Tag Archives: CryoSat-2

The 2016 Arctic Winter Sea Ice Puzzle

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Professor Judith Curry recently posed the following rhetorical question on her “Climate Etc.” blog:

Arctic sea ice extent has been anomalously low this winter. The greatest anomalies are in the European sector, specifically in the Barents Sea. To what extent are the anomalies associated with warm temperatures?

Which she answered as follows:

So, what might be causing this particular anomaly? Some possibilities are:

  • Gobal warming (January 2016 was warmest Jan on record, according to the surface temperature analyses

  • Multidecadal oscillations (e.g. stadium wave) predicts ice recovery to be occurring in the same region (European Arctic) where we see the sea ice decline).

  • Seasonal weather circulation patterns – this has been a year with with unusual weather patterns, with both low temperature and high temperature records being set.

As regular readers will already be aware we have been blogging about anomalously warm temperatures in the Arctic all year and so felt well qualified to contribute to the “debate”. What a job that turned out to be! Early on in the proceedings the anticipated pronouncement was made by one of Judith’s “denizens”. A link to a ludicrously inaccurate article on Watts Up With That accompanied by the following words of wisdom:

Other measures are high.

Which of course they aren’t! Instead of stating the bleedin’ obvious Professor Curry replied:

I spotted this, no idea what to make of it.

You would think she and her denizens would therefore have been pleased when I attempted to explain to her what to make of it, but you would have been mistaken. The icing on the ad hominem cake was the aforementioned Anthony Watts driving by to accuse me of all sorts of nefarious activities without providing a single shred of evidence and then running for the hills when invited to actually prove his ludicrous allegations.

Since the denizens of “Climate Etc.” aren’t particularly interested let’s take stock here instead shall we? After every Arctic area and extent metric under the sun sitting at “lowest *ever” levels for weeks a recent increase in coverage on the Pacific side of the Arctic has changed that. The most up to date example of that is the JAXA/ADS extent, which currently looks like this:

vishop_extent-20160228

The latest reading is the merest whisker above 2015’s record low maximum. However in other respects things are most certainly not comparable with 2015. See for example this concentration comparison from Andrew Slater of the NSIDC:

ice_con_delt_20160227

Much more ice on the Pacific periphery where it will all have disappeared by September, as opposed to much less ice on the Atlantic side, even well to the north of 80 degrees latitude where the sun still does not shine. Here’s a video revealing how the sea ice North of the Pacific Ocean has been reacting to the sequence of hurricane force storms that have been passing through the area over the past couple of months:

Now let’s take a look at “near real time” Arctic sea ice thickness as measured by the CryoSat 2 satellite:

CryoSat2_20160225

Notice the absence of any thick ice in the Beaufort and Chukchi Seas, an obvious difference from last year? Notice too the large area of thick ice that looks as though it’s heading towards the Fram strait exit from the Central Arctic. Here’s another video, this time of sea ice movement over on the Atlantic side of the Arctic Ocean:

Those dark areas between Svalbard and the North Pole are suddenly starting to look as though they represent reality rather than a mere “artifact”, although perhaps they are merely transient evidence of yet another Arctic “heat wave”?

Inside the BBC’s Arctic Sea Ice Science

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I’m sure we’ll get stuck into to some real science eventually, but for the moment we’re still taking a long, hard look at mainstream media coverage of the latest learned journal article on Arctic sea ice to be misinterpreted by the media. Compared to some others one might mention the report on the BBC web site about the new CPOM paper in Nature Geoscience entitled “Increased Arctic sea ice volume after anomalously low melting in 2013” was relatively accurate. Entitled “Arctic ice ‘grew by a third’ after cool summer in 2013“, it said that:

Researchers say the growth continued in 2014 and more than compensated for losses recorded in the three previous years.

The scientists involved believe changes in summer temperatures have greater impacts on ice than thought.

But they say 2013 was a one-off and that climate change will continue to shrink the ice in the decades ahead.

The Arctic region has warmed more than most other parts of the planet over the past 30 years.

Satellite observations have documented a decrease of around 40% in the extent of sea ice cover in the Arctic since 1980.

and

The researchers used 88 million measurements of sea ice thickness from Cryosat and found that between 2010 and 2012, the volume of sea ice went down by 14%.

They published their initial findings at the end of 2013 – but have now refined and updated them to include data from 2014 as well.

Relative to the average of the period between 2010 and 2012, the scientists found that there was a 33% increase in sea ice volume in 2013, while in 2014 there was still a quarter more sea ice than there was between 2010 and 2012.

At this juncture one is forced to ask oneself the question that if there was 33% more sea ice in 2013 than there was between 2010 and 2012, but only 25% more in 2014 how it was possible that “the growth continued in 2014”?

Desperately hoping that the BBC might be able to explain this conundrum to us we avidly listened to Adam Rutherford’s interview with Rachel Tilling, the lead author of the paper in question, on BBC Radio 4’s “Inside Science” programme last night. We were also hoping that at long last there might be some quantification of what’s happened to the VOLUME of “sea ice cover in the Arctic since 1980”. Sadly all our hopes were dashed, and Adam never posed the vital questions.

You can download a recording of the broadcast from the link above. Adam’s interview with Rachel starts at 7:00 minutes. He begins by talking about:

The publication in Nature Geoscience this week of a new paper that shows that in 2013, which was a slightly cooler summer than average, Arctic ice had grown, not just a tad, but by a WHOPPING 41% on the previous year!

Rachel Tilling then begins by saying:

The thickness and the volume are actually the most important measurements we can get, because the area’s been really, really useful in giving us an overview of how the Arctic is changing, but it only really gives us half the picture.

Here’s the full picture, taken from our Arctic Sea Ice Graphs page. Since CryoSat-2 measurements only go back as far as 2010, this graph shows Arctic sea ice volume calculated by the PIOMAS model developed by the Polar Science Center at the University of Washington:

piomas-trnd2-201506Is that WHOPPING increase in Arctic sea ice volume from 2012 to 2013 clear to you now? At 11:00 minutes into the programme Adam says:

You can see how this is going to be interpreted. You know, with 30 years of Arctic sea ice shrinking, and then suddenly it gets bigger, you’re still OK with climate change being a real thing, and global warming being a real thing?

I can see that very clearly Adam, thanks for asking, and YES is the answer to your final question. It still wasn’t clear to me whether that would be clear to Adam’s listeners however, so I posed a pertinent question on Twitter first of all:

That didn’t elicit any response, so then I tried following Adam’s instructions at the end of the interview to:

 Do let us know what you think – [email protected]

This is what I thought:

Hello Adam,

Further to your recent interview with Rachel Tilling, and your joint Twitter conversation with my alter ego “Snow White”, I’d like to reiterate how disappointed the two of us are that during your conversation with Rachel there was no mention of “41% of nothing”. Twitter speak for “Doesn’t anybody at the BBC have the faintest idea what Arctic sea ice volume was 30 years ago, in April and in October?”

By way of additional context see e.g.

https://greatWhiteCon.info/2015/07/an-inconvenient-truth-about-the-mails-climate-coverage/

http://www.carbonbrief.org/blog/2015/07/cool-arctic-summer-brought-brief-recovery-in-2013-sea-ice-loss/

https://greatWhiteCon.info/resources/

Yours in dismay,

Jim Hunt

and this is the response I got from BBC Inside Science:

Dear Sir or Madam

Thank you very much for your email. While all emails are read – and we appreciate input from listeners – we cannot reply to each one individually. There are simply too many!

For more information about Inside Science, please go to our webpage:

Inside Science, Radio 4
http://www.bbc.co.uk/programmes/b036f7w2

For individual programmes, click on ‘Episodes’.
http://www.bbc.co.uk/programmes/b036f7w2/episodes/guide

Once you have located a particular programme page, you will see a link to ‘Listen now’- on the picture of Dr. Adam Rutherford.
‘Related Links’ are found further down on the right hand side of the page.

Downloads/Podcasts of Inside Science are available at:
http://www.bbc.co.uk/podcasts/series/inscience

Thanks again and do keep sending your comments in – listener feedback helps us make better programmes for you.

Yours sincerely

Inside Science, Radio 4

 

Meanwhile, over on Twitter:

An Inconvenient Truth About The Mail’s Climate Coverage

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A new paper has just been published by the CryoSat-2 team at University College London. The lead author is Rachel Tilling, a PhD student in the Centre for Polar Observation & Modelling at UCL. We’ll get on to the science in due course, but first let’s take a look at how Rachel’s paper has been reported in the Great British mainstream media. In a headline redolent of our old friends at the Mail on Sunday The [headline writer for the] Guardian’s Damian Carrington proclaims that:

Arctic sea ice volume showed strong recovery in 2013

Cooler temperatures revived sea ice levels suggesting a rapid recovery was possible if global warming was curbed, scientists say

Yesterday wasn’t a Sunday, so David Rose was writing in The Spectator instead of The Mail, asking rhetorically:

Was the global warming pause a myth?

Of course it was David! We explained that to you back in January!

The Daily Mail Group couldn’t let a juicy headline go begging just because it’s midweek, so an anonymous leader writer came up with this one:

Climate change and an inconvenient truth

The “Daily Mail Comment” continues:

In a major report last year, the Intergovernmental Panel on Climate Change gave a grave assessment of how man-made global warming was rapidly destroying the Arctic ice cap.

Steadily increasing temperatures had made the pack ice contract by up to 12 per cent between 1979 and 2012, leading to rising sea levels which threatened to swamp coastal regions – not to mention endangering stranded polar bears.

By the middle of the century ‘a nearly ice-free Arctic Ocean’ was likely for a large part of the year, the report predicted.

How interesting then, that the latest analysis of 88million measurements from the European Space Agency’s Cryosat satellite show the northern ice-cap INCREASED by a staggering 41 per cent in 2013 and, despite a modest shortage last year, is bigger than at any time for decades.

After that it prattles on about the “pause”, so for now let’s take a look at the paper that’s got the papers so excited. For some strange reason it’s title makes no mention of a “strong recovery in 2013”, instead describing:

Increased Arctic sea ice volume after anomalously low melting in 2013

Searching the paper for the word “recovery” returns zero results, so you may well be wondering what it actually does say? Here’s a pertinent, albeit brief, extract from the abstract:

Between autumn 2010 and 2012, there was a 14% reduction in Arctic sea ice volume, in keeping with the long-term decline in extent. However, we observe 33% and 25% more ice in autumn 2013 and 2014, respectively, relative to the 2010–2012 seasonal mean, which offset earlier losses. This increase was caused by the retention of thick sea ice northwest of Greenland during 2013 which, in turn, was associated with a 5% drop in the number of days on which melting occurred—conditions more typical of the late 1990s. In contrast, springtime Arctic sea ice volume has remained stable.

Let’s compare that with the Mail’s version shall we? Whilst searching the paper for the word “ice” returns lots of results a search for the word “cap” returns zero results, just like “recovery”. Any investigative journalist (or leader writer) who had investigated Wikipedia would have discovered this:

An ice cap is an ice mass that covers less than 50,000 km² of land area (usually covering a highland area). Masses of ice covering more than 50,000 km² are termed an ice sheet.

Thus the Arctic Ocean is not covered by an “ice-cap [that] INCREASED by a staggering 41 per cent in 2013” because, as it’s name suggests, it’s an ocean and not a land area. Assuming for the moment that the Mail leader writer is in actual fact referring to sea ice cover in the Arctic, then according to Rachel Tilling’s paper CryoSat-2 “observed 33% more ice in autumn 2013”. Where did the Mail’s “41%” come from then? Their patent pending hot air generator in reverse gear?

Moving on, the Mail must also have a top secret time machine hidden in the basement of Northcliffe House that will enable their leader writer to travel back and change history, because here once again is Andy Lee Robinson’s graphic visualisation of what’s really been happening to the volume of sea ice in the Arctic over the past few decades, albeit using PIOMAS sized ice cubes rather than the CryoSat-2 flavour:

Needless to say I have already lodged an official complaint about the antics of The Daily Mail’s imaginary time machine. If you would like to do as well then here is the appropriate form to fill in:

http://dailymail.co.uk/readerseditor

For any IPSO case officers (or Guardian writers) that might be watching please feel free to read all about 41% of nothing, and if you prefer graphs to moving pictures here’s one that shows Arctic sea ice volume in Spring from our PIOMAS regional volume page:

 

Meanwhile, over on Twitter: