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Just a Fraction More White Roofs Could Have a Huge Global Impact

Small improvements in roof and road reflectivity are estimated to help create big reductions in carbon emissions.
relates to Just a Fraction More White Roofs Could Have a Huge Global Impact
Reuters

If you combined all of the world's urban areas into one dense nugget of urbanity, it would cover about 2 million square kilometers, or 1.3 percent of the land area of the planet. About 60 percent of that – roughly the size of California and Texas combined – is made up of pavement and rooftops.

These roads and roofs can be problematic surfaces. Often dark in color, they soak up sunlight, increasing the temperature of the building and surrounding area in what's known as the urban heat island effect. This in turn contributes to a vicious cycle: the hotter a city feels, the more we energy we tend to use to cool it down, which leads to more greenhouse gas emissions, which contribute to climate change, and so on.