National Aeronautics and Space Administration

National Climate Assessment

NASA National Climate Assessment (NCA) Activities

NASA Indicators Solicitation Proposals

Development and Testing of Potential Indicators for the National Climate Assessment

Lead PI and Center: Rong Fu, The University of Texas at Austin
Title: Improving Assessment of Regional Climate Change in Supporting of Regional Resilience to Extreme Climate Events Over the US Southern Great Plains

"Flash" droughts refer to those droughts that intensify rapidly in spring and summer, coupled with strong increase of summer extreme temperatures, such as those that occurred over Texas in 2011 and the Great Plains in 2012.  Climate models failed to predict these flash droughts in 2011 and 2012 and are ambiguous in projecting their future changes, largely because of models' weakness in predicting summer rainfall and soil moisture feedbacks.  By contrast, climate models are more reliable in simulating changes of large-scale circulation and warming of temperatures during winter and spring seasons.  Thus, we propose to develop and test a physical climate indicator of the risk of "flash" droughts in summer by using the large-scale circulation and land surface conditions in winter and spring based on observed relationships between these conditions and their underlying physical mechanisms established by previous observations and numerical model simulations.

The proposed "flash" drought indicator (IFDW) will be developed and tested using NASA Modern Era Retropsective-Analysis for Research (MERRA), North American Land Data Assimilation (NLDAS) products, the Coupled Model Inter-comparison Project Phases 5 (CMIP5) models and a suite of satellite datasets.  IFDW will be mapped in a way similar to drought severity index shown at National Integrated Drought Information Center (NIDIS) with additional information about uncertainty, past and future probability distributions of IFDW.

The proposed IFDW has several advantages over the available drought indices that simply track local drought condition in past, present and future:

  1. It mitigates the weakness of current climate models in predicting future summer droughts and takes advantage of the models strength and our understanding of the mechanisms that control "flash" droughts;
  2. It provides actionable drought risk information for stakeholders before droughts become fully developed in current climate,
  3. It links future increase of temperatures in winter and spring to risk of "flash" droughts in summer.  Such a link would make the projected changes of the "flash" droughts more intuitive and compelling to high-level decision makers and public.                           
This investigation team consists of an experienced climate-drought researcher, a young postdoctoral researcher specialized in applying climate science to support decision making and a leader of state water resource planner with strong track recording of working together previously.  The development and communication of the IFDW will be guided by strong expertise in communicating drought information to stakeholders from the beginning to the end of this proposed project.