Purdue Climate Change Research Center

Impacts of High Resolution Extreme Events on U.S. Energy Demand and CO2 Emissions in the 21st Century

Funded by the Department of Energy

The overall objective of this project is to build fundamental knowledge regarding the impact of weather extremes on particularly sensitive portions of the energy sector. This year, work focused on

  1. Developing present relationships between weather extremes and the heating/cooling demand of the U.S.
  2. Analyzing the statistics of daily-scale temperature and precipitation events, and
  3. Examining the intensification of heat stress.

Using the Vulcan fossil fuel CO2 emissions inventory, the Gurney group constructed a framework to evaluate the relationship between the space heating CO2 emissions of the Vulcan inventory and surface temperature, at an hourly resolution. The work focused on heating in the residential and commercial sectors, with cooling to be completed in the future.

Diffenbaugh and his group examined the ability of a high-resolution nested climate model RegCM3, to capture the statistics of daily-scale temperature and precipitation events over the conterminous U.S., using observational and reanalysis data for comparison. Their findings appear in a recent paper in Climate Dynamics. Briefly, the authors find that the analysis does capture the pattern of mean, interannual variability, and trend in tails of the daily temperature and precipitation distributions. Consistent biases were found, however, including wet biases in the western U.S. and hot biases in the southern and central U.S. These biases indicate that relatively subtle errors in the simulation of atmospheric circulation and surface energy and moisture fluxes can produce relatively large errors in the simulations of the statistics.

Using a suite of global and nested climate model experiments, the group quantified the the potential emergence of extreme heat in the U.S. Included in that suite is the first high-resolution, multi-decadal, ensemble climate model experiment for the United States (“the RCM ensemble”), as well as output from the CMIP3 climate model archive (“the GCM ensemble”). The hottest season of the 1951-1999 period was used as a metric for extreme heat. They find that the exceedence of this historical hottest-season threshold increases over the first four decades of the 21st century and that the pattern and magnitude of emerging heat stress in the coming decades is not dictated simply by the mean warm-season temperature change. In addition, they find that relative to the GCM ensemble, the RCM ensemble offers a more realistic representation of the magnitude and spatial heterogeneity of the warm-season temperature. This work was presented at the International Scientific Congress on Climate Change in Copenhagen, Denmark in March, 2009.

Walker, M.D. and N.S. Diffenbaugh, Evaluation of high-resolution simulations of daily-scale temperature and precipitation over the United States. Climate Dynamics, (2009) 10.1007/s00382-009-0603-y.


  • Noah Diffenbaugh, EAS
  • Kevin Gurney, EAS and Agronomy

Contact Information

Purdue University
203 S. Martin Jischke Drive
MANN 105
West Lafayette, IN 47907