Researchers at the University of Pittsburgh Swanson School of Engineering used a Computational Fluid Dynamics model to find ways to decrease cost and increase usage of cooler surfaces.
Researchers at the University of Pittsburgh Swanson School of Engineering used a Computational Fluid Dynamics model to find ways to decrease cost and increase usage of cooler surfaces. The paper, published in the journal Nature Communications, examined the possibility of applying cooler surfaces to just half the surfaces in a city.
If you’ve ever been in a city’s central core in the middle of summer, you know the heat can be brutal—and much hotter than in the surrounding region.
Temperatures in cities tend to be several degrees warmer than in its rural areas, a phenomenon called the Urban Heat Island (UHI) effect. Many cities have been observed to be 2-4ºC warmer than the countryside in virtually every inhabited continent. This phenomenon occurs because urban infrastructure, especially pavements, absorbs a lot of heat as compared to natural vegetated surfaces. This heat pollution causes higher air conditioning and water costs, while also posing a public health hazard.
One mitigation strategy called gray infrastructure involves the modification of impermeable surfaces (walls, roofs, and pavements) to counter their conventional heating effect. Typical urban surfaces have a solar reflectance (albedo) of 0.20, which means they reflect just 20 percent of sunlight and absorb as much as 80 percent. By contrast, reflective concrete and coatings can be designed to reflect 30-50 percent or more. Cities like Los Angeles have already used reflective coatings on major streets to combat heat pollution, although the solution can be expensive to implement city-wide.
Read more at University of Pittsburgh
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