Are the F-17 sensor issues behind the bizarro numbers Cryosphere Today have been posting recently? Areal variations of 700,000 sq km per day can't possibly be right. (obviously there are some data quality assurance issues as well, but that's another story...)

3.9 million sq km. Extent is a horrible metric and one which I pay little attention to, so this is with low confidence. I forecast a dead-cat bounce six weeks ago on the Forum, and I see little reason to change yet. Those who have projected low end numbers based on expected volume drops are not considering a key aspect of extent, IMO. Since since a healthy tight pack with good volume and a broken diffuse pack with low volume can produce the same extent, falling volume does not necessarily correlate well with falling extent. This year's pack seems thin but (until recently) well spread. That perhaps makes it vulnerable to massive reductions in area, but I believe extent is likely to hold up somewhat better. As to Fufufunknknk's scale, I'd give myself about 10 years as a 1.3. That is, 5 years as a 1, 3 years as a 2, 2 years as a 1. The three years as a 2 was fun, but took up too much "real life" time to sustain.

Mine were nearly all neutral too. Now, I know this might seem like a whole lot of "conspiracy ideation", but I suspect Cook and his peeps are not really trying to quantify the consensus on climate change via crowdsourcing. Other authors have done these studies and Cook says that they've already done the work: "we analysed over 12,000 papers..." My money is on data mining for the next round of papers with Lewandowsky et al, perhaps a parthian shot before Lew heads off to his new chair in Bristol. A strongly bimodal result on a subset of papers will make some nice grist to the psychological mill. Did I just reveal to the Milgram "teachers" that they were actually the subjects of the experiment? If so, my bad. I trust the select readership here to do this survey faithfully. I have less confidence in the residents of other highly-trafficked blogs. I can't imagine why Cook et al would feel otherwise...

Thanks for the hat-tip, Neven. I must say, I laugh to look at my original efforts to find a bit more "texture" in PIOMAS results when I see the truly incredible work done by Wipneus and Chris (and quite a few others) since then. PSC's helpfulness has greatly enhanced the quality of the analysis posted here and thus the standing of this blog. And I like to think this blog has helped advertise the quality of their work to the wider world. So five cheers all round!

Jim, that's your best one yet! I always liked the polar plot, but thought it had a bit much detail to be really punchy - this is a classic case of less is more. I like the animation you've done, too - again simple but effective.

Wipneus - I take the years to be inclusive, so 2010 - 2012 is three autumns (not two). Hence my 6.5 rather than 5.5 as a straight subtraction would give. But either way, its a lot more than suggested at the head of the article. Anyway, my ranting aside, its good to see another source validating the quality of PSCs model. Many here have invested a lot of energy in interpretation and visualisations of that output (with excellent results). Boosting confidence in the fundamental quality of the reference data in always nice.

"Arctic sea ice volume has declined by 36 per cent in the autumn and 9 per cent in the winter between 2003 and 2012, a UK-led team of scientists has discovered." That's a shocking bad hat on that story. Para 1 states a 36%/9% reduction between 2003 and 2012 (10 years). That is so bogus, and completely at odds with the rest of the article. The fact that it comes straight from the NERC makes me facepalm. How many will read the first para only, and miss what follows? Its a 36% reduction between the 2003-08 average and the 2010-12 average. Since ice volume was declining through 2003-08 and 2010-12, 2003 was surely above the average for the first period while 2012 was probably below the average for the second period. So if you are talking a 10 year decline, it is certainly more than 36% for autumn, and probably more than 9% for winter. Put another way - inaccurately, but probably closer than para 1 of the press release: If we assume the decline was linear in these two periods (not the same slope on both), average would occur at the midpoints of the two periods: 2005.5 to 2011 - 6.5 years, not the ten years implied. A linear extrapolation to cover the stated 10 year period of 2003 to 2012 would suggest an autumn loss in the range of 50% - 55%. Sheesh! rant mode off...

I've worked for four governments (different levels / different countries) over 25 years and I've never seen anything that resembles their description of theirs of reference: "...Parliament asked the government ‘to also involve climate skeptics in future studies on climate change’...As a result of this, the Ministry of Infrastructure and the Environment announced a couple of projects [including Climate Dialogue]." Could any of our Dutch residents comment further about the background here? I assume the Minister instructed the Ministry to act, but what was her impetus - embarrassing questions in Parliament (from who?), a recommendation from a committee (composed of...?), a motion passed in the house(following a debate?) I'm highly skeptical of the motivations at play here, and am curious about exactly how the parliament "asked" the government to include skeptical views.

Could it be in the bag? I'd say so, Neven. The Antarctic area curve is assymetric, with the major part of the melt occuring in a very short space of time, while growth through Autumn and Winter is slower. Antarctica is now hitting the steepest part of the curve, with daily (negative) changes averaging perhaps as much as 40 K per day more than the Arctic's positive change. While that 20.641 might still get beaten for the annual max (I don't think it will), I'd say 2012 beating the previous low of 20.902 is locked in.

Kara anomaly now at a record -0.5 M. The only larger anomaly reported was an uncorrected sensor glitch in 2006. Other areas on the Atlantic side have not yet built up large -ve anomalies, but Barents, Hudson Bay and Baffin (in that order) are beginning to do so.

idunno, My first response is probably no (always subject to input from the better-informed). Sandy has (and will) mixed water between Cape Hatteras and Newfoundland. As far as I know there are no substantial methane clathrate deposits along those coasts. Sandy was certainly pumped by the high SSTs off the NE US coast, and those high SSTs are consistent with / linked to (etc) high SSTs in the whole Gulf Stream that have persisted for some time, as seen in the anomalous conditions we have been seeing this year in the Barents Sea (and the Kara, to a lesser extent). But the mixing you are talking about is "local", and would need to occur reasonably near a large deposit to have a marked effect. That might occur if it remains an intense storm over the North Atlantic and runs into Norway, which has some deposits along its coast. Otherwise, yes Sandy has caused warmer water to be mixed deep, but by the time that water is carried on the Gulf Stream far enough to impact on some deposits, it would have dissipated a lot of that heat, and I doubt deep water temperature would be notably different where it matters, so I can't really see it being an issue. If the wacc'y jetstream + cold front setup that drew it westwards on to land had not occurred, it would have hooked out to sea (the more normal path for these hurricanes). In that case it would be more likely to have had such an effect on Norwegian deposits. Just a guess.

Thanks, Wipneus. That suggests 2013 shapes an an interesting test on the whole exponential -v- sigmoid debate, or (with tongue in cheek) catastrophists -v- gradualists, to invoke some old-school terminology... This year reality went a little below Larry's Gompertz and a little above your exponential; but since both predictions were fairly close to each other (given daily -v- monthly), the result shed little light on the question. But next year sees quite a divergence in the predictions - again, even allowing for your different baselines, and the substantial error margins, Larry's 3.1 is quite a distance from your 1.9. A 2009-type result would flirt with the upper limit for exponential, while a 2010-type would be on the lower bound for Gompertz. Neither result would totally rule the less successful model out entirely of course. More likely, reality will track close enough to both to be within the error bars of both and once again we be left debating. But there is a moderate chance that one will emerge as the somewhat better bet.

Somewhat more on topic... If Wipneus is following this thread, I'd be very interested to see if he's done an early-bird "just-a-bit-of-fun, don't-take-it-too-seriously" forecast for September 2013? IMO, this years volume tracked his projections, however "naive", like they were on a rail, and following that success, I'm looking forward to his projection for next year.

Lewis, if you put an audacious idea out there and don't want people to disagree, its probably best not to end your post with: If you or others have thoughts on aspects of the above - I'd be glad to hear them. It conveys the idea that you are interested in boos as well as the cheers. My own take? At this point, geoengineering is like grabbing another bucket to bail the sinking boat. If little effort is going into stopping the damn leak, perhaps that's doing little more than delaying the inevitable. If it can keep us afloat long enough to plug the leak then yay! But my cynicism says that bailing harder while doing little to stop the leak is just an invitation to the fat bastard in the stern who is doing little but weigh the boat down more to say "Meh, the water's not coming in so fast..." As for whether it matters what we say...so, what, the guy from EPA goes to President Schwarzenegger and lays out five geoengineering plans and the President says: "No! I read on Neffen's blog dat ve are all dooomt anyvay..." ? :-)

Rob, perhaps I misunderstood you, but the Antarctic Ice isn't "rotten" - its first year ice, so it's too young for that. The pack around Antartica is loose at the margins. I haven't been watching it avidly, but it seems to have been compacted on the margin facing the eastern Pacific over the last few days (at least, at present, it is high-concentration ice almost to the pack edge). Would read too much into it, myself.

Of course, "...bet a shiny penny..." *facepalm*

Peter - just so. Unless they cool remarkably quickly, the Kara, Laptev and East Siberian will be late freezing over and will push downwards from their current anomalies. My (fairly conservative, I think) estimate of the change in the anomalies over the next three weeks is around -300K, -200K and -200K, contributing a handy -700K to the current anomaly of -2.5 million. I would be a shiny penny on the anomaly reaching -3 million, even while absolute area doubles from the current 2.7 million.

Just to expand Kris' point slightly, as the dry air descends from the mountain / plateau it also increases in pressure and warms, thus making the relative humidity even lower. In this specific geographic condition, the katabatic or foehn (similar but different) winds are remarkably dessicating. This condition does not apply to the Arctic Ocean of course, except perhaps a few points around Greenland.

sorry, busted tag. Should read: ...but Navy's loss is NOAA's gain. Either way, the US armed forces have lost a great advocate for reality-based policy-making.

The brief audio of RADM David Titley @ ~3:20 reminds me to note that he retired from the Navy a few months back (we probably all knew that already, but I hadn't seen it remarked on here). I have no idea whether his public comments on the state of the Arctic and its likely future played a part in his exit (he had been eased away from climate change activities last year), but Navy's loss is

Chris, re goalpost shifting - Yes I thought the same as I typed that out. I first pegged 1 M sq km back in the days when 3-point area was a relative novelty, and have really reset. This year has challenged everyone to reset their perspectiv-o-meters, doom'n'gloomist and she'llberightist alike. Your proposed 0.25 (might be a bit low for my tastes) is probably still above the tail I was thinking of; I don't have a figure for glacial contributions, but I expect its in the 10,000 to 100,000 range. The problem with 250,000 sq km is that is getting quite close to the "noise" of weather driven fluctuations which reach 150-200 k most years.

Dabize, Chris, Wipneus - i agree with your points. It is certainly easy to distinguish glacial ice from sea ice if you get up close. And for big chunks freeboard differences would show up on a satellite swath passing over a particular chunk. And I completely agree that the area involved is trivially small - since I personally consider "ice free" to be best represented by <1 million sq km, it is below my own threshold. My point is very much about the numbers actually presented here, not the reality of the processes. THe fact is, we currently include fresh water icebergs in the "sea ice area". Even if careful thikness measurements were used to exclude the bigger chunks, a single calving produces a lot of smaller pieces that cannot be distinguished from sea ice without physically inspecting them*. They are part of the numerical picture now, and even if we reach a point where no sea ice forms even in winter, we will still have little bergy bits calving of glaciers and sloshing around. I'm sure someone in 2070 will say, "Look, ice area is 625 sq km's! And those alarmists said we'd be ice free by xxxx." As to the more substantial point of whether actual sea ice will crash to zero or find some little refuge areas and form a genuine (if thin) tail, I remain agnostic. I've heard enough good arguments on both sides to know that I dont know enough. But I'm sure that we will not have to wait long to find out. Chris - your recent post on this theme was one of your best, for mine. * I suppose at some point in the future, it will be possible to physically inspect every piece of ice in the Arctic Ocean, by sailing up to it. ;-)

With regard to exponential / quadratic / Gompertz discussions, it must be a sigmoid (s-shaped curve, of which a Gompertz is just one type). Here's why: Arguing for accelerating decline until flatlining at zero (as I did in the past) misses the point that sea ice measurements do not only include sea ice in the literal sense (that is, frozen sea water). Land ice calving off glaciers is also included once it sets sail from its parent glacier. So as long as Greenland is generating ice islands, there will always be some (trivially small) amount of ice being topped up and picked up on sensors. Even if the Arctic Ocean was a uniform 10 degrees celsius, there would be some floating ice to measure (although any given 'berg would not last long in such conditions...) The inevitable conclusion is that even if one allows no negative feedbacks on sea ice (which would normally mean a crash to zero), there must be some (probably extremely small) area for decades to centuries afterwards. It won't be actual sea-ice, but it isn't now and it currently counts to the total, and would go on doing so. A Gompertz is the best curve, however the recurve will probably be a sharp corner, and the tail long and thin... 2 cents worth.

The green is not an algal bloom, it is, as Neven surmised an imaging artifact due to the low angle of the sun (cf: why is the sky red at sunset?) The same artifact is seen on Antarctic mosaic. And since thats on land, (in best Alec Guinness voice) "that's no bloom." Of course, on the Antarctic mosaic, because its on white snow, it looks yellow; on mixed white-and-blue fragmented ice in the Arctic, it looks green.

"The fact that we do not need to debate and create even more diatribe in what is an already over stuffed area may be an indication that we feel comfortable in our own cognitions and do not (very often) feel the need to create any reifications of them online. " It's a good thing Karl doesn't post just because he needs to bolster his ego or to create online reifications of his cognitions... "We seem to be under some delusion that the Arctic sea ice is somehow not going to refreeze..." Who is "we", then? We should thank Karl for illustrating so clearly why projection is so comforting to ones cognitions. Textbook example, I'd say. :-)