May 18, 2015

Future population exposure to US heat extremes

Bryan Jones, Brian C. O’Neill, Larry McDaniel, Seth McGinnis, Linda O. Mearns, Claudia Tebaldi
Nature Climate Change
  • Provides a new projection of population exposure to extreme heat for the continental United States that takes into account both climate change and human population change
  • Uses projections from a suite of regional climate models driven by global climate models and forced with the SRES A2 scenario and a spatially explicit population projection consistent with the socioeconomic assumptions of that scenario
  • Projects changes in exposure into the latter half of the twenty-first century
  • Finds that US population exposure to extreme heat increases four- to sixfold over observed levels in the late twentieth century, and that changes in population are as important as changes in climate in driving this outcome
  • Finds aggregate population growth, as well as redistribution of the population across larger US regions, strongly affects outcomes whereas smaller-scale spatial patterns of population change have smaller effects
  • States the relative importance of population and climate as drivers of exposure varies across regions of the country