Heat Stress and Temperature Extremes

Climate warming is expected to lead to greater heat stress on humans and ecosystems during the warm season. GFDL scientists are working to provide improved scientific information on heat stress and temperature extremes in a changing climate.

Climate scientists are exploring the impact of global warming on heat stress and temperature extremes at the regional scale, including over the United States. Increases in both average and extreme temperatures due to greenhouse warming have already been detected over many regions of the globe. In addition, further increases in surface temperatures and moisture are an extremely robust of climate models over the 21st century under various emission scenarios.

GFDL Research

GFDL scientists have studied the impact of anthropogenic warming on the occurrence of heat waves, on extreme seasonal temperatures and on heat stress affecting human activity. For example, heat waves are projected to occur substantially more often (by a factor of four or more in some regions of the U.S.) by the end of the 21st century under typical future emission scenarios. Extreme springtime temperatures occurring during 2012 over the eastern U.S. have been linked to anthropogenic warming.

GFDL research has shown that moisture increases accompanying global warming are expected to have an important impact beyond temperature in elevating heat stress as felt by humans. This effect will be felt most acutely in summertime and in moist tropical and subtropical regions, but strong increases in heat stress are also projected for most midlatitude regions as well. Increases in heat stress associated with anthropogenic warming are projected to have affects on human activities, such as labor productivity, as well as human health. An anthropogenic influence on a summertime heat stress index that includes moisture influences has been detected over global land regions, according to a GFDL study.

Featured Results

• The impact of anthropogenic land use and landcover change on regional climate extremes.
• The Extreme March-May 2012 Warm Anomaly Over the Eastern United States: Global Context and Multimodel Trend Analysis
• Heat stress reduces labor capacity under climate warming
• A Model Study of Heat Waves over North America: Meteorological Aspects and Projections for the 21st Century

Publications

• Findell, K. L., A. Berg, P Gentine, J. P Krasting, B R Lintner, S. Malyshev, J A Santanello, and E. Shevliakova, 2017: The impact of anthropogenic land use and landcover change on regional climate extremes. Nature Communications, 8, 989, DOI:10.1038/s41467-017-01038-w .
• Knutson, T.R., and J. J. Ploshay, 2016: Detection of anthropogenic influence on a summertime heat stress index. Climatic Change, 138(1-2), DOI:10.1007/s10584-016-1708-z
• Knutson, T. R., F. Zeng, and A. T. Wittenberg, 2014: Multimodel assessment of extreme annual-mean warm anomalies during 2013 over regions of Australia and the western tropical Pacific. Section 8 of: “Explaining extreme events of 2013 from a climate perspective.” Bull. Amer. Meteor. Soc., 95 (9), S26-S30. doi: 10.1175/ExplainingExtremeEvents2013.1.
• Knutson, Thomas R., Fanrong Zeng, and Andrew T. Wittenberg, 2013: The extreme March-May 2012 warm anomaly over the eastern United States: global context and multimodel trend analysis [in “Explaining Extreme Events of 2012 from a Climate Perspective”]. Bull. Amer. Meteor. Soc., 94 (9) S13-S17.
• Dunne, John P., Ronald J Stouffer, and Jasmin John, June 2013: Reductions in labour capacity from heat stress under climate warming. Nature Climate Change, 3(6), DOI:10.1038/nclimate1827.
• Lau, Ngar-Cheung, and Mary Jo Nath, July 2012: A Model Study of Heat Waves over North America: Meteorological Aspects and Projections for the 21st Century. Journal of Climate, 25(14), DOI:10.1175/JCLI-D-11-00575.1.
• Delworth, Thomas L., Jerry D Mahlman, and Thomas R Knutson, 1999: Changes in heat index associated with CO₂ -induced global warming. Climatic Change, 43(2), 369-386. DOI: 10.1023/A:1005463917086