Tag Archives: NSIDC

The United States’ National Snow and Ice Data Center

Has Arctic Sea Ice Already Started to Recover?

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In a word, NO!! Here we go again.

Them:

According to David Rose’s headline in yesterday’s Mail on Sunday:

Global warming ‘pause’ may last for 20 more years and Arctic sea ice has already started to recover.

There is of course plenty more where that came from, such as:

The 17-year pause in global warming is likely to last into the 2030s and the Arctic sea ice has already started to recover, according to new research.

A paper in the peer-reviewed journal Climate Dynamics – by Professor Judith Curry of the Georgia Institute of Technology and Dr Marcia Wyatt – amounts to a stunning challenge to climate science orthodoxy.

Not only does it explain the unexpected pause, it suggests that the scientific majority – whose views are represented by the UN Intergovernmental Panel on Climate Change (IPCC) – have underestimated the role of natural cycles and exaggerated that of greenhouse gases.

along with a:

Graph that makes a mockery of warming

Us:

If you take a look at the evidence from the NSIDC the Mail on Sunday recently provided us with in support of their previous inaccurate headlines you will discover it says:

Monthly August ice extent for 1979 to 2013 shows a decline of 10.6% per decade.

QED? Apparently not as far as the Mail on Sunday’s concerned. If further evidence is needed please read our previously published “stunning challenge” to Judith Curry’s Arctic sea ice expertise. In brief:

Judith Curry republishes the same nonsense [as The Mail], but then neglects to publish even a similarly mealy mouthed “correction”, let alone anything remotely resembling the information originally published by the NSIDC upon which this collective fantasy is allegedly based. Therefore Judith should be taken seriously, and as a climate scientist rather than a tabloid journalist or a fantasy fiction writer?

We think not.

Them:

David Rose goes on to say (amongst other things) that:

The graph shown above, based on a version published by Dr Ed Hawkins of Reading University on his blog, Climate Lab Book, reveals that actual temperatures are now below the predictions made by almost all the 138 models on which the IPCC relies.

The pause means there has been no statistically significant increase in world average surface temperatures since the beginning of 1997, despite the models’ projection of a steeply rising trend.

Us:

On Dr. Hawkins’ blog, commenting on a previous David Rose article in the Mail on Sunday, he says this:

David Rose has written an article in the Mail on Sunday which, by eye, seems to use the top left panel from the figure below, but without mention of its original source. In the article David Rose suggests that this figure proves that the forecasts are wrong. This is incorrect.

Here’s the figure Dr. Hawkins is referring to:

Ed Hawkins original graphs comparing CMIP5 simulations with observations
Ed Hawkins’ original graphs comparing CMIP5 simulations with observations

Finally, for the moment at least, here’s the text of an email we sent to the Managing Editor of the Mail on Sunday this morning:

Hello John,

Thanks for your additional comments. Unfortunately you still fail to address the primary question I’ve been asking for almost 2 months now, so I will be formally pursuing matters concerning the September 8th article via the PCC from now on.

Moving on I note that you have published another article by David Rose this weekend entitled “Global warming ‘pause’ may last for 20 more years and Arctic sea ice has already started to recover”, which mentions both Judith Curry and Arctic sea ice once again. I already have a few bones to pick with you about this one as well.

1. I posted an online comment on the article yesterday evening. It remains invisible this morning. Your web site says “The comments below have not been moderated.”. My comment included no links, although it did mention the “Great White Con”. Perhaps you could look into that for me, and provide me with an explanation?

2. Do you suppose it would be possible to persuade David to reveal his sources any more swiftly this time around? Where does his misleading graphic entitled “Graph that makes a mockery of warming” and the underlying data come from? At first sight it doesn’t seem to be from Judith Curry’s “Stadium wave” paper for example.

We have yet to receive a reply.

The Mail’s Concentration on Sea Ice Extent

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Further to our previous communications about what we refer to here as “The Great White Con” I have now received another email from John Wellington, Managing Editor of the Mail on Sunday.

Them:

Amongst other things it says that:

The incorrect figure published by the NSIDC was taken in good faith. Our writer [AKA David Rose] did not expect an institution of its stature to make such an error, so it is not reasonable to expect him to contact NSIDC to check it, specially as the general idea of an increase in the icepack was consistent with more anecdotal information such as the shipping information. You say we did not produce evidence of the NSIDC mistake. I am attaching a screen grab of their web site before they corrected it.

Mail on Sunday screen grab of NSIDC article entitled "A real hole near the pole"
Mail on Sunday screen grab of NSIDC article entitled “A real hole near the pole”

John’s latest email also included the following statement:

The August NSIDC report begins with a diagram (see  attachment). This shows the Arctic ice sheet stretching from Siberia to the Canadian islands:

Another Mail on Sunday screen grab of NSIDC "Arctic Sea Ice News" article of September 4th 2013
Another Mail on Sunday screen grab of NSIDC “Arctic Sea Ice News” article of September 4th 2013

Us:

You will note I have taken the liberty of annotating The Mail’s screen grabs with what seem to me to be reasonable questions for any vaguely competent investigative journalist to ask themselves when reading the NSIDC’s early September update. At this juncture I can only repeat this question from my most recent missive to The Mail:

This raises any number of questions about the Mail on Sunday misleading its readers, such as “Why didn’t The Mail ask the NSIDC about the apparently conflicting information, much like Bob Ward did, before publishing an article relying on that information?” not to mention “Why can’t David Rose perform accurate arithmetic?”

and provide my own screenshot from the “terminology” page of the NSIDC web site in a no doubt vain attempt to provide John and David with an answer to just one of those questions:

NSIDC explanation of the terms "concentration" and "extent"
NSIDC explanation of the terms “concentration” and “extent”

In brief:

Extent defines a region as either “ice-covered” or “not ice-covered.” For each data cell, it is a binary term; either the cell has ice (usually a value of “1”) or the cell has no ice (usually a value of “0”).

 Do you suppose that given their apparent difficulties in performing elementary arithmetic John and David are able to appreciate the difference between “1 or 0” and “low-concentration sea ice (20 to 80% cover) within our extent outline” or even “near-zero ice concentration“?

How about the readers of The Mail on Sunday, or the Press Complaints Commission for that matter?

The Balding Arctic Exposed

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I’ve recently received a letter signed by John Wellington who is the Managing Editor of The Mail on Sunday.

Them:

Referring to David Rose’s Mail on Sunday article of September 8th 2013 John says amongst many other things that:

We deny that the article was significantly inaccurate apart from the original headline figure which we have already corrected.

and:

In August, ice did stretch from part of the Siberian shore to the Canadian islands. The image published in the newspaper and online supports this statement as does the enclosed image from the NSIDC site which shows the ice extent on August 18.

Here’s that image, which comes from the August 19th 2013 edition of the National Snow and Ice Data Center’s “Arctic Sea Ice News” entitled “The balding Arctic“:

National Snow and Ice Data Center graphic showing Arctic sea ice extent on August 18th 2013
NSIDC graphic showing Arctic sea ice extent on August 18th 2013

Us:

I’m currently writing a reply to John’s letter. Amongst many other things it directs his attention to this very article and says:

Images showing sea ice “extent” reveal remarkably little about whether an “ice sheet” is “unbroken” or not. If that is what you want to illustrate then an image showing “concentration” is much more helpful. In their report of September 4th upon which David Rose’s article is supposedly based, at least in part, the NSIDC helpfully provided such an image. The Mail on Sunday didn’t publish that image, or a similar image from 2012. In order to correct this inaccuracy they should do so.

Since they’ve evidently read the NSIDC’s news that the Arctic was “Balding” towards the end of August and there was “A real hole near the pole” by early September John and David should be aware of this already, but it seems a refresher course is necessary. On August 19th the NSIDC pointed out that:

Satellite data from the AMSR-2 instrument and MODIS show an unusually large expanse of low-concentration sea ice (20 to 80% cover) within our extent outline (15% or greater, using the SSM/I sensor) spanning much of the Russian side of the Arctic and extending to within a few degrees of the North Pole.

While some of the low concentrations recorded by AMSR-2 may be due to surface melt on sea ice, the MODIS image confirms that a large region is covered by isolated floes.

On September 4th the NSIDC also helpfully pointed out that:

A large hole (roughly 150 square kilometers or 58 square miles) of near-zero ice concentration appears to have opened up at about 87 degrees North latitude.

Here is a “true-color” image from September 4th 2013 using MODIS bands 1, 4 and 3, helpfully made available by NASA to anyone who might be interested via the EOSDIS Worldview web site:

NASA Worldview “true-color” image of the North Pole area on September 4th 2013 derived from bands 1,4 and 3 of the MODIS sensor on the Terra satellite
NASA Worldview “true-color” image of the North Pole area on September 4th 2013 derived from bands 1, 4 and 3 of the MODIS sensor on the Terra satellite

The lines in this image converge on the North Pole, the same location as the little cross in the NSIDC extent image near the top of this article. Let’s play “Spot the Difference” yet again shall we. Would you say that the sea ice underneath the clouds looks “broken” in this Worldview “true-color” image? How about in the the University of Bremen concentration images often shown by the NSIDC, or in the NSIDC “extent” image above, or in the NASA “extent” videos so beloved by David Rose and the Mail on Sunday?

The David and Judy Show

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In case today’s headline metaphor doesn’t readily translate into other cultures, it refers to the popular fairground sideshow in which a couple of puppets dance on the end of some strings, accompanied from time to time by a baby, some sausages, a crocodile and a police officer.

Us:

The Great White Con was recently mentioned on the Arctic Sea Ice Blog, where the discussion turned to news of a recently published academic journal article by Marcia Glaze Wyatt and Judith A. Curry entitled “Role for Eurasian Arctic shelf sea ice in a secularly varying hemispheric climate signal during the 20th century”.

In one response it was suggested that:

I always think it’s terribly sad when a study is immediately condemned on the basis of not whether it has been peer reviewed, or methodology, or objectiveness, but on the basis of who wrote it. It’s the classic open goal displayed by supporters of the consensus (which includes myself) to anything which may challenge entrenched beliefs.

Them:

In partial answer to that point, here’s a screenshot from an article entitled “Arctic sea ice minimum?” on Judith Curry’s personal blog this morning:

An extract from Judith Curry's blog article "Arctic sea ice minimum?" on October 13th 2013
An extract from Judith Curry’s blog article “Arctic sea ice minimum?” on October 13th 2013

Us:

From the other side of the fence here’s a couple of screenshots from the September 4th edition of the NSIDC’s Arctic Sea Ice News entitled “A Real Hole Near the North Pole“:

NSIDC Arctic Sea Ice News report for August 2012
NSIDC Arctic Sea Ice News report for August 2012

The NSIDC discuss "Water Near the Pole" on September 4th 2013
The NSIDC discuss “Water Near the Pole” on September 4th 2013

Would anyone care to play “Spot the difference” with me? If the differences between the official National Snow and Ice Data Center version of recent events in the Arctic and David and Judy’s version aren’t immediately obvious to you there are plenty of clues sprinkled throughout the rest of this web site to help. Does any of that help to explain my comment on the Arctic Sea Ice Blog to the effect that:

If [Judith Curry] can’t even get the basics right I fail to see why anyone (apart from David Rose of course) should place any credence whatsoever in her “Stadium Waves”, although I must admit I haven’t read the paper yet. I fear it will be a while before it rises to the top of my “to do” list.

Russia’s Northern Shores

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Regular readers will have realised by now that we’ve been pestering the Mail and The Telegraph with telephone calls and emails for weeks now. That’s because, as The Economist put it last weekend:

There are climate facts—and facts are stubborn things.

Both The Mail and The Telegraph have now corrected a couple of the gross inaccuracies they printed (virtually and/or physically) on September 8th, but many more remain. One of those is the identical phrase in both articles saying:

An unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shores.

The fact of the matter is that this statement is untrue. I’ve recently received a couple of letters about this from “The Daily Telegraph” signed by “Robert Winnett, Head of News”. Here’s an extract from the first one:

Them:

Reputable evidence exists to show an unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shore.  This can be seen on the National Snow and Ice Data Center’s website [in the article] “A Real Hole Near the North Pole“.  The site states that the average ice extent for August 2013 was 6.09 million square kilometres, which is more than half the size of Europe.

Us:

Have I got news for you Robert!  If you’d read any of the articles on here, or watched any of the videos I linked to in my emails, that wasn’t the “fact” I was quibbling about. The fact is that the Arctic “ice sheet” was not “unbroken” and did not “stretch… to Russia’s northern shore” on September 8th 2013 and for considerable periods of time both before and after that date. Here’s an extract from The Telegraph’s second letter:

Them:

In reply to your enquiry, the Telegraph’s policy is to correct clear inaccuracies once we are alerted to them – and in appropriate cases update articles on our website.

Us:

I thought I’d already made this perfectly plain, but evidently not, so here’s yet another alert about clear inaccuracies in the “reporting” of climate science in The Telegraph:

Will The Telegraph Print the Truth in the Cold Light of Day?

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I just received an emailed letter from the Telegraph’s Head of News, part of which reads as follows:

The Telegraph has looked into the matters you raise. As far as the points concerning ice extent are concerned, the incorrect information was derived from data published by the National Snow and Ice Data Center (NSIDC). The mistaken information was due to a typographical error, which the NSIDC only corrected after the article that incorporated it was published. We have since updated the online versions of the article and explained why this was necessary.

There is no mention in the letter of any “updates” or “corrections” being put into print. The Telegraph are thus telling much the same story as the Mail, which is of course wholly unsatisfactory when it comes to correcting the long list of “inaccuracies and misrepresentations” they have recently published regarding the sorry state of sea ice in the Arctic. This is how they’ve done it:

Them:

Hayley Dixon’s article entitled “Global warming? No, actually we’re cooling, claim scientists” from September 8th now starts as follows:

There has been a 29 per cent increase in the amount of ocean covered with ice compared to this time last year, the equivalent of 533,000 square miles.

In a rebound from 2012’s record low, an unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shores, days before the annual re-freeze is even set to begin.

The Northwest Passage from the Atlantic to the Pacific had remained blocked by pack-ice all year, forcing some ships to change their routes.

One ship has now managed to pass through, completing its journey on September 27.

with the following additional “explanation” at the end:

Update: As at the date the article was first posted it relied on information about ice extent from the Nasa-funded National Snow and Ice Data Centre (NSIDC). This information contained a typographical error which the NSIDC subsequently corrected. The article has been amended in line with the correct information.

In addition, we have amended our reference to the Northwest Passage following the successful traverse, completed on September 27 after our article was published, of the Danish bulk carrier Nordic Orion.

Us:

Should The Telegraph’s Head of News be interested in some slightly stale Northwest Passage news, here’s a picture published on econnexus.org on September 4th in an article linked to below, which takes a close look at the “pack ice” supposedly “blocking the North West Passage” on that date:

Sea ice concentration in the Northwest Passage on September 4th 2013, according to AMSR2
Sea ice concentration in the Northwest Passage on September 4th 2013, according to AMSR2

Them:

Geoffrey Lean’s article entitled “Global warming: Will the truth brave the cold light of day?” from September 13th now carries the following “explanation” at the bottom:

Update: After this article was published, a bulk carrier – the MV Nordic Orion – was able to pass through the Northwest Passage on its way from Vancouver to Finland.

Christopher Booker’s article entitled “The ice is not melting, yet still the scaremongers blunder on” from September 21st appears to be completely unmodified.

Us:

Here’s some extracts from my own (repeated) email to The Telegraph, to which they have also failed to respond satisfactorily (in my humble opinion!):

a) “An unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shores,”

Inaccurate – See: https://greatWhiteCon.info/2013/09/an-unbroken-ice-sheet/ for plenty of visual evidence of that.

b) “The Northwest Passage from the Atlantic to the Pacific has remained blocked by pack-ice all year, forcing some ships to change their routes.”

Inaccurate – See: http://econnexus.org/the-northwest-passage-in-2013/

c) “That has been enough to make a mockery of a much-publicised prediction, six years ago, by Prof Wieslaw Maslowski, of the Naval Postgraduate School in Monterey, California, that the Arctic would be entirely ice-free by 2013”

Inaccurate – See (and hear) https://greatWhiteCon.info/2013/09/shock-news-why-isnt-the-arctic-ice-free/ for visual and aural evidence of that.

d) “The ice is not melting, yet still the scaremongers blunder on”

Inaccurate – The ice is melting. See Geoffrey Lean’s article!

I can see that this particular story is going to run and run!

Santa’s Secret Summer Swim

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This weekend the Mail on Sunday admitted that the headline numbers in David Rose’s  “And now it’s global COOLING!” article published on September 8th were inflated by a factor of approximately two. This is how they explained that discrepancy to their faithful readers:

Scan of the bottom of page 31 in the September 29th 2013 edition of the Mail on Sunday
The bottom of page 31 in the September 29th 2013 edition of the Mail on Sunday

Can you spot the MILLION square km blunder by the Mail on Sunday? For the benefit of the scientifically illiterate amongst you I’ll explain, as I did yesterday in an email to the Mail on Sunday’s Managing Editor:

It appears that whoever writes your headlines is unaware of the difference between “A MILLION km” and “a million square km”. The former is a distance, and hence has no area. The latter IS an area.

Them:

As you can clearly see, the Mail reported yesterday that:

On September 4, NSIDC, based at the University of Colorado, stated on its website that in August 2013 the Arctic ice cover recovered by a record 2.38 million sq km – 919,000 sq miles – from its 2012 low.

News of this figure was widely reported – including by MailOnline – on September 8.

Us:

The headline of the report published on the NSIDC website on September 4th reads as follows:

A real hole near the pole

The related text reads as follows:

A large hole (roughly 150 square kilometers or 58 square miles) of near-zero ice concentration appears to have opened up at about 87 degrees North latitude. Small areas of open water are common within the ice pack, even at the North Pole, as the ice pack shifts in response to winds and currents, resulting in cracks (called leads) in the ice. The current opening seen in our satellite imagery is much larger.

and the relevant area of the accompanying satellite imagery looks like this:

University of Bremen colour visualisation of Arctic sea ice concentration for September 2nd 2013
University of Bremen AMSR2 colour visualisation of Arctic sea ice concentration for September 2nd 2013

Them:

Since the Mail’s intrepid reporter evidently read those words and looked at that picture, why on Earth do you suppose that the Mail on Sunday printed these words four days later?

Days before the annual autumn re-freeze is due to begin, an unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shores.

Even more to the point, why on Earth do you suppose that the Mail on Sunday left those words unaltered following their September 28th edit of the online version of that article?

Us:

Here’s our latest video update on the 2013 Arctic sea ice refreeze. The “Polar Polynya” is prominent by its presence, as is the broad band of open water between the “broken ice sheet” and “Russia’s northern shores”:

The “Polar Polynya” Reappears!

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Whatever David Rose may say in the Mail on Sunday, satellite images from high above the Arctic make it abundantly clear that there is in fact no “unbroken ice sheet [that] already stretches from the Canadian islands to Russia’s northern shores.”

Should further confirmation of that fact be needed, here’s our latest video analysis of the Arctic “refreeze” thus far:

The Great White Con – Update 1 from Jim L. Hunt on Vimeo.

As our video update points out, if you look carefully at the Arctic sea ice concentration maps derived from AMSR2 data, the large “Polar Polynya” visible is the region of the North Pole earlier this month seemed to be shrinking to nothing following the (provisional) NSIDC 2013 extent minimum on September 13th. However it now seems to have been given a new lease of life, as has the nearby “Barents Bite” of open water north of 85 degrees latitude.

That area of the Arctic is currently obscured by cloud, but here’s an image captured by the Aqua satellite earlier today of the “broken ice sheet” off “Russia’s northern shores”:

The Arctic sea ice edge off "Russia’s northern shores" from the Aqua satellite
The Arctic sea ice edge off “Russia’s northern shores” (Click for larger version)

Image courtesy of NASA Worldview from from the Aqua satellite.

Can you by any chance spot any cracks and/or holes in the supposedly “unbroken ice sheet”? Can you spot “Russia’s northern shores” for that matter?

In conclusion, for the moment at least, please note that we are now collecting all these periodical updates together in one handy location.

An Unbroken Ice Sheet?

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David Rose has now had another article published in the Mail on Sunday. The new one refers back to his previous words of wisdom about the Arctic, imparting this piece of information:

The Mail on Sunday’s report last week that Arctic ice has had a massive rebound this year from its 2012 record low was followed up around the world – and recorded 174,200 Facebook ‘shares’, by some distance a record for an article on the MailOnline website.

That’s a lot of people repeating a load of old nonsense! Here at GreatWhiteCon.info we also have a Facebook presence, so if you would like to share our alternative interpretation of what’s really going on in the Arctic please take a good look at:

https://www.facebook.com/GreatWhiteCon

and share that information with your friends, as long as it makes more sense to you than David Rose’s record breaking article.  Meanwhile here in at Great Ivory Towers we’ve still only progressed as far as the third sentence in David’s article the weekend before last, which reads as follows:

Them:

Days before the annual autumn re-freeze is due to begin, an unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shores.

As you’ll discover below we’ve been experimenting with YouTube recently, where we stumbled upon a NASA video which led us to a page on NASA’s Goddard Space Flight Center web site where you can download a high resolution version of the same video. We did that, and then much like the Mail, we took a screenshot from the video to reveal an image remarkably like the one they published just over a week ago. Here it is:

NASA visualization of the Arctic on August 15th 2013
NASA visualization of the Arctic on August 15th 2013

Us:

We also found that NASA’s Scientific Visualization Center had another similar video available for download, covering the period from August 1st to September 13th 2012. Here’s a screenshot we took from that video, for August 15th 2012:

NASA visualization of the Arctic on August 15th 2012
NASA visualization of the Arctic on August 15th 2012

For some reason a similar image cannot however be found in David Rose’s Mail on Sunday article of September 8th 2013. Instead that contains an image labelled “August 27th 2012”. Whilst you ponder why the Mail was avoiding comparing like with like visually 9 days ago, here’s a little animation we’ve put together using alternative visualizations of Arctic sea ice, this time of ice concentration and generated by the University of Bremen. It shows how the sea ice cover has been changing from August 15th through to September 13th 2013, which may ultimately prove to be day of  the minimum extent  in 2013, using the NSIDC’s methodology at least. Note that it lingers for a while on August 27th, and we hope you like the sound track!

Verdict:

For reasons known only to themselves the Mail certainly weren’t comparing like with like  visually on September 8th 2013. They evidently weren’t comparing like with like numerically either, since however hard we try comparing numbers from “the same time last year” we can’t come up with the Mail’s magic “60% increase”. Comparing NSIDC extent for  August 15th 2013 with August 27th 2012 did however lead us to perform this bit of elementary arithmetic:

6.16 / 3.94 = 1.56 – A 56% increase.

However hard we try we still can’t get close to the Mail’s “nearly a million more square miles of ocean covered with ice than at the same time last year – an increase of 60 per cent”.  We also challenge all and sundry to watch our video and then loudly proclaim, with a straight face, that “an unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia’s northern shores”.

60 Per Cent of Nothing?

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Our title today is an allusion to Bill Bruford’s “Five Percent For Nothing”, from the 1971 album “Fragile” by Yes. Here’s what the cover looks like:

Fragile cover art, by Roger Dean (image Wikipedia)

Them:

A chilly Arctic summer has left nearly a million more square miles of ocean covered with ice than at the same time last year – an increase of 60 per cent.

Us:

According to the NSIDC once again the numbers look like this:

NSIDC daily Arctic sea ice extent chart, highlighting September 7th 2013
NSIDC daily Arctic sea ice extent chart, highlighting September 7th 2013

The sums are obviously rather tricky, so we’ve enlisted the aid of a spreadsheet. Here’s what it reveals to us:

Metric Date 2012 2013 Increase
NSIDC Daily Extent (million km²) Day 249 3.558 5.236 47.2%
NSIDC Daily Extent (million km²) Sep 8th 3.523 5.179 47.0%
NSIDC Daily Extent (million km²) Aug 27th 3.94 5.632 42.9%
NSIDC Daily Extent (million km²) Aug 15th 4.845 6.159 27.1%
NSIDC Monthly Extent (million km²) August 4.71 6.09 29.3%

Verdict:

Whichever way you look at things, on a “same time last year” basis at least, the magic number of 60% seems to be out of reach. Whatever the arithmetic David Rose actually performed, whether mentally or on his pocket calculator, it would appear not to involve comparing like with like. We have asked David and the Mail on a number of occasions what numbers he started from and what calculations he performed. We have received no answers as yet.

Getting back to our title, when you start to look at Arctic sea ice volume instead of extent, 160% of almost nothing is still almost nothing:

Video courtesy of Andy Lee Robinson

Small print: We have yet to double check all the numbers in our simple spreadsheet. The NSIDC web site is still down today.