Sub-Arctic Greens as Climate Change Sends Plants North

While some areas became wetter and greener, others dried out with less plant growth since 1982.

A dramatic greening is in progress in high latitudes of the Northern Hemisphere as a warming climate allows vegetation to grow much farther north, researchers say.

A NASA-funded study of satellite and surface observations over the past 30 years shows that the environment in many sub-Arctic regions is now more like what areas 250 to 430 miles to the south experienced in 1982.

“Higher northern latitudes are getting warmer, Arctic sea ice and the duration of snow cover are diminishing, the growing season is getting longer and plants are growing more,” said Ranga Myneni of Boston University's Department of Earth and Environment.

The northern greening is most noticeable in the increased abundance of tall shrubs and trees growing in areas that were recently far too harsh in winter for them to survive.

But the greening is not uniform. Researchers say some boreal zones are becoming warmer and wetter, prompting the growth, while others have become warmer but too dry to support a proliferation of new growth.

And the study reveals that the greening was greater between 1982 and 1992 than it was over the past 20 years.

The study predicts that by the end of this century, northern Sweden could experience temperatures currently more common in southern France, making the sub-Arctic landscape there warm enough to grow grapes.

Graphic: NASA's Goddard Space Flight Center Scientific Visualization Studio