NWC REU 2017
May 22 - July 28



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Future Projections of Heat Waves and Cooling Degree Days in Large Cities Across the South-Central United States

Melanie Schroers, Derek Rosendahl, Adrienne Wootten, and Renee McPherson


What is already known:

  • Heat is one of the leading causes of weather related mortality in the United States.
  • Studies have shown that heat waves will increase in frequency, duration, and intensity under anthropogenic climate change.
  • Heat waves lead to increased cooling requirements, mortality, and power outages.

What this study adds:

  • In large cities in south-central United States the number of heat waves per year will more than triple by the late century, 2075-2099.
  • The need for cooling, measured by cooling degree days, in these large cities is shown to increase up to 85%.
  • Cities should start planning for future impacts from increased heat related events.


Urban environments are particularly vulnerable to extreme heat events, otherwise known as heatwaves. To help better prepare cities, regional future climate projections of heat waves are necessary. Previous studies have shown that heat waves will become more frequent, longer in duration and stronger in intensity. In this analysis, we focus on projections of heat waves and cooling degree days in six large cities across the south-central United States. An ensemble of statistically downscaled global climate model simulations were used to look at heat waves and cooling degree days for a historical period from 1981-2005 and a late century future time period from 2075-2099. Heat waves were found to more than triple for each city and cooling degree days were found to increase anywhere from 50 to 85% by late century. In conclusion, already vulnerable environments will experience even more heat stress with an increased need for cooling. This could lead to a higher and increased mortality.

Full Paper [PDF]