Large amounts of methane are leaking into the atmosphere from a section of seafloor under the East Siberian Arctic Shelf, according to new study by an international research team. Methane is a greenhouse gas that lies frozen in sediments and permafrost -- frozen soil that remains below 0°C for several years -- in arctic continental shelves.
Permafrost was thought to act as a leak-proof barrier that sealed in the methane, but warming arctic temperatures are thawing the permafrost.
And the frozen methane is not only dissolving in the water -- it's escaping into the atmosphere. The researchers say that release of just a fraction of the methane stored in the shelf could trigger sudden climate warming.