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This Week

Filed under: — mike @ 4 May 2007 - (Türkçe)

There are a few minor items this week worthy of mention:

1. The CO2 rise. Who dunnit?

Here at RealClimate, we have been (naively, apparently) operating under the assumption that climate change contrarians had long ago moved on from the untenable position that humans are not even responsible for the observed increase in CO2 concentrations over the past two centuries. The dubious paper by Ernst Beck we commented on the other day indicates that there is indeed still a rear guard attack being waged. As if to drive the point home further, pundit Alexander Cockburn, known generally for his progressive views, has perplexingly disputed the existence of any link between CO2 emissions and rising CO2 concentrations in the atmosphere in a screed he penned this week for the online journal “Counterpunch” (also printed in The Nation). It’s hard to know where to start, since his piece is so over the top and gets just about everything so thoroughly wrong, it’s almost comical. So we’ll just hit the low points: (a) Cockburn claims that there is zero empirical evidence that anthropogenic production of CO2 is making any measurable contribution to the world’s present warming trend, despite the fact that not even such strident climate change contrarians as Pat Michaels dispute that there is a measurable influence of anthropogenic greenhouse gases on global temperature. Plus there’s all the empirical evidence of course (see the new IPCC report). (b) Going further, Cockburn brazenly opines that ‘it is impossible to assert that the increase in atmospheric CO2 stems from human burning of fossil fuels’ despite the fact that there is an isotopic smoking gun for this connection. He then (c) fails to understand that water vapor is a feedback not a forcing, and citing ‘expert’ Dr. Martin Hertzberg, quite remarkably states that ‘It is the warming of the earth that is causing the increase of carbon dioxide and not the reverse.’ Never mind that isotopic evidence proves otherwise. Upon what evidence does he base this assertion?

Since no anti-global warming op-ed these days is complete without it, Cockburn (d) resorts to the usual misrepresentation of lag/lead relationships between CO2 and temperatures during glacial/interglacial cycles as if they disprove the causal relationship between greenhouse gas concentrations and surface temperatures (see our most recent debunking of this favorite contrarian talking point here). Oh dear.

2. The other (Glenn) Beck–Even Worse!

CNN gave their resident shock-jock Glenn Beck a forum for spreading more disinformation on global warming in an hour-long segment entitled Exposed: The Climate of Fear (see also this discussion by “Media Matters”). We could pick apart his (rather thin) arguments, which constitute the usual cocktail of long debunked contrarian talking points. Suffice it to say, however, that the moment a rhetorician invokes Hitler, Nazi Germany, and Eugenics, it is the moment they are no longer worthy of being listened to (cf Godwin’s Law of usenet debates). We don’t seem to be alone in our opinion here. Beck’s performance earned him the dubious title of “worst person in the world” from analyst Keith Olbermann.

However, there was one amusing moment: Beck asked Christopher ‘Incorrect’ Horner what the key thing to google was that would show that Al Gore was wrong. Horner suggested the lag between CO2 and temperature in the ice cores. Of course, if you do Google that, the first hit is the RealClimate debunking of the issue. Thanks!

3. Nature’s new blog

Nature has started a new blog called “Climate Feedback”, which says of itself ‘Climate Feedback is a blog hosted by Nature Reports: Climate Change to facilitate lively and informative discussion on the science and wider implications of global warming. The blog aims to be an informal forum for debate and commentary on climate science in our journals and others, in the news, and in the world at large.’

We wish it well, remembering their welcome for RealClimate, though early reviews based on the first few posts are decidedly mixed.

280 Responses to “This Week”

  1. 251
    Steve Hemphill says:

    Re #250,

    Follow the link. [edited--please retain a civil tone.] Ghg’s heat up Earth’s surface, and convection, along with latent heat of evaporation, moves some of the heat upward into the mid troposphere where the water vapor condenses, releasing the heat up, away from the surface. This is aided by the fact that moister air is lighter.

    If you still don’t get it “I will [edited] not respond further to your … comments.

  2. 252
    Steve Hemphill says:

    I guess the civil tone part doesn’t apply to Paul?

    [it applies to everyone! Folks: any further comments that do not maintain a civil tone will not be screened through. -moderator]

  3. 253
    Hank Roberts says:

    Steve appeared to write
    >> Re #234,
    >> That just violates basic thermodynamics.

    What is the actual statement you believe violates thermodynamics?
    Possibly the numbers have changed.

  4. 254
    Steve Bloom says:

    Re #249 (fredrik): Regarding a good explanation for stratospheric cooling, look at this subsequent RC post and the links thereto.

  5. 255
    Donald B Hagler says:

    Back to basics, please. Cockburn stated that “there is zero empirical evidence” for AGW. RC of May 4 cites “the new IPCC report” in refutation. It would help to have the specific IPCC link to such evidence, if available. Thanks.

  6. 256
    Donald B Hagler says:

    Comment #255 is intended for Gavin (or Mike, who posted Real Climate’s May 4 original entry on Cockburn), whichever of the two might be in the best postition to support Real Climate’s refutation of Alexander Cockburn’s assertion that there is no empirical evidence for AGW. This assertion is not original with Cockburn–I’ve seen it earlier in several other places unrelated to Cockburn and it is gaining credence and momentum. So if there is a link to specific evidence countering it, it would be helpful.

  7. 257
    Tony Weddle says:

    A recent article by Kjell Aleklett makes an important point. That IPCC scenarios assume an unlimited supply of fossil fuels, so that each scenario can be simulated without any regard to the limited nature of such resources. Indeed, even the most optimistic assessment of fossil fuel resources (the BP Statistical Review) only sees half, or even less, than that necessary for the worst case scenario.

    Does anyone know if, indeed, climate modellers do assume unlimited fossil fuel resources? If so, why?


  8. 258
    Dan says:

    re: 256. Repeating an assertion does not mean it is “gaining credence” or “momentum”. Furthermore, the latest IPCC report (which is based on peer-reviewed science, not assertions) provides plenty of empirical evidence. It is linked from this site.

  9. 259
    Nigel Williams says:

    Donald B Hagler, if I might be presumptious; you might find a bit of useful info at:

    but if getting your head right into that doesn’t do the trick, read RC from go to woa and keep coming back

    I think this RC article by Stefan Rahmstorf is tops,

    as it helps us understand how IPCC *has to be* conservative to ensure its credibility, but the potential for more extreme outcomes is soberingly real:

    Then after absorbing that; if you still have any denialist twinges, go stand on the beach and pretend you’re King Canute.

    Remember for us common folk its not so much a who-dunit anymore, but a whatll-we-do-now at the individual level!

    Im not being cheeky, but getting your head around what matters here does involve a bit of study. Its worth it, for the children, at least.

    Kind regards


  10. 260
    Hank Roberts says:

    Tony, that article about ‘running out of coal sooner’ is among several on the site; they’re talking about running out of coal at current economic costs and prices and talking about the worst case projections for climate change — the ‘different planet’ scenarios — being impossible. They’re making the “it’s too late to change” argument there in a slightly different fashion.
    One of the links from there points to this:

    The comments there point to this: (“posting there by Stoneleigh on the carrying capacity of the world’s population)

    I didn’t read the thread, just looked at the chart. It doesn’t match what I’ve read everywhere else, can’t evaluate it.

    Even if we’ve burned up half the coal on the planet to date and it’s peaked like oil, we can’t burn the other half in the current century without dismal consequences.

    Yes, we’ve been using far more energy than is available from natural biogeochemical cycles —- that’s just the flip side of the excess carbon dioxide we’re putting into the air beyond what natural biogeochemical cycles can retrieve.

  11. 261
    Timothy Chase says:

    Re: 256

    “Chapter 2: Changes in Atmospheric Constituents and in Radiative Forcing” simply by itself has over sixteen pages of references – peer-reviewed aticles that it cites. I haven’t performed an exact count, but I believe this would put it in the neighborhood of 650. And that is just one chapter.

  12. 262
    William Astley says:

    Is the sun moving towards a Maunder Minimum? Implications to climate?

    A) The following is a 2003 Prediction, based on solar observations and a Physical Model that the Sun is moving towards a Maunder Minimum (See link for details.)

    The sun is currently not following the expected solar cycle behaviour. The NASA solar cycle prediction group are planning to meet every 3 months to re-evaluate the cycle 24 prediction based on new data.….34.0603S

    “Long-range (few years to decades) solar activity prediction techniques vary greatly in their methods. They range from examining planetary orbits, to spectral analyses (e.g. Fourier, wavelet and spectral analyses), to artificial intelligence methods, to simply using general statistical techniques. Rather than concentrate on statistical/mathematical/numerical methods, we discuss a class of methods which appears to have a “physical basis.” Not only does it have a physical basis, but this basis is rooted in both “basic” physics (dynamo theory), but also solar physics (Babcock dynamo theory). The class we discuss is referred to as “precursor methods,”… My colleagues and I have developed some understanding for how these methods work and have expanded the prediction methods using “solar dynamo precursor” methods,… This has led to better monitoring of the Sun’s dynamo fields and is leading to more accurate prediction techniques….

    …The surprising result of these long-range predictions is a rapid decline in solar activity, starting with cycle #24. If this trend continues, we may see the Sun heading towards a “Maunder” type of solar activity minimum – an extensive period of reduced levels of solar activity.

    B) The following is a 2004 paper that predicts the sun is heading towards a Maunder Minimum based on an analysis of the paleo record of solar activity.…605L..81B

    We have examined the long-term trends in the solar variability that can be deduced from some indirect data and from optical records. We analyzed the radiocarbon measurements for the last 4500 years, based on dendrochronology, the Schove series for the last 1700 years, based on auroral records, and the Hoyt-Schatten series of group sunspot numbers. Focusing on periodicities near one and two centuries, which most likely have a solar origin, we conclude that the present epoch is at the onset of an upcoming local minimum in the long-term solar variability. There are some clues that the next minimum will be less deep than the Maunder minimum, but ultimately the relative depth between these two minima will be indicative of the amplitude change of the quasi-two-century solar cycle.

  13. 263
    Ray Ladbury says:

    On the basis of less than 1 solar cycle’s data to determine that we are going to enter another Maunder Minimum: NOW THAT IS ALARMIST. Slight deviations from the 7-yr max, 4-yr min are common. I’ve seen nothing that would lead me to believe we’re seeing anything other than variability within the normal range of the solar cycle.

  14. 264
    John Mashey says:

    re: #262

    I don’t know whether to wish harder for:
    a) Another Maunder Minimum, soon, to slow the rise a bit.

    b) Not, as a) might well convince people there was nothing to worry about.

  15. 265
    tamino says:

    When I see papers which proclaim, on the basis of proxy data “which most likely have a solar origin,” that “the present epoch is at the onset of an upcoming local minimum in the long-term solar variability,” the red light on my skeptimeter flashes. When I further see predictions based on “quasi-cycles,” I know that the authors may have fallen prey to the too-common tendency to see genuine periodicities where there are only characteristic timescales, or simply random fluctuations. Believe me, it happens all the time.

    I’ve looked at a lot of statistical analysis of “solar cycles” as well as the statistical analysis of climate data. I find the climate analyses very solid, and the solar-cycle analyses very flabby.

    It’s certainly possible that there are long-period solar cycles; it’s even possible that we’re headed for another “Maunder-like” minimum. But the evidence is very sketchy. The evidence for AGW is solid as a rock.

  16. 266
    Donald B Hagler says:

    Re: 259 and 261 Thanks Nigel and Timothy for taking the time to note your suggestions. They look promising.

  17. 267
    William Astley says:

    In reply to comment #263 “On the basis of less than 1 solar cycle’s data to determine that we are going to enter another Maunder Minimum: NOW THAT IS ALARMIST.”

    As there is no modern instrumentation record of how and how quickly the sun moves from a normal cycle to Maunder state, there are definitely unknowns concerning what could or will take place. Based on my understanding of the mechanism, the cycle change would be abrupt. Solar cycle interruption as opposed to a cycle slow down. If the cycle change fails to occur or is gradual and has no or a minor affect on climate, I would be surprised. I would expect the cycle change to be complete in roughly 4 years. I could of course be incorrect.

  18. 268
    Tony Weddle says:

    Re: 260. Thanks for the comment. Hank. One reason I posted was that the argument took what many regard as a very optimistic (depending on one’s point of view) assessment of fossil fuel resources – the BP review – and still can’t come up the amount of CO2 needed for the worst case scenarios. James Hansen and Pushker Kharecha also came up with a similar study, though more cautious on coal. It’s linked to from here:

    Implications of “Peak Oil” for Atmospheric CO2 and Climate

    But I’m still curious as to whether the IPCC scenarios do assume unlimited fossil fuel resources.


  19. 269
    Nigel Goddard says:

    Alexander Cockburn has an unfootnoted response over at Counterpunch, also behind the subscriber firewall at The Nation. He asserts the reducing C13/C12 ratio could just as easily be due to oxidation of plant sources of carbon other than fossil fuels. And also could be due to action of cold oceans which he says prefer to absorb one isotope over another. Since he’s not a scientist and doesn’t cite scientific sources there, it’s hard to evaluate. Can anyone who knows the science comment on his assertions?

  20. 270
    tamino says:

    Re: #267 (William Astley)

    As there is no modern instrumentation record of how and how quickly the sun moves from a normal cycle to Maunder state, there are definitely unknowns concerning what could or will take place.

    I believe that was the point of #263. The uncertainties are great enough that predictions of an imminent Maunder minimum are an interesting speculation, but nothing like a reliable forecast.

  21. 271
    Hank Roberts says:

    It’s very sad. Specific attack on RC included.
    He attempts to source some of what he believes. Boiled down, amateur reader version:

    —-begin excerpt—-
    … primitive rhetorical pandybats…
    … affinity to those who insist the Holocaust never took place.
    … the consensus of “scientists”
    … coterie include very few real climatologists or atmospheric physicists.
    … plenty who do not accept the greenhousers’ propositions.
    … intimidated into silence by the pressures of grants, tenure and kindred academic garottes.
    … University of Virginia’s Pat Michaels
    … Dr Fred Goldberg
    … the probable culprit, Professor Bert Bolin, a politically driven Swede
    … 1995 IPCC … Executive Summary … stated that humans have influenced the climate
    … Fredrik Seitz … Wall Street Journal …
    … day and night or seasonal variations in photosynthesis cause clearly visible swings in the curve, the 30 percent drop between 1929 and 1932 caused not a ripple.
    …the naïve and scientifically silly assumption that the only way that plant-based carbon can get into the atmosphere is by people burning fuels …
    … low-C13 carbon most certainly would have been released massively into the atmosphere over the course of the world’s warming trend since 1850, when the Little Ice Age ended.
    … I was offline, in Russia, flying thither over the Arctic and thus able to make a direct review of the ice cap.
    —–end excerpt——

    So he’s discovered an Arctic ice cap, and a dramatic change in the temperature of the oceans since 1850 — both of which are claims open to attempts at confirmation by others. And he believes he can see day and night variations in CO2 in the chart.

    He believes the temperature change he believes he discovered in the ocean would cause release of C12 and C13 to explain the C14 depletion.
    No mention how long ocean circulation takes to turn over. No sources given for the belief the ocean has warmed.

    He apparently doesn’t believe the Arrhenius and subsequent work, or he’d worry that if all the CO2 since 1850 came out of the ocean already, that there will be a whole lot more coming out in the subsequent centuries. Logically he may believe a Venus-type runaway is implicit in this, but it’s hard to tell.

    He doesn’t say where he believes the fossil fuel carbon went. No numbers.

    For the rest I’d refer to the biogeochemical cycle, rate of ocean circulation, the work documented in the AIP history section on C14, and

    Happy Birthday, Rachel Carson.

  22. 272
    Phil G says:

    First I want to say I appreciate to opportunity to make a comment and ask a question.

    I am an AGW skeptic, but not a cynic. I can be convinced.

    When I search RC on Dr. Zbigniew Jaworowski I am very surprised to find only two hits. One regarding his refusal to make a bet, and one in Alexi’s response to another post.

    Dr. Jaworowski’s claim is that the CO2 levels taken from ice cores are inaccurate because the ice cores are not a closed system, etc., would appear to be an important point. It does not appear to be discussed anywhere on RC that I can see. Can you point me to the discussion of the issues Jaworowski raises? Or, explain why he is wrong?

    Thank you

  23. 273
    Hank Roberts says:

    This may help:

    “… Jaworowski makes several specific assertions…. Each and every one …mistaken.
    He makes sweeping accusations … unsupported by any evidence, direct or indirect.
    These … reveal a deep misconception of the state of climate research …
    … where to start. Hereâ��s a map: ”

  24. 274
    Hank Roberts says:

    More on Cockburn, and his response to repeated requests for his sources:

  25. 275
    Warren Hoskins says:

    Not having scientific training, yet deeply troubled by Cockburn’s assertions, I have been chewing on them. The statement that global CO2 emissions scaled back so severely during the Great Depression has started to trouble me. If the emissions did not scale back as much as he baldly asserts, one of Cockburns legs is out from under him. I find no report (disclosure: hasty ill-informed search) that seems to source his assertion of quantities of CO2 being emitted annually starting in 1928. And I have a hard time believing it anyway. Sure, the early 1930s was a time America went into an industrial slump–but how does that match up with the rise of industrial production in the Soviet Union and Japan? And maybe industrial use of coal plummeted, but I recall much mention in recent times about the importance of coal and firewood for American families during the Depression–both for heating and cooking, and as income sources. So is Cockburn accurate about the scaling back of CO2 emissions? Or just very sure of himself and weak on the facts?

  26. 276
  27. 277
    John Mashey says:

    re: #275
    Warren: not having scientific training, how about math & statistics, and skepticism towards such? If you’ve haven’t read books like the following, you owe it to yourself to buy most (or all) of these, which will be one of the bet investments you can make for your ability to sort sense from nonsense.
    You can get the first 3 for a total of less than $50 from Amazon,

    0) Un-Spun finding facts in a world of disinformation, Brooks jackson, Kathleen Hall Jamieson (2007)

    1) How to Lie with Statistics, Darrell Huff & Irving Geiss 1954

    2) Damned Lies and Statistics: Untangling Numbers from the media, Politicians, and Activists, Joel Best (2001).

    3) How to Lie with Charts, Gerald Everette Jones (2006)

    and maybe
    4) How to Lie With Maps, Mark Monier, H. J de Blij

    and of course:
    5) “The Visual Display of Quantitative Information:, Edward Tufte, is classic.

    However, I wouldn’t lose sleep over what Cockburn says, and if you read only book 0), you will find some examples.

    1) I believe his assertion that CO2 production dropped is correct, although I couldn’t find the exact numbers. I did find:

    which had numbers supposed to be from CDIAC.
    They’re slightly different, but close enough, and it makes historical sense.

    2) (Basic, disquieting, but relatively minor): Cockburn either can’t do simple arithmetic, or else is following a well-known trick. In Cockburn’s piece:

    He says a plummet from 1.17 to .88 is a 30% drop.
    Actually (1.17-.88)/1.17 = .29/1.17 = 24.8%.
    [.29/.88 = 33%, but that's not the right math; using the wrong denominator is a classic trick.]

    However, Cockburn has also pulled another classic trick. He picked the highest peak and the lowest dip, which maximize the difference. If you instead do a simple 4-year moving average, it’s less.

    3) Of course, no references are given for anything. (This is a red flag.) When it comes to time-series, be very wary of choice of starting and ending dates, especially when somebody picks a very short period.

    That makes it hard to analyze, but even if we know nothing about the relevant science, we can still think about simple math.
    Let’s phrase his assertion as:
    X = tonnage of CO2 emitted
    Y = concentration of CO2 increase
    and Y ~ X, i.e., if X rises or drops, then so should Y, in proportion.

    You’ve focused on X, and what he says there sounds OK, but of course, exactly how do we know? These are estimates, since there was no giant CO2 meter running. But let’s assume they’re OK.

    But how about Y? He says it is a smooth rising line.
    He mentions Mauna Loa, which offers records down to *daily* resolution, i.e., this is very good data, and on a yearly basis it is smooth. Of course, it has *nothing* to do with 1929… but it sounds good.
    He says, ice core records were used pre-1958.

    Now, do you know: what’s the resolution of ice-core records (not Mauna Loa), i.e., how sure are you that a meaurement is for 1929 or 1930? Or mabye you can tell the difference between 1930 and 1935
    How much uncertainty is there in the measured CO2 ppm?

    Since he didn’t give sources, it’s hard to know anything, but fortunately:

    Google: co2 law dome gives us:,
    which says outright:

    “The Law Dome ice core CO2 records show major growth in atmospheric CO2 levels over the industrial period, except during 1935-1945 A.D. when levels stabilized or decreased slightly.”
    Of course, Cockburn didn’t mention 1935, did he? Was he looking at a graph that just had 1929-1933?

    and here is their data:

    If you look carefully at the columns “Mean Air Age” and CO2 Mixing ratio, in the first 3 pieces are the data sets for the individual ice-cores.
    Let’s suppose we know nothing about ice-cores, but just look at the numbers:
    a) For mean Air Age, the years don’t go 1928, 1929, 1930…
    they go:
    DE08: 1924, 1932 1938
    DE08-2: 1832, 1934, 1940 (1832 is not a typo)
    DSS: 1926, 1929, 1936

    Why is that? Well, the date resolution is +/-2 years (from the paper), i.e., they’re pretty sure that any of those dates lies in a 4-year range, but the intervals they give are sometimes 6 or 8 years apart, adn they think the CO2 ppm resolution is .2ppm. This makes it rather difficult to be really sure about an effect that would lag the emissions drop, which only asteda few years. It’s like trying to compute the hourly temperature, given that you only read the thermometer a few times/day. You might geta rainshower that drops the temparature for a while in between measurements.

    In the next table, they give you a year-by-year CO2 number. How do they do that? (That’s like doing hourly temperatures). Well, they do 20-year-smoothing, using original data 4-6 years apart. With 20-year smoothing, you’re not going to see much effect from a 25% (peak) drop for a couple years. So, if Cockburn was looking a yearly chart, OF COURSE IT’S SMOOTH. it can’t be anything else, and this is a scientist’s way of showing that we really don’t know what’s going on every year, even though we trust the overall numbers.

    1) There is a clear flattening/dip in ice-core CO2 that lags the emissions dip.

    2) The flattening happens shortly after the period Cockburn cites. What a funny coincidence!

    3) The ice-core resolution and 20-year smoothing *guarantee* that when you generate a year-by-year chart, it will be fairly smooth, and cannot show moderate effects that last a couple years.

    4) Cockburn is either almost totally innumerate or trying to fool people, or both…

    Please go read those books and help protect yourself from nonsense.

  28. 278

    [[Not having scientific training, yet deeply troubled by Cockburn's assertions, I have been chewing on them. The statement that global CO2 emissions scaled back so severely during the Great Depression has started to trouble me. If the emissions did not scale back as much as he baldly asserts, one of Cockburns legs is out from under him. I find no report (disclosure: hasty ill-informed search) that seems to source his assertion of quantities of CO2 being emitted annually starting in 1928. And I have a hard time believing it anyway. Sure, the early 1930s was a time America went into an industrial slump--but how does that match up with the rise of industrial production in the Soviet Union and Japan? And maybe industrial use of coal plummeted, but I recall much mention in recent times about the importance of coal and firewood for American families during the Depression--both for heating and cooking, and as income sources. So is Cockburn accurate about the scaling back of CO2 emissions? Or just very sure of himself and weak on the facts? ]]

    Cockburn is making the tacit assumption — which is grossly incorrect — that the ambient level of CO2 in the atmosphere is directly proportionate to the amount being burned by the United States. But the amount being burned only affects the change in the CO2 level, not the total amount. His 1933 burn of 0.9 gigatons of carbon was half absorbed by the natural sinks (mostly the ocean), leaving, say, 0.5 GtC. But the amount of CO2 in the atmosphere at the time was about 600 GtC. Therefore, the amount burned would be about a 0.1% increase — not a decrease — in the total level.

    How could adding more CO2 to the air possibly result in a decrease of CO2 in the air? If you think it through, Cockburn’s contention — CO2 in the air should have shown a big drop when the US burned a lot less carbon — is completely batty.

  29. 279

    I should add to the above that John Mashey’s statistical discussion is very well done — concise and to the point. The way he nails Cockburn’s statistical illiteracy is lovely. There are annual time series for CO2 before 1959, but they are not anywhere near as reliable as the Mauna Loa data from 1959 and later. We can be very sure of the average CO2 level for 1900-1950, less sure for 1930-1940, and not sure at all for 1933. An average is almost always more certain than an individual measurement.

  30. 280
    Ray Ladbury says:

    Warren, beware true believers, be they from the right or the left. Usually they are people who start from the answer they believe they already know and work backwards. Man in general is not a rational animal, but a rationalizing. Any fool can lie with statistics. What takes skill is using them to tell the truth as John Mashey has done.

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