The Roof, the Roof...

When the Spaniards discovered Mexico City in 1519, boy, they were surely surprised. They found an ecological marvel: for nearly 200 years the Aztecs had created and honed what was essentially a floating city in a giant riverbed. There were even gardens on the water where the natives grew staple foods like squash and corn.

But you would have never guessed it today, for Mexico City is one of the most polluted on the globe. Mayor Marcelo Ebrard is hoping to dig up some of the city’s ecological history to set a green example for the rest of the country—and maybe even the entire world. As part of a plan to cut the city’s carbon emissions by 4.4 million tons a year, Ebrard has announced that the city will clear away water tanks, clotheslines and asphalt on city-owned buildings to make way for gardens, grass and bushes.

But not just anywhere…these lush grassy areas will be on the roofs of buildings in the city to soak up some of the carbon dioxide released from cars and factories. This is one of the main causes of climate change, according to the U.S. Environmental Protection Agency. The government will also encourage private citizens to follow the trend.

In a city without much grass, these rooftops will also provide an area for children to play. A fix that helps not one good cause, but two? Sounds good to us! [Reuters]