cut and past from:
https://www.wunderground.com/resourc...st.asp#warming
Permafrost stores an immense amount of carbon and methane (twice as much carbon as contained in the atmosphere). In a warming environment, permafrost is expected to degrade, and these gases which have been in storage will be released. This process has already begun in some parts of the world, including western Siberia, and is expected to increase in earnest by the year 2020. Furthermore, as of 2011, no climate model incorporates the effects of methane released from melting permafrost, suggesting that even the most extreme climate scenarios in the models might not be extreme enough.
Carbon
A third of the Earth's soil carbon is found in the Arctic tundra soil, stored in frozen organic matter. If the high northern latitudes warm significantly (as they are expected to; see Figure 3), permafrost will thaw, allowing the organic matter within the permafrost to decompose. The decomposition will release carbon into the atmosphere. This already happens within the active layer each summer. As the active layer thaws, some organic matter decomposes. Under normal climate conditions (i.e. a cold arctic region), the ground remains cold enough to keep the decomposition very slow. But as air temperature increases and the ground warms, this process will speed up, and scientists think this could begin very soon. Some suggest the arctic tundra could go from being a carbon sink to a carbon source by the mid-2020s.
Researchers at the National Snow and Ice Data Center estimate that by 2200, 60% of the Northern Hemisphere's permafrost will probably be melted, which could release around 190 billion tons of carbon into the atmosphere. This amount is about half of all the carbon released in the industrial age. The affect this will have on the rate of atmospheric warming could be irreversible. At the very least, these estimates mean fossil fuel emissions will have to be reduced more than currently suggested to account for the amount of carbon expected to discharge from melting permafrost.
Peatlands are also expected to be impacted by global climate change. Peat is made up of dead organic material, and so is very rich in carbon. It consists of 90% water and 10% plant matter, and is mostly found at the high latitudes of the northern hemisphere, both at the surface and below. Some of this peat is found underneath the permafrost layer, which means the carbon it harbors could be in jeopardy should the permafrost melt. In a study of the world's peatlands, one recent study found that if the globe warms 1°C over the next few decades, this could lead to a release of 38-100 million tons of carbon per year from peat alone.
Methane
Figure 3. Methane bubbles. Image credit: Walter et al., 2006.
In moist areas, most of the emissions will be of methane, a greenhouse gas that has 20 to 25 times more warming power than carbon dioxide. As the ground warms, methane will either be released directly into the atmosphere or bacteria will break it down into carbon dioxide, which will then be released. If areas of thawed permafrost exist at depth between frozen layers, it's possible that microbial activities will continue unabated, even during the winter, to create new methane from organic material.
This is what is believed to be happening around Siberia's lakes. In 2006, researchers working at two northern Siberian lakes found that methane was bubbling up from thawing permafrost at a rate five times faster than originally thought. The study also found an expansion of "thaw lakes" in the permafrost regions. Studies conducted in Canadian and Swedish permafrost and peatland regions also show these trends.
Methane hydrates can be thought of as methane gas frozen into ice structures, like the one in Figure 5. They're formed at cold temperatures and under high pressure—conditions that are both present beneath layers of frozen permafrost. The amount of methane hydrates in permafrost could range anywhere from 7.5 to 400 billion tons of carbon-equivalent.
Methane hydrates are abundantly present in and near the Siberian Ice Complex, or Arctic Shelf, which provides a shelf-like structure to support the land and coastline on top of it. As waters along the northern coast warm, the ice complex melts, allowing for quick erosion compared to the historical rate. In these areas, the water contains 2500% of the methane found in average atmospheric conditions. And recent research shows the amount of methane currently being released from the Arctic Shelf region is around the same amount of methane being released from all the oceans in the world. This is particularly dangerous because of the Shelf's shallow depth. In other regions where methane hydrates exist, they are deep enough to oxidize to carbon dioxide before reaching the surface. In this region, the methane is released directly into the air.
The Global Monitoring Division of NOAA's Earth System Research Laboratory allows you to plot time series of various atmospheric gases, including CO2 and CH4.