How Climate Change Is Growing Forests in the Arctic
If there’s a single lesson for early 21st century life on the planet Earth, it’s this: everything connects. That’s true whether we’re looking at the global economic system, in which sickness is now spreading from the euro zone to China to a wobbly U.S., or the global environment, as we can see in a new study showing the Arctic rapidly responding to climate change by sprouting sudden trees in the tundra.
Researchers in Britain and Finland studied an area of 38,600 sq. mi. (100,000 sq km) in what’s known as the northwestern Eurasian tundra, which stretches from western Siberia to Finland. Surveys of vegetation in the region using both satellite data and local observations from reindeer herders showed that in 8% to 15% of the territory, willow and alder shrubs had grown into trees over 6.5 ft. (2 m) tall over the past 30 to 40 years. That’s a period of time when temperatures in the Arctic have increased significantly, even faster than in other parts of the planet.
As Andrew Revkin of Dot Earth puts it, warming has led to “pop-up forests” in regions of the planet that usually see little more than summer shrubs. That’s a sign of just how fast the Arctic in particular can respond to global environmental change. And as the Arctic greens, it could speed warming even more as the darker foliage absorbs sunlight that would have been reflected back into space by the white tundra. While short shrubs can be covered completely in snowfall — thus reflecting sunlight — tall trees are usually above the white.
The advance of forest into the Arctic could increase Arctic warming by as much as 1° to 2°C by the end of the 21st century. In a statement, Dr. Marc Macias-Fauria of Oxford University — and the lead author on the paper — noted how unusual the advance of Arctic forest was:
It’s a big surprise that these plants are reacting in this way. Previously people had thought that the tundra might be colonized by trees from the boreal forest to the south as the Arctic climate warms, a process that would take centuries. But what we’ve found is that the shrubs that are already there are transforming intro trees in just a few decades.
The planet is changing, and the Arctic is a bellwether of that change. And what happens there will affect us.
Bryan Walsh is a senior editor at TIME. Find him on Twitter at @bryanrwalsh. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.
Read more:http://ecocentric.blogs.time.com/2012/06/04/how-climate-change-is-growing-forests-in-the-arctic/#ixzz21AwjkbzR
How Climate Change Is Growing Forests in the Arctic
If there’s a single lesson for early 21st century life on the planet Earth, it’s this: everything connects. That’s true whether we’re looking at the global economic system, in which sickness is now spreading from the euro zone to China to a wobbly U.S., or the global environment, as we can see in a new study showing the Arctic rapidly responding to climate change by sprouting sudden trees in the tundra.
Researchers in Britain and Finland studied an area of 38,600 sq. mi. (100,000 sq km) in what’s known as the northwestern Eurasian tundra, which stretches from western Siberia to Finland. Surveys of vegetation in the region using both satellite data and local observations from reindeer herders showed that in 8% to 15% of the territory, willow and alder shrubs had grown into trees over 6.5 ft. (2 m) tall over the past 30 to 40 years. That’s a period of time when temperatures in the Arctic have increased significantly, even faster than in other parts of the planet.
As Andrew Revkin of Dot Earth puts it, warming has led to “pop-up forests” in regions of the planet that usually see little more than summer shrubs. That’s a sign of just how fast the Arctic in particular can respond to global environmental change. And as the Arctic greens, it could speed warming even more as the darker foliage absorbs sunlight that would have been reflected back into space by the white tundra. While short shrubs can be covered completely in snowfall — thus reflecting sunlight — tall trees are usually above the white.
The advance of forest into the Arctic could increase Arctic warming by as much as 1° to 2°C by the end of the 21st century. In a statement, Dr. Marc Macias-Fauria of Oxford University — and the lead author on the paper — noted how unusual the advance of Arctic forest was:
It’s a big surprise that these plants are reacting in this way. Previously people had thought that the tundra might be colonized by trees from the boreal forest to the south as the Arctic climate warms, a process that would take centuries. But what we’ve found is that the shrubs that are already there are transforming intro trees in just a few decades.
The planet is changing, and the Arctic is a bellwether of that change. And what happens there will affect us.
Bryan Walsh is a senior editor at TIME. Find him on Twitter at @bryanrwalsh. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.
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