Extreme heat causes more deaths in the United States than all other weather-related causes combined. In a warming climate, health impacts are on the rise, especially in cities, which are warming at a faster rate than non-urban areas. Reducing urban heat exposure is an equity issue, as low-income communities and communities of color are more likely to live in neighborhoods with older buildings, low tree cover, more heat-retaining surfaces, and limited access to coping strategies such as air conditioning. In Los Angeles, the three groups expected to see the largest increases in mortality as L.A.’s climate heats up are the elderly, African Americans, and Latinos. We analyzed meteorological data for four historical summer heat waves against mortality data to determine the numbers of excess, heat-related deaths that occur due to common heat waves in Los Angeles. We then explored the effects that various land cover prescriptions would have on reducing temperature heat and heat-related deaths. We found that roughly one in four lives currently lost during heat waves could be saved, largely in low-income communities and communities of color. We also found that climate change-induced warming could be delayed approximately 25 to 60 years under business-as-usual and moderate mitigation scenarios, respectively. We discuss implications for heat mitigation at the neighborhood, city, and regional level, and present approaches from around the world for how to advance heat mitigation.

Eisenman, David
Sheridan, Scott
Kirner, Kimberly
Maas, Regan
Shickman, Kurt
Fink, David
Parfrey, Jonathan
Chen, Yujuan