ COSMOS sensors. COSMOS soil moisture sensors provide meso-scale soil moisture measurements (approximately 0.6 km resolution) with high temporal resolution, and their area-averaged measurements are attractive for validating satellite measurements. We will directly compare our drought indices with NDMC’s index for selected drought events. We will also discuss future work incorporating additional data sources to further improve our drought indices. Our drought index data will be viewable via a public website, and we will briefly discuss the cloud infrastructure required for the on-demand processing and visualization of our results.