Why This is Important
The average evening temperature helps to measure how susceptible different neighborhoods are to global warming. High temperatures overnight are particularly associated with health impacts of climate change in vulnerable populations, because at night time it is hardest to leave home to find relief in cooler areas.
Heat islands are defined by the Environmental Protection Agency (EPA) as “urban area[s] characterized by temperatures higher than those of the surrounding non-urban area. As urban areas develop, buildings, roads, and other infrastructure replace open land and vegetation. These surfaces absorb more solar energy, which can create higher temperatures in urban areas.”
These “islands” of persistently higher-temperatures make it harder to get relief from a summer day and more likely to be a place of poor air quality and respiratory stress. Knowing what neighborhoods in our community face these distinct challenges can help us mitigate the effects of heat islands by adding green space and trees, while offering other support for households experiencing potentially harmful exposures during peak temperatures.
About the Data
This metric reports the average modeled temperature between 7-8pm on a typical summer day in degrees Fahrenheit across each blockgroup or tract. The temperatures were modeled using a random forest machine learning model, trained on data points collected in July 2021 by Durham volunteers and the Museum of Life and Science as part of the CAPA Heat Watch Program.
Volunteers collected temperature samples throughout Durham which were then used to model temperature variations across the city. More about the project as a whole and data produced by Durham and Raleigh volunteers can be found .
The CAPA study focused on downtown Durham and surrounding neighborhoods; in the Compass this metric omits census areas which had less than 50% of their area included in the study.