Can Methane Hydrates Contribute Significantly to Present Global Warming?

This is a question I once posed to another blog but received no answers.

Whether you subscribe to global warming or not, I think there can be no denying that greenhouse gases are increasing. Climate scientists seem to think all or most of these gases are anthropogenic. I would like to pose another possibility and blame a little of the greenhouse gases on a burbing mother earth.

The formation of methane hydrates occurs in deep ocean environments. These ice like structures are usually trapped in the sediments of the oceans and don't get released unless disturbed. It is even thought that the hydrates can act like a thermostat and be released when ocean levels drop as in an ice age. The released methane then reverses the ice age.

I have located some sites of interest for potential ocean generated climate warming gases. The information presented by these connections are not long but seem credible.

http://www.realclimate.org/index.php/archives/2005/12/methane-hydrates-and-gloal-warming/

http://web.mit.edu/newsoffice/2009/methane-0902.html

http://geosci.uchicago.edu/~archer/reprints/archer.2005.clathrates.pdf

The above sites relate to the methane potential that the oceans could have on Earth's climate. This potential is locked up as methane clathrate or methane hydrate and are usually difficult to release. Many of the plumes are only recently discovered and are difficult to locate. You should also look up clathrate gun hypothesis.

However, there have been recent discoveries of plumes (pockmarked) of methane or carbon dioxide released from the ocean reservoirs of methane clathrates (Storrega Slide near Norway). It is not yet known if these releases are a result of global warming and its effect on the oceans or if they have been released to the atmosphere over a much longer period. Methane release from clathrate breakdown has been thought to be the cause of past earth warming. The methane trapped as clathrate will exhibit similar footprint of fossil carbon. There is no good handle on the amount of carbon released from these newly found plumes. Better information can be found in the above articles.

We are all aware that methane is a very transitory molecule once exposed to the atmosphere ( it is converted to CO2 and water vapour). I have read that the pre-industrial age methane has been estimated at 1.0 ppmv and that is is now about 1.7 ppmv. The actual methane discharged to the atmosphere can be much higher than accounted but now disguised as CO2. It would be interesting to know if the increase of CH4 from these ocean plumes can be quantified into actual carbon as CO2 once it has been converted. The small increase in methane detected in the atmosphere may be a very small component of carbon released and converted to CO2. It would thus appear that all fossil carbon is not anthropogenic. Brilliant minds may have already resolved the issue as I see it. Let me know if you are aware of any studies.

However if it is not resolved, how can the carbon budgets be accurate if we cannot account for all the sources of carbon but simply say that all or most of the the fossil carbon is from man made activity? It seems obvious to me that the potential discharge of greenhouse gases from the ocean is larger than accounted. Questions of the earth (through the ocean) as a potential source of global warming remain unresolved in my mind. Can we stop global warming "simply" by stopping man made discharge of global warming gases? I do not refute global warming and man is certainly a significant contributor of global warming gases. I do believe that eventually we will need engineered solutions in conjunction with reduction. I would seriously question if reduction alone can reverse the global warming today. Or even if reduction can be significant to have any effect.