Toward Mapping Gridded Drought Indices to Evaluate Local Drought in a Rapidly Changing Global Environment

Uncertain future climate, recent persistent droughts, and subsequent water conflicts increasingly threaten the sustainability of regional water resources in the United States. Climate change and ongoing water disputes brought about by changes in water availability and timing emphasize the need for decision makers to develop proactive adaptive management strategies to mitigate losses. Developing a drought management system equipped with advanced visualization settings is critical to lay out drought evolvement at local scales, yet an effort has not been made to evaluate how different spatial discretization can represent local drought as opposed to conventional drought monitoring. Gridded drought indices, including the standardized precipitation index (SPI), Palmer drought severity index (PDSI), and Hydrologic drought index (HDI) at high-resolution spatial (12 km by 12 km) scales are demonstrated to provide useful insights to evaluate local drought possibly driven by a rapidly changing global environment. A new method for duration factors in PDSI is also discussed to better represent drought conditions over time and space. Copyright Springer Science+Business Media Dordrecht 2014