| dc.description.abstract | In the south central United States, drought is a prevalent natural disaster, and its impacts extend much farther than its drain on the region’s natural resources. Unfortunately, local impacts of drought may differ spatially such that similar atmospheric conditions lead to different hydrologic impacts from community to community. In addition, spatial variations in drought intensity may be smaller than the size of a climate division, resulting in climate division-scale drought indices being inadequate. This study provides a spatial analysis of the impacts of drought within the Chickasaw Nation in south central Oklahoma. The goal of this study is to determine if drought was better represented by the Standardized Precipitation Index (SPI) or the Standardized Precipitation Evapotranspiration Index (SPEI) on 1-, 3-, and 12-month time scales with any spatial or seasonal differences, to see if climate-division scale data is representative of the localized impacts, and to understand how drought impacts the hydrologic resources across this study region. This study uses SPI and SPEI calculated using Oklahoma Mesonet stations within the tribal nation, and compared them to the U.S. Drought Monitor to assess the quality of the data. This was repeated for Climate division-scale SPI and SPEI to observe any differences in drought representation. Next, interpolated values of SPI and SPEI were used to distinguish any temporal, spatial, and seasonal patterns. Finally, through a case study of the 2011 – 2015 drought, this study investigated the hydrologic impacts of drought by comparing SPI and percentage of normal streamflow across the region, and calculating temporal cross correlations to distinguish any relationships between the two time series. | en_US |
