The drought risk atlas: Enhancing decision support for drought risk management in the United States

•A drought risk atlas was created housing over 3000 stations with a 70 year average period of record.•Over 1 billion drought indices records have been generated up through 2012 and are freely available.•When fully completed, will house a cache of more than 500,000 gridded drought indices maps.•A robust web interface allows for multiple data and display queries at: droughtatlas.unl.edu.•The concept of using the DRA as a decision-support tool for drought planning is discussed.

SummaryDecision makers have continuously asked for better tools and resources to help them assess their risks related to climate variability and extremes. Drought is one of the risks they face, and the need for better drought risk tools and resources has also been expressed. With drought continuing to be one of the most problematic and costly natural disasters within the United States, and building on the work of the original National Drought Atlas (NDA) (1996), an updated and expanded Drought Risk Atlas (DRA) decision support tool for the United States was developed and is housed at the National Drought Mitigation Center. The DRA (1) provides weekly calculations of multiple indices/indicators, with more than a billion records made freely available, including the SPI, SPEI, PDSI, scPDSI, Deciles and U.S. Drought Monitor; (2) houses more than 3000 stations with data through 2012, nearly tripling the station count of the original NDA; (3) utilizes a much longer period of record, nearly double that of the NDA in most cases; (4) when fully completed, will house a cache of more than 500,000 gridded drought index maps; (5) will allow us to analyze and assess trends and various characteristics of drought, including frequency, intensity, duration and magnitude; (6) will become a resource for the National Weather Service (NWS) personnel around the country by transferring the application into the field through integration within the NWS's newly developed Local Climate Analysis Tool (LCAT); and (7) work directly with the National Integrated Drought Information System (NIDIS) program office to include the information contained in the DRA into NIDIS's regional drought early warning system pilot basins and the U.S. Drought Portal for broad dissemination to the user community and general public.