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Standardized Precipitation-Evapotranspiration Index for western United States, 2001-2014, derived from gridMET climate estimates

October 20, 2020

These data are 30m by 30 m grids of the mean Standardized Precipitation-Evapotranspiration Index (SPEI) between 2001-2014 in the western United States. The SPEI index was developed by Sergio M. Vicente-Serrano and coauthors (https://spei.csic.es/index.html). Source evapotranspiration and precipitation data were generated by gridMET (http://www.climatologylab.org/gridmet.html).