Impacts of Climate Change: Extreme Heat is a Rising Threat to Public Health and an Environmental Justice Issue

Across the world, climate change is causing temperatures to rise and extreme heat events to grow in frequency, severity, and duration. Excessive heat is not distributed evenly in society. Low-income, minority communities experience additional exposure and vulnerability to heat. Equally important, the ability to prepare and respond to heat is uneven, and access to cooling strategies is directly correlated to income and race. According to the EPA, “Environmental justice is the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to development, implementation and enforcement of environmental laws, regulations and policies.” Extreme heat is an environmental justice issue.

Extreme heat events are rapidly increasing. 

2021 was the sixth hottest year on record. In June of 2022, over 75 million people experienced excessive heat across the United States. Soon after, 62 migrants were trapped inside a 170-degree Fahrenheit tractor-trailer in San Antonio, Texas, and 53 died. In July of 2022, a heat wave blanketed Europe, triggering wildfires in France and record-breaking heat in the United Kingdom. Increased heat events are prompting heat-related illness, death, and poor air quality (due to increased ozone pollution and wildfire risk and spread) to climb.

Blue Forest is exploring how conservation finance could support urban  green infrastructure projects.

Blue Forest works to accelerate and scale climate resilience projects using innovative finance and strategic partnership development. In 2021, Blue Forest began exploring how conservation finance tools might be applied in an urban context, especially to support green infrastructure development and build urban climate resilience.  Cities have reported temperatures up to 22 degrees warmer than surrounding areas due to “urban heat islands.” Reduced canopy coverage, in addition to an increase in paved areas and non-reflective surfaces, traps heat between tall buildings and places like parking lots. Urban heat islands contribute to warmer temperatures lingering across urban environments. In a 2019 analysis of US Census data and thermal satellite images, NPR and the University of Maryland’s Howard Center for Investigative Journalism found a relationship between heat and income, with low-income communities experiencing hotter temperatures. The study also found that some warmer, low-income, predominantly African American neighborhoods were consistent with areas redlined by the Home Owners’ Loan Corp in a 1937 map, demonstrating how racist policies leave a legacy of disadvantage and contribute to health inequities.

Exposure and vulnerability to extreme heat are uneven

Other drivers contribute to uneven exposure and sensitivity to extreme heat. Regionally, the Southwestern and Midwestern United States are the most impacted. An additional burden is placed on unsheltered people, outdoor workers (disproportionately Black and Brown people), migrant communities, people living or working without air conditioning, outdoor athletes, and urban communities. People with certain health conditions, including heart disease, mental illness, obesity, high blood pressure, asthma, multiple sclerosis, or chronic obstructive pulmonary disorder, are particularly vulnerable to heat. In addition, pregnant people, infants, children, people over 65, and people actively using drugs or alcohol are more sensitive to excessive heat.

The ability to prepare and respond to extreme heat is associated with income and race

There is inequity in the ability to prepare for and respond to heat. Hydration is key to preventing heat illness. According to Dig Deep and the US Water Alliance, in the United States, over two million people lack access to drinking water and sanitation, and access is strongly correlated with race. In addition to extreme heat, other extreme weather events such as flooding, severe wildfire, and drought threaten water sources. Access to air conditioning and electric fans helps to regulate indoor temperatures and can be the difference between life and death. The upfront cost, maintenance, and power usage of these appliances are expensive and bar many from the ability to cool down. In 2015, nearly one in three Americans reported having difficulty “paying energy bills or sustaining adequate heating and cooling in their homes.” The cost of cooling down contributes to health inequities from extreme heat. As mentioned, exposure to extreme temperatures can require medical attention and lead to chronic illness. Affordable medical care and adequate health insurance are vital for people experiencing extreme heat. As of 2020, 31.6 million Americans lack health insurance, with disparities traced to race and income. Water, power, and healthcare are basic human needs for survival in a world of extreme weather.

Strategies exist to mitigate extreme heat in your community and home

Along with heat exhaustion and heat stroke, extreme heat “can cause excessive damage to all tissues and organs,” triggering cardiovascular collapse and kidney failure, preterm births, underweight babies, crime, anxiety, depression, and death by suicide. Many strategies exist to prevent heat-related illness. In an urban setting, planners can use green finance strategies to build accessible cooling centers, public parks, and blue spaces (such as fountains or public pools) and implement green infrastructure techniques such as planting trees and green roofs and installing cool, reflective, permeable pavements and roofs. It is important to incorporate equity into planning these strategies to avoid “green gentrification,” or the displacement and pricing out of low-income communities in response to green infrastructure projects.  Power utilities can plan for increased demand during extreme heat and schedule extra crews to respond to overheating equipment. School authorities have already begun canceling classes, adjusting dismissal times, and moving to e-learning to reduce students’ heat exposure. Some outdoor workers have started working during pre-dawn hours to avoid the sun. Besides drinking water and using cooling appliances, there are strategies to reduce your exposure and vulnerability to extreme heat, such as closing blinds and avoiding caffeinated and alcoholic beverages. To support your community, check in on your vulnerable neighbors – especially the elderly or people with mobility issues.

Looking Ahead

NOAA has forecasted above-normal heat this summer for the majority of the country. Preparing for and building resilience to extreme heat is essential this summer and in the long term as we adapt to a climate of severe weather. We must acknowledge the disparity in exposure, vulnerability, and ability to prepare and respond to the impacts of climate change and cultivate strategies that empower and support disadvantaged communities. Blue Forest is exploring conservation finance solutions that address climate resilience in an urban context to reduce the urban heat island effect, improve stormwater retention, and sequester carbon. Check out our March 2022 Science Corner written by Tessa Maurer, PhD, to learn more about the intersection of urban forestry and equity. Elsewhere, Blue Forest is also working to reduce the risk of catastrophic wildfires (worsened by extreme heat) through the Yuba I and Yuba II Forest Resilience Bonds on Tahoe National Forest.

How Can You Help? 

• Besides drinking water and using cooling appliances, there are strategies to reduce your exposure and vulnerability to extreme heat, such as closing blinds and avoiding caffeinated and alcoholic beverages.

• To support your community, check in on your vulnerable neighbors – especially the elderly or people with mobility issues.

• Promote green infrastructure projects in your community.

• Check out our March 2022 Science Corner written by Tessa Maurer, PhD, to learn more about the intersection of urban forestry and equity.