[geo] Arctic sea ice - no multi-year ice found

[John Nissen]

It is now accepted by most scientists that the Arctic sea ice retreat is caused by anthropogenic global warming, though the exact mechanism for the "polar amplification" of global warming is not well understood.  Critical for sea ice survival is the multi-year ice. In his recent measurements of Arctic sea ice, Pen Hadow found absolutely no multi-year ice, and the one-year ice was about 4 foot thick.  This is extremely disturbing, because the one-year ice can melt away very suddenly, given warm weather.  So when Vick Pope says  that the sea ice could disappear "later this century", it is a gross understatement of the danger.  The Pen Hadow finding shows that the sea ice could disappear quite suddenly, if the natural variation in Arctic weather led to a much warmer than average summer, such as in 2007 only more so. http://vodpod.com/watch/1634449-british-team-finds-no-multi-year-ice The implications are: 1. The risk of massive methane outgassing is increased. 2.  The risk of Greenland ice sheet destabilisation is increased. 3.  Emissions reductions by end century will certainly be too late, even if they were to have a cooling effect in the Arctic. 4.  Geoengineering in the Arctic must now be deployed for cooling the Arctic. 5.  The sooner it is deployed the better, providing it is done carefully to reduce risk of adverse side-effects. 6.  Black carbon levels must also be reduced, as they help to melt snow and ice in the Arctic. Now I know that Vicky Pope considers that this is being apocalyptic.  But actually it's all about risk management.  The very argument she uses about variability actually increases the risk that the sea ice disappears much sooner than expected, as a violent swing on one side of the trend line.  This is what Vicky was writing in the Guardian in February this year: http://www.guardian.co.uk/environment/2009/feb/11/climate-change-misleading-claims [quote] Pope says there is little evidence to support claims that Arctic ice has reached a tipping point and could disappear within a decade or so, as some reports have suggested. Summer ice extent in the Arctic, formed by frozen sea water, has collapsed in recent years, with ice extent in September last year 34% lower than the average since satellite measurements began in 1979. "The record-breaking losses in the past couple of years could easily be due to natural fluctuations in the weather, with summer ice increasing again over the next few years," she says. [end quote] The result of this optimistic view of sea ice survival, promoted by the IPCC and continued by the Hadley centre, is that governments are blissfully unaware of the risk of sea ice disappearance and repercussions.  Furthermore, they are still being led to believe that emissions reduction alone can halt global warming before tipping points (such as sea ice disappearance) are reached.  This is absolute nonsense, since there is no way that emissions reduction can cause a cooling effect in the Arctic. In the same article, Vicky Pope said "the implications of climate change are profound and will be severe if greenhouse gas emissions are not cut drastically" - but if governments focus on emissions reduction alone, there is the danger of sea ice disappearance taking us all by surprise.  And then it will be too late. Cheers, John --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---