Tundra covers almost 20 percent of the Earth’s surface, and globally it has been thawing at deeper levels for longer periods of time. In parts of Canada, methane gas released from the frozen soils has been dated to more than 2,000 years old. A number of studies suggest that ancient carbon is emerging from Arctic soils, lakes, and rivers at rates faster than previously believed.
The Arctic has long been called the “canary in the coal mine” when it comes to climate change because it is warming at twice the rate as the rest of the world. Currently, the Arctic is a carbon sink because it holds a lot of the world’s carbon in its frozen ground. However, if this trend continues and transitions the Arctic to a carbon source, releasing more carbon than it absorbs, researchers say it could start a cycle that leads to further increased global warming and have implications beyond Alaska.
Researchers say they have measured a northward migration of shrubs and trees over the past decades, indicating that Alaska’s North Slope is transitioning to a boreal, or taiga, forest characterized by warmer temperatures, more precipitation, a greater presence of trees, and the northward migration of animals like moose and deer – who would compete with the Tundra’s reindeer.