​The World Lost an Oklahoma-Sized Area of Forest in 2013, Satellite Data Show

Russia and Canada's forests are going up in flames, and climate change threatens to make it all worse.

Apr 2 2015, 4:35pm

The regions in North America with more than 30 percent forest loss. 

Oklahoma spans an area in the American South that stretches across almost 70,000 square miles. That's almost exactly the same area of global forest cover that was lost in a single year, back in 2013. And it's perhaps a useful way to visualize the ongoing loss of worldwide forest habitats—recall that in the first decade of the 21st century, the planet lost ​8 percent of its pristine forests.

High resolution maps from Global Forest Watch, tapping new data from a partnership between the University of Maryland and Google, show that 18 million hectares (69,500 square miles) of tree cover were lost from wildfires, deforestation, and development the year before last. The maps were created by synthesizing 400,000 satellite images collected by NASA's Landsat mission.

The big surprise is the huge amount of forest loss in Canada and Russia. While Indonesia, long a global leader in deforestation, finally slowed its rate of destruction, northern boreal forests in Russia and Canada were literally burning up. Between 2011 and 2013, Russia and Canada jointly accounted for 34 percent of worldwide forest loss, according to the data.

Here's an interactive map, which you can use to examine the scale of forest loss around the world: 

Most of that boreal destruction was the result of wildfires, which is a grim portent for our climate-changed world. Scientists expect wildfires to become more frequent as warmer temperatures afflict forested regions. Certainly, they have swept the globe at alarming scale in recent years. And that presents something of a feedback loop: forests are huge carbon sinks, and losing them means we'd expect a surge global greenhouse gas emissions—meaning, perhaps, more fires.

The loss leader was Russia, which saw 4.3 million hectares of forest disappear in a single year, felled by Siberian wildfires. That's nearly twice the loss seen in Canada, at 2.5 million hectares. Brazil (2.2 million hectares), the US (1.7 million hectares), and Indonesia (1.6 million hectares) also saw startling levels of tree cover loss. 

The World Resource Institute, which coordinates Global Forest Watch, notes that the loss is both of the permanent, human-driven variety—razing for agriculture and development—and the cyclical; from fires, logging, harvesting, and natural tree death. In the case of the latter, forests can take decades to be restored. In the former, they're gone for good.

"This new data shows in detail how Russia and Canada have faced a massive spike in tree cover loss," said Dr. Nigel Sizer, the global director, of WRI's forest program. "These forests and soils contain vast carbon stocks so losses represent a significant contribution to the greenhouse gas emissions that are driving climate change."

Losing an Oklahoma-sized area of forest each year, isn't merely a detriment to the local habitats losing their tree cover—it's an increasingly serious threat to the global climate.