What will happen to the carbon frozen in permafrost?
After they die, plants and animals decay. This process releases methane, carbon dioxide, and other greenhouse gases. These gases move through Earth's carbon cycle. The carbon cycle helps sustain life on Earth. The amount of these gases released has been steady for a very long time. Earth's climate is in tune with the way these processes have been occurring.
But freezing stops the plant and animal from decaying. Some areas of permafrost have been frozen for thousands of years, preserving the plant and animal material trapped in its soils. If this permafrost thaws quickly as a result of climate change, the stored-up plant and animal matter would decay quickly, too. Permafrost can contain a lot of plant and animal material, so it could release a large amount of carbon dioxide and methane into the atmosphere. Scientists think that the amount of carbon trapped in permafrost equals the amount of carbon already in the atmosphere. The additional gases could speed up the rate of global warming. Then even more permafrost could thaw, releasing even more gases.