Water Resources Research Act Program

Details for Project ID 2014ID199B

Development of Soil Moisture Droght Index (SODI) to Characterize Hydrological Droughts in the Northwest

Institute: Idaho
Year Established: 2014 Start Date: 2014-03-01 End Date: 2015-02-28
Total Federal Funds: $15,000 Total Non-Federal Funds: $30,000

Principal Investigators: Jae Ryu

Abstract: A new drought index named Soil Moisture Drought Index (SODI) will be developed to characterize hydrological droughts in the northwest. The premise of the index is based on how much water is required to attain soil moisture at field capacity. The SODI captures variations of precipitation, temperature, and soil moisture variation over time. Three widely used drought indices, including SPI, SPEI and the self-calibrated PDSI (sc-PDSI) will be compared with SODI for cross-validation based on local hydrological variables, such as streamflow, reservoir storage, and groundwater level. Results will show how well SODI outperforms the existing drought indices in the sense that SODI can better detect and quantify the extended severe droughts in the Northwest possibly driven by uncertain future climate.