Urban Heat Equity - An American Forests Data Short

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Urban Heat Equity

Who lives in urban heat islands in America?

An American Forests Data Short

3 minute read

Aerial view of Baltimore. Image: Jon Bilous / American Forests

Across America, extreme heat disproportionately impacts folks of color and folks in poverty.

American Forests analyzed surface temperature data from thousands of satellite images nationwide. We investigate how urban heat disparities play out in every urbanized¹ neighborhood in America—looking city by city.

In Detroit, more people of color and people in poverty live in the hottest neighborhoods of the city. The trend occurs in cities across America.

A hot day at the city fountain. Image: Svetlana Lazarenka / American Forests

In fact, very few cities in America are exempt from the issue of heat inequity.

An eye-popping 92% of U.S. cities¹ have more residents of color and higher poverty rates in the hottest neighborhoods. The data reveal a pervasive pattern impacting nearly every city in America.

Extreme Heat and People of Color in U.S. Cities

Extreme Heat and Poverty Rates in U.S. Cities

Trees can help moderate heat in your city.

People living in cities are experiencing extreme heat more and more regularly. Climate change is leading to higher temperatures and longer, more intense and more frequent heat waves. Establishing adequate tree cover on a city block can provide up to 10 degrees of cooling.

Check out this story on urban heat islands to learn more.

Ready to plant trees to alleviate heat and heat impacts in your city?

TreeEquityScore.org

Learn More

Tree Equity Score is a free, human-centered, decision-making tool for urban tree plantings used by urban foresters, land-use planners, government officials, neighborhood organizations and many others.

Help make the case for investment in neighborhoods with the greatest need across America using a single, nationwide, neighborhood-level score. Learn more at TreeEquityScore.org

Methods

American Forests' Tree Equity Score is an analysis of urban neighborhoods, where neighborhoods are defined as Census Block Groups, and urbanized areas

are defined by the Census Bureau as “densely developed territory… encompass[ing] residential, commercial, and other non-residential urban land uses.”

Surface temperature data were derived from USGS Earth Explorer

Landsat 8 imagery thermal bands. City¹ averages were calculated as the area-weighted mean of all block group mean summer high surface temperatures. Block groups were flagged as a heat anomaly if the mean summer high surface temperature was 1.25 degrees greater than the area-weighted mean for the city.

For each city, the people of color population and poverty rates were calculated city-wide (all block groups) and for just the block groups flagged as a heat anomaly. People in poverty is a Census measure defined as the percentage of the population with an income less than 200% of federal poverty level. People of color is defined as all people who identify as not white and non-Hispanic or Latinx. The difference between the citywide and heat anomaly values were labeled as "∆ in people of color" and "∆ in poverty rate."

¹Cities were defined as Census Urbanized Area (UA)

units. The Census defines an UA as a continuously built-up area with a population of 50,000 or more, comprising one or more places—central place(s)—and the adjacent densely settled surrounding area—urban fringe—consisting of other places and nonplace territory. The Census Bureau generally merges contiguous urbanized areas when major portions of the urbanized area territories are located in the same metropolitan area (defined by the Federal Office of Management and Budget (OMB) as a core area containing a large population nucleus, together with adjacent communities that have a high degree of economic and social integration with that core area).

Data

Tree Equity Score, 2022.

Story Credits

Article and visuals by Julia Twichell.

This American Forests data short was made possible by funding from

1220 L Street, NW, Suite 750
Washington, DC 20005
Phone: 202.737.1944
Fax: 202.737.2457

Tree canopy data provided
by EarthDefine.