We are actually faster. Tundra to forest in 50 years:
===========================
Warming Arctic Tundra Producing Pop-Up Forests
By
Andrew C. Revkin June 3, 2012 1:02 pmJune 3, 2012 1:02 pm
In the northernmost foothills of the Polar Ural mountains on the southern Yamal Peninsula in West Siberia, Russia, tundra shrubs are turning into small trees, with big implications.
. . .
In this part of the Arctic, which could be a bellwether for changes to come elsewhere with greenhouse-driven warming, what might be called pop-up forests are forming. Low tundra shrubs, many of which are willow and alder species, have rapidly grown into small trees over the last 50 years, according to the study, led by scientists from the
Biodiversity Institute at the University of Oxford and the Arctic Center of the University of Lapland. The researchers foresee a substantial additional local warming influence from this change in landscapes, with the darker foliage absorbing sunlight that would otherwise be reflected back to space. But the fast-motion shift to forests will likely absorb carbon dioxide, as well.
. . .
“The speed and magnitude of the observed change is far greater than we expected,” said
Prof. Bruce Forbes of the Arctic Center, University of Lapland, corresponding author of the paper. Adds Dr. Marc Macias-Fauria from Oxford University, lead author, “Previously people had thought that the tundra would be colonized by trees from the boreal forest to the south as the Arctic climate warms, a process that could potentially take centuries. But what we’ve found is that the shrubs that are already there are transforming into trees in just a few decades.”
==============================