One of the first things I noticed about Belgrade when I arrived there in 2001 was the tall, leafy trees all along the sidewalks. Even when the weather was hot, walking on the sidewalk was still pleasant because of the trees. And this is true in many European cities.

While these trees take time to grow, there are a great many such strategies that can make our cities cooler, and the Smart Surfaces Coalition has a long list. Things like cool roofs offer a very quick payback; other ideas like solar PV roofs, green roofs, and porous and high albedo pavements might take a little longer.