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Abstract Extreme heat events are a threat to human health, productivity, and food supply, so understanding their drivers is critical to adaptation and resilience. Anticyclonic circulation and certain quasi-stationary Rossby wave patterns are well known to coincide with heatwaves, and soil moisture deficits amplify extreme heat in some regions. However, the relative roles of these two factors in causing heatwaves is still unclear. Here we use constructed circulation analogs to estimate the contribution of atmospheric circulation to heatwaves in the United States in the Community Earth System Model version 1 (CESM1) preindustrial control simulations. After accounting for the component of the heatwaves explained by circulation, we explore the relationship between the residual temperature anomalies and soil moisture. We find that circulation explains over 85% of heatwave temperature anomalies in the eastern and western United States but only 75%–85% in the central United States. In this region, there is a significant negative correlation between soil moisture the week before the heatwave and the strength of the heatwave that explains additional variance. Further, for the hottest central U.S. heatwaves, positive temperature anomalies and negative soil moisture anomalies are evident over a month before heatwave onset. These results provide evidence that positive land–atmosphere feedbacks may be amplifying heatwaves in the central United States and demonstrate the geographic heterogeneity in the relative importance of the land and atmosphere for heatwave development. Analysis of future circulation and soil moisture in the CESM1 Large Ensemble indicates that, over parts of the United States, both may be trending toward greater heatwave likelihood.
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Sociodemographic Factors Associated with Heatwave Risk Perception in the United States
Abstract Extreme heat events are one of the deadliest weather-related hazards in the United States and are increasing in frequency and severity as a result of anthropogenic greenhouse gas emissions. Further, some subpopulations may be more vulnerable than others because of social, economic, and political factors that create disparities in hazard impacts and responses. Vulnerability is also affected by risk perceptions, which can influence protective behaviors. In this study, we use national survey data to investigate the association of key sociodemographic factors with public risk perceptions of heatwaves. We find that risk perceptions are most associated with income, race/ethnicity, gender, and disability status. Age, an important predictor of heat mortality, had smaller associations with heat risk perceptions. Low-income, nonwhite, and disabled individuals tend to perceive themselves to be at greater risks from heatwaves than other subpopulations, corresponding to their elevated risk. Men have lower risk perceptions than women despite their higher mortality and morbidity from heat. This study helps to identify subpopulations in the United States who see themselves as at risk from extreme heat and can inform heat risk communication and other risk reduction practices.
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- PAR ID:
- 10425637
- Date Published:
- Journal Name:
- Weather, Climate, and Society
- Volume:
- 14
- Issue:
- 4
- ISSN:
- 1948-8327
- Page Range / eLocation ID:
- 1119 to 1131
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1175/WCAS-D-21-0104.1
