Re: [geo] SEA ICE LOSS STUNS SCIENTISTS - open letter to John Holdren

[John Nissen]

Dear all, I am pleased to say that a number of you, including Peter Wadhams and Gregory Benford, have endorsed the letter.  But some of you seem to have a problem with the tenor. I have tried to make the letter as forceful as possible, without implications that cannot be backed by science or logic.  We cannot expect rapid action unless the letter spells out the imminent danger very clearly.  The action we request is the setting up of a project, specifically to address the danger from the Arctic.  Because of the urgency, we need a well-resourced and focussed project, with determined leadership, hence the reference to "emergency action" and a project of "Manhattan intensity".  I hope that answers some concerns. However, Tom Wigley is concerned that one passage might be more guesswork than science: "... we can expect permafrost to release large quantities of methane, from as early as 2011 onwards, which will lead inexorably to runaway greenhouse warming and abrupt climate change." I would like to allay his concerns as follows. If all carbon trapped in permafrost were released as CO2, it would triple CO2 in the atmosphere [1].  A significant proportion will be released as methane, which a much more potent greenhouse gas than CO2.  Continued heating of the Arctic will inevitably lead to melting of permafrost.   This heating is accelating due to positive feedbacks.  A major feedback is from the albedo change when sea ice is replaced by water [2].  As the sea ice retreats, we can expect methane to be released in ever larger quantities.  The global warming effect of the methane will lead to further methane release, and further warming, in what can be described as thermal runaway.  Abrupt climate change could then be expected.  Massive methane discharge is thought to have caused abrupt climate change in the past, "on a timescale less than a human lifetime" [3]. So I think there is reasonable scientific grounds for what we have said. Regards, John [1] Copenhagen Diagnosis, p21 http://www.ccrc.unsw.edu.au/Copenhagen/Copenhagen_Diagnosis_LOW.pdf [2] Nature Letters http://sciences.blogs.liberation.fr/files/arctique-ann%C3%A9es-2000-tures.pdf [3] Clathrate gun hypothesis http://en.wikipedia.org/wiki/Clathrate_gun_hypothesis --- Tom Wigley wrote: John, You say ... "we can expect permafrost to release large quantities of methane, from as early as 2011 onwards, which will lead inexorably to runaway greenhouse warming and abrupt climate change." This is guesswork, not science. I do not want to sign this letter. Tom. +++++++++++++ John Nissen wrote: In view of the situation in the Arctic, I would be grateful for support for an open letter to John Holdren, along the following lines.  Please let me know whether you agree with this text and whether you'd be happy for me to add your name at the bottom. Cheers, John --- To John P Holdren, the Director of the Office of Science and Technology Policy Dear Dr Holdren, The Arctic sea ice acts as a giant mirror to reflect sunlight back into space and cool the Earth. The sea ice has been retreating far faster than the IPCC predicted only three years ago [1]. But, after the record retreat in September 2007, many scientists revised their predictions for the date of a seasonally ice free Arctic Ocean from beyond the end of century to beyond 2030. Only a few scientists predicted this event for the coming decade, and they were ridiculed. In 2008 and 2009 there was only a slight recovery in end-summer sea ice extent, and it appears that the minimum 2010 extent will be close to a new record [2].  However the evidence from PIOMAS is that there has been a very sharp decline in volume [3], which is very worrying. The Arctic warming is now accelerating, and we can expect permafrost to release large quantities of methane, from as early as 2011 onwards, which will lead inexorably to runaway greenhouse warming and abrupt climate change.  All this could become apparent if the sea ice retreats further than ever before this summer.  We could be approaching a point of no return unless emergency action is taken. We suggest that the current situation should be treated as a warning for us all. The world community must rethink its attitude to fighting global warming by cutting greenhouse gas emissions sharply. However, even if emissions could be cut to zero, the existing CO2 in the atmosphere would continue to warm the planet for many decades.  Geoengineering now appears the only means to cool the Arctic quickly enough.  A geoengineering project of the intensity of the Manhattan Project is urgently needed to guard against a global catastrophe. Yours sincerely, John Nissen [Other names to be added here.] [1] Stroeve et al, May 2007 http://www.smithpa.demon.co.uk/GRL%20Arctic%20Ice.pdf [2] http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png [3] http://nsidc.org/images/arcticseaicenews/20100608_Figure5.png --  You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineer...@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.