Following multiple record-breaking heatwaves this summer, the U.S. House of Representatives Committee on Science, Space, and Technology held its first-ever hearing on extreme heat. This marks a positive step for the U.S. to seriously and immediately address heat as the nation’s most deadly climate risk.
The Pacific Northwest heatwave in June 2021 was a mass casualty event, estimated to have caused around 600 deaths in Oregon and Washington alone. These extreme heat events are increasingly more frequent, longer in duration and more intense due to climate change. They are also compounded by the urban heat island (UHI) effect, where urban areas are hotter than surrounding rural and natural areas due to how cities are planned, built and operated.
Yet, the national perception of heat as a climate risk remains subdued compared with more visually dramatic hurricanes or wildfires. Heat is a silent and invisible killer and impacts the most marginalized and vulnerable communities. Heat also has real impacts and costs to infrastructure, economic productivity, vegetation and wildlife, and energy and water use.
Over the past year, our coverage of heat equity has focused mainly on the inequitable distribution of heat severity in the urban heat island effect in cities across the U.S. — revealing how the hottest land surface temperatures tend to be in the poorest communities and communities of color. However, individuals experience personal heat exposure throughout their day, not just at home, but also during transportation and at work and school.
The COVID-19 pandemic has revealed how the compounded and systemic heat inequities extend to many issues, including access to health care, quality housing, water and energy for indoor cooling. Heat risk is particularly high for the elderly, children and those with health conditions, like high blood pressure and breathing difficulties. Chronic diseases like diabetes and lung, heart and kidney disease can also be worsened by heat exposure.
An analysis of early mortality data from the Pacific Northwest heatwave in Portland, Ore., suggests that the majority of deaths occurred in poorer parts of the city. In Seattle, the elderly and people experiencing homelessness were particularly harmed by the heatwave. During these heatwaves, low-income residents often have a difficult time affording crucial indoor cooling and getting transport to cooling centers.
Chronic heat exposure particularly impacts people experiencing homelessness, those without adequate indoor cooling, those unable to pay for utilities and those who work outdoors. A significant number of heat-related deaths throughout 2020 in Phoenix occurred among homeless senior citizens experiencing homelessness. People experiencing homelessness are vulnerable to all forms of heat exposure and are difficult to reach with early warning systems and information about the location of cooling centers.
Increasing homelessness has been exacerbated by the COVID-19 pandemic, the housing affordability crisis and an estimated shortage of 3.8 million housing units. It should come as no surprise that a disproportionate share of those experiencing homelessness are Black and Latinos, who also represent some of the hardest-hit communities by the pandemic and live in the hottest neighborhoods in urban areas.
Although the Centers for Disease Control and Prevention (CDC) recently extended the federal eviction moratorium, policies regarding the utility shutoffs vary by state, with some states extending the moratorium to keep utilities on, and others electing not to. Many Americans behind in their housing payments are awaiting rental relief that has been allocated but not yet dispersed.
To better address heat as a national risk, we need more integrated local efforts and increased and coordinated national support. With the exception of the city of Phoenix, which created an Office of Heat Response and Mitigation, and Miami-Dade County, which appointed a chief heat officer this year, there is no “problem owner” for heat in the other 35,879 local governments in the U.S. While more cities are beginning to address heat, these efforts are most often siloed between disciplines and levels of government.
Urban planners are largely responsible for heat mitigation, or efforts to mitigate the urban heat island effect caused by the design of the built environment and waste heat. These include strategies such as increasing urban greening, reducing waste heat and integrating heat considerations into urban design and land use planning.
Heat management, or efforts to plan, prepare and respond to heat, is largely the purview of public health and emergency management. These strategies include improving early warning systems, increasing public awareness and education, decreasing personal heat exposure through workplace safety regulations and modifications to outdoor activities, and ensuring accessible and affordable indoor cooling at work, home and school.
As shown by the Pacific Northwest heatwave this summer, no location in the U.S. can delay addressing heat as a risk any longer. Current heat mitigation and management efforts vary greatly by local government capacity and resources. While larger, more well-resourced cities are beginning to make progress addressing heat, smaller and medium-sized communities are at serious risk of falling behind.
In addition, support should be increased for federal initiatives like the National Integrated Heat Health Information System (NIHHIS), a jointly developed program by the CDC and the National Oceanic and Atmospheric Administration (NOAA), which brings together researchers, experts from a variety of federal agencies, and local decision-makers to improve evidence-based heat efforts. NIHHIS is well-positioned to assist communities of diverse geographies and sizes to address heat as a deadly national climate risk.
Ladd Keith is an assistant professor of planning and chair of sustainable built environments in the School of Landscape Architecture and Planning at the University of Arizona. Follow him on Twitter @laddkeith.
Andrea K. Gerlak is a professor in the School of Geography, Development, and Environment and interim director of the Udall Center for Studies in Public Policy at the University of Arizona. She is a Tucson Public Voices fellow with the OpEd Project.