Science Source

Future population exposure to US heat extremes

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