Potential Changes to Extreme Temperature and Precipitation across the U.S. Through 2100 from Three Downscaled Climate Scenarios

Extreme weather events can have a myriad of devastating societal impacts, including effects on human health, the environment, agriculture, land use, and the economy.  Consequently, there is tremendous interest in quantifying the potential changes to extreme temperature and precipitation as a result of a changing climate.  This presentation will show projected changes to extreme weather events under three climate change scenarios.  Simulations from the National Center for Atmospheric Research/Department of Energy (NCAR/DOE) Community Earth System Model (CESM) and the Geophysical Fluid Dynamics Laboratory Coupled Model (GFDL CM3) are dynamically downscaled to a 36-km resolution for the contiguous U.S. using the Weather Research and Forecasting (WRF) model.  Two of the Representative Concentration Pathways (RCPs) are chosen:  RCP 4.5, which is a scenario where radiative forcing stabilizes at 4.5 W m^-2 in the year 2100; and RCP 8.5, a more extreme warming pathway.  The climate change following both of the RCPs is assessed relative to recent historical climate simulated by CESM and downscaled by WRF, as is the climate change for GFDL CM3 under RCP 8.5.  The analysis will focus on differences in projected extremes of temperature and precipitation using hourly output across the U.S. over the 76-year period 2025-2100.