Humans as Sensors: The Influence of Extreme Heat Vulnerability Factors on Risk Perceptions Across the Contiguous United States

Extreme heat events are the deadliest natural hazard in the United States and will continue to get worse in the coming years due to the effects of climate change. As a result, more people will experience deadly heat conditions. This highlights the need for decision-makers to develop better strategies for preventing future losses. How badly individuals are affected by extreme heat depends on many circumstances, such as how high temperatures actually are, weather conditions, and location. For example, a dry 90 °F day in Phoenix is probably more tolerable than a humid 90 °F day in New Orleans for most individuals. However, some groups of people are more likely to be harmed by extreme heat than others, such as the elderly and those who work outdoors. This may seem straightforward, but uncovering less obvious clues that help explain how and why some groups are affected differently by extreme heat can be difficult, since much of the impact of extreme heat depends on people’s judgements of the risk and their personal decisions. These human factors are typically not very easy to measure because different hazards affect different people indifferent ways at different times in different places. This study uses a large survey of the U.S. population and statistical methods to explore how weather, time, space, and personal experience with heat affect different people’s judgment of risk. Whether different groups understand their high or low risk status has important implications for decision-makers responsible for crafting plans to reduce extreme heat risk in their local community