Buckling roads and melting streetcar cables during the record high temperatures in the Pacific Northwest illustrate that “heat wave” is a buzz word this summer, and scientists blame climate change. The heat waves exacerbate the urban heat island effect, in which city temperatures are several degrees hotter than their surrounding areas largely due to manmade infrastructure like buildings and roads absorbing and re-emiting the sun's heat. Many cities aren’t sitting idly by: They’re implementing cooling measures to improve health, safety, resilience and livability.

Recent research on urban heat islands has brought increased awareness to the effects it has on residents and wildlife, its ties to climate change and the actions that could help cities lessen the hazards.

Bangor, Maine; Chicago; Denver; and Portland, Oregon are among the slew of cities turning to the short-term solution of setting up cooling centers to offer residents relief during heat waves and reduce the risk of excessive heat-related health incidents. But cooling centers don't reduce a city's heat intensity. Many cities are implementing long-term strategies to reduce the urban heat island effect by rethinking and reworking future development and adding natural or built infrastructure to cities: trees and green spaces, green roofs, reflective "cool roof" coatings and "cool pavement."

In 2015, Los Angeles tested a light gray pavement coating on a city parking lot that reflects more sunlight than dark asphalt. The cool pavement absorbs less heat to keep street surface temperatures cooler, sometimes by dozens of degrees. After launching another pilot in 2017 in residential neighborhoods, L.A. saw surface temperatures drop 10-20 degrees in areas with the cool pavement.

Read the full article about urban heat islands by Katie Pyzyk at Smart Cities Dive.