As the Arctic warms and previously barren land turns green, a team of Berkeley scientists has come up with a way to calculate the magnitude of change. Led by assistant environmental science, policy, and management professor Trevor Keenan, who has a joint appointment at the Lawrence Berkeley National Laboratory, the researchers have found that 16 percent of the land that used to be too cold for extensive plant growth is now warm enough for vegetation. By 2100, they estimate that only 20 percent of the northern hemisphere's vegetated land will be hampered by cold temperatures. "Although the greening might sound like good news as it means more carbon uptake and biomass production, it represents a major disruption to the delicate balance in cold ecosystems," Professor Keenan says. This story originated at Berkeley News.