A release of greenhouse gas emissions is part of what many refer to as a feedback loop; wherein increased levels of carbon dioxide cause global warming which causes the thaw of permafrost which releases carbon dioxide which takes us back to the beginning and enhances the global warming.

 
Siberian Caves Point To Devastating Future Thawing And CO2 Release (via Planetsave)

A team of scientists from Britain, Russia, Mongolia, and Switzerland have released a report which finds that evidence obtained from Siberian caves suggest that a global temperature rise of 1.5 degrees Celsius could result in permanently frozen ground end up thawing across a massive swathe of Siberia…