There is a lot to learn about the effect of another 1 ppm of CH4 in the atmosphere, are we are going to learn it the hard way.
Methane and Frozen Ground National Snow and Ice Data Center
What are the sources of methane in the Arctic?
There are two potential sources of methane in the Arctic. The first source of methane is called methyl clathrate. Methyl clathrates are molecules of methane that are frozen into ice crystals. They can form deep in the Earth or underwater, but it takes very special conditions, with high pressure and low temperature, to make them. If the temperature or pressure changes, the ice that imprisons the methane will break apart, and the methane will escape. We're not sure how much methane is trapped in methyl clathrates, or how much is in danger of escaping.
The other major source of methane in the Arctic is the organic matter frozen in permafrost. This is the source of methane that I study. The organic matter in permafrost contains a lot of carbon. It is made of dead plants and animals that have been frozen deep in permafrost for thousands of years. As long as this organic matter remains frozen, it will stay in the permafrost. However, if it thaws, it will decay, releasing carbon dioxide or methane into the atmosphere. This is why permafrost carbon is important to climate study.