Arctic Methane Emergency Group? refers. Via GP I find this discussion on a “geoengineering” newsgroup (gosh how quaint – people still use newsgroups? Maybe retro is back). AJL finds my article “damming” but Ken C finds it “a little distasteful”. But both are worried, quite rightly, about credibility if the AMEG’s wilder claims (and people) aren’t challenged.
Ken C points to September Arctic sea ice predicted to disappear near 2oC global warming above present (JGR, doi:10.1029/2011JD016709) which is interesting, because that is very non-catastrophic and very non-nearterm: 2 oC puts it at ~2070 or something, depending on your scenario.
A recalibration of an ensemble of global climate models using observations over 28 years provides a scenario independent relationship and yields about 2oC change in annual mean global surface temperature above present as the most likely global temperature threshold for September sea ice to disappear, but with substantial associated uncertainty.
Which brings me on to Now, and Cryosphere Today has a nice interactive chart, which I’ve inlined above (see-also). This year – yellow – seems quite wobbly; from bumping along the bottom it is now well up in the middle of the pack. But that is midwinter; there is still all to play for in the year ahead.
Switching very briefly to methane (the AMEG people were a bit annoyed their nice discussion had got hijacked by sea ice), the pic here shows… nothing very exciting. And it is Barrow, not global, per special request of Eli. This provides some kind of constraint on the hugeosity of whatever methane release is occurring in the Arctic.
And so, in the end, back to the Dark Side, where Watts had some story about sea ice. I ignored the bit about the Skate – if you’re interested, Eli has the story on that, and the other half too. But the bit about IPCC ’90 using pre-1978 sea ice was more interesting. Its true, they did (though it was a surprise to me). Presumably because back in 1990 the SSMI/R record was rather short, and it wasn’t obviously silly to use other stuff (for the full story, and exactly what other stuff, read RMG who knows). Anyway, I guessed wrong: it wasn’t ESMR (couldn’t have been, as RMG points out, because there would have been gaps). But what is fun, if you’re a detatched spectator, is how the Watties once again jump onto the good old conspiracy theories of how things were pure then but the global conspiracy has subsequently conspired to wipe out any memory of
our giant reptilian overlords whatever. This is definitely a case where you don’t need fancy explanations for their errors. There is a constant stream of junk, no time to think or evaluate, and no need anyway – its all denialotainment, nothing real, and like the headline in the Daily Mail will be conveniently forgotten very soon.
Oh, and don’t mention Scafetta.
* Anthony Watts Misleading His Readers About Surface Temperature Record – it might be convenient to put this where I might find it again
* How reversible is sea ice loss? J. K. Ridley, J. A. Lowe, and H. T. Hewitt