If you find the summer heat hard to take, cities are the worst places to be. Studies show that urban spaces can be up to three degrees hotter than surrounding areas. That's because of the "heat island effect"—which is what you get from paving every available surface with heat-absorbing asphalt and concrete.
Lamm snapped these images with a thermal camera on a five-hour whirlwind trip from Pittsburgh (which he talks about here). He teamed up with John Frederick, a heat island expert at the University of Chicago, who explained exactly why some parts of the city are hotter than others (see the slide show for more information on that).
All this heat we're trapping isn't merely an uncomfortable inconvenience. Each extra degree adds to air conditioning bills and increases energy consumption; it also raises health risks for the elderly and vulnerable. Painting more roofs white would help, as would more trees. Cities should also think about new colors for pavements, as we discussed here.