As temperatures rise and summer kicks off, it is important to acknowledge that not all Chicagoans experience heat in the same way. Urban heat islands (dense concentrations of buildings and cement that trap heat) experience temperatures 5-7 degrees hotter during the day and up to 22 degrees hotter at night, compared to surrounding areas. The entire Chicagoland area is a heat island when compared to the surrounding suburbs, but there are even heat disparities on the neighborhood level due to lack of greenery and historical disinvestment. Low-income communities of color experience much higher temperatures than more affluent, predominantly white areas within cities.
A 2019 study by Vivek Shandas of Portland State University analyzed summer temperatures in different neighborhoods in major metropolitan areas. In Baltimore, a city with similar population distribution to Chicago, the discrepancy peaked at 13 degrees Fahrenheit. On the hottest day of the year, temperatures in densely populated downtown areas reached 103 degrees. It is no coincidence that these areas, like East Baltimore, are home to predominantly African-American and low-income communities. On the other hand, affluent neighborhoods on the city’s west side like Leakin Park and Ten Hills displayed temperatures as low as 87 degrees Fahrenheit at the same time, on the same day. A 2018 study by environmentalists at Notre Dame also found that roof temperatures in Chicago are 3-5 degrees hotter on the city’s west side than the north side.
These disparities exist because of redlining, disenfranchisement, and other discriminatory practices that have consolidated low-income populations of color into dense urban neighborhoods that trap heat. Subsequent disinvestment in these neighborhoods has only worsened their condition, leaving behind empty lots of asphalt that absorb and radiate more heat. Proximity to major highways and industrial sites adds to these higher temperatures through greenhouse gases and heat radiation. All the while, many cities fail to provide adequate green spaces that could counter these effects.
This is a dangerous health issue. According to CNN, there has been a 74% increase in heat-related deaths since 1980. As global temperatures rise, it is imperative that we improve tree equity in urban environments to preserve the health of these communities. Cities like Portland are proposing regulations that limit new construction to curb the addition of heat-raising concrete and asphalt. However, this will only affect land that interests developers. What can be done to improve tree canopy in areas not suitable for development? According to Lisa McNeily, Director of the Baltimore Office of Sustainability, the city is trying to turn vacant lots into permanent green spaces. The Miyawaki forest planting method that Nordson Green Earth Foundation uses can create tree canopy in an area as small as a few parking spots in just twenty years. This is one of the quickest and most sustainable ways to increase tree equity and in turn, reduce temperatures in urban heat islands—particularly neighborhoods most at risk for heat-related illness and death.
You can check out www.nordsongreenearth.org/projects to see how we are improving tree equity and beating the heat!