Excerpts from Books and Wikipedia
"The Siberian frozen bog is estimated to contain 70 billion tons of methane. If the bogs become drier as they warm, the methane (CH4) will oxidize and the emissions will be primarily carbon dioxide (CO2). However, if the bogs stay wet, as many have in recent years, the methane will escape directly into the atmosphere. . . . A December 2011 article in Nature, 'Climate Change: High Risk of Permafrost Thaw,' surveyed 41 international experts, called the Permafrost Carbon Network, who publish on permafrost issues. They concluded, 'Our collective estimate is that carbon will be released more quickly than models suggest, and at levels that are cause for serious concern.' They project as much as 380 billion metric tons of carbon dioxide equivalent will be released by 2100. They calculate that the defrosting permafrost will release roughly the same amount of carbon as current rates of deforestation would release. However, 'because these emissions include significant quantities of methane, the overall effect on climate could be 2.5 times larger.'” [Romm, p. 84, 87]