A new study indicates that as the number of dark-coloured shrubs in the otherwise stark arctic tundra rises, the amount of solar energy absorbed could increase winter heating by up to 70 percent.
The research, conducted by the US Army Cold Regions Research and Colorado State University, presents the first evidence that shrub growth could alter the winter energy balance of the Arctic and sub-Arctic tundra in a substantial way.
Matthew Sturm, lead author of the study, said: “If tundra is converted to shrub land, more solar energy will be absorbed in the winter than before.”
While previous research has shown that warmer temperatures during the arctic summer enhance shrub growth, Sturm said: “Our study is important because it suggests that the winter processes could also contribute to and amplify the rate of the [growth].”
In addition, the increasing shrub cover would impact more than just the energy balance in the Arctic. The study concludes that the combined effects of increasing shrubs on both energy and carbon could change the Arctic in a way that affects the rest of the world.