Urban Heat Island Temperature Mapping Campaign

Raleigh and Durham – 2021

Hot days create physical stress for people and can be hazardous to the elderly, the young, people with pre-existing medical conditions, and those working outdoors. Some areas are also experiencing increases in nighttime minimum temperatures, which can be particularly hazardous for people without adequate cooling in their homes.

In urban settings, hot days can be amplified by the lack of tree canopy cover and the increase in dark surfaces with a low albedo, such as roads and buildings. Vulnerable communities are at greater risk for heat-related illness during times of intense and/or prolonged heat.

Making cities cooler can involve a variety of actions, such as opening more public air-conditioned spaces; removing or whitewashing large areas of black asphalt or dark roof surfaces (low albedo surfaces); adding more trees for shade; and engaging in urban design to increase natural airflow through hot neighborhoods.

What about Raleigh and Durham?

Raleigh and Durham are the 2nd and 4th largest cities in NC respectively, and together make up one of the fastest growing urban areas in the country.

With accelerated growth comes sprawl and urbanization. Raleigh and Durham are experiencing double the number of days over 95 ̊F than in the historical past. The NC Department of Public Health (NCDPH) releases weekly heat reports documenting emergency room visits related to heat and proactively encourages safety when extreme heat is forecasted. NCDPH estimates about 3000 ER visits are made for heat each year; in 2019, the total was near 4000 by the end of August.

The first step to address heat islands is to collect specific data on the temperature variations across Raleigh and Durham, especially in developed urban core areas. Populations living in our heat islands are likely suffering from negative health outcomes and heat-related illnesses (click here to learn about excessive heat and safety!). There are also benefits to addressing urban heat islands regarding climate equity and community resilience.

The UHI campaign supports the work of The Triangle Regional Resilience Partnership Resilience Assessment that was prepared for the Triangle region, including Raleigh and Durham by UNC Asheville’s National Environmental Modeling and Analysis Center in October 2018 that highlights two heat related climate change threats to this region of increasing temperatures, and the frequency and duration of drought conditions. Raleigh has also just completed a Community Climate Action Plan that includes community- wide strategies and actions to address climate change, reduce greenhouse gas emissions, and community resilience while addressing climate equity and environmental justice. The heat island data will be important in the work to mitigate urban heat islands and adapt to climate change.