Will the ice in the Arctic Ocean disappear?

The IPCC and climate science community are telling the world that the Arctic ocean may some time soon be free of sea ice in summer. Countries bordering the Arctic basin, and some beyond, are clamouring to lay claim to oil and gas reserves rumoured to lie below the seabed.

The sea ice record of the Arctic is in two parts. The satellite era record begins in 1979. Prior to that it is based on human, surface observations. Splicing the two methods together may clearly present problems. The pre-1979 reconstruction preferred by the IPCC is that by Walsh and Chapman that essentially shows no sea ice extent variance. The satellite record essentially shows continuous loss since it began and splicing these two together produces a perfect sea ice hockey stick.

In this post, a number of Arctic sea ice reconstructions are reviewed and compared with Walsh and Chapman. These other reconstructions tend to show much more natural fluctuation in historic sea ice levels. Furthermore, these other reconstructions tend to agree with the surface thermometer record of air temperatures while the Walsh and Chapman / IPCC view of history does not.

A number of countries bordering the Arctic seem to be convinced that the Arctic Ocean will shortly become partially or completely ice free and are taking steps to stake their claim to the huge volumes of oil and gas that will supposedly become exploitable as soon as the ice disappears. As the Daily Mail recently put it:

The Arctic is the only region in the world where borders remain unregulated, and Russia, Norway, Denmark and Canada have all made submissions to the U.N. claiming ownership of the Arctic seabed and its buried treasures. Russia is beefing up its military presence in the Arctic, sending troops and missiles to strengthen its position in the competition for the region’s extensive oil and gas reserves. As well as deploying advanced anti-aircraft missiles to the region, President Vladimir Putin is overseeing the completion of six new bases designed to see off foreign competition for the natural resources. But Russia is not the only nation to have stepped up its military designs on the Arctic. British and American submarines have recently been located in the Arctic Ocean, while Canada has also increased its military presence and President Obama has proposed to launch the U.S. icebreaker fleet …..

The US Navy has already set forth its strategy to contain Russia in its Arctic Roadmap . Here is the unclassified version:

Ensure United States Arctic sovereignty and provide homeland defense; Provide ready naval forces to respond to crisis and contingencies; Preserve freedom of the seas ….

And a war over oil would not be unprecedented. The oil embargo the US imposed on Japan in 1940 was what triggered the Japanese attack on Pearl Harbor.

It is of course to be hoped that all this is saber-rattling and will never come to anything. Yet it marks a first for climate change. We’ve all heard the wild claims of how climate change has already contributed to wars in Africa and to the emergence of IS in the Middle East, but here we have a projected climate change impact that has not yet happened – and which may never happen – that’s already setting the groundwork for possible armed conflict in the Arctic.

The question this post addresses is, how good are the data that back up the IPCC’s claim that the Arctic will become ice free at some time in the foreseeable future? Do we know enough about the historic behavior of Arctic sea ice to be certain of anything? Or is the world being led around by the nose by climate model projections based on inadequate data?

We begin with the IPCC’s Arctic Ice extent time series, which is used as the basis for ice extent model projections. It’s shown in Figure 4.3 (a) of the IPCC’s Fifth Assessment Report and reproduced below as Figure 1. The series is constructed by combining the post-1978 satellite record with the pre-1978 Chapman and Walsh and HadISST1 surface observation reconstructions. It’s basically another hockey stick, with the downward bend after 1950 coinciding with the claimed increase in man-made radiative forcings after the middle of the 20th century. Note that Figure 4.3 (b) is omitted for clarity:

Figure 1: Annual Arctic ice extent since 1870 according to the IPCC .

And Figure 2 shows a model projection of future Arctic ice concentrations developed from it:

Figure 2: Model-simulated Arctic sea ice concentrations projected to 2100

The IPCC series shown in Figure 1 does, however, exhibit a few suspicious features. One is that the blade of the hockey stick is constructed from satellite measurements and the shaft from surface ice observations, but here we will give the IPCC the benefit of the doubt and assume that these features are not artifacts of the use of two different data sets. Instead we will concentrate on two other potentially suspicious features:

1. Other Arctic ice-extent time series do not match the IPCC’s series.

2. The IPCC’s series conflicts with surface temperature observations.

Discussing these in sequence:


1. Other Arctic ice time series do not match the IPCC’s series.

There are a large number of Arctic sea ice reconstructions based on historic ice-edge observations that rarely see the light of day but which don’t show the same trends as the IPCC reconstruction, and below I show a selection of them. But first a map of the Arctic seas for orientation purposes:

Figure 3: Location of the Arctic seas

The first reconstruction is shown in Figure 16-3 of the 2007 AR4, reproduced below as Figure 4 (the original data are from Vinje 2000) . It shows a gradual ice loss in April sea ice extent over the Nordic seas since 1865, but the rate of ice loss decreases rather than increases with time and there is no sign of an acceleration after 1960. The series covers only the Nordic seas and shows only April data, but it is nevertheless difficult to reconcile with the IPCC series, which bends in the opposite direction. (Vinje’s conclusion, incidentally, was that “ the recent decrease in ice extent is within the range of variability observed since the eighteenth century”):

Figure 4: Vinje ice extent time series, Nordic Seas, 1865-2000

A more directly comparable data set is that of Zakharov, as described in Johanessen et al. 2004. Zakharov covers about two-thirds of the total area of the Arctic Ocean – a much larger fraction than the Nordic Seas plot shown in Figure 4 – and is compared with the “Walsh” contribution to the IPCC reconstruction (the red line in Figure 1) in Johannessen et al’s Figure 5. Similar short-term trends are visible in both data sets but the longer -term trends are quite different, with Walsh showing rapid ice loss after 1950 and Zakharov showing hardly any.

Figure 5: Time series derived from Zakharov sea ice data set, 1900-2000

The Polyakov et al 2003 data set also covers the four “arctic” (Siberian) seas and shows present-day ice extents which are not that different to those of 100 years ago. Polyakov et al. conclude as follows: Examination of records of fast ice thickness (1936–2000) and ice extent (1900–2000) in the Kara, Laptev, East Siberian, and Chukchi Seas provide evidence that long-term ice thickness and extent trends are small and generally not statistically significant.

Figure 6: Polyakov time series, Arctic seas (Y scale in 1000km2)

Figure 7 shows Polyakov’s series for the four seas.

Figure 7: Polyakov time series for the four Arctic seas (Y scale in 1000km2)

Next come Divine & Dick (2004), who present the Nordic Sea ice edge anomaly reconstructions for April, June and August shown in Figure 8. Like the Vinje data in Figure 2 they show a gradual overall decline in sea ice extent since the late 1800s but no evidence for a recent acceleration in the rate of ice loss:

Figure 8: Divine & Dick April, June & August ice edge anomaly series, 1860-2000

I have more plots of Arctic ice extent reconstructions that I can no longer find the links for but which I am going to show anyway because I have no reason to believe there is anything wrong with them. First, Miles et al (2007) show an increase in the rate of sea ice loss, but starting around 1890, not in 1970 (Figure 9):

Figure 9: Miles et al. ice-edge anomaly series, Greenland and West Nordic Seas

Ogilvie (1992) also shows an acceleration in the rate of ice loss in the Nordic seas, but in this case beginning around 1850:

Figure 10: Ice extent, Nordic Seas, “mainly based on logbook observations and Icelandic coast observations by Ogilvie (1992):

Then there are the thumbnails shown in Figure 11, which I believe are from Vinje: Do they define the Little Ice Age?

Figure 11

Then there’s the Hill reconstruction of winter sea ice extent off Newfoundland, which shows sea ice beginning to retreat after 1920 but staying roughly stable since 1970:

Figure 12: Hill time series of ice extent off Newfoundland

And finally this reconstruction by Ogilvie & Jónsdóttir of sea ice conditions off Iceland, which goes all the way back to 1600 and shows more ice off Iceland now than there was 400 years ago:

Figure 13: Ogilvie & Jónsdóttir sea ice index off Iceland since 1600.

Above we have a dozen or more ice-extent plots that don’t match the IPCC’s version of events (Figure 1). What do they tell us? That the IPCC’s version is potentially suspect. And as discussed briefly in the second part of the analysis it becomes even more so when we inject surface temperature observations:

2. The IPCC series doesn’t match surface temperature observations.

To illustrate this point I use the four series shown in Figure 14, all of which except for Miles have been shown earlier (I have the annual ice extent values downloaded for all of them). The Vinje, Zakharov and Miles series are constructed from ice edge observations. The IPCC series is a version of the Chapman-Walsh series that closely matches the IPCC series shown in Figure 1. I have juggled the ice extent scales so that all four series plot in about the same place but have made no attempt to relate ice extents to temperature change in a quantitative sense:

Figure 14: Vinje, Zakharov and Miles ice extent series compared with IPCC ice extent series (Walsh-Chapman). The scales have been adjusted to line the plots up.

Figure 16 now plots the four series against Arctic annual mean surface air temperatures since 1880 (my estimates based on 49 Arctic surface station records). The scales are again adjusted so that they line up and the ice extent scales are inverted so that ice extent and temperatures move in the same sense:

Figure 15: Figure 14 ice extent series compared with Arctic surface air temperatures since 1880.

Vinje, Zhakarov and in particular Miles all show a tendency for ice extent to decrease as temperatures increase, which is what we would expect to see. The IPCC series, however, shows ice extent tracking temperature only after 1970 – a period roughly coincident with the satellite measurements. It shows no visible response to the equally large temperature changes before that. According to the IPCC neither the ~1.5C increase in Arctic surface temperatures between 1880 and 1940 nor the ~1C decrease between 1940 and 1970 had any significant impact on Arctic sea ice extent. This is implausible.

So what’s the bottom line? Basically that we don’t have any reliable records of how Arctic sea ice behaved before the satellite data begin in 1978 (assuming that the satellite records are themselves giving us the right answer). So when the IPCC’s computer models project that Arctic sea ice will disappear at some point in the foreseeable future they are once again extrapolating into the next one hundred years without any understanding of what happened in the last. The countries that are now casting avaricious eyes towards the oil and gas bonanza that an ice-free Arctic would liberate should bear this fact in mind.

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36 Responses to Will the ice in the Arctic Ocean disappear?

  1. David Richardson says:

    Roger – thank you for an excellent bit of work. Given that climate science is happy to fiddle with data that we do know (or thought we did), it is no surprise that they will seek to fill a vacuum in our knowledge with suitably “story fitting” stuff.

    I suspect that confirmation bias is at work on both sides of the debate perhaps, but well documented historical records from 100 and 200 years ago of largely ice free areas, plus 1950’s photos of US atomic subs near the North Pole tend to support the idea of much more variability than the IPCC wants to admit.

    Not much has happened in the last few years with much variability due to weather not climate and also ocean flow in and out of the Arctic. There are reports of both thickening ice volume and substantial increases in multi-year ice. The usual area metric quoted is the low point in September or grudgingly the high point in March, but one researcher (can’t find the link now) pointed out that the minimum has large variability due to some years storms breaking up ice driving it into warmer water – not a true in situ melt as per “the theory”. This researcher pointed out that if you looked at the average area through the year it smoothed out the variability and showed little trend for the last 7 or 8 years – you could even fantasise a slight increase.

  2. Askja Energy says:

    Ok. But what if the ice has in fact been disappearing as the model suggest? And what if the reason for that may be higher temperatures due to carbon-dioxide emissions? Wouldn’t it be recklessness towards our children and future generations not to try to limit emissions?

    In addition, limiting emissions will obviously be good for peoples health. Less smog in the cities, less polluting coal plants etc.

    Just saying.

    • Euan Mearns says:

      First of all it is vitally important to not conflate CO2 emissions with particle emissions that cause smog. I’m guessing thousands will already have died in China from smog and probably none form CO2. Without energy thousands more would die. The problem is dirty power stations located in cities like we had in the UK50 years ago.

      And you need to consider a situation where NW European climate becomes colder in the next 30 years punctuated by some sever winters. We need an electricity system fit for the purpose of operating reliably in such condition or, again, thousands may die from cold.

      • burnsider says:

        As a chemist rather than a meteorologist, atmospheric physicist or the like and since this debate relates to the historical record, can I draw attention to a paper by Arrhenius (a physical chemist) from 1896 which considers the effects of CO2 in the atmosphere on the ground temperature:-


        There is nothing new under the sun, as they say. There was a debate even then about the causes of significant past planetary temperature swings (orbital, solar, atmospheric, etc) and calculations showed that the effects of increasing atmospheric CO2 would be felt more at high latitudes (page 265). Fast forward 120 years and the debate continues….

        • Euan Mearns says:

          Burnsider, the problem being that the CO2 Greenhouse as Arrhenius conceived it does not work since the main absorption bands are saturated at surface. And so enter V2, and that always makes me suspicious. V2 is radiative transfer through the CO2 column in air. This actually requires a pretty high level of physics to understand – at least it pushed me. The key variable is thermal structure at the emission height of CO2 which lies close to the tropopause. The emission height rises as CO2 ppm goes up and theoretically with CO2 emitting at colder temperature the surface must warm. If it happens to get warmer as you go up (i.e. in the stratosphere) then CO2 actually acts as a conductor and not as an insulator, conducting heat away from the surface.

          I was going to write a post on this but entered a whole new world of thermal structure of the troposphere and stratosphere and was swamped. I basically don’t trust these people and the institutes they work for. If GHCN, for example, had answered my emails thanking me for drawing attention to the mistaken manipulation of temperature data in Iceland then I would see things differently. And this incidentally is relevant to Roger’s post since the form of manipulation in Iceland converges the air temperature record with their version of the sea ice record.

          And of course the impact of CO2 greenhouse is highly dependent upon the feedbacks. Any science that only sees positive feedbacks and tries to sweep the negatives under the rug (or rather hit them into the long grass), such as more water vapour = more cloud and more heat = more convection – the principal way that heat is removed from surface.

          • robertok06 says:


            “The key variable is thermal structure at the emission height of CO2 which lies close to the tropopause. The emission height rises as CO2 ppm goes up and theoretically with CO2 emitting at colder temperature the surface must warm.”

            Bingo!… right on spot… published recently…

            “How increasing CO2 leads to an increased negative greenhouse effect in Antarctica”

            Geophys. Res. Lett., 42, doi:10.1002/2015GL066749

            … which is NOT behind paywall.

    • According to the satellite records Arctic sea ice has indeed been “disappearing”, as you put it. But is this a result of higher temperatures due to CO2 emissions? Well, that’s the whole point of this post. We don’t have enough historical data on Arctic ice even to say what Arctic ice did before the satellite era, leave alone what’s causing the present ice extent decreases, although from the work I’ve done the AMO looks like the most likely culprit. As to whether and when the Arctic ice will disappear altogether – well, we’re shooting completely in the dark on that one, whatever the Canadians, Danes, Norwegians, British, Russians and Americans might choose to believe. In fact I find it profoundly depressing that so many supposedly “advanced” nations have swallowed the ice-free Arctic line apparently without having made any effort to check whether it’s backed up by anything more than speculative computer models.

      • Yvan Dutil says:

        Well, we have century of attempt from the Royal Navy to get trough the North West passage. It is pretty obvious from those historical records, that the ice was much more stranger in the past than now.

        Also, I would like to point out that people are working to extend satellite record deeper in the past.

    • oldfossil says:

      @Askia Energy, as soon as you say “recklessness towards our children” I already know you are incapable of rational thought. My children are alive today, so are my grandchildren, and by the end of 2016 I will have at least one great-grandchild. My responsibility is towards my progeny living today, not towards hypothetical future generations living in some mythical future. Please take your tired cliches and shove them where the sun does not shine.

      • Another Fossil says:

        Couldn’t agree more. My grandfather was born in 1870s and my great grandfather 30 years before that. I would be horrified to learn he had given up anything for me – think of what mankind has learnt in the intervening time – on balance good things. I am expecting man’s ingenuity to continue.

        Can we quantify what are we giving up in this race for ever greener energy? The race is in response to a warming that may be natural or may be in part / whole induced by man; we will likely never come to an agreement. If the extreme forms of hyperbole are to be believed anything we do in mitigation is probably too late already.

        I have a huge faith in mankind’s ingenuity and adaptability; if he fails to adapt then like other life forms before him: extinction looms. But even in my family of slow breeders this is very unlikely to happen in the life of even my great great grandchildren.

        So, if I were a not to be “reckless towards our children” what tangible “thing” should I be giving up for them? Is just paying more for intermittent “green” energy enough? I suspect that for many “believers” there is no limit to what others should be giving up.

        Like many, my children have an education, a sense of curiosity, a desire to succeed and questioning of perceived wisdom – I am sure that their generation will also invent and adapt.

        My apologies for not including any data – well below the standard of this fascinating site.

  3. Dave Rutledge says:

    Hi Roger,

    Thank you for an extremely interesting post.


  4. Doug says:

    Paul Homewood did an interesting post on Arctic sea ice over a year ago, quoting from HH Lamb and including a graph of Arctic sea ice around the coast of Iceland since 800 AD. See https://notalotofpeopleknowthat.wordpress.com/2014/10/08/hh-lamb-cooling-in-the-arctic/

  5. A C Osborn says:

    Roger, there is Satellite data going back before 1979, but NASA & the IPCC do not like to show it.
    Also how did this happen if the hockey stick is true, the North West Passage “it was first navigated by Norwegian explorer Roald Amundsen with a small expedition in 1903–1906.” when today they need Ice Breakers to do the same thing?
    Reading the Wiki page on the NWP it goes back to before the Litle Ice Age, so Arctic Ice still has not returned to those pre little ice age conditions.

  6. JerryC says:

    Viewers of the reality show “Deadliest Catch” may be surprised to find out that Arctic sea ice is a thing of the last.


  7. Joe Public says:

    On 17th Sept 2012, the Grauniad proclaimed:

    “Arctic expert predicts final collapse of sea ice within four years”

    “One of the world’s leading ice experts has predicted the final collapse of Arctic sea ice in summer months within four years……..

    …… This collapse, I predicted would occur in 2015-16 at which time the summer Arctic (August to September) would become ice-free. The final collapse towards that state is now happening and will probably be complete by those dates”.”


    Place your bets now ……..

    • Graeme No.3 says:

      Wadhams came second in the Climate Prat of the Year at Pointman’s.

    • Ron Clutz says:

      And Wadhams predicted 2015 Arctic minimum extent would be 1M km2–predicted it 3 times: In June, July and August of 2015. The outcome ~5M km2. (BTW for Arctic watchers, 1M km2 qualifies as “ice-free”)

  8. The question of who owns the Arctic isn’t just Russia versus the rest all over again. Another issue is the question of who owns the Northwest Passage. Canada claims it as territorial waters and the US says it’s international waters, open to all under the “freedom of the seas” doctrine. Apparently there have already been diplomatic incidents caused by US vessels entering the Passage without getting permission from Canada first. It will be interesting to see how this plays out if the Northwest Passage ever does open up.

  9. Euan Mearns says:

    Here’s the Walsh and Chapman sea ice reconstruction from Cryosphere today. Pretty well straight lines (shafts) until satellites in 1979 and then declines. Summer sea ice begins a dramatic decline around 1955. Are we really supposed to believe that CO2 was the cause way back then?


    Its the way the satellite and surface observation data merge perfectly. And when you look at the source data its all binary code. I’m away from my desk and so can’t post this but here’s the link – Sea Ice concentration data set…


    Note also on Cryosphere that most charts plot sea ice area but the one posted here is sea ice extent which is different.

    • Are we really supposed to believe that CO2 was the cause way back then?

      ‘Fraid so, Euan. The match between the decrease in Walsh & Chapman ice extent and the increase in GISS radiative forcings after 1950 is just too close to ignore 😉

      • Willem Post says:

        We read a lot about extent, but what about ice thickness?
        Is glacier ice extent and volume correlated with Arctic ice?
        Could soot from dirty coal plants, deposited in large volumes on ice during the past 60 years, be a culprit?

        • what about ice thickness?

          Some details here. Volume plots aren’t all that different to the ice extent plots.

          Is glacier ice extent and volume correlated with Arctic ice?

          Depends on which Arctic Ice time series you select, but the Oerlemans glacier length and Ogilvie Nordic Seas ice extent plots below both show ice peaking in the early/mid 1800s and decreasing since then:

          Could soot from dirty coal plants, deposited in large volumes on ice during the past 60 years, be a culprit?

          Possibly, but I haven’t looked into it.

          • Roger Wiggin says:

            A NPR report from 2006 resonates. Thomas Painter with the (US) National Snow and Ice Center raised the possible impact of dust settling on snowfields, sea ice, etc. I wonder if China’s ever increasing coal consumption in power plants equipped with substandard scrubbing devices (possibly in lock-step with an increase in global CO2 emissions since 1955) has a more deleterious impact on Arctic ice that generally suspected (http://www.npr.org/templates/story/story.php?storyId=5415308).

  10. ristvan says:

    Roger, terrific post. I tackled the same issue, with very similar conclusions, using historical documents for ice extent and passability of the fabled Northwest Passage, in essay Northwest Passage in my most recent ebook Blowing Smoke. Lots of 2013 NWP transit vessel visuals for the numerically ( and factually) challenged.
    The only adder beyond agreeing with your general conclusion was, also took on qualitatively the accuracy of sat sea ice estimates from 1979. (The book is for the public, not for sea ice experts.) These are many and large, mostly during summer. Sats depend on the microwave reflectance difference between water and ice. In winter, ice is ice and seawater is water. In summer, freshwater melt pools on the surface of ice flows read seawater to sats, but are really underlying ice. A nice polar bear image makes the physics concept very concrete. The bears know this intuitively, and use it in their seal hunting strategies. The devil is always in the details. Regards for a very good post.

    • Rud: Thank you. Since you’ve written a book on the subject, and going off at a bit of a tangent, maybe you could answer this question. Is there any truth to the stories that the Northwest Passage was first navigated by the Chinese a thousand or so years ago, and later by Marco Polo?

      • ristvan says:

        There is no written or other historical evidence of that possible ‘truth’, so far as I know. The first recorded NWP transit took three years (but could have been done in less) by Amundsen, finishing 1906 east to west. The third official NWP transit was by RCMP officer Henry Larsen, (east to west) in just 86 days in 1944. Larsen is also credited with the second acknowledged transit, west to east, over two years finishing in 1942.
        So there can be no qualitative doubt that Arctic summer sea ice was lower in the summers of ~1900-1905 and ~ 1940-1945. Else these explorers would not have gotten through, as they obviously did. See my essay Northwest Passage for a contemporary photo of Larsen in 1944 during his summer transit to appreciate what satellite NWP ‘ice free’ actually means. Regards.

  11. dellwilson says:

    “But what if the ice has in fact been disappearing as the model suggest?”

    Indeed, what if? Is there harm in this other than sea level rise? I find it hard to be concerned over ~2mm/year rise in sea levels. Where is the alarm? Is it all hiding behind “tipping points”?

  12. Graeme No.3 says:

    The melting of floating sea ice to raise the sea level only occurs in AGW ‘science’.
    Archimedes has been homogenised from history.

  13. garethbeer says:

    Great post Mr Andrews, thank you!

  14. garethbeer says:

    I think the alleged resources present, are an excuse for countries or political blocks to stake claim to the area due to it geo-political importance and the because they can – we have the military might to do it, they why not & it’ll piss off the other side, more arms, weapons & money for certain benefactors…

    Who knows, literally who actually knows, when the ice will be gone! Most greenies couldn’t defrost a fridge – but somehow ‘know’ the ice is melting, as someone said above, impending doom is always on the horizon however the time comes… Hmmmm

    I’ve no doubt the technology exists now to explore & drill now – its who get the money can be sorted out, which means sovereignty – happening now.

  15. Graeme No.3 says:

    The Answer!! The arctic ice will be gone by 2000 see http://climatechangepredictions.org/uncategorized/5614

  16. Javier says:

    Thanks for a very interesting post, Roger.

    One aspect of Arctic sea-ice to be explored is its relation with Arctic amplification.

    Arctic amplification is now thought to be primarily due to temperature feedbacks (essentially lapse rate) that make temperate and tropical areas radiate more in response to warming than in the Arctic, with reduced albedo from reduced sea-ice area a secondary cause. This picture is complicated with the hypothesis that Antarctica has a negative greenhouse effect (the more CO2 the more cooling, Schmithüsen et al. 2015. DOI: 10.1002/2015GL066749)

    I think this fits very nicely with your figure 15 (except Walsh/Chalpman). So it all boils down to a question. If temperatures increase significantly in the foreseeable future then the Arctic could become ice-free. After all during the Eemian it was ice-free. If it doesn’t it won’t.

    So we are back to square one. I believe that a negative AMO and a reducing activity Sun preclude any significant warming for the next 20 years. I seriously doubt I will see an ice-free Arctic in my life time, and I believe it will not become ice-free in the present interglacial.

    • Some years ago I spent many hours staring at temperature records trying to figure out why multidecadal fluctuations in surface temperature, such as the “1940s peak”, were so much larger in the Arctic than they were farther south. Eventually I came to the conclusion that this had nothing to do with “Arctic amplification”. What was actually happening was that the temperature fluctuations originated in the Arctic and lost amplitude as they moved south, to the point where they had just about disappeared by the time they got to the Equator a couple of years later. But the temp records weren’t good enough to quantify time delays this short, so I never got round to writing my paper on “the Arctic, cradle of the Earth’s climate”.

      Then a few years after I had given up Wyatt and Curry came along with their “stadium wave” theory, which I take as partial confirmation of mine:

      Abstract: A hypothesized low-frequency climate signal propagating across the Northern Hemisphere through a network of synchronized climate indices was identified in previous analyses of instrumental and proxy data. The tempo of signal propagation is rationalized in terms of the multidecadal component of Atlantic Ocean variability – the Atlantic Multidecadal Oscillation. Through multivariate statistical analysis of an expanded database, we further investigate this hypothesized signal to elucidate propagation dynamics. The Eurasian Arctic Shelf-Sea Region, where sea ice is uniquely exposed to open ocean in the Northern Hemisphere, emerges as a strong contender for generating and sustaining propagation of the hemispheric signal. Ocean-ice-atmosphere coupling spawns a sequence of positive and negative feedbacks that convey persistence and quasi-oscillatory features to the signal. Further stabilizing the system are anomalies of co-varying Pacific-centered atmospheric circulations. Indirectly related to dynamics in the Eurasian Arctic, these anomalies appear to negatively feed back onto the Atlantic‘s freshwater balance. Earth’s rotational rate and other proxies encode traces of this signal as it makes its way across the Northern Hemisphere.


      What has this to do with melting ice? Not much, but it’s good food for speculation.

      There’s one other widely disregarded feature of the AMO that I will mention in passing. Its impacts are visible in both the surface air and the sea surface temperature records, but air temperatures lead sea temperatures by about seven years. Figure that one out.

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