New research shows that tundra is turning to forests faster than expected due to climate change.
Researchers from Finland and Oxford University have found that small shrubs from the Arctic tundra mostly in Russia have grown into trees over the last several decades.
According to io9, the study looked at both satellite images and local observations and found that willow and alder shrubs had grown over six feet in the last 30 to 40 years.
The growth correponds with a period of rising temperatures in the region.
Read more on GlobalPost: Nearly One-tenth of mammals won't outrun climate change
"What we have found essentially is that the growth of these shrubs is really linked to temperatures," said study author Marc Macias-Fauria of Oxford University, reported Live Science.
"They are reacting to warming temperatures by growing more."
There are worries that as climate change creates "pop-up" forests, this new growth could speed up warming as the dark foliage absorbs sunlight unlike the white tundra which preceded it.
The advance of forest areas into Arctic tundras could increase warming in the region possibly one to two degrees by the end of the 21st century, reported Time.
The research was published in the journal Nature Climate Change.