Methane, Permafrost and Climate Change

Additional Resources Climate Change

While Carbon dioxide (CO₂) emissions tend to receive the most attention with respect to their contributions to a changing climate, another greenhouse gas (GHG), methane (CH₄), more powerful but less long lived that CO₂, continues to receive attention.

More specifically, methane emissions from land and sea based permafrost regions of the the circumpolar North are receiving more attention because the area has, to date, experienced the most significant warming episodes.

Research by Martin Kennedy, a geology professor at UC Riverside, gets credit for framing today's permafrost methane emissions discussions.

The research concludes "An abrupt release of methane, a powerful greenhouse gas, about 635 million years ago from ice sheets that then extended to Earth's low latitudes caused a dramatic shift in climate, triggering a series of events that resulted in global warming and effectively ended the last "snowball" ice age".

Could a similar scenario happen again? No one knows for sure. One of the most recent articles in EOS, a journal of the American Geophysical Union, says four methane emissions research questions remain unanswered.

1. What is the size of the permafrost carbon pool?
2. Which fraction of this pool will be converted to methane upon thaw?
3. Which fraction of the permafrost carbon pool will thaw under anaerobic versus aerobic conditions?
4. What is the role of methane oxidation in controlling methane emissions?

What is the status of current research on these questions? Here are a couple of examples.

Potential feedback of thawing permafrost to the global climate system through methane emission. It's a 2007 research article that models climate change due to changes in Russian permafrost. Average global temperature rise predicted=0.012^oC. The research does not address sea bed methane emissions.

Shakhova, Semiletov and Panteleev report on early (2005) research examining current and potential Arctic seabed methane emissions from the East-Siberian Sea. They conclude, "Following some authors this range almost reaches the lowest estimate of whole World Ocean methane contribution and exceeds up to four times the annual flux estimated for all coastal seas"

Large-Scale Controls of Methanogenesis Inferred from Methane and Gravity Spaceborne Data. The most recent (January 2010) research estimates that current permafrost methane emissions constitute 2% of total global methane emissions.

With the exception of noting increasing temperatures in permafrost areas and concluding a need for additional research in the area of permafrost methane emissions, that's about all you can report on the topic without fear that the oil company funded climate police will attempt to arrest you or cut off your funding.

© 2010. Patricia A. Michaels