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Eli Rabett

The other shocking thing is that the variability in Antarctic sea ice has really increased a lot from 1980.

Jim Hunt

Thanks very much for your many kind words Neven.

Firstly may I second your recommendation that anybody interested in the Arctic should take a good long look at the work of Jenny E. Ross.

Secondly I bring you yet more "Shock News" hot off the Great White Con virtual presses. Never before seen video footage of the USS Skate surfacing at an "ice free" North Pole in the summer of 1958!

Shock Historical News – Towing In at the North Pole in 1958!

Not only that, but also the forerunner of the forthcoming Great White Con Arctic Basin Big Wave (Fantasy?) Surfing Contest!

Have you ever imagined the likes of David Rose and Christopher Booker, clad only in polar bear suits, surfing the swell created by calving glaciers?

We have!

Shared Humanity

And I am certain this shocking increase in summer variability is directly related to AGW. Any ideas as to why this is happening?

William Smeltzer

"And I am certain this shocking increase in summer variability is directly related to AGW. Any ideas as to why this is happening?"

The second law of thermodynamics.


Jim, I did not know you were doing such very important work attempting to keep publishers publishing accurate and truthful information. "Thank you" for doing this and "Thank you" Neven for bringing this to my attention.

Jim Hunt

Thanks very much Vaughn. We need all the support we can get, since it is something of an uphill struggle!

The "official procedure" here in the UK involves attempting to negotiate a suitable "correction" directly with the offending newspaper. The publishers, of course, do their very best to ignore you. My evidence?

A Letter to the Editor of the Mail on Sunday


A Letter to the Editor of the Sunday Telegraph

Jim Hunt

There's even more "Shock News" this wet and windy Sunday morning over here in not so sunny South West England.

Christopher Booker ups the stakes in his attempt to rewrite the climate science history books:

The Greatest Scandal in the History of Science!

This time around the BBC is helpfully looking over his shoulder as his cards part company with his furry white chest.


Uh-oh, have to admit I got taken in by one of Jim's headlines. I'll try not to make that mistake again. Thanks for the tip, Neven. In any event, it was the Jakobshavn one, which did seem reasonably alarming, as you said. And Jim, thanks for your diligent work.

Jim Hunt

My pleasure ClimateHawk.

My most recent Bookerish headline is in fact deadly serious. The Jakobshavn one was reasonably serious also. Espen is the expert in these matters, and he says "I have been digging into my Landsat Archives, and I cant find evidence of any real calvings this early in the season"



"Does @DavidRoseUK only ever write fiction?"

I would have to say unequivocally, "Yes!"

Great job confronting these morons, Jim, although I am uncertain of your effect. Unfortunately everyone pays the price for the delay in confronting the problem of the disappearing ice.

Jim Hunt

Well Vaughn, one effect was to "persuade" both The Mail and The Telegraph to print "corrections" to their appalling Arctic sea ice coverage in the summer of 2013:


Unfortunately that didn't prevent the likes of Fox and Judy Curry repeating the nonsense across the rest of the Planet:


The UK's PCC was laboriously metamorphosing into IPSO in the summer of 2014, so we're still working on that one!



The news from Antarctica is just as shocking as the Arctic news but the situation has not been well explained. Deep convection has faltered in the Weddell sea and deep water formation around Antarctica has declined about 20%. Relatively warm water at about 300 m depth is rising up and melting the base of glaciers from below, creating a stable layer of freshened surface water around much of Antarctica. Thus there is more winter ice around Antarctica - Ice which reduced the heat loss to the atmosphere.

This situation is changing the global heat balance as more heat is stored in the oceans and more heat is transported north towards the Arctic.

-FishOutofWater- aka George

Jim Hunt

George - You may be interested in the new regional Antarctic area/extent graphs available at:


For the moment they are manually updated, and currently a little bit out of date. Take a look at the Indian and Pacific Ocean sectors though.

Back on the campaigning front, today we're idly wondering if there's any connection between Dana Rohrabacher and Christopher Booker:



Evening, George,
While Bostonians are probably digging out, over here we are experiencing the other side of winter's coin.
There are two ways to process data to have an indication of winter's strength. One is average temp. The other is about cold extremes. In the Netherlands a 'cold number' is produced through summing all daily average temps under zero dC. Climatology produces about 50 as a normal, though our erratic winters can get to 300.

Nowhere in the data is a two year pair of 'extremely mild winter' to be found. The call can be made after 31 March, but, as cold is not in sight for the next 14 days, it looks like that record will be booked.

The numbers: '13-'14 0.0 (! nada, not even one day on average) '14-'15: 7.8 (int.23 feb).

Andy Lee Robinson

Great article Neven, and Jim!

The Arctic/Antarctic minimum extents is actually quite shocking side-by-side. Such a stark contrast in behaviour.

As for Jakobshavn Isbræ calving, this isn't supposed to happen in February, as far as I can tell! One wonders what this melt season will bring.

Meanwhile, the Arctic Death Spiral hasn't changed much, despite the sea ice volume gains last year.

http://haveland.com/share/arctic-death-spiral.jpg (or lossloss .png)

(note this link always points to the latest version)


Why does your "shocking" sea ice graph end on year 2012? Why doesn't it show the data for 2013 and 2014? Cherry picking a little bit, are we?

Jenny E. Ross

Thanks very much, Neven and Jim! Greatly appreciated!

Jim Hunt

@Jenny - My pleasure!

@Cincinnatus - Because it does! Can you provide a link to a more recent one?

If you'd bothered to click some of the links above it would quickly become apparent to you that we're working on a bang up to date independent version. However that project is on hold, because Christopher Booker is promulgating surface temperature nonsense in The Telegraph yet again, and we've been denied any right of reply:


For an up to date Arctic only graph please feel free to go to:


and then scroll down slightly.

@Andy - If Jakobshavn Glacier is of particular interest to you, we've received some input from Professor Jason Box, of Dark Snow Project fame:


A cautious response: even if this calving were abnormal, we will likely see an advance in the next weeks that will fill the void. Why?

A) This glacier flows fast, and

B) Now with less flow resistance there will likely be an acceleration making the void filling happen even faster.

Cherry picking a little bit, are we?

A bit, but not intentionally, like you will see on a daily basis elsewhere. This was the best thing I could find, and I didn't have time to make a graph myself.

I'll look for or make an updated version. Do you expect to see anything there that renders my argument moot?


Cincinattus, all cherries have now been added at the end of the post.

Jim Hunt

@Neven - Snap, almost!

This is using NSIDC data rather than high resolution JAXA AMSR2, and the 2015 Antarctic minimum extent is of course still very much provisional:

Click the image for much more high res detail!


Well done, Neven, full data is so much less shocking than picked data.


If it weren't shocking, wouldn't paid disinformers have showed the full data, accompanied by the full explanations, instead of the neat trick they keep performing, fooling some of the people all of the time?

Jim Hunt

@Neven - This is the "explanation" we just received from The Telegraph for one of Booker's recent cherry picking articles:

A newspaper is not a scientific journal, and is not required to represent all the possible shades of evidence and interpretation that might have a bearing upon any given topic.

This is clearly an opinion article and identifiable as such. Against the background described above, readers can be expected to understand that any evidence offered is almost certainly contestable. It follows that in an opinion article of this nature only the most egregious inaccuracy could be significantly misleading.

They don't provide a scientific definition of "egregious inaccuracy".


I quite agree with what you say, Neven, although not with what you mean. Let me put it this way: if full data were always used, and thumbs kept off scales, then the gap between warmists and skeptics would be far less. I think we can agree on that.


Thumbs are not on the scales, Cincinnatus.

Scientists are continuously trying to *expand* the data they have available.

To imply otherwise is disingenuous.

Jim Hunt

@Cincinnatus - Here's a remarkably patient video by a real live climate scientist explaining how you yourself can determine who it is that has in actual fact got their "thumb on the scales":


Please feel free to do your own due diligence and report back here with your findings.



Cincinnatus is just taking a break from correcting the deluge of errors on WUWT site.

I dont think that Neven's original presentation had anything wrong, as he published 2013-14 data numerous times
before. 2013-14 melt seasons were more complex to understand
therefore impossible to explain to dimwitted deniers.


I agree there are many errors on WUWT, especially from the commenters, and I do in fact correct some of them occasionally (under a different pseudonym). But here too. What was that final line from Romeo and Juliet again? Oh yes, "All are punished".


Well, if Arctic sea ice loss continues unabated, there's a risk indeed that all will be punished.


The focus article in the March 2015 National Geographic is: "The War on Science." There are 5 sections and one of these sections discusses the premise: "Climate Change Does Not Exist."

Part of the discussion centers around how and why incorrect information gets imbedded into peoples' beliefs. There are a number of reasons such as religious beliefs, well publicized studies which are later proven false, to just believing something incorrect because someone that person believes in says it, etc.

My point is, if anyone is interested, this article gave me a much better understanding of why many people do not believe science and possibly some insights into how to deal with this group before as Neven says, there's a risk indeed that all will be punished."

Jim Hunt

@Vaughn - Don't forget the work of Larry Hamilton. We haven't!


Education and science knowledge matter too, but the effects of education and knowledge vary with political beliefs. Among liberal and moderate respondents, for example, expressed concern about polar change increases with education. Among the most conservative respondents, however, concern decreases with education.

Re the Nat Geo article you mention, see:


L. Hamilton

Here is my bar-graph version of the N and S minimum sea ice area, 1979 through 2014. Feel free to borrow:


L. Hamilton

Jim, I did say I'd write something new. In the meantime there's another installment of "Polar Polling" that bridges the General Social Survey (2006, 2010) and a more recent survey question about sea ice,

Jim Hunt

Thanks very much Larry, and I didn't actually mean that remark the way you seem to have taken it!

FYI - Our latest guest post, hot off the GWC virtual presses:

The Telegraph is Wrong Again on Temperature Adjustments

L. Hamilton

Intentionally or not it reminded me I'd said OK, and ought to follow through on such things. Send me an email if you want to chat offline.

Jim Hunt

An email is "in the post" Larry. Thanks again.


Plotted above of course (with nice star field), but it's perhaps worth remembering what late summer Antarctic sea ice actually looks like (from ClimateReanalyzer.org):


That is that there's hardly any ice at all except in the lee of the Peninsular. The source of the variability is pretty obvious, and the likely source of the increase in variability is not hard to glean.

Jim Hunt

This is not really "Shock News", as Neven explains at the top. Nonetheless after a brief hiatus both the NSIDC and IJIS Arctic sea ice extent metrics are once again at the lowest value for the date since their respective records began.

Yesterday's IJIS came in this morning at 13,827,443 km2. We'll have to wait a few hours more for the NSIDC number.

Kevin McKinney

A bit OT, but there's some pretty stunning Arctic and Antarctic photography here:


(Also, a profile of a pretty interesting photographer.)

Kevin McKinney

Larry, I've used your SIV bar graph, here:


(It's the third in a series of 4 articles on some of climate change's 'epistemological basics', as I like to say.)

I'd love to update it to reflect 2014 numbers, if you've done that update.

L. Hamilton

Happy to oblige Kevin. You (or anyone else) can borrow the sea ice minimum volume (through 2014) graph here:

In a similar vein here is Arctic and Antarctic minimum area:

And Arctic extent:

L. Hamilton

Earlier this year a survey-based paper, "What people know," was published in a special Arctic change issue of Journal of Environmental Studies and Sciences. An author's draft of the paper can be downloaded here:

The individual graphics, showing what the public believes about trends in Arctic sea ice area, can be found at these links:





Bill Fothergill

Hi Jim,

As you will doubtless have seen before me, IJIS went down another 29 thousand sq kms on the 2nd March, so that's 4 days in a row in lowest position. This cherry-picking malarkey is a lot of fun, ain't it?

By the way, do you think we'll ever get any meaningful answers from "ryland" over on SkS?

cheers btf

Chris Reynolds

Good post Neven.


Had you bothered to check the data yourself you could have avoided making yourself look foolish.

Jim Hunt

Bill - Re your final question, it seems unlikely at the moment. Reading your latest addition to that SkS thread reminds me that we really should endeavour to get together around a jar of scrumpy at some point soon!

Is there any chance you might be attending the forthcoming Greener Teign meeting with some local prospective parliamentary candidates?


There are a few of us down yer who are not "deeply conservative in their political opinions"!

Andy Lee Robinson

Too early to call maximum extent, but can't help wondering.
The anomaly is quite remarkable.

Kevin McKinney

Thank you, Larry! Much appreciated.

David Sanger

Down almost 60K again, now 201K below previous low for the day (13,939,904 in 2011)


All that wonderful thick ice that was developing during the last two years? I think this just shows how poor that thick ice is and if the MYI is that bad the rest must be worse. If we get a return to a 2007 or 2012 summer IMO there is not enough good ice left to fight what could be done to the ASI. Not saying it will all go, but we could end up with mainly what is called grey ice.


A review of the IR imagery reveals the much of the Arctic sea ice in the Beaufort or Chukchi has been fractured or rubble all winter. The ESAS and Laptev have had similar conditions.

I have been calling the Beaufort Gyre, the "Beaufort Blender" this season, given its continual refracturing. Areas south of Banks Island never froze solid this winter, south of Baffin Island has been "rubble."

North of Svalbard fracturing has run close to 90 N many times.

The Arctic Ocean fracturing has often sent plumes of warmer air over the ice till refreeze, which is an indicator of the warmer sea temps under the ice.


For the person who wanted a more recent chart of minimum extent, I usually do one each year.


From here:

Or a less colourful version of same:



Oops, I see you've already added it, Neven. And unlike mine, your y axis scaling was down to zero, which some people insist upon :)


Is there a new link for the IJIS data?

Oops, I see you've already added it, Neven. And unlike mine, your y axis scaling was down to zero, which some people insist upon :)

Ah, I should've remembered your graph, Sou. And save myself the trouble. And let your graphs run at least to 1 million km2, because below that is when we call the Arctic ice-free for all practical purposes.

Ecojosh, the data file is here:


Climate Changes

Climate Change by Numbers on BBC4 explained nicely the maths behind Climate Change. Mainly aimed to those who still argue that temperatures are fiddled, etc...

Bill Fothergill

Re: "Climate Change by Numbers" on BBC4

I have watched that programme once (thus far), and thought it missed a golden opportunity to use the maths in order to debunk some of the bollocks that constantly gets regurgitated in denier circles.

I've got it on hard disk and will view it again - as soon as I hook up the HDD to the goggle box.

Nonetheless, it was the kind of thing that must help in the laudable endeavour of trying to explain a seriously complex subject to an audience that, generally speaking, is going to struggle to follow the complexities.

The programme did use an interesting hook right at the beginning (where else?) by putting up 3 numbers...


I'll bet that's got some of you intrigued!

Definitely worth a look

cheers bill f

David Sanger

new JAXA sea ice page is here


@ bill f: Many thanks, caught it on youtube.[url=http://youtu.be/3zqkPmM_hj4]Climate Change by Numbers BBC Documentary 2015[/url]
I can understand their approach. Instead of tackling bad science head on, they came at it from a similar angle as many deniers use and that is math with math. Clearly stating that in those 3 numbers 3 very different types of math are used and all of them are recognized and work. Also by explaining the math by using very non climate change examples, very hard to refute.


Not sure what I did wrong on code.

Bill Fothergill

The number "1 trillion" referred to above by some idiot (oh, it was me) relates to the cumulative tonnage of carbon we have to avoid utilizing in fossil fuel burning, cement production or land usage changes in order to avoid a dangerously high (>2 deg C?) temperature rise.

Many, if not most, readers on this site will be comfortable with the technique for converting a given mass of carbon into its eventual impact on concentration levels of atmospheric carbon dioxide. However, those who are a bit shaky on this might care to read on...

One, of many, possible starting points is to consider what we mean by atmospheric pressure: the "standard" atmospheric pressure is usually quoted as 1013.25 hectopascals* or hPa. So what the hell does that actually mean?
(*The spell checker flagged the term "hectopascals", and helpfully offered "pectorals" as a replacement. I think it was trying to make me look even more of a tit than usual!)

Those of us old enough to have worked in multiple measurement systems should appreciate the simplicity of working entirely in SI units. The SI unit of pressure is the pascal, and atmospheric pressure is usually referred to in hectopascals. The reason is historic: one hPa being effectively identical to the more familiar millibar.

As pressure is defined as force per unit area, standard atmospheric pressure could also be described as equal to 101,325 newtons per sq metre. Newton's Second Law states that force is equivalent to mass times acceleration, and gravitational acceleration at the Earth's surface is about 9.81 metres/second squared.

Dividing 101,325 by 9.81 gives a numeric value of about 10,329 and the units are now in kilograms/sq metre - alternatively 10.33 tonnes/sq metre. This means that there are almost 10 and a third tonnes of air floating above every sq metre of the Earth's surface.
(So any time you are feeling depressed, you now know that you've got a bloody good reason.)

The total mass of the atmosphere can now easily be found by simply multiplying this figure (10.33 tonnes/sq metre) by the surface area of the planet. As the mean planetary radius is somewhere around 6,374 kilometres, and the area is given by 4 pi times the radius squared, the Earth's surface area is about 511 million sq kilometres.

Multiplying out means that the mass of the atmosphere is about 5.27 million, billion tonnes. (5.27 x 10 ^18 kilograms)

When talking about CO2 levels, atmospheric composition is usually quoted in parts per million by volume, or ppm(v). Each molecule (at a given pressure level) effectively occupies the same volume as any other (at the same pressure). There is an important distinction to understand: at this point, any difference in the relative atomic masses of two differing molecules does not affect the quoted concentration ratios.

However, that is about to change. As any standard text will show, Nitrogen constitutes about 78% of the atmosphere and Oxygen about 21%. As both gases are basically diatomic (ie consisting of two atoms in their most common configuration) and their atomic weights are 14 and 16 respectively, the "mean" atomic weight of an "average" molecule in the atmosphere is very close to 29 Atomic Mass Units (AMU).

Carbon exists in two stable (non-radioactive) isotopic forms Carbon 12 and Carbon 13. As the C13 concentration is is only about 1.1%*, the atomic weight of a carbon atom is very close to 12, and hence the atomic weight of a carbon dioxide molecule is 44 AMU (ie 12 + 16 + 16)
(* The C13 ratio is depleted in materials, such as fossil fuels, that have a biogenic source. Basically, plants preferentially take up the C12 form of carbon. This asymmetry is a real smoking gun in any attribution study.)

Since the atmospheric mass is about 5.27 million, billion tonnes, any gas with a concentration ratio of 1ppm(v), and possessed of a molecular mass similar to the atmospheric average of 29 AMU, would therefore have a mass of about 5.27 billion tonnes.

As the molecular weight of carbon dioxide is instead 44 AMU, one ppm(v) equates instead to 5.27 * (44/29) or 8 billion tonnes (or 8 gigatonnes). Confusingly perhaps, more often than not it is the mass of Carbon that gets discussed. As this constitutes only 12/44 of the carbon dioxide mass, each extra ppm(v) of carbon dioxide equates to the carbon burden in the atmosphere going up by approximately 2.18 gigatonnes*.
(* Or, according to the spell checker, 2.18 gallstones.)

Matters are confused further by the fact that by no means all carbon dioxide remains resident in the atmosphere. Studies on the carbon cycle suggest that only 45% stays in the atmosphere, with the remainder going into oceanic or land based carbon sinks.

See this NASA link for a carbon cycle overview...

Given that 55% of the emitted carbon dioxide is (currently) being taken up by carbon sinks, a 1ppm(v) rise in atmospheric carbon dioxide levels equates to 2.18/0.45 or about 4.85 gigatonnes of carbon usage.

As the values assigned to carbon cycle fluxes come with a big health warning, the precision of this number is highly questionable, and it's more sensible simply to say that, at present, every 5 gigatonnes of carbon burned pushes atmospheric CO2 up by approximately another 1ppm(v).

If one looks at the http://trillionthtonne.org/ website, there is a nifty counter showing where we are on the current headlong trajectory towards burning up that magic trillionth tonne.

best wishes all - and Neven, sorry for taking up so much space

cheers bill f


Many thanks Bill F for very informative capitulation.
2 things that are generally missed by most not understanding feedbacks, is that that 1 trillion also includes anything nature wants to add to it via things like permafrost melt. The other elephant in the room is that 2C is seen as a figure where natures status quo can be kept and controlled by humans.
IMO I think all the horses already have left the barn and so far out of sight you will never find them to get them back.
I am starting to think that speed of change has a great multiplier effect. Adding 200 ppm over 10,000 yrs and increasing temps by 2C nature can adjust to with only minor changes over all. We are trying to see what happens when you try it out over 200 years.
Could we compare it to the difference of what would happen to car occupants between going from 0-120 km/h in 5 seconds and 0-120 km/h 0.1 seconds. Even if you manage to end at the same speed. the speed you get to it has 2 different outcomes to the passengers.
I think that even if we were to stop below 1 terra tonne, the acceleration has been so great on all parts of the ecco system when it finally gets to the plateau of its new status quo 2C will be a long gone memory as will most of the ice.

Seke Rob

Still melting away [The Antarctic too], at an accelerated rate... http://www.bbc.com/news/science-environment-31965454

Kevin McKinney

"Still melting away…"

Yes, not a cheerful study. There've been a couple lately.


Also a tidbit from Weather Underground weather historian, Christopher C. Burt:

"Possible New Continental Heat Record for Antarctica"


Artful Dodger

Welcome back, Seke Rob. Looking forward to more of your excellent charts and graphs. Saluti!


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