Re: [geo] Jim Hansen : 1 to 2DegC and 20m sea level rise

2011-07-22 Thread Ken Caldeira
I sure wish he would avoiding putting prescriptive statements in ostensibly scientific papers. Scientific papers should contain descriptive, not prescriptive, statements. That said, I think he is right about long-term climate sensitivity being higher than the century-scale sensitivity inferred

Re: [geo] Re: September sea-ice gone by end of century? (or much sooner)

2011-07-22 Thread John Nissen
Hi David, I disagree with your estimation of 12 years and suggest 5 years is more likely and could even be optimistic, at least for September sea ice decline to below the 10% mark. The PIOMAS graph, updated to end June 2011 here [1], made me think that 2016 was the most likely date, fitting a

Re: [geo] Re: September sea-ice gone by end of century? (or much sooner)

2011-07-22 Thread Andrew Revkin
Why don't those of you dipping a (cold) toe in this arena enter the Sea Ice Outlook comparison held each season by SEARCH? http://www.arcus.org/search/seaiceoutlook/guidelines (I noticed that WattsUpWithThat did~ ) More on that effort from Dot

Re: [geo] Jim Hansen : 1 to 2DegC and 20m sea level rise

2011-07-22 Thread John Nissen
Dear Ken, I've already looked at this interesting paper [1], from Jim Hansen and Mikiko Sato - but I'd not read before of his conjecture about rate of ice mass loss doubling per decade, producing many metres of sea level rise this century. But the implication is that the situation can be saved

Re: [geo] Jim Hansen : 1 to 2DegC and 20m sea level rise

2011-07-22 Thread Ken Caldeira
Two points: I am not opposed to scientists making prescriptive statements in their roles as citizens. However, I am opposed to prescriptive statements (statements about what we should do) in peer-reviewed scientific papers. I think science is about establishing objective facts about the

[geo] Arctic methane workshop, London, 15-16th October CONFIRMED

2011-07-22 Thread John Nissen
Dear all, In case you were not aware, the workshop, which was to have been 3-4th September, is now going to be on 15-16th October. Here is the background and purpose of the workshop. A group of scientists and engineers (including myself) is deeply concerned about the potential of methane from