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Kevin McKinney

Yes, I was wondering where Lodger has been, too!

Account Deleted

Some of the latest information about the state of ice at the North Pole.

http://translate.google.ru/translate?hl=ru&sl=ru&tl=en&u=http%3A%2F%2Fbarneo-polus.livejournal.com%2F
March 24, 2012
The coordinates of ice, which will be "Borneo": N 89 ˚ 35 'E and 125 ˚ 46'.
For two days we came across a short (no more than 800 meters), the thin (60 cm) blocks of ice. Only in the evening (Moscow time) managed to find a suitable site on the pack ice.

March 23, 2012
Alas, today the search for ice is not successful. Open water and leads there, but a lot of ridges. The greatest distance between two hummocks - 600 meters, and the need for the construction of the runway a mile, to fight the same with hummocks - a very time-consuming job. Tomorrow, the radius of the helicopters will take more and will be again systematically obletyvat space.

March 21, 2012
As reported by the pilots of IL-76, this year in the pole a little open water, a little "rivers." Ice conditions can hope for a strong selection of ice under the "Borneo."

Account Deleted

"river" is a big frozen crack. A good place for the construction of the airfield (flat surface).

Apocalypse4Real

Something to note in relation to the comments above.

The Russian MYI thickness charts are showing that we are almost at a point that MYI is no longer over the pole (90N). Note the difference between the 1 Nov 2011 chart:

http://www.aari.ru/odata/_d0015.php?lang=1&mod=0&yy=2011

And the 20 March 2012 chart:

http://www.aari.r0u/odata/_d0015.php?lang=1&mod=0&yy=2012

The US Navy sea ice thickness map is showing a similar current state:

http://www7320.nrlssc.navy.mil/hycomARC/navo/arcticictnowcast.gif

If the Russian drift continues we may have thinner ice over 90N and open water at sea ice minimum.

A shift toward negative AO may become more sustained through spring, and contribute to more rapid warming.

Today's temps in south Greenland are perhaps a precursor of more warmth to come.

http://www.uni-koeln.de/math-nat-fak/geomet/meteo/winfos/synNNWWarctis.gif

Tor Bejnar

Matt, the fellow attempting to circumnavigate the Americas solo and non-stop, is now northeast of Puerto Rico (in the Caribbean) on the last leg of his journey ( to Annapolis, Maryland, USA). You may recall he is raising funds for a nonprofit sailing program for people with disabilities. I first learned of his adventure from Neven's blog when Matt was entering the Arctic last July. You can read Matt's blog at www.solotheamericas.org .

Derek

I suppose this is mostly methane. They dont seem to have any idea how to stop it and this gas leak may last weeks.

I dont suppose the hydrogen sulphide will help remaining North Sea fish much.

http://www.bbc.co.uk/news/uk-scotland-north-east-orkney-shetland-17505448

Al Rodger

As it sometimes does, SkepticalScience's weekly review of scientific papers this week links to the abstracts on things chryospherical. One of the papers however looks at a subject that has had me scratching my head for a while now - Why do models still predict an ice-free summer arctic ocean such a long way off into the future?

'The present strong trends in above model predictions are likely down to natural variation,' is the best explanation I have gleaned to date.

So the paper -
September Arctic sea ice predicted to disappear near 2°C global warming above present - Mahlstein & Knutti (2012)
http://www.agu.org/pubs/crossref/pip/2011JD016709.shtml
looked like providing a better explanation. Well it did in that the abstract says the models underestimate melt per rise in Arctic temperature and also underestimate Arctic temps as a function of global temps. With this and the observation that Sea Ice Area decline is roughly linear with Arctic temps, they conclude (as their title suggests) with a prediction of ice free summers when global temperatures exceed 2 deg C above present, an event that is surely still many decades away! Arctic natural variability is large, they say.
May be so, but I'm still left scratching my head.

Other chryospherical papers linked at SkS this week
http://www.skepticalscience.com/new_research_12_2012.html
Schneider & Noone (2012) who are examining a reported bi=polar seesaw anomaly.
Kim et al. (2012) who evaluate the implications of a longer non-frozen season in the Northern Hemisphere.

Neven

Yes, on first looks that Mahlstein and Knutti paper seems mystifying. I found a poster here. Is the decline of Arctic sea ice volume also linear with temps? Besides, it's high time we start seeing that high Arctic natural variability kicking into action.

Bob Wallace

This a very 'back of the envelop' analysis, but I think it addresses the statement "Arctic natural variability is large".

Gathering data by looking at the curves in the 'daily death spiral' graph I see that the 1979-2001 average annual minimum volume was 14,000 km3.

In 2002 the minimum volume was 11k, a drop of 3k. Following the baseline average the annual series changes run (roughly) -3, -1, 0, -1, 0, -2.5, +0.5, 0, -2.5, -0.5.

Variability, yes. But almost all change is downward. There's no "recovery" movement in the numbers. One +0.5k doth not recovery make, it only slightly stretches the time to total melt-out.

https://sites.google.com/site/arctischepinguin/home/piomas/piomas-trnd4.png

--

Furthermore, it seems that if PIOMAS was underestimating the thickest ice then melt has been worse than the PIOMAS data shows.

Thicker ice is multi-year ice and we've clearly lost a large amount of multi-year ice as evidenced by the growing amount of open water over the time frame. A lot of that 'under-estimated' thicker ice is no longer in the mix.

idunno

Hi all,

New article in New Scientist, summarising new unpublished research:

http://www.newscientist.com/article/dn21626-arctic-sea-ice-may-have-passed-crucial-tipping-point.html

Also, from the side-bar...

http://www.marketwatch.com/story/nrl-scientists-optimize-arctic-sea-ice-data-products-2012-03-26

...seems very relevent to ongoing discussions here about PIOMAS/thickness.

Wayne Kernochan

More on methane (and related carbon effects) ...
http://www.telegraph.co.uk/earth/earthnews/9168055/Compost-bomb-is-latest-climate-change-tipping-point.html

crandles

Prof T.M.Lenton's tipping point session information can be found at:

http://www.planetunderpressure2012.net/pup_session.asp?19044

"In particular, early warning signals were present prior to the abrupt retreat of Arctic sea-ice cover in 2007, and these signals have strengthened since"

Now why do I doubt these signals were early enough to cut GHG in time ;o)

L. Hamilton

Not Arctic, but a "local cryosphere" image: ice out day on Lake Winnipesaukee, New Hampshire's largest lake, occurred a few days ago. This tied the previous record for earliest ice out set in 2010.

An early or late ice out date in any one year is just weather, but 126 years are enough to see climate:

http://img.photobucket.com/albums/v224/Chiloe/Climate/lake_win_2012L.png

crandles

If interested in Atlantic Meridional Overturning circulation, you might want to take a look at:

http://www.climateprediction.net/board/viewtopic.php?f=60&t=9861&p=98339#p98339

Account Deleted

Now why do I doubt these signals were early enough to cut GHG in time ;o)

Even if these signals were obvious and early enough, at best all we would do is organise a UN gathering/convention to show we are doing something about it, and then ignore the problem.



Apocalypse4Real

There is a new study out by the Wegner Institute that suggests Arctic permafrost meltdown has already begun. It is based upon ESA satellite data.

http://summitcountyvoice.com/2012/03/28/global-warming-tracking-permafrost-meltdown/#more-39970

Account Deleted

any links to what the results of this conference is showing (rather than a dodgy press release)? The links in the article lead to vague discussion of this potential problem, rather than recent results

Wipneus

Oceanic Physics professor Peter Wadhams writes an open letter to the EAC. He criticizes Metoffice Prof. Dr. Julia Slingo's "skepticism" of the PIOMAS volume data (and projections).

http://arctic-news.blogspot.co.uk/2012/03/open-letter-to-eac-in-response-to-met.html

Prof Slingo starts out by saying that the projection of an ice-free summer in 2015, as earlier presented by Prof Peter Wadhams, is actually more credible than the modelling done by the Met Office. This remark may have been a slip of the tongue. Prof Slingo continues to rule out such a date and also rejects PIOMAS data showing an Arctic sea ice volume decline by 75% (from over 17,000 cubic kilometers before 1980 to around 4,000 cubic kilometers now). When asked to elaborate, Prof Slingo says: “We don’t know what the thickness of ice is across the whole Arctic with any confidence”, and “We know there is some thinning but it is not as dramatic as those numbers would suggest.” Prof Slingo also says that the observational estimates of sea ice volume are “still very uncertain”.

It is not good scientific practice to use uncertainty - even if it was there - as the basis for ruling something out. Moreover, Prof Wadhams’ conclusion is supported by years of direct observations of the decline of sea ice volume from submarines, taking away much uncertainty, while Prof Slingo doesn’t add any convincing evidence to the contrary.

I was puzzled before what Dr. Slingo knew about ice volume that we did not:

http://neven1.typepad.com/blog/2012/03/piomas-march-2012.html?cid=6a0133f03a1e37970b016763a8a2d6970b#comment-6a0133f03a1e37970b016763a8a2d6970b

Kevin McKinney

Very interesting! That's quite pointed, to say the least.

Peter Ellis

Well, it's clear that Professor Wadhams, as with many others, is concerned about Arctic methane.

To some extent I think the debate is one between personality styles, rather than a scientific debate. At RealClimate a few months back, there was a well-argued post which showed that the worst-case effects of an unknown, uncertain, uncontrollable methane release are essentially comparable to the known, certain effects of continuing current CO2 emissions. I've seen no argumentation from either side to dispute this.

This being the case, there's a choice to make. Do you spend your time and energy raising awareness of the methane threat, on the precautionary principle that we need to take additional care in an area with such large uncertainties, and no means to "rescue" the climate if the release process starts in earnest? Or do you not bother with the stuff we can't do anything about and concentrate effort on the areas where we might actually be able to make a difference?

I suspect there's a fundamental physiological difference (at least partly genetic) between those who worry more about stuff they can't control, and whose who worry more about stuff they can control. Neither side is necessarily wrong, but never the twain shall meet.

Ironically, both camps, no matter their differences, lead to the same behavioural prescription: an all-out worldwide program to decarbonise energy production. Which won't happen.

<sigh>

FrankD

Prof Slingo starts out by saying that the projection of an ice-free summer in 2015, as earlier presented by Prof Peter Wadhams, is actually more credible than the modelling done by the Met Office. This remark may have been a slip of the tongue.

I think Prof Wadhams is incorrect in this claim. Prof Slingo said:
Our assessment, based on the latest climate model simulations that have been performed for the Fifth Assessment Report, suggests some time between 2030 and 2080. Our own model would say between 2040 and 2060, and it is fair to say that our view is that the earlier dates-in other words, the more pessimistic outlook for the Arctic-are associated with models that we believe are more credible, in terms of their capability to reproduce the observed seasonal cycle in sea ice extent, and also the variations in sea ice from year to year. Our expectation is certainly not in the next few years, as I think you have heard from some evidence, but within, say, 2025 to 2030 would be the earliest date.

It appears to me that Prof Slingo is saying that while the range 2030 to 2080 is generally accepted, the most accurate models suggest the earlier end of that spectrum. She is referring to the "more pessimistic outlook" within the band she is discussing, not the most pessimistic of all models, which is how Prof Wadhams seems to have interpreted it.

Be that as it may, apart from the uncertainty defence Prof Wadhams complains of, I see two other flaws in Prof Slingo's response:
1. She attempts to reject the output of one model by invoking the output of another model. Now, if she had compared the merits of those and other models in their demonstrated predictive skill that would be one thing, but all she really conveyed in her argument was "My model's better than his." It comes across as an argument from personal incredulity, which issimply fallacious.
2. Prof Wadhams advanced an argument that we have discussed at length here - "Its all very well to talk about extent, but if ice is also thinning then the 3-d situation is much worse than appears in 2-d models". Prof Slingo responds to this by first conceding ice is thinning, but then saying in effect "Our 2-d model shows the problem is not as serious as their 3-d model suggests." Which is simply self-referential handwaving; it doesn't answer the criticism, it simply attempts to turn it on its head.

Wayne Kernochan

@peter ellis: I think that this is not where the divide in the argument lies. It's mostly off topic (arctic), but hopefully I can summarize.

According to what I've seen, methane comes from human-caused plus not. The not divides into three areas: Arctic near-shore (20-1000 feet), Northern permafrost, and other (mostly peat bogs all over the world). It appears that the Arctic near-shore is somewhat less in amount than the other two. Recently, it was found that the near-shore 20-100 feet could vent and was venting far more rapidly than expected. Also, it apparently has also just been found that the permafrost is more in amount and is likely to vent more rapidly than expected (cf my last post).

The effects merit the notion of "tipping point". At some point, the effects of enough methane in the atmosphere become non-linear -- perhaps around a total "not" source increase per year equal to present human-source methane. Methane reaches a saturation point in the atmosphere and hangs around for much longer (now, it's 9 years) without being converted to CO2 or returning to earth -- and it has much stronger warming effects than CO2. That warming, in turn, speeds up "not" methane production further. Eventually, after 200-1000 years, the "methane bomb" ends -- leaving perhaps 50% more CO2 for another 200 years than would otherwise be the case.

Carbon is driving the arrival and initial speed of the "methane bomb". So all sides agree that carbon reduction must take priority. The argument is political: whether reductions in human-source methane (which will reduce the "methane bomb" likelihood only minimally) are a case of "every little bit helps when politicians won't do anything about carbon reduction" or a matter of "you're distracting politicians from carbon, delaying our reductions."

crandles

>"Now, if she had compared the merits of those and other models in their demonstrated predictive skill that would be one thing"

Fair enough if that was possible and had been done then not explaining the outcome of comparison of predictive skill would be a very odd omission.

But what if predictive skill cannot be compared on a like for like basis because Wadhams model is simply a curve fitting to volume exercise whereas met office model is a complex GCM? She mentions "capability to reproduce ... variations in sea ice from year to year" which a curve fitting exercise is hopeless at. Is it then reasonable to express some personal opinion/incredulity over whether the simple curve fitting exercise is better? e.g. "My model is more comprehensive than his."?

So I think I would be inclined to reject Frank's criticism 1.

Is a better criticism to throw at the evidence she presented as follows:

>"more pessimistic [end of 2030-2080 range] ... more credible"

Is that an unfair summing up of situation if the reality is that the observations are actually more dire than all the models Prof Slingo is discussing as in

http://www.realclimate.org/images/seaice11.jpg

Steve Bloom

Has there been discussion here of this new paper (html full text here) making the case for Arctic sea ice reduction driving an increase in blocking events? A site search turned up a link to a Dosbat post on a ppt by the lead author, presumably covering the same material (I need to look), but nothing on the paper itself.

sarc/

But, truly, what's to worry about? I mean, it's not as if the entire ocean-atmosphere circulation is shifting or anything, right? Oh wait...

/sarc

Steve Bloom

Related article in yesterday's NYT. Christy and Hoerling were dragged out for balance.

L. Hamilton

Cycle plot of Antarctic sea ice extent by month, 1973-2011 (Uni Bremen data; this is their whole southern record):
http://img.photobucket.com/albums/v224/Chiloe/Climate/Cycle_Antarctic_extent_3.png

Outliers are conspicuous in these data so I applied robust regression to fit trend lines and test significance. Significant increases occur only in three austral winter months: July, August and October. In January (austral summer) ice extent significantly decreased. Other months show no significant linear trends.

Neven

Thanks for that NYT article, Steve. I had seen the headline, but your comment pushed me to read it. Interesting read.

Kevin McKinney

"...because Wadhams model is simply a curve fitting to volume exercise..."

I think Dr. Wadhams is operating on the basis of the output of Maslowski's Naval Grad School Arctic ice model--I know that Dr. Wadhams has referred to Maslowski as "the best modeler around." (WRT to Arctic sea ice specifically, one presumes.)

FrankD

Everything after "be that as it may" refers to other parts of her submission - specifically her responses to questions 118 and 119. Rather than quote at length, I suggest consulting the source material.

Question 118 asks arout the 75% volume loss that Prof Wadhams claims. Note that this figure is not from any curve fitting, but is simple output from PIOMAS comparing early data with recent data. Prof Slingo responds by talking about extent, hence my 2-d -v- 3-d criticism.

Question 119 presses for more and she responds that their model does not bear out a 75% figure.

Fine, but on what basis should we prefer the Met model to the PSC model? That IS what is being compared...

Finally, a third criticism: "we do know there is still a lot of multi-year ice there. "
Well, of course "a lot" is a completely subjective figure so there is plenty of wiggle room, but is there anyone studying the cryosphere who would serious accept the claim that there is "a lot" of multi year ice around?

FrankD

Sorry - the post above lost its first paragraph in edit. Should have opened:

crandles, you've misunderstood "Franks criticism 1." due to my lack of clarity - the section I quoted in my post was only to explain why I think Wadhams claim about endorsing his 2015 date is wrong.

Everything after "be that as it may"...

crandles

OK, my inclination was wrong. Sorry, I should have referred to the source.

Al Rodger

There's a big long post by Tamino over at Open Mind
http://tamino.wordpress.com/2012/03/29/to-robust-or-not-to-robust-that-is-the-question/ inspired by L Hamilton's graph of 'Antarctic Sea Ice Extent trends by month' linked a few comments back up this thread.
The bulk of Tamino's post is describing various considerations when calculating linear trends (interesting for those who appreciate the working of the statistics).
However the end-game is L. Hamilton's graphing which shows the early years of the Bremen data giving much larger extent figures than the rest of the data. Tamino suggests this data is not due to 'noise' or 'outliers' but provides a link to a graph of ice extent which includes 'estimates prior to 1973' (data source unreferenced) which suggests Antarctic Sea Ice Extent was dropping rapidly up to the mid 70s with far bigger drops then than any change since (although Tamino admits he has not a source for the actual Bremen data).
http://tamino.files.wordpress.com/2010/10/shem140.jpg Tamino's source may be well known to students of things Antarctical (but it is not to me).

me.yahoo.com/a/nSjChi4X3vr8X3DRw93GkY1.cerja.8nvWk-

Check out fig 2.16 in the IPCC Tar.

Phil.

Neven

Here's a link to that TAR fig 2.16.

Al Rodger

Thanks Phil. Direct link to a page showing TAR fig 2.16 http://www.ipcc.ch/ipccreports/tar/wg1/062.htm

This is the post-1973 data with the high early values for extent that Tamino's graph (link at 2 comments above) shows as part of a bigger feature of high extent back into earlier decades.
It occurred to me given the link URL that Tamino's graph may feature in a 2010 Open Mind post & here it is derived from HADISST http://tamino.wordpress.com/2010/10/16/history-of-arctic-and-antarctic-sea-ice-part-1/

L. Hamilton

The the 1972-1978 UB Arctic extent values, graphed in Figures 4, 5, 6 here,
http://neven1.typepad.com/blog/2011/10/september-2011-sea-ice-extent-looking-back.html
do not exhibit the very high early-70s values I keep seeing in the earlier datasets linked above. On the contrary, the UB 1970s look well behaved up north.

But the 1973-1978 UB southern values look less well behaved,
http://img.photobucket.com/albums/v224/Chiloe/Climate/Cycle_Antarctic_extent_3.png
showing anomalously high *and* low values in the first few years.

Are those values accurate? If accurate, do they reflect climate or weather? I dunno, and not knowing seemed a good reason to use robust regression, which downweights occasional wild observations.

Robust regression itself became the topic for Tamino's next post.

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