Everyone is feeling the heat this summer as daytime temperatures skyrocket with heat indexes in the triple digits and the nights stay warm. But heat isn’t evenly distributed across Charlotte’s urban heat island. For the first time, a group of volunteers are tracking down Charlotte’s hottest neighborhoods.
It was 97 degrees Fahrenheit last week when volunteer Sydney Idzikowski started her route, driving for Charlotte Heat Mappers, the coalition of organizations mapping heat disparities throughout Charlotte.
"I was just super excited to be a part of it, to help collect very localized data about heat in our community," she said.
Her co-pilot, Katie Zager, fed her directions, tracing the route mapped on her phone.
"We're gonna kind of go down Graham Street towards I-77 and loop back to our starting place in uptown," Zager said.
A heat sensor took a reading every couple seconds as Idzikowski drove, measuring temperature and humidity along the 18-mile route. Zager clipped the sensor to the passenger-side window before they started, where it stuck up like an upside-down honey dipper. The sensors were provided to Charlotte Heat Mappers by the National Oceanic and Atmospheric Administration (NOAA).
Zager, Idzikowski and about 60 other volunteers were conducting what Idzikowski called “science in motion.”
"We've gotta keep it below 35 miles per hour to make the sensors the most effective they can be," she said. Moments later, a passing car blared its horn.
"Go around me then. Science in motion, honey!" she said.
Charlotte Heat Mappers and NOAA planned these routes ahead of time to cover specific parts of the city. Joe Wiswell, a research assistant at UNC-Charlotte’s geography department talked with community leaders and organizers who helped create a list of important locations to map.
"It can be a park that maybe cools things down, it can be a parking lot that maybe heats things up," he said.
From there, a standardized heat mapping methodology dictates the schedule. Drivers start their routes at 6 a.m., 3 p.m. and 7 p.m.
"The idea is actually throughout the day, things are just going to get hotter," said Katherine Idziorek, leader of the Charlotte Heat Mappers. "Even into the evening, even though we're past the peak temperature of the day, all those surfaces are continuing to radiate heat."
Not all neighborhoods experience the summer heat the same. Lack of tree cover in some and more impervious surfaces like parking lots, buildings and streets drive up the heat.
"There are disparities in temperature, even up to 15, or 20 degrees in some areas across just from one neighborhood to another. So what we don't know is where those disparities are specifically," Idziorek said.
The goal is to create what she calls an international “atlas of heat maps.” Over 60 cities have already been mapped.
Raleigh and Durham participated in 2021. The data helped Raleigh secure funding to plant and maintain trees as well as educate community members about heat preparedness. The maps also helped inform infrastructure choices, as the city seeks to reduce flood impacts in vulnerable communities while keeping temperatures down.
"This will help us to understand in very specific places where we should plant those trees, where we should send those public health resources," Idziorek said.
Idziorek said communities know which of their neighborhoods are hotter, but this project will help “put numbers to those feelings.”
After Idzikowski and Zager finished their route, they turned in their sensor. The readings from their route and from the 30 other teams will help Charlotte plan for a future that grows hotter by the day. NOAA will release the data publicly on heat.gov sometime this fall.
