The UK's Met Office is not alone in their predictions, as at least one metastudy I've seen suggests similar dates. However, we should bear in mind that the track record on AGW is usually that things are worse than expected.
I think that 2060 is pretty soon. I'll still be alive. Furthermore, we'll have had many years of dark oceans and melted permafrost by then - all helping to push us further down the downward spiral of feedback. I've yet to see convincing modelling of these feedback effects - largely because no-one seems to be sure how much carbon's in the permafrost. I'm still keen to see modelling that shows convincingly that we can use geoengineering to restore the ice once it's gone. A 2009/10/28 David Schnare <[email protected]> > For those of you who think the Arctic ice will be gone soon, perhaps you'd > like to see what the UK Met Office thinks. 2060! > > This is from Anthony Watt's website. > > UK Met Office backpedals on Arctic Ice – “…unlikely that the Arctic will > experience ice-free summers by > 2020.”<http://wattsupwiththat.com/2009/10/28/uk-met-office-backpedals-on-arctic-ice-unlikely-that-the-arctic-will-experience-ice-free-summers-by-2020/> > 28 10 2009 > > But they do say that “first ice-free summer expected to occur between 2060 > and 2080″. By then there will be nobody that remembers this forecast. > > Yet on the same day, bumbling Arctic explorer Pen Hadow says in a *UK > Telegraph > interview*<http://www.telegraph.co.uk/earth/earthnews/6326446/Arctic-will-be-ice-free-in-a-decade-according-to-Pen-Hadow.html> > : > > “*To all intents and purposes the Arctic will be ice free in a decade. I > do find the implications of this happening in my lifetime quite shocking.* > “. > > Gosh, who to believe? Somebody that fakes biotelemetry > data<http://wattsupwiththat.com/2009/04/08/catlin-ice-survey-website-recycles-biotelemetry-data/>or > somebody that won’t > hand over climate data for replication > studies<http://www.climateaudit.org/?p=6654> > ? > > From a Met Office *press > release*<http://www.metoffice.gov.uk/corporate/pressoffice/2009/pr20091015b.html>on > October 15th > > [image: Arctic sea-ice] > > The extent of Arctic sea ice has been decreasing since the late 1970s. In > 2007 it decreased dramatically in a single year, reaching an all-time low. > At the time it was widely reported that this was caused by man-made climate > change and that the rate of decline of summer sea ice was increasing. > > Modelling of Arctic sea ice by the Met Office Hadley Centre climate model > shows that ice invariably recovers from extreme events, and that the > long-term trend of reduction is robust — with the first ice-free summer > expected to occur between 2060 and 2080. It is unlikely that the Arctic will > experience ice-free summers by 2020. > > Analysis of the 2007 summer sea-ice minimum has subsequently shown that > this was due, in part, to unusual weather patterns. Arctic weather systems > are highly variable year-on-year and the prevailing winds can enhance, or > oppose, the southward flow of ice into the Atlantic. Consequently, the sea > ice has not declined every year, but has shown considerable variability — > both in extent and thickness. > > The high variability has made it difficult to attribute the observed trend > to man-made emissions of greenhouse gases, although there is now enough data > to detect a human signal in the 30-year trend. The trend and observed > variability, including the minimum extent observed in 2007, is consistent > with climate modelling from the Met Office. > > About half of the climate models involved in the Intergovernmental Panel on > Climate Change fourth assessment report, show that ice declines in steps — > failing to recover from extreme years. The observed temporary recovery from > the 2007 minimum in 2008 and 2009 indicates that the Arctic ice has not yet > reached a tipping point, if such exists. We expect Arctic ice to continue to > decline in line with increasing global temperatures. If the rate of global > temperature rise increases then so will the rate of Arctic sea-ice decline. > > -- > David W. Schnare > Center for Environmental Stewardship > > > > --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
