Thanks to climate change, the Arctic is turning green
By Chris Mooney Energy and EnvironmentJune 27
Using 29 years of data from Landsat satellites, researchers at NASA have found extensive greening in the vegetation across Alaska and Canada. Rapidly increasing temperatures in the Arctic have led to longer growing seasons and changing soil for plants. (Cindy Starr/NASA’s Goddard Space Flight Center)
Earlier this month, NASA scientists provided a visualization of a startling climate change trend — the Earth is getting greener, as viewed from space, especially in its rapidly warming northern regions. And this is presumably occurring as more carbon dioxide in the air, along with warmer temperatures and longer growing seasons, makes plants very, very happy.
Now, new research in Nature Climate Change not only reinforces the reality of this trend — which is already provoking debate about the overall climate consequences of a warming Arctic — but statistically attributes it to human causes, which largely means greenhouse gas emissions (albeit with a mix of other elements as well).
[Alaska’s huge climate mystery, and its global consequences]
The roughly three-decade greening trend itself is apparent, the study notes, in satellite images of “leaf area index” — defined as “the amount of leaf area per ground area,” as Robert Buitenwerf of Aaarhus University in Denmark explains in a commentary accompanying the study — across most of the northern hemisphere outside of the tropics, a region sometimes defined as the “extratropics.” Granted, there are a few patches in Alaska, Canada and Eurasia where greening has not been seen.