Methane Bubbles - What They Can Tell Us About the Impacts of Global Temperature Changes

The arctic regions are expected to suffer the brunt of any temperature increases associated with global warming. A major change concomitant with warming is the release of carbon in the form of methane through the thawing of permafrost.

The thawing of permafrost (soil that is at or below the freezing point of water), threatens to release carbon into the atmosphere in the form of vast amounts of methane, a greenhouse gas some 23 times more potent in terms of warming than CO2.
The primary natural source of methane (CH4) is microbial decay of organic matter under oxygen-free conditions in wetlands. As permafrost melts, it forms lakes which account for the majority of permafrost-derived methane emitted to the atmosphere via ebullition (bubbling). Previous studies appear to have grossly under-estimated the true rate of methane emission because random-sampling techniques can miss the ebullition sources, which occur in hotspots with little background emission.

Permafrost degradation has already been linked to changes in vegetation composition, ecosystem functioning and the damaging impacts of permafrost degradation-induced subsidence on civil infrastructure.