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Coldest Winter in 1000 Years Cometh. Not.

Filed under: — stefan @ 4 December 2010

This claim circulates in the internet and in many mainstream media as well: Scientists have allegedly predicted the coldest winter in 1,000 years for Europe. What is behind it? Nothing – no scientist has predicted anything like it. A Polish tabloid made up the story. An interesting lesson about today´s media.

By Stefan Rahmstorf and Olivia Serdeczny

We had read about it a few times and last Wednesday even were asked by German TV about the allegedly coldest winter in 1000 years, predicted by (depending on the source) Polish or Russian climatologists or meteorologists. Reason enough for us to take a closer look at the story behind the story.

It did not take much googling to find the source: various articles on the internet name the Polish scientist Michał Kowalewski, sometimes in the Russian spelling version of Mikhail Kovalevski. A few clicks later we arrive at the original article with Kowalewski´s quotes. Except that Kowalewski does not predict a record winter there – the “millennium winter” merely appears in the headline. A closer reading of the article quickly reveals: the quotes were answers to questions concerning the role of the Gulf Stream for Europe´s climate. The frosty temperatures are hypothetical effects of a breakdown of the Gulf Stream – which, as Kowalewski points out, can be pretty much ruled out.

We asked Kowalewski for his comments on the media coverage and promptly got his answer in an email from Warsaw:

The reports in some media are absolutely unbelievable. A journalist who interviewed me for radio had asked me about the theoretical climatic effects of a breakdown of the Gulf Stream. I answered that this purely hypothetic scenario would lead to much colder winters in Poland. A few days later I found on the internet the article of a journalist who mixed his own words with some of my quotes without their context so well that a completely new meaning came out. An absolutely absurd thesis. My quotes as such are correct, so I was not able to demand a correction.

Winter has Europe in its grip: the Süring-building of the Potsdam Institute.

It’s an interesting and insightful tale how this story spread. Here is a brief chronology:

September, 10. Michał Kowalewski is interviewed by the Polish radio station The same day the website of a Polish tabloid,, publishes an article with the headline of a „millennium record winter“ („once-in-a-millennium winter“). A certain Gianluigi Zangari is being quoted at the outset. He has apparently claimed to have found a slow-down of the Gulf Stream in satellite data, which he attributes to the BP oil spill (we did not follow this bizarre claim to the source). Subsequently Kowalewski´s radio interview is brought in – in order to explain the Gulf Stream and its effects on climate in general.

September, 12. „Fakt“, a Polish tabloid, writes „Millennium Winter is Coming!“ Again the BP oil spill is blamed. This time, however, without any reference to Zangari, so readers could easily be left with the impression that this is Kowalewski´s idea.

September, 22. The Voice of Russia reports that the Polish scientist „Mikhail Kovalevski“ is worried about the Gulf Stream breaking down, which Russian scientists counter as being an exaggeration.

Oktober, 4. The Russian RT News Service predicts „The coldest winter in 1.000 years“. Which is explained by the Gulf Stream having slowed down by half. RT refers to Polish scientists: “Polish scientists say that it means the stream will not be able to compensate for the cold from the Arctic winds. According to them, when the stream is completely stopped, a new Ice Age will begin in Europe”. This is where the Russian Vadim Zavotschenkow enters the scene. However, he mentions merely a cold winter: “Although the forecast for the next month is only 70 percent accurate, I find the cold winter scenario quite likely”.

Oktober, 4. The “climate sceptics” website wattsupwiththat, noted for their false reports, takes up the RT piece, presents it together with The Voice of Russia and mentions „Mikhail Kovalevski“. Watts seems to be the bridge for the story´s crossing into the western media. Is it just coincidence that the „record cold winter“ story nicely suits the political agenda of the climate sceptics?

From then on, the story is repeated on many other European media, including serious newspapers and television.

It is staggering how one journalist just copied another, sometimes even embellishing the story, without ever bothering to check the source or ask Kowalewski himself. It took us less than ten minutes of googling to get serious doubts about whether this story was real. The familiar pattern of „Chinese whispers“ emerges here once again – the same that widely spread the false whatevergate-stories.

But the often self-righteous free western press can actually learn a lesson from its Chinese counterpart in this case. The Chinese news agency Xinhua checked the story and issued the following on October, 20.:

A forecast attributed to Polish scientists of the coldest European winter in 1,000 years has drawn plenty of media attention recently but investigations by Xinhua reporters have cast doubts on its veracity.

p.s. There are, by the way, scientifically well-founded attempts to explain the currently cold weather in Europe. The basic check for seriousness: a peer-reviewed journal source is provided, and according to Google Scholar the author has a decent publication record. A millennium-record-winter, however, is not being predicted there.

p.p.s. Should your newspaper have also reported this turkey, feel free to write a polite letter to the to editors asking for a correction. It is only if readers demand published information to be verified (or if needed corrected) that something will change to the better.

This article is adapted from the German original at KlimaLounge.

Olivia Serdeczny is a scientist with the Potsdam Institute for Climate Impact Research in Germany.

114 Responses to “Coldest Winter in 1000 Years Cometh. Not.”

  1. 51
  2. 52
    Susan Anderson says:

    This is a nice exposition about the relationship between hot and cold in the north: note the horseshoe in the graphics around Greenland and the North Pole, where there used to be a solid. The video is particularly good, starting just before minute 8 and going on for not too long. Although there’s lots else good in it, if your time is limited the explanation is one of the best I’ve seen on this subject, which I find interesting and logical (just from watching MSM weather reports and maps); why shouldn’t cold weather come from the Arctic as it warms?

  3. 53
    Michael K says:

    Not all journalism is bad. There are some interesting things on Russia Today, but one has to keep in mind their overall perspective, rather like one does with the BBC or CNN.

    But corporate, western, media is losing credibility because increasingly the structural bias it conforms to is being recognised. There are notable and noble exceptions to the overall level of conformity, but sometimes one thinks they are only there as a form of ‘window dressing’ to disprove the theory that the media is absolutely under state/corporate control.

  4. 54
    Radge Havers says:

    Edward Greisch @ 51

    Hmm. Sounds like Revkin is heroically saving the day for uncertainty.

    “Likely.” An exercise in weasel language. Now you could say that if you toss a coin, it is equally ‘likely’ that it will turn up heads as tails.

    No wonder the well recommended deniers are shouting boo-yah. Who really is being equivocal (or unequivocal as the case may be)?

  5. 55
    Peter Hearnden says:

    Ok, I’ve had a handle on what is going on in the atmosphere for decades but boy are sentences (in the linked to article) like “The simulations demonstrated that lower-troposphere heating over the Barents-Kara Sea in the eastern Arctic caused by the sea ice reduction may result in a strong anticyclonic anomaly over the Polar Ocean and anomalous easterly advection over northern continents and a consequent cooling.” hard to get to grips with because they can be distilled, with only the very slightest mischief, into ‘Hah, so now they say “Warming equals cooling”‘.

    The trouble is this warming isn’t just local it’s near European if not continental – it must have an impact on global figures? Humm, then global warming = slight global cooling? Crikey, I find that hard to buy, and I’m as convinced as they come, what about the tabloid/blog science willingly led people? Does this mean it’s not as simple as trend warming, but it’s perhaps trend warming with a hefty blip of some decades for some of us (Europe/NW Europe?) while the Northern Hemisphere responds to the Arctic Sea ice’s demise? So where else is going to warm faster to keep warming on trend (a trend allowing for the slight solar quieting?)?

    And, why isn’t global warming simply on trend for us in Europe – gradually just gradually (on trend) overwhelming us? The forcings increase, the oceans warm, the pressure on the climate increase but we see a winter (a very early winter – late Autumn as well) so cold it’s (clue perhaps) got an unreal feel to it. But, explaining that, as I say, sheesshh.

    So, what do I say???

  6. 56

    Warming the Arctic by 5 to 10 degrees C still makes it a much colder placer than anywhere except the Antarctic.
    The La-Nina NAO explanation from BBC weather staff is nice, but Negative NAO’s and La-Nina’s occurred in the past. Global warming over time affects the regular effects from oscillations due to the drastic Arctic sea-scape changes. In this NW European cooling case, there is a propensity for Low pressure cyclones to stay in place due to much more open Polar sea water , also allowing more cyclones from the South to penetrate the usual Polar cold air barrier. At some locations this channels a more steady uninterrupted colder or warmer air channel giving a stable unusual temperature setting for some rather big regions.

  7. 57
    Brent Hargreaves says:

    May I ask a question? Has the confidence of the owners or readership of this website reduced in the light of the data and developments of the past year?

    [Response: Confidence in what? – gavin]

  8. 58

    But to get to science, maybe some more discussion about how the ocean circulation works would be worth while.

    I hear everyone shout out, “How might we get that going?”

    And I answer, “Let’s review that bit about carbon isotope dating of the deep ocean waters.”

    “I am wondering about the validity of dating water.”

  9. 59
    WhiteBeard says:

    #18, JiminMpls,

    Somewhat off topic, but tying-in to Stephan and Olivia (thanks “guys”) highly useful piece of investigation of what goes into perceptions.

    The “coastal Alaska” in your statement is a little vague. Alaska has more than twice the coastline of the rest of the US (although having the Pacific Plate interacting with the North American one and creating lots and lots of good sized islands does add some to that).

    On the temp graph at your link, the Bearing and southern Chukchi Sea coast share the cold anomaly, but the bulk of the State’s shore line temps are quite normal. The two Alaskan locations mentioned in the blurb are moderately close together, by Alaska standards, with a mere ~600 mi/1.000 km separation. I’d think that even my fellow geographically illiterate “average” American would have some notion of where Anchorage is (well maybe).

    But the mention of Cold Bay (pop ~80 and boasting one emporium/bar/bunkhouse/motel formerly known as the World Famous Weathered Inn – a particularly apt name) at the tip of the Alaska Peninsula, on the Bearing Sea/North Pacific boundary, seems likely to have been chosen as much for the associations its name and State would elicit. “Cold” Bay, Alaska resonates so much better than Narsarsuaq, Greenland.

    Cold Bay weather is quite wacky. In one stretch of less than nine months it set records for both the daily hi and lo temp for the date (Sep 25, 2000 – May 14, 2001 – Jun 16, 2001). A short observational history (< 70 years), possibly serious observational site and instrument issues, proximity to the Bearing Sea Low, and terrain contribute to the likelihood that “records” there can be mined for curious “factoids”.

  10. 60

    “p.p.s. Should your newspaper have also reported this turkey, feel free to write a polite letter to the to editors asking for a correction. It is only if readers demand published information to be verified (or if needed corrected) that something will change to the better.”

    For all of us – check the news -> climate/science/whatever for existence or NOT existence of this story, and mail them even when NOT found and give them lots of credit for not publishing this obvious faked science information, with a link to and this story.

    Really positive responses to journalists for doing a good job is vital, to give them incentive to front facts and not crap – and to be aware of as a source for finding sound material of climate science.

  11. 61
    Vendicar Decarian says:

    Author claims we’re in the grip of a mini ice age

    Gavin said: “It is the sun’s energy which keeps the earth warm and the amount of energy the earth receives isn’t always the same. I’ve looked at the evidence for global warming and while I understand and agree with a lot of it, there has been a lot missed out. A major factor is the activity of the sun.”

    There is also solar wind – streams of particles from the sun – which are at their weakest since records began. In addition, the Sun’s magnetic axis is tilted at an unusual degree. This is not just a scientific curiosity. It could affect everyone on earth and force what for many is unthinkable – a reappraisal of the science behind global warming.

    It was thought that carbon dioxide emissions rather than the sun was the bigger effect on climate change. Now a major re-think is taking place.

  12. 62
    Eric Swanson says:

    Stefan, as an expert on the Thermohaline Circulation, can you tell us, has the THC in the Nordic Seas in fact slowed down the past few years? We have seen reports that the surface waters have freshened, which might be expected to impact the THC, so how much sinking is there these days? Also, do you have any recent data on the sinking in the Arctic in general, given that the Nordic Seas are part of the Arctic Mediterranean by way of the deep sill thru the Fram Strait?

    E. S.

  13. 63
    Snapple says:

    Here is a story about a man in England who wrote a book that claims we are having a mini ice age.

    “Author claims we’re in the grip of a mini ice age”

    “These bitter winters aren’t going to last forever. The bad news is that they will go on for the next 30 years as we have entered a mini ice age.

    So says author Gavin Cooke in his book Frozen Britain. He began writing it in 2008 and it was published last year…

    To simplify, the basis of his theory seems to be sunspot activity, or rather the lack of it. Sunspots are dark, cooler patches on the sun’s surface that come and go in cycles.

    They were absent in the 17th century – a period called the “Maunder Minimum” named after the scientist, Edward Maunder, who spotted it. Crucially, it has been observed that the periods when the sun’s activity is high and low are related to warm and cool climatic periods.”

  14. 64
    Snapple says:

    Here is a real Russian quantum physicist named Sergei Zimov who who believes in global warming and has an idea about how to seal up the permafrost. What do you all think of his idea?

    Here is someone who is willing to speak up.
    I wonder if his views are given any notice in the Russian media?

    I guess Anthony Watts missed this story about a Russian scientist.

    Mr. Zimov’s name means “winter”–Zima.

  15. 65
    Snapple says:

    Sergei Zimov even has his own Wikipedia entry.

    The AP article says he hopes to slow global warming.

    The Wikipedia article notes:

    [Zimov] “hopes to back the hypothesis that hunting, and not climate change, destroyed the wildlife.

    The aim of Pleistocene Park is to recreate the ancient taiga/tundra grasslands that were widespread in the region during the last ice age. The key concept is that animals, more than temperature, maintained that ecosystem. This argument is the justification for rewilding Pleistocene Park’s landscape with megafauna that was previously abundant in the area, as evidenced by the fossil record.”

  16. 66
    Snapple says:

    Here is a Russian article (11-24-10) about the zoopark.

    Your Google translation tool is helpful.

    They study the permafrost there and greenhouse gasses, but this seems under the cover of protecting tigers.

    This project is called the global tiger initiative.

  17. 67

    #61 Vendicar Decarian

    The angle of the earth to the sun is not new information

    Any major rethink you might be talking about on that issue is most likely in the blogosphere, not the realm of science.

    And just because yet an other author has figured out that controversy sells to those that narrowly scope their examination of climate to that which supports their view, is not new news either.

    As to solar wind etc., here are some pretty pictures for you:

    Lot’s of graphs too ;)

    Economics: Balancing Economies
    October Leading Edge: The Cuccinelli ‘Witch Hunt”

    Fee & Dividend: Our best chanceLearn the IssueSign the Petition
    A Climate Minute: Natural CycleGreenhouse EffectClimate Science HistoryArctic Ice Melt

  18. 68
    Martin Vermeer says:

    Peter Hearnden #55: find a map of the world — no, not Mercator –, and highlight Europe on it. Notice how small it is?

    Natural variability is a funny thing: it’s much stronger locally than globally. There will be the occasional cold and snowy winters in Europe for some time to come; that won’t really change until globally, we’re up several degrees. Just like you may occasionally empty out the one-armed bandit, but the gambling hall will still make a profit (and you will lose if you go on playing).

    Also, global warming isn’t geographically uniform: things will move around. So, you’ll see some glaciers grow longer, even as most get shorter. And you’ll see Antarctic sea ice increase (a little), even as Arctic sea ice diminishes (a lot).

  19. 69
    Alan of Oz says:

    In a few years time people like Watts will be pointing at this claiming scientists “predicted an ice in 2010”.

  20. 70
    Chris says:

    Vendicar Decarian #61,

    If you open your windows during a cold night in winter the fact that your house gets cold doesn’t mean your central heating is broken.

    i.e. It’s possible that low solar activity could cause a cooling. But this doesn’t mean CO2 didn’t cause at least the last 30 years of global warming.

  21. 71
    Snapple says:

    Maybe you all could consider posting articles about Russian scientists who are concerned about global warming. If you read Pravda, Kommersant, etc., they make it seem like Russians don’t accept global warming; but there are articles about global warming on Russian sites.

    Marc Morano and other denialists don’t have those articles about Russian scientists on their sites; they only have the big media that is giving the Gazprom line. Still, Russian scientists do express concerns about global warming; they are especially concerned about the possibility that a lot of methane could be released and accelerate the warming.

    Maybe you could draw the attention of the Western media to these stories, as the AP has done.

    Maybe you could feature what the AP article said on your site as a good example of journalism.

    Zimov’s theory is that repopulating the permafrost with grassland animals will make the permafrost gradually become covered with soil, grow grass and hold in the methane.

    He believes the animals disappeared mainly because of over-hunting, not climate changes.

    He tells readers that scientists all over the world are trying to solve the complicated problem of climate change and global warming.He calls the release of methane dangerous.

    I started some links here, but have to read the Russian more so I don’t misunderstand what they are saying.

    They want grassland animals but also keep talking about getting tigers. Perhaps this makes the idea more exciting, but it seems the tigers would eat the grassland animals. He already jokes about a “hooligan” bear.

    I have no way of judging if this scientists’ idea has merit and would appreciate some opinions.

    Turning the permafrost into a grasslands sounds like an ambitious project.

    A few links:

  22. 72
    Snapple says:

    This scientist is featured in Science Magazine.

    I think its pretty pathetic that the denialists only write what Pravda and Kommersant say as if these Russian scientists don’t even exist. It is really ignorant for Senators and other politicians just to be promoting the Russian propaganda. Gazprom controls a lot of the big media, but not everything.

    Russian people are only a few generations from the land, and they are very interested in nature topics.

  23. 73

    Correction to my #67

    The angle of the earth to the sun is not new information, it’s old information. In fact the precession of the equinoxes is very old information.

    Aristarchus of Samos (c. 280 BC) is the earliest known astronomer to recognize and assess the precession of the equinoxes at almost 1º per century (which is not far from the actual value for antiquity, 1.38º).

  24. 74

    I need help from my betters with an OT problem. Hank? Ray? Martin? Barton? Gavin/Jim/Eric/Mike/Raypierre? Anyone?

    [Apologies for dropping this OT comment here, but I’m unsure where to put it. At least it fits in with the idea of misreporting evidence. I’m just not sure who’s doing the misreporting!]

    Skeptical Science recently had a post adding weight to the idea of CO2 being the cause of recent warming, due to the difference in signature between greenhouse gas versus solar warming, i.e. warmer nights versus days, and warmer winters versus summers.

    A denier pointed out — correctly, I thought, and so I’ve been defending his logic there — after all, truth is truth — that because we expect a sizable positive feedback from H2O (and CO2, and ultimately CH4), one should not be able to easily distinguish warming from different forcings, that they would all carry the same features. They might carry them to a different degree, but if 1C warming from a forcing causes 2C positive feedback (in albedo, H2O, and CO2/CH4 responses, but dominated by the GHGs), to give a net 3C climate sensitivity, then the GHG feedback component in all cases should be fairly large and so all warming should involve warmer nights/winters.

    One commenter tried to argue (as evidenced by the original post itself) that because warming prior to 1979 demonstrated no such signature, it proved that GHG-forced warming differs from other warming. [As an aside, as arguments go, this is bad. It amounts to proving that the signature difference exists by assuming that recent warming is from GHG, and then goes on to argue that this proves that recent warming is from GHG, because it has a different signature. If B is true, then A is true, but then since A is true, that proves B is true. Sounds like denialthink to me.]

    This whole line of thinking presents a series of problems/questions.

    Why did warming periods prior to 1979 present no evidence of GHG feedbacks (as pertains to differences in nighttime and daytime anomalies, and winter versus summer anomalies)?

    Or is it as simple as the fact that the non-GHG forcing component can/would balance/overwhelm the GHG feedback components?

    Or does it have to do with a delay in feedback responses, since it will take time for the oceans to warm and for the H2O and CO2 feedbacks to be felt.

    But if so, couldn’t one argue that the GHG warming we see today is merely the feedback response to pre-1940 warming, delayed by aerosols in the 1940-1970 period?

    Is the argument that GHG warming will carry a different signature truly valid, and if so, how does the expected strong positive GHG feedback response fit into the picture? How can this work?

    Can the differences between the two be quantified and so incorporated into the argument (i.e. how much winter vs. summer, night vs. day, forcing vs. GHG feeback vs. non-GHG feedback, for each)?

    It seems to me that if this can’t all be explained, the warming prior to 1940 (without a GHG signature) implies that the positive GHG feedback response is negligible, and climate sensitivity is much lower than predicted. That’s obviously wrong.

    Things just don’t fit together properly.


  25. 75
    Eric Swanson says:

    Re: #62

    To add to my comment above and give more emphasis to my question for Stefan, it appears that the recent wind patterns over the North Atlantic are beginning to push the surface waters of the Gulf Stream back toward the northwest. Last winter, that same pattern occurred and the Gulf Stream water flowed into the Labrador Sea. No wonder the UK and Northern Europe experienced a rather cold winter last time around. This year, the winter months could turn out to be a repeat of last winter. Are we seeing a new pattern in winter weather? Only time will tell…

    E. S.

  26. 76
    Kevin Stanley says:

    V. D. @ 61, re:
    “there has been a lot missed out. A major factor is the activity of the sun.”
    “It was thought that carbon dioxide emissions rather than the sun was the bigger effect on climate change. Now a major re-think is taking place.”

    I’ve been hearing about this since I started paying attention in 2006, and I’m sure it had been going on for years before that. I was tempted to be sarcastic in my response because I have come to feel contempt when I see this type of thing still being repeated, but I suppose that doesn’t really help. Instead I’ll just repeat a few facts, that apparently need repeating no matter how many times they’ve been said before:

    1)Solar activity was never left out of the “big picture” in climate science.

    A quick glance at IPCC WG1 reports, a search on google scholar, browsing through past RealClimate posts, and probably a dozen other easy activities performable right there at your own computer will allow you to confirm this for yourself. If you have any interest in doing so, that is.

    2)Expertise really does exist.

    Any time someone claims to have overturned the standard position of experts in a field, it deserves very careful scrutiny before the claim should be accepted. Such overturning happens, of course…but very rarely, and MUCH less often than it is claimed. And when such a claim is made based on the premise that the experts have been overlooking something obvious, like climate scientists neglecting the role of the sun, you can bank on the claim being false.

    3. In science there is ALWAYS a re-think taking place, and that doesn’t take away what we already know.

    Relativity didn’t make calculations based on Newtonian physics stop working. Our understanding of climate dynamics is, necessarily, incomplete…but improvements in that understanding are going to refine what we already know, not reverse it.

    4. I like cheering for the underdog, too…but see points 1, 2 and 3 for reasons to be very careful about doing so in climate science discussions.

    In the words of Carl Sagan: “…the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright Brothers. But they also laughed at Bozo the Clown.”

  27. 77

    #73 Bob (Sphaerica)

    My general thoughts are that the signal to noise ration of the cumulative forcing was not so easily separated prior to the last 30 years.

    It is this recent period where the cumulative affects are notable and the science has more clearly identified the signal to noise ratio.

    Gavin et al. pointed out in recent work the cumulative effect and models already consider the feedback component reasonably well.

    • H20 (water) = around 50%
    • Clouds = around 25%
    • Non-condensing greenhouse gases 25%
    ◦ CO2 (carbon dioxide) = around 20%
    ◦ All other absorbers – around 5%

    Keep in mind the ocean and atmosphere are already warming. And the general effects are fitting well with the GCM’s

    Others here may help fill in the gaps

    Economics: Balancing Economies
    October Leading Edge: The Cuccinelli ‘Witch Hunt”

    Fee & Dividend: Our best chanceLearn the IssueSign the Petition
    A Climate Minute: Natural CycleGreenhouse EffectClimate Science HistoryArctic Ice Melt

  28. 78
  29. 79

    Hmmm, re. #75, 76, as I consider this, a better way to say it might be that the cumulative increase in radiative forcing did not achieve a pronounced divergence of the anthropogenic forcing in contrast to the modeled path of the climate without the large increase in anthropogenic forcing.

    Of course there are many ways to express this. I remember once working on a film, someone brought up an issue and one of the grips said, there are a million ways to do something, a hundred ways to do it right, and three really awesome ways to do it.

    Since there are many perspectives we will probably just have to keep explaining it in different ways until more people start to get it.

  30. 80
  31. 81
    Chris says:

    Bob (Sphaerica),

    Yes increased WV acts as an amplifier in both GHG and non-GHG driven warming/coolings. So you will expect to see common factors between different sources of warming because of WV amplification, but there are differences.

    If you have an increase in long lived greenhouse gasses (specifically CO2). It’ll trap heat during the daytime so will cause some daytime warming, but as convection is the major factor in dissipating daytime surface heating it won’t have such an effect as increasing solar will. Then at night when the surface is no longer actively being heated, convection dies down (doesn’t cease though) and radiation takes over as the major player. GHGs ‘trap’ infrared radiation so they have a larger effect at night, this causes more night warming and the diurnal range closes as the night warming catches up with the daytime temperatures (diurnal range being the difference between daytime max and nighttime min temperatures). Furthermore in CO2 driven warming you’ll get the stratospheric cooling (due to reduced net IR flux through the stratosphere) that’s also considered to be a fingerprint of GHG driven warming.

    However with, for example, solar driven warming due to an increase in solar energy. Most of the warming will occur during the daytime, so the diurnal range will increase. And the Stratosphere will warm along with all layers of the atmosphere that the increased solar radiation passes through.

    One crucial difference between long lived GHGs and water vapour is that WV can condense out of the atmosphere with cooling, like at night or in winter. CO2 doesn’t.

    If some hypothesised early 20th century warming caused the post 1977 linear trend in temperature. What you’d expect to see is a more rapid rise in temperature early on, then it would taper off as the warming reached the new equilibrium state. What you actually see is a linear trend post 1975 in both HadCRU & GISS (no evidence of deviation from linear in the residuals). If someone suggests such a mechanism my advice to them would be to come back when they’ve produced a model that explains the observations.

    As for why things took off in the 1970s, see this graph from GW Art:

  32. 82
    Arne Melsom says:

    Don’t think anyone’s pointed to Zangari’s report, it’s available from In it, the good doctor has observed the shedding of a Loop Current Eddy in the Gulf of Mexico. Next, he states that such an event has never earlier been observed in satellite data! (“comparative analysis with past satellite data until may 2010 didn’t show
    relevant anomalies”). All this is then brought to the obvious conclusion that the extraordinary event “may generate a chain reaction of unpredictable critical phenomena and instabilities due to strong non linearities”. Scary thing, non-linearities.

  33. 83
    Sir says:

    I was sent a link to an article in Der Spiegel that says that as a result of Global Warming “Sea Level Could Rise in South, Fall in North.”,1518,732303,00.html

    A couple of things caught my attention
    “Stammer, who is the director of the Center for Marine and Climate Research at the University of Hamburg, is familiar with the incorrect notions that lay people have, which is why he likes to present them with two numbers to shatter their illusions. “In the Indian Ocean, the sea level is about 100 meters (330 feet) below the average, while the waters around Iceland are 60 meters above the average.”
    “This striking effect is based on the law of gravity, which states that every mass attracts every other mass. Water levels are higher off the coast of Iceland for the same reason. Volcanic activity pushes heavy masses of rock out of the Earth’s interior, and those masses attract water like magnets. By contrast, sea levels are lower in the Indian Ocean because, eons ago, a meteorite most probably knocked so much rock out of the Earth’s crust there that the gravitational force attracting water was reduced.”
    The second paragraph really seems to be flawed. It would seem that the overall gravity of the earth would overwhelm continental masses that are above sea level. And the gravity of the moon pulls the tides around.

  34. 84


    I certainly wouldn’t consider myself your “better”, Sphaerica, unless maybe at constructing double invertible counterpoint or some such, but one way in which CO2 and H2O might be differentiable in terms of their GH effects would lie in the “well-mixed” aspect of CO2.

    Not much water vapor in the stratosphere–which would lead me to suspect that that well-known stratospheric cooling trend has little to do with water, but much to do with CO2 (as well as the confounding variables, of course, darn it.)

  35. 85
    John Mason says:

    Peter #55,

    I need to read up on this and have contacted a couple of authors for reprints of recent papers, but if I’m reading basic summaries correctly, there seems to be evidence for a marked change in winter circulation patterns over the N Atlantic-Arctic area as a consequence of the strong warming that has demonstrably been going on in the Arctic: this would result in the NW of Europe getting a lot more of its weather from the north round to the east in winter, as opposed to the west as per usual. At the same time the seas around e.g. the UK remain warm: as you will be aware as a fellow UK weather-enthusiast, nothing generates snow shower-streamers like convergence-zones over a warm sea that is getting very cold air advected over it.

    However I want to read up on the whole matter in more detail: the potential implications of this possibility are rather profound!

    Cheers – John

  36. 86

    Correction to my #67
    re. #61 Vendicar Decarian

    Actually, the angle of the earth to the sun is very old information. Consider early knowledge of the precession of the equinoxes:

    Aristarchus of Samos (c. 280 BC) is the earliest known astronomer to recognize and assess the precession of the equinoxes at almost 1º per century (which is not far from the actual value for antiquity, 1.38º).

    Economics: Balancing Economies
    October Leading Edge: The Cuccinelli ‘Witch Hunt”

    Fee & Dividend: Our best chanceLearn the IssueSign the Petition
    A Climate Minute: Natural CycleGreenhouse EffectClimate Science HistoryArctic Ice Melt

  37. 87
    John McCormick says:

    RE # 85

    John, you said; “there seems to be evidence for a marked change in winter circulation patterns over the N Atlantic-Arctic area”

    There might be in the flight logs and pilot observations of the thousands of Europe to US to Europe flights each late autumn, early winter, mid winter these past ten years or so.

    Perhaps there is no archival data available. But, pilots would know if things are different (changing) on their flight routes and particularly where circulation patterns are concerned. Just a thought.

    John McCormick

  38. 88

    80, 81, 84 (Barton, Chris, Kevin),

    Thanks for the help so far — but people seem to be focusing on why it’s not the sun (not an issue under contention) or how GHGs differ in signature (again, not an issue).

    My sole problem is that positive feedbacks on any forcing should introduce strong positive GHG feedbacks, and once you get that into the equation, the diurnal and seasonal differences in GHG warming should be present in all warming, not just CO2 forced warming, so it should not be possible to easily distinguish GHG forced warming from other forcings.

    At the same time, the temperature record has a clear seasonal and diurnal distinction between warming in the 20th century prior to 1979, versus after.

    [Barton — If the answer was in the page you linked me to, I’m sorry, I must have missed it. It was all useful info, but stuff I knew, so I mostly skimmed it.]

    [Chris, Kevin: Likewise, if your answer was in there and I misunderstood, please restate it… but I didn’t get it from what was posted.]

    77, 78, 79 (John),

    …a better way to say it might be that the cumulative increase in radiative forcing did not achieve a pronounced divergence of the anthropogenic forcing in contrast to the modeled path of the climate without the large increase in anthropogenic forcing.

    I think I see what you’re saying here, but it just restates the problem without really explaining it.

    One thought that I’ve had of late is that the divergence might be so great because one forcing offsets the other, particularly early on, since feedbacks are not instantaneous. Also, few feedbacks would be continuous, both because of noise in the climate system, and the fact that some involve “step changes,” or at least arise in fits and starts.

    So, my current thought, just to put play numbers together, would be that within a short period, given 0.2C of forced warming, and 0.2C of rapid (realized) feedback, and 0.2C of slow (unrealized feedback), if the forcing is solar and the rapid feedback is (always) GHG, these would to some degree offset each other (solar making days warming, GHG making nights warmer, for example). Alternately, if both were from GHG effects, the diurnal and seasonal differences would be additive and far more pronounced.

    So, in the end, it becomes a question of quantifying rather than qualifying the differences, as well as recognizing that the full weight of the feedbacks will not be felt all at once, or even instantaneously.

    It still leaves the problem that one could argue that the warming we are seeing today is merely the slow GHG feedback response to the warming prior to 1940, though.

    But this is just me thinking “out loud”. I’m still waiting for someone who feels they “know” the answer to chime in.

  39. 89
    Martin Vermeer says:

    Sir #93, the article you link to appears mostly good — the graphics on the left certainly are. The speculation in the second passage you quote though is bull… I suspect that this was made up by the journalist, not by Dr Stammer :-(

  40. 90
    John McCormick says:

    RE # 85

    John, you said: “there seems to be evidence for a marked change in winter circulation patterns over the N Atlantic-Arctic area”

    It would seem to me that the thousands of Europe-to-US-to- Europe flights each late autumn, early to mid- to late-winter would provide archival data regarding circulation pattern changes.

    Career pilots would repeatedly fly those routes also experience those changes as they fly their routes. They might also be a source of observational data over the past ten years. Just a thought.

    John McCormick

  41. 91

    #55, 85–

    We’ve gotten rather a lot of this sort of “but it’s so cold” argumentation in North America, because, for the most part, the most populous regions have warmed less dramatically than many other parts of the world–like most of Europe, for instance, if considered over the last couple of decades.

    Actually, I believe the Southeast, where I live, has yet to reach the point of net warming, if considered over the entire instrumental record–although it has been warming over the duration of the “modern warming area.” (IIRC, the 1880s were particularly warm in Dixie. And no, that’s not a personal recollection.)

    Anyway, and FWIW, I usually refer people back to the global data when confronted with these concerns. Since the issue is one of distribution of warmth, not total decrease or increase, there WILL be other warm areas. Unfortunately, the NCDC maps, like most convenient representations online, aren’t generally available till about 2 weeks after the end of the month in question, so to look at November data (for instance) we’ll have to wait another week or so. October looked liked this:

    You can often get a decent general sense of the “shape” of global temperature distribution via the NCDC sea surface temperature maps, which are updated weekly:

    We do know, for example, that the Baffin Bay area, west of Greenland, has been about 8 C above normal. (Clearly visible in the SST plot linked above.) That sounds pretty abstract for most, I suppose, but for context, Baffin Bay has an area of 689,000 km2, nearly 3x the area of the UK (243,610 km2.) Some folks will appreciate that fact, in terms of the “balance” of warmth and cold.

    Sometimes it’s worthwhile to invoke temporal context as well. For instance, at the moment here (near Atlanta, Georgia) it is unusually cold–about 14 F, counting the wind chill, equivalent to about -10 C if my quick and sketchy calculation is to be trusted. But up until December 1, it had been unseasonably warm. Folks forget not-quite-recent weather quickly, but not completely, and reminders can be effective sometimes.

    I sometimes think that this whole climate debate can be summed up in a twist on the old adage about real estate: “Three things are important: context, context, and context.” At least a whole bunch of denialist argumentation boils down to an effort to obfuscate or rule out relevant context. And accordingly, a whole bunch of my argumentation boils down to not letting them.

  42. 92


    This is where the “not your better” part comes into play; I don’t really claim to have a fully-formed “answer”–just the thought that since one of the biggest feedbacks is water vapor, and since it’s effective via greenhouse-style forcing, but with a different spatial structure than CO2, you should in principle (I would think) be able to differentiate the warming due to H2O feedback from warming directly due to CO2.

    (But maybe the practicalities would be quite intractable, I don’t know; I think at least you’d have to compare the observed summation of the two effects (plus all other forcings, of course) to various modeled scenarios. An attribution problem, albeit a slightly “off-kilter” one.)

    So this is rather inconclusive, but it does seem to me at least to go to the point you raised, ie.:

    . . .that because we expect a sizable positive feedback from H2O (and CO2, and ultimately CH4), one should not be able to easily distinguish warming from different forcings, that they would all carry the same features.

    Summing up, I think the point just quoted is incorrect in principle, since I don’t think they would in fact all carry the same signature. But I’m unsure about the practicalities of actually investigating it–and, obviously, unaware whether anyone has already attempted something directly on this point.

    One last set of comments. You wrote that:

    One commenter tried to argue (as evidenced by the original post itself) that because warming prior to 1979 demonstrated no such signature, it proved that GHG-forced warming differs from other warming. [As an aside, as arguments go, this is bad. It amounts to proving that the signature difference exists by assuming that recent warming is from GHG, and then goes on to argue that this proves that recent warming is from GHG, because it has a different signature. If B is true, then A is true, but then since A is true, that proves B is true. Sounds like denialthink to me.]

    Well, yes, there does seem to be some potential for circular argument. However, as the sort of inference that sparks investigation, the point seems reasonable–clearly, from what you’ve said, there is data to differentiate warming pre-1979 from post-1979 in terms of the diurnal structure, etc. It’s reasonable to ask, well, is this due to the post-79 warming being “GHG-forced”?–particularly since many other avenues of investigation say it has indeed been.

    Looked at from this point of view, it might seem that the key to clarifying everything for you would be solid attribution of the early 20th-century warming Callendar observed. AFAIK, though, that issue’s not entirely resolved–unfortunately.

  43. 93
    John Mason says:

    John (#89),

    This is one paper I am keen to read in full:

    Overland, J. E., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1–9.

    I’ve emailed the first author for a reprint, and will hopefully get chance to study it in the near future.

    Cheers – John

  44. 94
    wili says:

    “Overland, J. E., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1–9.”

    That does sound interesting. Does anyone else have any suggestions for the latest studies of what the consequences might be of relatively ice free Arctic for broader climate patterns in the Northern Hemisphere?

  45. 95
    thomas hine says:

    Hi Olivia!

    Maybe not the last 100 years, but the last 30-days look as cold as I’ve ever seen (must admit, I’m not nearly 100 years old).

  46. 96

    #87 Bob (Sphaerica)

    I don’t think it is just a restatement. But let me add to it to bring it along. We are trapping more heat. 1.6 W/m2 is the mean estimate. So when you add up all the meters and the time span, you can see the back-filling going on. There are fast feedbacks to consider and slow feedbacks, mixing it up with natural variation.

    As the quantities for radiative forcing build in the dam of the climate system, the feedbacks (let’s call them leaks in the dam, i.e. influences on natural variation and feedbacks) only start as the pressure builds. So now we see a crack in the dam (the divergence, definite leak). There is also reasonable confidence that there are hidden cracks that have yet to manifest (ocean heat content that is not yet measured).

    ‘fits and starts’ is an interesting way to put it. yes the natural variability can get in the way of the anthropogenic signal. But now we see the divergence and it is pretty clear.

    So there is a lot of pressure behind the dam and more water is coming out the overflows (extra heat that is warming the planet). Unexpected things could happen, but the expected is already happening and it generally quantitative.

    In other words the amount of GHG’s and the general understanding of the sinks, maths, physics are tracking will with the scenario B from Jim Hansen’s model he started in the late 80’s.

    So I think the quantitative assessment is reasonably well established as it now is matching well with the observations.

    While uncertainties linger in the noise, the signal is standing out and waving its arms saying hey, I’m over here, pay attention.

  47. 97
    Ray Ladbury says:

    Bob Sphaerica, First, you have to look at ALL the evidence. There is no way you get simultaneous stratospheric cooling and tropospheric warming without a greenhouse forcing. And increased tropospheric water vapor ain’t gonna give you that.

    Second, one cannot simply posit a mystery forcing and say it will behave like a greenhouse gas without specifying the candidate mechanism. If they were saying the mechanism were increased insolation, then perhaps you would see warmed nights, but it is very unlikely you’d see the seasonal effect (WV persists only on a timescale of days).

    I cannot emphasize this second point enough. I mean ferchrissake, they could posit Martians with heat rays sending in IR photons to exactly mimic greenhouse forcing by CO2. They need to propose a mechanism and see what sort of signature it would give.

    Simply saying, “Well, it could be something else” ain’t science.

  48. 98

    Bit of a sticky wicket, (to quote the British), this WickiLeaks, eh? There’s the issue with releasing classified information, but also there’s the issue of living in a free society, where freedom of speech is a guaranteed right. The cretin who stole all this information should be tried and sent to prison, but Assange is only disseminating what he was handed. Wonder what they would do to him if this were Russia?

  49. 99

    I probably should have included this graph for clarification. It shows the comparative anomaly for winter versus summer, and is the heart of the skeptical science post. It shows that warming prior to 1979 had summers slightly warmer, or at worst intersecting, with winter.

    Then, in 1979, the signal switched, and winters became warmer than summers.

    This is perfectly in keeping with the signal that one would expect for a GHG forcing (after 1979), versus any other forcing (prior to 1979).

    Unfortunately, the roughly 0.4C warming from 1890 to 1940 should have included a strong GHG feedback component as one (notable) part (2/3) of it. If that were the case, then one would think that the summer/winter deviation would not be so high. If it is not the case, then this implies a lack of GHG feedbacks, and so a lower climate sensitivity.

    My problem is not one of proving or disproving attribution. The stratospheric cooling argument is still valid. The lack of change in TSI argument is still valid, etc. It’s just a question of whether or not the “seasonal signature” argument is valid as affirmation of GHG warming (or alternately if the dominance of GHG feedbacks is valid, on the timescales seen within the climate events of this century, given that the GHG signature for such feedbacks appear to be missing in the period from 1890 to 1940).

  50. 100

    Gallagher 98,

    My take on the WikiLeaks fiasco is here: