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Chris Biscan

Not to brag, but I have been tracking this and calling it all winter.

More importantly, we can track the sea ice at a high level, some skeptics/deniers pretend our technology is not what it is to defer from reality.

But just from watching the weather, and a few sea ice products it was easy to see that happening.


Hi all,

The many clueless:


Has a lot of interesting information... for psychiatric research professionals.


Map in post seems fairly similar to


The graph does seem to have a little downward acceleration unlike feb extent trend.


but it isn't much downward acceleration compared to September extent trend


I think that is probably as expected with the most loss of ice being from ice thickness and southerly first year ice extent.


Not to brag, but I have been tracking this and calling it all winter.

And so you did, Chris. Kudos to you.

But it's nice to see it quantified in terms of total MYI left at the start of the melting season.

Has a lot of interesting information... for psychiatric research professionals.

As the ice melts more and more, the walls of denial crumble more and more. It hurts. It burns. Nevertheless, I was surprised to see this outburst. It gets picked up though by the dutiful ignorati.

It's best to ignore the ignorati.

Account Deleted


"So little ice has never been seen before." In fact, scientific exploration that took place in August 1922, sailed in open water all the way to 81° 29 minutes North in ice free waters. This was the "farthest north ever reached with modern oceanographic apparatus."

This is not true.

In 2005, the scientific ship (not ice-breaker) for the first time in the world has reached the North Pole.

"29 августа. Флагман российского полярного научного флота "Академик Федоров" стал сегодня первым в мире транспортным судном, которое самостоятельно, без сопровождения ледокола, дошло до Северного полюса, передает ИТАР-ТАСС.
Вице-президент Ассоциации полярников России Владимир Стругацкий заявил, что "вершина нашей планеты была достигнута в 18:50 мск в ходе уникальной высокоширотной экспедиции "Арктика-2005".

Account Deleted

During the past warming in the Arctic in the 30th years of record for free diving sea was 83 north latitude.

"Летом 1938 ледокол "Ермак" сумел пробиться к дрейфующим судам и подошел к ним в точке 83°04,8 с. ш., 138°02' в. д., установив рекорд свободного высокоширотного плавания."


"It’s nearly back to within one standard deviation of the 30 year normal at 14.25 million square kilometers."


Can they not read this graph saying 2 std deviations or is it just their opinion that 2 std deviations is "nearly back to within one standard deviation"?


Hi Articicelost80,

Sorry to say that information in Cyrillic is infolost on me. If you can understand this, a very warm welcome; IMHO this blog is lacking only a Russian correspondent.

The area of ice-free water North of Svarlsbard extends North of 81,29 today, on 1 March:


crandles: I think this is the graph which shows +/- 1 SD:


Nearly there!

Other gems: summat about Atlantis in the comments thread; also, Marco Polo went to the North Pole. A second North Polo hypothesis!

We're promised an update on Arctic history from tony b: for those who missed the first one, he goes through the journals of, say, an expedition that took 3 years to penetrate as far North as the top of Baffin Bay, looking for any entry that says anything about a variation in ice conditions. Then goes, "See, its all very cyclical...".

Finally, there seems to be an emergent meme that the Arctic was ice-free in the early Holocene. I haven't really investigated this, and it would be interesting, if true.

I suppose the good news is that, IIRC, sea level rose 120 metres in the early Holocene, and it can't rise that much now, unless we start importing land ice from Mars.


If the entire Arctic was ice-free (which is far from settled) during the Holocene we have a very good idea of the cause: a change in axial tilt that "provided 8% more solar radiation (+40W/m²) to the Northern Hemisphere in summer" (Wikipedia). We know this isn't the case now.

Janne Tuukkanen

I suppose it's possible, even probable, we had ice free arctic basin summers during the optimum. This should be clearly evident from sediment cores, which however I've heard nothing.

And as Neven said, the causes of Holocene Climatic Optimum are well understood nowadays.

Account Deleted

Hi, idunno.

Use Google translator. I'm using it well understand the English texts.

I was looking for information to compare the ice in the Arctic over the past 400 years.

Among the skeptics, this figure goes:
This location of the northern boundary of the ice in August in the Strait between Svalbard and Franz Josef Land from the reports of whaling ships.

But the schedule ends with 1998. Well, we have different cards and we can define this boundary in the 1999-2011 years in mid-August.

For example there
http://www.iup.uni-bremen.de:8084/amsr/Icefilm_Arc tic.avi

As a result, I get:
1999 82,0
2000 81,0
2001 82,0
2002 80,0
2003 80,5
2004 83,0
2005 81,5
2006 82,5
2007 81,5
2008 80,5
2009 80,0
2010 81,0
2011 83,5

So I can conclude that the boundary of the Arctic ice in the 21st century, the northernmost in the past 300-400 years.


A change in axial tilt? Wasn't it perihelion and northern summer coinciding 10000 years ago?


AmbiValent, according to Wikipedia it was both. I'm basing myself on the excellent scientific explanation by Richard Alley. Everyone understands now, except Dana Rohrabacher.

Chris Reynolds

Hello all, I've just posted something I've been pondering about for months. I think it complements well with Neven's main post.

What happened in Spring 2010? Was there another sea ice crash as big as 2007?

Chris Reynolds


Jakobsson et al finds that sea ice was reduced and there MAY have been periods that were sea-ice free in Summer. This is important becaus it suggests that if we seriously reduced emissions the loss of sea-ice would prove to be reversible. Although various modelling studies looking at the transition to a year round sea ice free state find that there may be 'tipping points' during that next transition, e.g. Eisenman "Factors controlling the bifurcation structure of sea ice retreat".

Jakobsson, 2010 "New insights on Arctic Quaternary climate variability from palaeo-records and numerical modelling."

Chris Biscan

First, I want to give a sarcastic thanks to the link on the Watts blog. Reading so many tools write their unfactual opinions after there spin master god Watts posts is an ego boost.

Second, it is a huge letdown to see how stupid and flat ignorant of fact, conception, and the ability to read many of those folks have issues with.


That NASA MYI thing is for Feb of 2012, not Sept of 2011 which Watts used Steven Goodard(the dumbest blogger on any side of of any climate debate ever). We had more 2nd and 3rd year ice in September of 2011. Since then the pattern has been one to flush a ton of it. Guess what Mr WATTS? It was flushed and melted.

To know this, all it takes is to spend 30 seconds everyday looking at current SLP conditions in the arctic, gee so hard.

Have any of the tool sheds over there read Walsh & Chapman?

Do any of them understand ice core dating? Or Permafrost dating? Where they have found plants 40K years old in Alaska frozen?

Do they not understand glacial melt has been going on at an accelerated rate for over a century?

Do they not understand albedo?

Snow albedo feedback?

Ice albedo feedback?

Greenlands SW/W side is getting awfully close to a rapid albedo feedback in summer when we see melting double, triple and so on.

What does Professor Watts and his minions think will restore glaciers and the arctic MYI ice that was 7-12M at the core? Or the ridged ice in the Canadian waterways that was 50-200M deep in spots?

I am just so fed up and sick of the lies and bullbleep.

Kevin McKinney

I sympathize, Chris. It is amazing.

You do know, though, that for most of your questions the answer is no, they don't know. (And take care not to learn.)




Hi Chris Biscan,

If you really want a site that doesn't understand albedo, I can recommend today's top posting from:



Idunno wrote:

a site that doesn't understand


It's not so much about understanding but about a hidden agenda. But you do know that, don't you? :-)

Kevin O'Neill

@ idunno - the really ironic part of SG's post over at Real Science is that it's linked to an article about research results from Georgia Tech (Judith Curry). And the research says exactly what deniers refuse to believe - the loss of arctic sea ice is changing circulation patterns and causing some of the anomalous heavy snows and/or cold winters recently experienced in parts of the NH. Then in the comments they twist it to mean exactly the opposite.

Ignorant, stupid, evil or insane? Take your pick.

Chris Biscan

I don't care what credentials that Mr. Steven Goodard has. He should be embarrassed to be a homo sapein. And take shame for lowering the bar on Intellectually honesty, ethics, morals, integrity, dignity, and I am sure a host of other bad things.

While he may suffer greatly and have the Dunning-Krugger Syndrome or affect, whatever you call it. He is still a grown man who is acting completely against the best interest of our species and this planet. He also makes a complete mockery of science. I have no idea how a man such as this can sleep at night with any sort of clean conscious.


Kevin wrote:

Ignorant, stupid, evil or insane?


I wonder.

For example, the harsh Russian winter in Moskva and the whole region between Saint Petersburg and the Ural begins "normally" around 1 december and ends even "normally" in the last weeks of March.

Now, to prove his "point" he tries to persuade the readers the winters begin there at the 25th of January.

You can be stupid, but you can't be that stupid, can you? - He very well does know the harsh winters in Euro-Russia usually take off in the first week of December.

So, imho none of the "epithetans ornans" you mentioned do match this person.

But, still imho, a more consistent description would be "a person loving scheming" or a person with a malicious mind. Someone with a hidden agenda.
He claims he is not being paid, but we better don't believe the first word of it.

Bottom line, let's take Neven's advise and let's keep ourselves away from his website and it's "anomalies". It isn't even worth the electron particles we are spoiling on it now.

A proposito, you can monitor the situation in Moskva every houre here:


The river Moskva remained open till the 27th of January and is at this moment virtually defrosted.

Which means it has been a very normal winter there, as everywhere in Europe except for Italy, Greece and the Balkan regio.

"Normal", but with the average temperature above normal.


At this point, one could explain things with Christian Morgenstern:

The Impossible Fact

Palmstroem, old, an aimless rover,
walking in the wrong direction
at a busy intersection
is run over.

"How," he says, his life restoring
and with pluck his death ignoring,
"can an accident like this
ever happen? What's amiss?

"Did the state administration
fail in motor transportation?
Did police ignore the need
for reducing driving speed?

"Isn't there a prohibition,
barring motorized transmission
of the living to the dead?
Was the driver right who sped . . . ?"

Tightly swathed in dampened tissues
he explores the legal issues,
and it soon is clear as air:
Cars were not permitted there!

And he comes to the conclusion:
His mishap was an illusion,
for, he reasons pointedly,
that which must not, can not be.


I really used to appreciate this site for reporting the data around arctic ice, but recently there seems to be more of an agenda to push political rather than scientific arguments, descending even into personal attacks.
A great shame as it, in my opinion, diminishes the scientific credibility of Neven's excellent site and makes it less available as a data point for teaching my students. Could we have just the facts and leave the dogma to all the other climate sites, AGW or Warmist?


Karl, I appreciate your comment, but you have to understand that some of the frustration needs to get vented a bit every once in a while, especially when provoked by Arctic Gish Gallops à la Watts (which would be an interesting data point to teach students about cognitive pitfalls).

The current situation in the Arctic is pretty serious, and if continued, does not bode well at all. People still denying that, raise hackles.

Other than that I don't think we're doing so bad over here. It's 95% about the Arctic. Nobody can help it that things look alarming up North.


Hi Karl,

If you direct your students to ignore any thread where you have left a comment - this one and "a word from our sponsors" - that should be sufficient to avoid exposing them to any politics.

Most all of the rest is as scientific as we can manage.

Having said this, I read an awful lot about the Arctic elsewhere, and I feel it is quite legitimate for me, or anybody else, to highlight and discuss other sources of both information and disinformation in regard to Arctic sea ice here.

Janne Tuukkanen

I think Karls is partially right. This has been one of the sites, which has not been succumbed in shouting matches. So, let's Arctic Ice (or what's left of it) cool us down, however frustrated or whatever we feel :)



The wesbites posted by Arcticicelost80 area as follows:

The first is from a Russian news clearinghouse and reads:
August 29 [2005]. The flagship of the Russian Polar Research fleet, "Academician Fedorov" has now become the world's first transport ship to reach the North Pole alone, without icebreaker escort, ITAR-TASS reported.
Vice-President of the Association of Russian Polar Explorers, Vladimir Strugatsky said the "top of the world was achieved at 18:50 GMT in a unique high-latitude expedition "Arctic 2005".

The second is a Russian Navy page dealing with a 1938-1940 expedition by three ships drifting through the pack. The made occasional rendezvous with other ships and aircraft and the paragragph AIL80 quoted reads:
"In the summer of 1938 the icebreaker "Ermak" managed to get through to the drifting craft and approached them at 83°04.8'N, 138°02'E. In doing so, she set a record for high-latitude free navigation." ("free" in the sense of a ship making her own way, as opposed to the three drifters).

Chris Biscan

I apologize Karl.

I can also assure you that this Bias of this blog does not affect the presentation of said data. While the attitude may reflect one of which that leans towards what deniers would call gloom and doom, then yes this place would be guilty as charged. Watching gigantic ecological changes occur over a radically short time can invoke such concern in most rational human beings.

With that said this place does an amazing job with breaking down the data. And analyzing the facts.

Most of us are very interested in the science of this and have done far to many hours of research. Then if you are a student of science you fact check the data. Spend far to many hours looking for every data need you can think of.

Luckily it is 2012 and we have satellites covering everything. Well except ice thickness :). But it's really easy to learn climate science, then use the data we have to follow it and understand it.


Based on the ECMWF weather forecasts I now think that the maximum will be reached tomorrow March 5th (give or take two days). CT SIA lags a bit, so we'll know around the 10th whether I called the maximum correctly.

According to the current forecasts the situation in Barentsz/Kara and Bering/Okhotsk that reverses ice growth is going to last a couple of days. It's going to be very interesting to watch.


on the arctic being ice free in the holocene, i remember reading [70s] about the first explorers to the new siberian islands finding mammoth tusks stacked as if for shipping and also forming simple 'ribbed' structures that had long since lost their skin covering. So i googled 'mammoth tusks on new siberian islands, after trawling no joy but these are the most interesting sites and well worth a look if you have the time.[stomach contents indicate climate] http://s8int.com/boneyard4.html
Neven the second[scientist] speaker in the second link of your 21:08 comment speaks what i think is about to happen - a warm current bathing the the shore of the laptev sea with the fresh water driven out by way of the western european coastline.

Chris Reynolds

I need some help.

I want to use the data from this link, I got it from this blog.


The problem is I can't find the documentation or source page for it. I'm pretty sure that column 3 is area, column 4 is extent, but can't figure out column 2.

Can anyone explain or point me to the documentation?


Hi Chris,

All are area, not extent.

Column 2 is anomaly.

Column 3 is actual reading.

Column 4 is 1979-2008 average.


Chris Reynolds

Thanks Idunno,

Just popped back to say it obviously wasn't what I was expecting as column 4 has a high degree of repetition. at least I have area.

Has anyone got a link to daily extent 1979 to present? My previous forays into NSIDC data got me nowhere.



I could be wrong, but I believe 2+3=5. Yes, I'm reading science papers now. ;-)

Nightvid Cole


In what sense could you be wrong about 2+3=5? Not logical possibility, because 2+3=5 is a pure mathematical truth...


There is IJIS/JAXA data that only runs runs from mid 2002 to 3 Oct 2011:


There is also GSFC data from 1972 to 2002


I attempted a correction to GSFC data to make it more comparable to IJIS:


Sorry, I'm not aware of any generally available extent figures post 3 Oct 11.

In what sense could you be wrong about 2+3=5? Not logical possibility, because 2+3=5 is a pure mathematical truth...

I'm not putting anything past myself, NC. But 'twas mostly a joke. :-)

idunno meant column 2 + column 3 in the CT Arctic SIA data = column 4


Just because I am aware of university level maths courses that take a whole term to prove that 1+1=2, doesn't necessarily mean that Neven has done such a course or even if he has that the course has proved it to Neven's satisfaction.

Or maybe Neven just distrusts his memory of basic arithmetic.

Or ....

How many examples did you want? ;o)

(Column 2 plus column 3 figures do appear to add up to the column 4 figure in the data being referred to.)


Crandles wrote:

term to prove that 1+1=2

That can't be proved, can it? That's why this equasion has been established as an axioma.

And maybe wrong an axioma. As in the end we even can't imagine something like 2 exact equal particles. One molecule of water differs from the other molecules of water, one H atom differs from the other Y atoms, one electron differs from the other electrons, one quark differs from the other quarks. And when we explain electrons and quarks just as energy we even can't think about an equasion ....

Maybe 1+1 isn't equal to two. Maybe that's why in the ends science meets again and again new
limits to overcome. :-)


Erroneously I wrote:

one H atom differs from the other Y atoms

That should have been "one H atom differs from the other H atoms"
of course.



378 pages and almost there ...

... until Godel caused it all to collapse.

I didn't think my maths professor was joking when he talked about a course taking a term over it. But I could have misinterpreted what he said.

>"one H atom differs from the other H atoms"

I though mathematics occupied an idealised plane of thought that wasn't troubled by physical world inperfections where one H atom may not be the same as another H atom. A world where proofs are possible while mere sciences are limited to evidence....

Kevin McKinney
In what sense could you be wrong about 2+3=5? Not logical possibility, because 2+3=5 is a pure mathematical truth... I'm not putting anything past myself, NC. But 'twas mostly a joke. :-)

idunno meant column 2 + column 3 in the CT Arctic SIA data = column 4

Aha! The 5 is *corrected*!

But thank you for releasing the data and algorithm; we are, of course, all for transparency in blog science...


Crandles wrote,

I though mathematics occupied an idealised plane

Quite right.

And that was one of the reasons the academics never liked Einstein, as he always kept an eye on reality.


Haven't found an axiom for 1+1=2 in http://en.wikipedia.org/wiki/Axiom

Guess I should admit that I am really not sure what we are talking about.

It seems quite plausible that the definition of 2 means that 1+1=2 cannot be proved without the proof simply being a simple rearrangement of the definition. Meanwhile any talk of proving 1+1=2 is merely a simple way of expressing a much grander framework idea that does take a lot more proving.

OTOH perhaps it isn't some grand framework idea and it is more about proving simple additions with larger numbers eg this comment:

"Well, if you want an actual formal proof, see the metamath proof of 2+2=4. (1+1=2 is boring because that's how it defines 2.) This is a really nifty browseable hypertext of a computer-verified proof derived from the axioms of Zermelo-Fraenkel set theory. That is 5254th theorem in the system, although not all of the preceding 5253 are required for the proof. (In particular, number 1329, the Axiom of Choice, is not a prerequisite.)"


That doesn't seem like a term of work though 5254th proof might indicate there is a bit of work to do before you get there.

Anyway it seems to me that we need a definition of what needs proving before we can start.

Chris Reynolds

Thanks Crandles,

Very helpful as always.

If it's OK, I'm going to use your adjusted series - it seems pointless to reinvent the wheel when you've made a better one than I'd have done.


Chris R,

No problem using it, thats why I linked it. :)

I certainly wouldn't claim it is the best or most appropriate adjustment process for any particular use (let alone your intended purpose) but feel free to use it if you wish.

John Christensen

On the topic of 'normal' climate and how we deviate from history:
There is a lot of scientific material available from scientists, who agree with the current warming, but still point to a less than 'normal' climate history.
See this example from Atle Nesje in Bergen, Norway:
He has studied the history of the ten largest current glaciers in Norway, and found that in the past ten thousand years, at some point they have all completed melted away and then reappeared as precipitation and weather patterns have changed.
Some of the current glaciers have 'only' existed for about 4,000 years..
While I acknowledge that the climate is changing (is ever-changing) and that CO2 is part of the current warming, there still seems to be an overreliance on those few factors we understand to some extent, and a lack of true exploration to understand the bigger picture of climate change.
The tilt of the earth should not have played a significant role six thousand years ago, so what caused such a significant warming, and was this a global or regional phenomena?
To understand our current climate, we need to do much more than analyzing the minute changes that have occured over the past thirty years..
And for this spring; maybe the abnormal wind patterns that packed the sea ice on the North American side and reduced overall sea ice extent will help the packed/thicker layer of ice survive the summer melt better than prior years?

Not from a skeptic, but curious mind..


>"The tilt of the earth should not have played a significant role six thousand years ago"

Hmm., to an extent this is true and also what we should expect:

According to Wikipedia greatest heating to Northern hemisphere by 8% extra insolation would have been 9000 years ago not 6000 years ago. But it takes a long time to melt glaciers/ice sheets/thick ice shelves etc in order to get the full albedo effect. Not sure about 3000 years being an appropriate lag - I guess it depends on the thickness of the ice. But it will be some time after the maximum heating before the albedo effect increasing temperatures is matched by reducing insolation cooling temperatures.

Of course there are other effects and other lags on temperatures as well. Thawing perafrost would have released methane which decays to CO2.

With these other temperature effects e.g. from albedo, and greenhouse gas releases, it is not surprising that just looking at Milankovitch cycles 6000 years ago could lead to the impression that that alone is not enough to cause the temperature rise.

Being Northern hemisphere regional effect seems to be born out not only by temperature proxies but also by the ITCZ moving southward.

Now why do I feel I shouldn't have bothered posting this?

Bob Wallace

"Now why do I feel I shouldn't have bothered posting this?"


John Christensen

>"Now why do I feel I shouldn't have bothered posting this?"

Well, you should since it is interesting to know more about.

I agree that with the ITCZ moving southward as the earth entered the current warm period, preticipation patterns would shift, but the Norwegian geologist claims that findings show that it was somewhat warmer then compared to today.

Also, as seen on page 13 of the paper, the 'little ice age' that ended about 250 years ago, resulted in the glaciers of Norway reaching a combined maximum of the last 10,000 years, and they have retreated most of the time ever since back to what for that region appears to be 'normal'.

And this is my main point; If they could have Winter Festivals on the Thames two hundred years ago, and a 10K years glacier maximum in Norway, shouldn't we expect 'normal' to be warmer than that, and when do we acchieve that 'normal' climate? The Jacobshavn Glacier in Greenland has melted steadily since anyone cared to check (from 1851), and with the NAO normally resulting in oppositive weather patterns in West-Greenland compared to Northern Europe, this would indicate a move from a more expanded colder northern hemispheric climate to the current warmer climate.

It would be very interesting to see glacier mass and extent research from other regions, but so far the mass of research is focused on changes in the last 30-80 years.

If anyone is aware of research in this area, please share.



>>"Now why do I feel I shouldn't have bothered posting this?"


Yes exactly, sigh. Hit one issue and you can be sure another or a gish gallop of arguments will pop up. It soon looks like there is debate to anyone giving a casual glance.

Wayne Kernochan

Can I play?

@JC (why do those initials strike me as suspicious?): No they don't. Questionable. So what? Nope. Well, duh. About 160 years ago. No, it hasn't. No, it wouldn't. Not really, since there's plenty out there already. No it isn't. Read "The Fate of Greenland."

That was too much fun. I better get back to real work.

Andrew Xnn

JC; One reason why there is so much data over the last 30+ years is we only have good satellite data starting from 1979.


Hi, John.

To understand our current climate, we need to do much more than analyzing the minute changes that have occured over the past thirty years..

I agree, but also bear in mind that we see these minute changes (some not so minute, like the Arctic sea ice) all over the place now, from the Canadian Archipelago and its glaciers, to Siberia, from the Northwest Passage to the Northern Sea Route (both open 5 years in a row), whereas there seems to be evidence that many deviations in the past, such as frozen canals/rivers and glaciers the LIA, were mostly regional occurrences.

And for this spring; maybe the abnormal wind patterns that packed the sea ice on the North American side and reduced overall sea ice extent will help the packed/thicker layer of ice survive the summer melt better than prior years?

Definitely, one thing happening on one side of the Arctic, usually has the opposite thing happening on the opposite side. So I wouldn't be surprised to find out that ice in the Canadian Archipelago, Beaufort and Chukchi is much thicker than in previous years, with a nice buffer of ice in the Bering Sea and Strait to boot.

But in my opinion I made that sufficiently clear in the last paragraph of this post.

Janne Tuukkanen

John, I think you should write a comment about these matters into Skepticalscience. They have appropriate entry for Holocene, and people who might be familiar with the paper you are referring to:

Most of the last 10,000 years were warmer

Kevin McKinney

A paper discussing the Holocene Thermal Optimum:


(Kaufman et al, 2004. Kaufman et al. 2009 is also worth a look.)

John Christenson, you confuse me a bit. Your first comment talks about "less than normal climate history," and emphasizes the unknown (or supposed unknown):

...an overreliance on those few factors we understand to some extent, and a lack of true exploration to understand the bigger picture of climate change.

(I don't agree with either of these perceptions, by the way, but that would be a whole other comment.)

But then in the second comment you invoke the notion of a 'normal' climate:

...shouldn't we expect 'normal' to be warmer than that, and when do we acchieve that 'normal' climate?

I'd have thought that if we understand just "few factors... to some extent," then we can hardly claim the right to "expect" much of anything. As a corollary, why would we think that our current climate was either more or less 'normal' than the LIA?

My perspective, for what it is worth, is that there *is* no 'normal' climate. Viewed over long time spans, climate can be perceived as remarkably stable, considering--but that doesn't mean that there is some sort of pre-determined 'set point' which is 'normal,' and to which deviations must ultimately return. And if that view is correct, then there is no particular reason to think that cooling is particularly likely to "automatically" bring warming in its wake (or vice versa.)

Rather, climate (I think!) changes in response to specific forcings which affect the balance of energy into, and energy out of, the Earth system. If the Sun warms, the Earth will warm. If greenhouse gas concentrations fall to very low levels, the Earth will cool. And so on, for many, many combinations of forcings... it's a complicated picture because the Earth is complicated. Atmospheric circulation, oceanic currents, and biological processes can all do strange and wonderful things, some of which affect climate.

But I do think that by now we do have a pretty good grasp of what all the 'major players' are. That is, we will not, I am pretty sure, discover any more big factors directly affecting climate. We *will* discover more about how the players we already know go about playing the climate 'game'--how their individual natures and tendencies interact to create the flow of play.

It's a cheap play on words, I suppose--but I really think that we already know the score fairly well.

John Christensen

@Kevin; I completely agree with your observations on the concept of normal, which is why I put in it '..'; we have short- and longer term weather patterns, and then less predictable shifts in forcings and other variables, which together bring about climate changes, and very possibly the end of the 'little ice age' was caused by some change in external forcing.

However, since most likely both NH glaciers and Arctic sea ice has been retreating for some time (100-200 years depending on the region), this environmental shift should cause additional warming due to the albedo effect, which together with ENSO pattern changes and NAO shifts seem to explain a considerable degree of observed Arctic sea ice changes - unfortunately still with just the 33 years of history for reference.

When it comes to CO2, it is certainly a factor, as there is no question that more CO2 causes more radiation to be returned to the surface of the earth, but compared with the regional factors mentioned above, CO2 should be a truly global factor in the sense that it increases forcing around the world, and especially in arctic areas according to model predictions.

SH sea ice extent, however, has since 1979 shown a slight, but persistent increase, which is remarkable as ocean temperatures have increased as well.

This leaves me to conclude (granted a very simplistic conclusion) that regional weather pattern changes can last at least 30 years and can compete in effect with the increase in forcing caused by CO2.

The very low maximum of Arctic sea ice last winter seemed directly related to the strong NAO-, and this winter we had the opposite phenomena, which is causing Arctic sea ice to max out in the high end of what had been expected, especially with the significant packing of ice due to the west-Siberian high pressure five weeks ago.

If we get a period with predominantly negative ENSO conditions, and with some luck also NAO+ during NH winter, it would be interesting what that could do to restore Arctic sea ice - but that may be just wishful thinking..

Daniel Bailey

Fortunately, we have more than 33 years of history to go by (there still was a world before satellites). So conjectures and sweeping statements lacking support in the literature can be cheerfully examined in light of actual data. Per Kinnard et al 2011:

Reconstructed changes in Arctic sea ice over the past 1,450 years

"Arctic sea ice extent is now more than two million square kilometres less than it was in the late twentieth century, with important consequences for the climate, the ocean and traditional lifestyles in the Arctic. Although observations show a more or less continuous decline for the past four or five decades, there are few long-term records with which to assess natural sea ice variability. Until now, the question of whether or not current trends are potentially anomalous has therefore remained unanswerable.

Here we use a network of high-resolution terrestrial proxies from the circum-Arctic region to reconstruct past extents of summer sea ice, and show that—although extensive uncertainties remain, especially before the sixteenth century—both the duration and magnitude of the current decline in sea ice seem to be unprecedented for the past 1,450 years. Enhanced advection of warm Atlantic water to the Arctic seems to be the main factor driving the decline of sea ice extent on multidecadal timescales, and may result from nonlinear feedbacks between sea ice and the Atlantic meridional overturning circulation.

These results reinforce the assertion that sea ice is an active component of Arctic climate variability and that the recent decrease in summer Arctic sea ice is consistent with anthropogenically forced warming."

Further elucidation can be found here:

Kevin McKinney

Daniel Bailey--indeed, and there are other data showing the same thing. (For instance, the Chapman data on ice extent derived from historical shipboard observations.)

I note that it is a common denialist theme that glacier retreat has been occurring since the LIA--and it's probably one that is true as stated. (For instance, Google "northern hemisphere glacial retreat" and note how many denialist sites come up--one by the exceptionally foolish Joe D'Aleo was the top hit when I tried it.)

However, the retreat has hardly been uniform. The pattern of retreat observed suggests that the current retreat is not a forcing to climate change, but part of a feedback mechanism. See, for example:


Dr. Pelto comments here from time to time; perhaps he will weigh in on this question.


I hope John doesn't mind his questions being answered with questions, but I've found people tend to absorb better when they find their own information.

John: If they could have Winter Festivals on the Thames two hundred years ago...?
John, how common were these "Winter Festivals" (more commonly referred to as "Frost Fairs")? What factors (plural) caused the Thames to freeze over?
Clue: This question is brought to you by the word "hydrology" and the numbers 24 and 406.
In case there is a "so what" follow on - How would affect your position if it turned out the LIA was not as cold as you assume it to have been - would that increase your concern about recent warming or decrease it?

SH sea ice extent...?
What factors influence Antarctic sea ice extent differently to NH sea ice extent? (ie different factors and / or different influence).
Clue: This question is brought to you by the number 14 million.


Regarding the SH extent, fortunately there are more than 33 years of data there too.


Note the indices on the axis are transposed, should be 10^6 km^2.


John Christensen

To All; I am truly very pleased with the feedback, though some being more helpful than others.

I have no education in this area, and felt I was solidly in the AGW corner, until I read Al Gore's book. It seemed so superficial and biased in the statements and selected topics that I wanted to know more to get a better understanding of the world around us.

This is interesting to lots of people outside the scientific communities, because it does affect us all, and knowing where we came from can be a good learning in realizing where we need to go.

Last summer, while travelling to Houston, I took an extra flight to El Paso on my frequent flyer points and drove to the Guadalupe National Park to hike up the Permian Reef Trail, which was an extraordinary experience, watching the 250 mio year old reef overlooking the desert plains, and teeming with fossils of mostly extinct creatures.

The dilemma in this, of course, is that to truly enjoy and experience our nature, we tend to transport ourselves over great distances, and this extravagant behavior is what we may not be able to continue. But to what extent?

I am not a denier and enjoy all the articles on this blog and will research the links suggested above. Keep it going, I am not trying to fight your cause.


Daniel Bailey

John, there is a wealth of disinformation out there and few kernels of actual truth, outside of the science-based organizations and websites. Skeptical Science exists to help cut through the fog, to discern the wheat from the chaff by debunking the fake-skeptic memes from the science. Over 4,500 threads exist on all things related to climate science. All have links to the original, published & peer-reviewed sources they cite.

I would recommend starting with the Newcomers, Start Here and The Big Picture threads. This video is also an essential referent.

Daniel Bailey

Sorry, the one link I didn't check was the one that didn't work. Sigh.

John Christensen

@Neven, Sorry for having to ask, but since CT had a minimum of 2.9mio km2 in 2011, how could NASA have it as low as around 1.6mio km2?


The 1.6 mio are multi year sea ice, the rest of the ice would be first year sea ice.


Regarding Tiksi, in 1991 it had a "freakish" max. temperature of 34,3 °C. We could wonder what will happen this year. In any case, the record for the month May already has been broken.

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