📖 Rethinking Urban Heat

Cities are often several degrees warmer than surrounding countryside, a phenomenon known as the urban heat island effect. Dark asphalt and rooftops absorb sunlight during the day and release heat slowly at night, while buildings block cooling breezes.

The consequences are significant. Higher temperatures increase energy demand for air conditioning, worsen air quality and pose serious health risks during heat waves, particularly for older adults and people without access to cooling.

Cities are responding with a range of strategies. Planting trees provides shade and cools the air through evaporation. Reflective “cool roofs” bounce sunlight back into the sky, and lighter-colored pavements absorb less heat.

Researchers caution that solutions must be distributed fairly. Lower-income neighborhoods often have fewer trees and more pavement, so the benefits of cooling projects should reach the communities most at risk.