You probably don’t know this, but Louisville, Ky., is an island. Yes, you read that correctly.
Granted, Louisville is not a real island, but it’s an urban heat island — a phenomenon where a city’s center is much hotter than its surrounding areas. Due to the abundance of darkly paved areas, the heat is stored and released throughout the day and night, which prevents the area from cooling down after sunset. While this doesn’t cause pollution, it does heighten the effects.
“Cities essentially create their own climates,” urban heat expert Brian Stone Jr. explains to Politico. “And the urban heat island effect is one way to measure that. There’s a heat island effect, really, in every large city.”
With an urban core that’s 20 degrees warmer than the surrounding area, Louisville ranks as the number one heat island in the nation — resulting in higher electric bills for residents, more coal burned, disruptions in the city’s ecosystem because of hotter storm water and even death by heat. And while this designation isn’t something to be proud of, the city’s effort to reverse it is.
In 2012, there were 39 heat-related deaths, which spurred the city into action. Louisville created a tree commission to assess and revive trees that were damaged by natural disasters because it believes that it’s imperative to maintain and replace existing trees in addition to planting new trees. Plus, it has spent $115,000 on tree assessments, received $135,000 in grants to study the urban heat island (the first ever in its kind) and planted over 12,000 trees since 2011.
Louisville has also hired a director of sustainability and an urban forester to address the present and the future. Local nonprofits are also getting involved in the solution. Louisville Grows holds volunteer planting days where the group plants trees across the downtown. And the nonprofit American Forests assessed the approximate percentage of trees needed to combat the urban heat island, which stands at about 20 percent in the downtown area, but Louisville only has about eight percent, reports Politico.
“It’s really important to us that while we’re planting the trees,” Louisville Grows executive director Valerie Magnuson says. “We’re thinking in terms of a tree that’s going to be living for 100 years or much longer, and is going to carry on after we’re all gone.”
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