Michael Wehner, Federico Castillo, and Dáithí Stone
This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Natural Hazard Science. Please check back later for the full article.
Extremely high air temperatures are uncomfortable for everyone. For some segments of the population, they can be deadly. Both physical and societal aspects of intense heat waves in a changing climate warrant close study. The large-scale meteorological patterns leading to such events create the framework for understanding their underlying causal mechanisms, and several methods of quantifying the combination of heat and humidity can be used to determine when these patterns result in heat waves. Historic heat waves with significant impacts on society reveal the efficacy of statistical methods for measuring heat waves and the differences between descriptive techniques. These events also illustrate the variety of effects of extreme heat on humans, which are characterized in terms of demographic, geographic, and socioeconomic impacts, including mortality and economic ramifications.
Observed weather station data and climate model projections of the future predict an increase in the frequency and intensity of extreme heat waves as the overall climate warms. Large-scale meteorological patterns explain this expected increase, and quantifiable statistics of extreme heat waves allow examination of their human dimensions. Future adaptation strategies may be intentional or unintentional, vary by institutional level (government, private sector), and shape individual decision-making processes. All areas of future research, from both the physical and the social sciences, need to maintain the goal of enabling society to adapt to extreme heat waves.