Carbon dioxide was predicted to be most of the gas released from thawing carbon-rich frozen soil of the Artic by scientists. However, new research has shown that Methane levels may be considerably higher as arctic permafrost thaws.
Methane does not last in the air for more than a decade but its warming effect is many times that of carbon dioxide over a 100 year period. Recent studies have shown wet soil/wetlands emits more methane than dry areas.
This could affect overall permafrost influenced global warming.