Thawing permafrost releases old greenhouse gas

Source: Science Daily

The thawing permafrost soils in the Arctic regions might contribute to the greenhouse effect in two respects: on the one hand rising temperatures lead to higher microbial methane production close to the surface. On the other hand thawing subsurface opens increasingly pathways for old, geologic methane.

https://www.sciencedaily.com/releases/2017/07/170719084810.htm