By Cameron Williams
Charlotte is hotter than it should be.
But steps are being taken to change the reality.
An analysis by the Smart Surfaces Coalition found areas in the city with an abundance of dark surfaces like roofs, roadways and parking lots are an average of 14 degrees hotter than areas with green space. The Smart Surfaces Coalition is a non-profit organization whose goal is to help cities lower their average temperature, which in turn lowers energy bills and allows people to live more comfortably. The coalition is partnering with Charlotte.
“What motivated us to create this is that cities are getting hotter and hotter,” coalition CEO and founder Greg Kats said. “This is not just because of climate change, but because they’re covering themselves in dark surfaces and more people. Also, as populations grow, you’re paving over green areas, so there’s more flooding, and that results in mold. You’re seeing it in an uptick in asthma and allergies among kids, so it’s got this huge range of bad outcomes in our cities to have tons of dark surfaces.”
The coalition’s survey of Charlotte found approximately 294,000 roads, 5,644 lane-miles of city roads and 1,200 acres of parking lots – impermeable surfaces that absorb up to 95% of the solar radiation and causes temperatures to increase. Heather Bolick, the city’s chief resilience and sustainability officer, said Charlotte is integrating smart surfaces into new construction.
“In our sustainable facilities policy, it requires all of our new construction, all of our roof replacement projects, to have smart surfaces,” she said. “So, all of our roof replacements have what we call smart roofs. The roofs are white reflective surfaces. … We also have requirements around having native vegetation around our buildings. We have concrete, which is also a reflective material, so all of those different things are a part of the city’s policies moving forward.”
What this means for you
By getting rid of tarmac and other types of dark surfaces, it can reduce average temperatures by 3.1 to 6.6 degrees.
“Working with the Smart Surfaces Coalition has allowed us to further our progress toward meeting the city’s sustainability goals, as outlined in the Strategic Energy Action Plan Plus,” Mayor Vi Lyles said in a statement. “This work is critical, especially for our most vulnerable communities, and it is energizing to collaborate with a group equally as passionate about preserving our environment.”
The Strategic Energy Action Plan also focuses on preserving tree canopy, which is proven to help lower average temperature and energy bills. The presence of trees – and mitigation of extreme temperatures – are more prevalent in upper income neighborhoods.
“When you put in trees as part of this strategy, you’re obviously getting a lot more rainfall that’s captured and doesn’t run off, that’s going into the ground,” Kats said. “It’s keeping up the water table so that the trees can access water. Also, the shade from the trees – if you walk out of the shade in a tree and back in again on a sunny day, it’ll feel 10 to 12 degrees different. It really matters in terms of comfort for pedestrians.”
Bolick added that planting trees by roads also go a long way in mitigating heat.
“There are continued efforts to preserve and also require trees in the right of way.” she said, “We’ve actually seen a few different heat maps, and they’re all saying the same thing, which is obvious: that where you have transportation and roads is really where you have the heat. By keeping those street trees maintained and healthy, that’s really where you’re going to see the reduction in heat.”
