Three Ways Cities Can Combat Extreme Heat

According to one study, the number of days in a year across the United States that feel hotter than 100 degrees Fahrenheit will more than double by mid-century. That's bad news for cities designed in ways that often exacerbate urban heat, Adele Peters writes. While broad infrastructural changes (and, ultimately, the elimination of fossil fuels) will do the most to combat an even hotter future, simple mitigation methods do exist for the heat that cities are already feeling.

When it comes to planting urban trees, "There are multiple benefits, but one is simple: As trees shade streets, and water evaporates from their leaves, they cool neighborhoods." Cities like Melbourne, Milan, and Madrid are all engaged in ambitious plans to grow out their urban forests.

Other cities, like New York, Los Angeles, and Tokyo, are covering rooftops and pavements with reflective coating. "The coating helps lower temperatures inside buildings, helping people feel more comfortable and use less air conditioning; like cars, air conditioners are both another major source of emissions and make cities immediately hotter as the machines vent heat outside."

Another way to fight urban heat is to equip structures with "smart" systems like automatic shades and windows programmed to respond to heat conditions, and to choose building materials with heat mitigation in mind. In the end, Peters notes, reducing automobile dependence will also play a role. "Cities that incentivize less driving—whether by redesigning bike lanes and sidewalks or changing codes to make new developments mixed-use and near public transportation—can cool themselves down."