In grade school, we all learned that white reflects heat and black absorbs it. There would always be that one kid on the playground who would chide you for wearing a black shirt on a hot day. Did you listen to that kid? Probably not. He seemed weird with his white shirt and Square One lunch box, but he was actually ahead of his time.

The science behind grade-school shirt-wearing can be used to fight global warming, and we don't even have to change our wardrobes. We only have to change our roofs. Roofs account for about one quarter of a city's surface area. Pavement accounts for over one third. These two surfaces absorb a lot of heat.

By replacing dark-colored roofs and pavement with reflective alternatives, we can offset 44 metric gigatons of greenhouse emissions annually. If you own a small home with a small roof, 500 square feet, and you replace dark shingles with reflective, white shingles, you can offset 5 metric tons of greenhouse gases per year. That's a lot of greenhouse gas for just one person. You can also just paint your roof white to achieve the same effect.

Another way to offset greenhouse gases is by using concrete instead of asphalt. Concrete doesn't use petroleum products, and it is more reflective than asphalt. A white roof and a concrete driveway are two small ways to fight global warming.Live green under a white roof.

Live green under a white roof.