After getting thoroughly shouted at, I realised I needed to improve my 'runaway' arguments.
My current skeleton is below. However, it's currently missing a few crucial bones which now need replacing. I need citations for the following: 1) A clathrate gun effect that shows rapid release? Buffett and Archer, and Archer alone, show a slow release, although from a large reservoir. 2) A calculation of the eventual warming that may result from methane release from permafrost/clathrates. 3) A study showing the impacts of such a level of warming on human civilisation/survival. 4) What happens to methane sinks under conditions of bulk outgassing? Do they fail and massively increase the global warming potential of methane? We've discussed all these issues before, but I think it's now time to get any available research on the issue into the open. Is there REALLY a big and immediate risk from the clathrate gun/permafrost? A http://en.wikipedia.org/wiki/Effects_of_global_warming#Abrupt_climate_change The scientific consensus in the [[IPCC Fourth Assessment Report]] is that "Anthropogenic warming could lead to some effects that are abrupt or irreversible, depending upon the rate and magnitude of the climate change." The phenomenon of [[Arctic shrinkage]] is leading some scientists to fear that a runaway climate change event may be imminent<ref>http://www.guardian.co.uk/environment/2006/oct/18/bookextracts.books</ref>, and may even have started<ref>http://www.terranature.org/environmentalCrisis.htm</ref>. There is an [[albedo]] effect, as white ice is replaced by dark ocean. Rapid [[Arctic shrinkage]] is occurring, with 2007 being the lowest ever recorded area and 2008 being possibly the lowest ever recorded volume.<ref>http://nsidc.org/news/press/20081002_seaice_pressrelease.html</ref> This will induce or accelerate other [[positive feedback]] mechanisms, such as [[Arctic methane release]] from melting [[permafrost]] and [[clathrates]]. Lawrence et al(2008) suggests that a rapid melting of the sea ice may up a feedback loop that rapidly melts arctic permafrost.<ref>http://www.ucar.edu/news/releases/2008/permafrost.jsp</ref><ref>{{Citation | year=2008 | title=Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss | first=David M. | last=Lawrence | first2=Andrew G. | last2=Slater | first3=Robert A. | last3=Tomas | first4=Marika M. | last4=Holland | first5=Clara | last5=Deser | journal=[[Geophysical Research Letters]] | volume=35 | issue=11 | doi=10.1029/2008GL033985 | url=http://www.cgd.ucar.edu/ccr/dlawren/publications/lawrence.grl.submit.2008.pdf}}</ref> Estimates of the size of the total carbon reservoir in Arctic [[permafrost]] and [[clathrates]] vary widely. It is suggested that at least 900 gigatonnes of carbon in permafrost exists worldwide.<ref>http://www.terranature.org/methaneSiberia.htm</ref>{{fact}}. Further, there are believed to be around and another 400 gigatonnes of carbon in methane clathrates in permafrost regions alone.<ref>http://www.springerlink.com/content/r4w867922g607w2j/</ref>. Should this estimate of volume be correct or at least too low, and if clathrates are omitted from the analysis completely, then 900 gigatonnes of carbon may potentially be released as methane as a result of human activity. [[Methane]] is a potent [[greenhouse gas]] with a higher [[global warming potential]] than [[CO2]]. A release on this scale will create [[catastrophic climate change]]. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
