In total permafrost covers about 23 million km2, more than double the size of the US, and as such it’s not something that can be tackled on a local scale, it needs a global solution.
Numerous scientific studies have been conducted and between them they estimate that the total carbon content of methane trapped beneath the permafrost is about 1.5 gigatonnes, but as you mentioned, the global warming potential of methane is significantly higher than that of carbon dioxide.
If 15% of the permafrost were to melt then it would enhance the greenhouse effect by the same amount that all our emissions of carbon dioxide have done. Prior to the onset of industrialisation the amount of CO2 in the atmosphere was 280 parts per million by volume, today it is almost 400ppmv. The melting of 15% of the permafrost would be the same as adding a further 120ppmv of carbon.
Permafrost is melting and in the last few years alone a million km2 in Siberia has turned to mud, peat and lakes. It gives off enough methane gas to be able to ignite it with a match.
On the plus side, methane doesn’t reside in the atmosphere for as long as carbon dioxide does, an average of 12 years per molecule as opposed to an average of 115 years. If the release of methane is slow and over a long period of time then the effect on the climate would be relatively small. For example, if all permafrost were to melt over a period of 230 years at a steady rate of 100,000km2 per year then after 12 years there would be as much CH4 entering the atmosphere as there was leaving it, thus an equilibrium would be reached. This would occur at a point that would cause about 0.35°C of additional warming.
The worry is that the permafrost could melt significantly quicker. Until fairly recently a lot of the research tended to underestimate the effects of CH4 release but we now know that it’s melting faster than had been predicted and contains more CH4 than originally thought (the above figures use the revised data).
We’re not screwed. Even if all the methane were to be released in one go, such a thing can’t happen but if it did, the planet would rapidly warm by about 7°C. This would have a massive impact on everyone and we’d have to make some very major adjustments to our lives, but we’d survive (most of us).
The more likely reality is that permafrost will continue melting as it has been doing in recent years and steadily releasing methane into the atmosphere. This will enhance global warming but not to a catastrophic level. Indeed, for many the additional warming will be beneficial, others would need to make some adaptations but nothing too dramatic.
http://www.lter.uaf.edu/dev2009/pdf/1350...
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EDIT: TO JIM
The difference is that when I state an average figure of 115 years as the atmospheric residence period of CO2, I can back it up. The IPCC for example gives an average of 102.5 years [1], the Carbon Dioxide Information and Analysis Center states it’s approx 100 years [2], the study “Greenhouse Gases and Aerosols” provides an average of 125 years [3]. If I’d have wanted to be alarmist about it I would have stated that the ARP is thousands of years with the effects lasting millions of years [4]. Now let’s see you provide links that show CO2 has an ARP of 20 years.
[1] http://www.ipcc.ch/ipccreports/tar/wg1/0...
[2] http://cdiac.ornl.gov/pns/current_ghg.ht...
[3] http://rivernet.ncsu.edu/courselocker/Pa...
[4] http://melts.uchicago.edu/~archer/reprin...
Read this article from Nature, it explains that there is little to worry about as it will take thousands of years for the methane to be released.
http://wattsupwiththat.com/2013/07/16/na...
the earth used to be tropical all over. your worried that the earth will turn into an all ocean inferno. the truth is that you may celebrate new years eve on the beach, visit an russian museum of coats and having any season a swimsuit season. water doesn't expand it evaporates.
Trevor suggests he is a climate scientist and then suggests that CO2 has a resident time of 115 years. Either he is a very careless scientist that refuses to say when something is a fact or a theory or he is a English major who plays climate scientist on the internet. I could say CO2 has a resident time of 20 years and methane is more like 5. My estimate is just as valid as his. The only problem is that his alarmism falls apart if my estimate is more accurate.
Recent scientific studies with empirical data sets, NOT models and dreams, demonstrated that these fears are false. Permafrost areas were defrosted under a controlled environment and off gasses were measured and recorded. The Release of methane was NOT meaningful and nowhere near the magnatude your links suggeest. Take those estmates and drop them by several orders of magnitude and you will start to come close to measured values.
So to answer your quesiton. Nothing is being done. Nothing needs to be done and no we are not screwed.
I keep hearing all this stuff about how methane is a greenhouse gas 22 times stronger than CO2 and that if the permafrost melts then gigatons of methane will be released and kill everything on the planet.
OK.
What exactly is being done to keep the permafrost in place?
Sources:
http://www.livescience.com/37359-nasa-carve-thawing-permafrost-gas.html
http://en.wikipedia.org/wiki/Arctic_methane_release
http://thinkprogress.org/climate/2011/12/01/379675/nature-climate-experts-thawing-permafrost-warming-of-deforestation/
