The Role of Permafrost in the Global Carbon Cycle

Permafrost has an important role in the global carbon cycle over very long time scales. It's been a really long-term carbon sink that's been accumulating carbon as plant material for thousands of years. The temperature of the soil, which is primarily driven by the temperature of the overlying atmosphere, dictates how quickly it thaws. A lot of this ice is in the form of really pure ice wedges or ice lenses and can make up a really big part of the ground.