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7 ways humans are damaging the planet

By: Katherine Butler on Sept. 5, 2012, 5:56 p.m.
Amazon deforestatation

Photo: NASA

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Epic deforestation

In the past 40 years, as much as 20 percent of the Amazon rain forest has been cut down. The rain forest produces half of its own precipitation. As the forest is destroyed and burned for industrial purposes, the remaining trees dry out and die. This activity has made Brazil one of the largest greenhouse gas emitters on the planet.

Pictured here is the state of Rondônia in western Brazil as imaged by NASA’s Terra satellite. This 51.4 million acres of forest was once roughly the size of Kansas, according to NASA, but now it is on track to becoming the most deforested part of the Amazon.

How bad is it? NASA reports that 4,200 square kilometers [of land had been] cleared by 1978; 30,000 by 1988; and 53,300 by 1998. By 2003, an estimated 67,764 square kilometers of rain forest — an area larger than the state of West Virginia — had been cleared. Here we see the area in 2000 (left) and 2010.