Take a look: This is deforestation’s footprint from 2000 to 2012, according to a new study of 650,000 high-resolution satellite images.
The world lost the trees on some 2.3 million square kilometers (0.9 million square miles) of land, while trees grew back or were planted on roughly 0.8 million sq km. Here’s what those total land areas would look like in both the US and Europe:
Deforestation at this scale is having a tremendous ecological impact, on both species and climate. From 2000 to 2011, deforestation effectively added 14.5 billion tonnes (16 billion tons) of carbon to the atmosphere, about 13% of the world’s total contribution to climate change.
But good data on worldwide forest loss are hard to come by. Many countries report deforestation on their own soil, but define it in differing ways. In Canada, if a stand of trees is cut down, but the stumps aren’t removed, government scientists do not consider it a loss, because the forest will eventually grow back. A similar definition holds in Indonesia, but not in other countries. This makes it impossible to stitch together a consistent global picture from national figures.
The new deforestation study, led by scientists at the University of Maryland and published online today in the journal Science, uses satellite images to look at the wholesale loss and growth of trees around the world, including clear-cutting to make way for agriculture, logging, and losses from forest fires. And it does it with extreme granularity. The images have a resolution of 30 meters, which means the entire world is divided up into pixels about one eighth the size of a soccer pitch.
The analysis confirms that Brazil, the global capital of deforestation, has had some success in reducing it. From 2004 to 2012, its annual rate of deforestation fell nearly by half, from roughly 40,000 sq km a year to slightly over 25,000. (For this reason, Brazil has the weirdest carbon footprint in the world.)
Meanwhile, Indonesia has been catching up. By 2012, it was cutting down 20,000 sq km of forest a year, nearly the same rate as Brazil, even though Indonesia’s total land mass is less than a quarter of Brazil’s. Here’s an animated gif of forest loss in Indonesia, courtesy of the researchers: