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Unsettled Science

Filed under: — gavin @ 3 December 2009

Unusually, I’m in complete agreement with a recent headline on the Wall Street Journal op-ed page:

“The Climate Science Isn’t Settled”

The article below is the same mix of innuendo and misrepresentation that its author normally writes, but the headline is correct. The WSJ seems to think that the headline is some terribly important pronouncement that in some way undercuts the scientific consensus on climate change but they are simply using an old rhetorical ‘trick’.

The phrase “the science is settled” is associated almost 100% with contrarian comments on climate and is usually a paraphrase of what ‘some scientists’ are supposed to have said. The reality is that it depends very much on what you are talking about and I have never heard any scientist say this in any general context – at a recent meeting I was at, someone claimed that this had been said by the participants and he was roundly shouted down by the assembled experts.

The reason why no scientist has said this is because they know full well that knowledge about science is not binary – science isn’t either settled or not settled. This is a false and misleading dichotomy. Instead, we know things with varying degrees of confidence – for instance, conservation of energy is pretty well accepted, as is the theory of gravity (despite continuing interest in what happens at very small scales or very high energies) , while the exact nature of dark matter is still unclear. The forced binary distinction implicit in the phrase is designed to misleadingly relegate anything about which there is still uncertainty to the category of completely unknown. i.e. that since we don’t know everything, we know nothing.

In the climate field, there are a number of issues which are no longer subject to fundamental debate in the community. The existence of the greenhouse effect, the increase in CO2 (and other GHGs) over the last hundred years and its human cause, and the fact the planet warmed significantly over the 20th Century are not much in doubt. IPCC described these factors as ‘virtually certain’ or ‘unequivocal’. The attribution of the warming over the last 50 years to human activity is also pretty well established – that is ‘highly likely’ and the anticipation that further warming will continue as CO2 levels continue to rise is a well supported conclusion. To the extent that anyone has said that the scientific debate is over, this is what they are referring to. In answer to colloquial questions like “Is anthropogenic warming real?”, the answer is yes with high confidence.

But no scientists would be scientists if they thought there was nothing left to find out. Think of the science as a large building, with foundations reaching back to the 19th Century and a whole edifice of knowledge built upon them. The community spends most of its time trying to add a brick here or a brick there and slowly adding to the construction. The idea that the ‘science is settled’ is equivalent to stating that the building is complete and that nothing further can be added. Obviously that is false – new bricks (and windows and decoration and interior designs) are being added and argued about all the time. However, while the science may not be settled, we can still tell what kind of building we have and what the overall picture looks like. Arguments over whether a single brick should be blue or yellow don’t change the building from a skyscraper to a mud hut.

The IPCC reports should be required reading for anyone who thinks that scientists think that the ‘science is settled’ – the vast array of uncertainties that are discussed and dissected puts that notion to bed immediately. But what we do have are reasons for concern. As Mike Hulme recently wrote:

[S]cience has clearly revealed that humans are influencing global climate and will continue to do so, but we don’t know the full scale of the risks involved, nor how rapidly they will evolve, nor indeed—with clear insight—the relative roles of all the forcing agents involved at different scales.

The central battlegrounds on which we need to fight out the policy implications of climate change concern matters of risk management, of valuation, and political ideology. We must move the locus of public argumentation here not because the science has somehow been “done” or “is settled”; science will never be either of these things, although it can offer powerful forms of knowledge not available in other ways. It is a false hope to expect science to dispel the fog of uncertainty so that it finally becomes clear exactly what the future holds and what role humans have in causing it.

Dealing with the future always involves dealing with uncertainty – and this is as true with climate as it is with the economy. Science has led to a great deal of well-supported concern that increasing emissions of CO2 (in particular) are posing a substantial risk to human society. Playing rhetorical games in the face of this, while momentarily satisfying for blog commenters, is no answer at all to the real issues we face.

567 Responses to “Unsettled Science”

  1. 401
    Norman says:

    Just when you think that AGW is real and you read the link Gavin posted on the need to homogenize temp data to smooth it, a 6 year-old and his Dad kind of show the opposite conclusion and back it up with reasonable evidence. Link to the 5 minute video.

    http://www.youtube.com/watch?v=F_G_-SdAN04&feature=player_embedded#

    [Response: Don’t get it. Why does repeating the correction for urban biases that is already in the GISTEMP analysis affect anything? And this has nothing to do with homogenisation issues either. – gavin]

  2. 402
    Luke says:

    #386 John Byatt

    Sorry, I dont understand though. This article claims that this research has been peer review in what are some pretty respectable journals… What am I missing here?

  3. 403
    Tilo Reber says:

    Barton: #356
    “BPL: So tell me how cosmic ray irradiation causes clouds to form seven hours later… when the average cumulus cloud, for instance, lasts 20 to 30 minutes.”

    It’s not a one step process Barton. If I remember right, the sequence goes something like this: The cosmic rays create isotopes. The isotopes create aerosols, the aerosols form droplets, the droplets form clouds. Now what do you propose as the connection for the time it takes to create clouds and the time that they last. Are you saying that clouds cannot take longer to create than they last? Why? You obviously have in mind something that you read somewhere. Maybe you could provide me a link so we can discuss more clearly.

    [Response: ions, not isotopes. (they create (a much smaller amount of) isotopes too, but that isn’t the issue here). Read Bart’s post. – gavin]

  4. 404
    Hank Roberts says:

    Luke, you’re wrong–either you’re misreading the Australian or you’re being fooled.
    The Australian mentions two journals — one is Nature, the other is Energy and Environment.

    Some of what Nature publishes is peer-reviewed research. E’n’E

    Nature also publish what’s called a “Letter” — that’s what the Australian is describing.
    Have another look at my earlier reply to you:
    http://www.realclimate.org/index.php/archives/2009/12/unsettled-science/comment-page-8/#comment-148138
    Look at the last link there and read the quotes from the authors of that Letter to Nature.

    Then look at Nature’s description here:
    http://www.nature.com/authors/author_services/how_publish.html and from the links there the details on the various different sorts of article you’ll find. Again, that was a Letter:

    “Letters are short reports of original research focused on an outstanding finding whose importance means that it will be of interest to scientists in other fields”

    So, did you read the PhysOrg quotes from the authors of the Nature Letter? Do you see how the Australian pasted their stock interpretation on the story, but it’s not what the scientists are talking about?

  5. 405
    Tilo Reber says:

    Gavin:#392
    [Response: At different periods in Earth history I guess it would be possible, but for the recent 40 odd years the answer is very clearly no (since there hasn’t been a long term change in GCR over that time). – gavin]

    I’m not following you here. There was definitely a change before that time. A strong rise in solar cycles, and therefore a decrease in GCRs. Since the level changed from the previous level, why can’t the climate (with the oceans as a heat sync) take that 30 or 40 years to catch up to the decreased level of GCRs.

    [Response: Actually, no – there wasn’t definitely a decrease before that time. Dye3 shows a trend in 10Be (a cosmogenic isotope), but that doesn’t show up in South Pole or at NGRIP. And even if there was a rise, you would except the greatest rate of change in the response at the time and a slow relaxation as the ocean adapted. But that is completely the opposite of what was actually observed. – gavin]

  6. 406
    phil c says:

    [Response: It’s called projection. If the contrarians are happy to cheat and manipulate and come up with results according to who is paying them, they assume the mainstream climate science does the same. Except they are wrong. – gavin]

    So, “the contrarians” (including ALL scientists who challenge the ‘consensus’) “cheat and manipulate” , i.e. are frauds

    [Response: No. But there has been a ‘pattern of strange errors’ let us say in a certain class of paper. – gavin]

    Careful, Gavin, I’m sure you wouldn’t imply Kirkby is a cheat but it could easily be read that way.

    A lot of people are going to watch Jasper Kirkby’s lecture and have similar questions to mine. He cannot be dismissed as a crank, he’s a professional physicist and so it is highly unlikely that he would risk throwing away his career by falsifying data etc.

    [Response: I never said he did. However, his reading of the literature is rather uncritical. – gavin]

    Even allowing for a bit of (unconscious) data tweaking here and there his lecture implies an explanation for.

    The Medieval Warm Period
    The Little Ice Age
    Most of the temperature variation through the 20th century
    He includes a role for CO2, albeit less significant.
    and quite a bit more.

    Either this lecture is totally wrong or there is some validity to it.

    If there is validity then not only is the science not settled but it may be missing a key ingredient and yet, people who even question the consensus are labelled deniers, contrarians, flat-earthers etc.

    I suspect that many professional scientists not involved in climate research have gone along with the consensus view because while they were not qualified they naturally assumed that their colleagues in climate science would be working to the same professional standards (which most of them will be).

    However, despite the desire to sweep the CRU leaks/hacks under the carpet, many professional scientists will have been shocked to core by what they have seen and will now be looking much more carefully at the subject in general.

    I expect to see far more main stream scientists starting to challenge the ‘consensus’ view

    [Response: It takes more than correlations to provide ‘explanations’ for climate events. Kirkby is being very selective in what he shows. For instance, he uses one 10Be record (Dye3) that has a trend in the 20th Century to conclude there is a 20th C trend in GCR, but doesn’t note that other 10Be records (NGRIP, South Pole) don’t show the same thing. Similarly, for every record that seems to show a correlation to solar, there are many more that don’t. Note too that the regressions vary wildly in magnitude and sometimes in sign. For sea level he takes one record, but ignores others that don’t fit his thesis as well. His description of the tropical hotspot issue is very simplistic (it is not a function of the greenhouse effect) and out of date. He confuses internal variability and natural forcing etc. It’s all very well to that this is ‘suggestive’ rather than conclusive, but ignoring counter arguments coming from the same literature leaves a misleading impression. And given the history of ‘strange errors’ in this field, he needs to be far more scrupulous if he wants to be taken seriously outside the ABC (Anything-But-Carbon) crew. – gavin]

  7. 407
    Didactylos says:

    Luke, The Australian is fooling you. The article in Nature does not say what they claim it does, and the other article is in a poorly regarded journal (Energy and Environment) and the results are rejected by all the climate scientists I have heard from.

    The Nature paper is discussing climate 33 million years ago. I haven’t looked at the paper myself, but I know that climate then was very different to climate now. The results that the journalist claim simply can’t be derived from such an article.

    This is why you should be very sceptical of secondary sources. You should be doubly sceptical of known biased sources such as The Australian.

  8. 408
    Lawrence Coleman says:

    re:400 Matthew Unfortuantely usually one of the first biological systems to fail under sustained sress conditions is the reproductive system, invertebrates are not different. Matthew what you must understand is if the acididity fell by 1/2 of 1 ph increment and it stayed that way for a long time then gradually species would adapt. The situation here is that with increased rate of CO2 in the air the ocean is forced to sequester a higher rate of CO2 to keep the gradient. Thus the ocean is every day becomming more acidic. So these poor creatures not only have to adapt to current conditions but to keep adapting as the rate of acidification increases. The oceans can only hold so much CO2 however and there is evidence that this process may be slowing down, still by the time that process has stopped completely the seas wont be able to sustain anything anyway. Since the oceans sequester about 1/2 of all the CO2 in ther air that would mean that atmospheric CO2 will have gone well beyond a major tipping point and actually will be increasing CO2 concentration in the atmosphere at twice the current rate. Elevated levels of CO2 do cause plants to grow faster up to a point but it also depends on how much nitrogen there is in the soil to begin with. Low levels of nitrogen compounds in the soil..little or no effect from CO2. Another thing if that was to cause accelerated growth of oceananic flora that would be very dangerous since that process is very finely balanced. Too much algae or seaweed will cause widespread death of fish due to light depletion and oxygen starvation. As you can see everything in nature is perfectely balanced.

  9. 409
    JB, Portland Oregon says:

    Can you elaborate on that youtube video – it’s compelling in a simple, populist way and looks like the kind of thing that spreads (I think “viral” is the phrase du jour). If it were true that only urban temperatures showed increases over last 100 years in the US with respect to nearby rural areas, would that mean anything about global average temperatures in the same time period?

    This seems a classic case of the change in modern information exchange – equal or greater weight given to youtube vs. peer-reviewed research.

  10. 410

    “What do you think of Norm Kalmanovitch’s claim that most of the outgoing radiation that could be absorbed is already absorbed?”

    BPL: It’s completely wrong.

    http://BartonPaulLevenson.com/Saturation.html

  11. 411
    Silk says:

    phil c – Re CO2 vs Cosmic Rays

    There is a very strong body of evidence to suggest that climate sensitivity to CO2 is around 3 degrees. i.e. that every time you double CO2 concentrations in the atmosphere, the temperature goes up 3 degrees.

    Irrespective of what the cosmic ray people come up with, none of that evidence goes away.

    In short, reach 550ppm CO2 and global mean temperature is extremely likely to increase by between 1.5 and 4.5 deg C. And nothing Svensmark or anyone else has done on cosmic rays impacts upon that.

  12. 412
    Ray Ladbury says:

    phil c says, “So, “the contrarians” (including ALL scientists who challenge the ‘consensus’) “cheat and manipulate” , i.e. are frauds…”

    That’s hardly fair. Some of them are stupid. Some are both. John Christy and Spencer are creationists who actually think intelligent design is science.

    Some are contrarians (e.g. Lindzen, Svensmark), who feel their pet theories have gotten short shrift. Unfortunately, this latter category often overpromotes their ideas to unsuspecting lay audiences.

    He then adds, “I expect to see far more main stream scientists starting to challenge the ‘consensus’ view.”

    Ya know, I wouldn’t hold my breath if I were you. It’s about evidence. The climate scientists have it. The denialists don’t.

  13. 413
    phil c says:

    It takes more than correlations to provide ‘explanations’ for climate events.

    But the constant message is the climate has warmed as anthropogenic CO2 has risen – “anyone can see it, only an idiot would deny the link”.
    .
    But apart from this correlation, where is the actual evidence that CO2 is the primary cause of any warming – especially as this warming has happened before.

    and, Kirky presented an explanation – you may not agree but that does not count.

    This is not scientific, but having lived in/around London for over 30 years, if they held ice-fairs on the Thames then it has **seriously** warmed up since then. A lot more than 0.8C and not a drop of anthropogenic CO2 in sight, and I doubt Urban Heating can explain it either.

    There is 0% chance that AGW can explain the LIA (or any earlier historical event) whereas Cosmic ray interactions are possibly correct.

    Every time a problem is identified with AGW such as
    Cooling after 2nd world war
    LIA, MWP
    Lack of (much if any) warming since 2000
    etc.

    Another “epicycle” has to be added to explain it all.
    We need a Copernicus

    I still appreciate the responses Gavin but we have to disagree – I don’t believe CO2 is the real problem. The real problem now is that the public have been told it is. Look at all those people on Climate-Change protests – if you’re wrong, you are going to have a lot of angry people to deal with.

  14. 414

    phil c, the evidence for CO2 causing the observed warming exists in (by now) thousands of papers–check the AR4 bibliography. Needless to say, the sheer volume of research poses a problem for the layman who wishes to evaluate the state of the science. The IPCC actually was created to address this problem (not, as is claimed by the tin-hat brigade, as part of a conspiracy to force you to take the bus.)

    If that’s not working for you for whatever reason, there’s a lot on this very site–try the “start here” in the top header of the page. Weart’s “Discovery of Global Warming” is an often-recommended resource, for very good reason. My favorite, though, is to look at the historical science on the topic. Doing so really builds the context for you, and the papers are relatively easy to understand, since much of the science has become part of our world view since it was originally done.

    Classic global warming science can be accessed here:

    http://wiki.nsdl.org/index.php/PALE:ClassicArticles/GlobalWarming

    Try some of these resources, phil, and I think you’ll come to see that “belief” (your word, in form of the verb “believe”) may not be the best noun to describe the states of mind involved on each side of this debate.

  15. 415
    Jonathan says:

    Please, could you post an article explaining why, with rising CO2 levels, The temperature is in a decline the last 9 years?

    [Response: We did. -gavin]

  16. 416

    oh, and phil, I forgot to mention that your LIA concerns are a logical non sequitur: since significant AGW post-dates the LIA, of course it can’t explain it.

    However, mainstream science can. See:

    http://bartonpaullevenson.com/LeanTSI.html

    (Check the graph at the bottom of the page, and the associated comments–you’ll have to scroll down past the data table.)

  17. 417
    tharanga says:

    phil c, 413:

    If after all this time of reading and posting on climate blogs, you think the connection between CO2 and climate is based on some sort of statistical correlation and not a well-described physical mechanism, I simply don’t know what to say to you.

    Likewise for your other point, which is basically ‘climate scientists think CO2 is the only forcing, ever’. No they don’t.

    It should take all of ten minutes for a newcomer to the topic to see the fallacies in your statements in 413.

  18. 418
    P. Lewis says:

    phil c says

    I expect to see far more main stream scientists starting to challenge the ‘consensus’ view

    Oh yeah! Wrong!

  19. 419
    Completely Fed Up says:

    Philc “But the constant message is the climate has warmed as anthropogenic CO2 has risen – “anyone can see it, only an idiot would deny the link”.”

    And there is more than just that.

    Read the IPCC reports.

  20. 420
    phil c says:

    phil c says, “So, “the contrarians” (including ALL scientists who challenge the ‘consensus’) “cheat and manipulate” , i.e. are frauds…”
    That’s hardly fair. Some of them are stupid. Some are both. John Christy and Spencer are creationists who actually think intelligent design is science.

    My point was that by creating a group called contrarians and saying “they” cheat and manipulate, Gavin could be accused of implying Jasper Kirkby was also a cheat – although I dont think Gavin would.

    Ya know, I wouldn’t hold my breath if I were you. It’s about evidence. The climate scientists have it. The denialists don’t.

    here’s a challenge for you. Watch the lecture then tell me Jasper Kirkby is a “denier”
    and also tell me what he is denying.
    http://seekingalpha.com/article/175641-climategate-revolt-of-the-physicists

  21. 421

    phil: But apart from this correlation, where is the actual evidence that CO2 is the primary cause of any warming

    BPL: Radiation physics.

    I recommend you read Houghton’s “The Physics of Atmospheres” and work the problems.

  22. 422
    Tilo Reber says:

    Gavin: #405
    “[Response: Actually, no – there wasn’t definitely a decrease before that time. Dye3 shows a trend in 10Be (a cosmogenic isotope), but that doesn’t show up in South Pole or at NGRIP. ”

    Okay, I’m assuming that solar cycle strength will be a good inverse proxy for GCRs. And solar cycle strength clearly increased up to roughly 1960. This is shown in the following cart:

    http://2.bp.blogspot.com/__VkzVMn3cHA/SIFs9m3EmII/AAAAAAAAADM/q1Zk0U-n0YI/s1600-h/Sun+Spots.bmp

    Here is a chart from Svalgaard that shows a rise in geomagnetic activity from his starting point to about 1960. Again, I’m assuming that an increase in the geomagnetic index means a decrease in GCRs.

    http://wattsupwiththat.files.wordpress.com/2009/09/ap-bgs-svalgaard.png

    Gavin:
    “And even if there was a rise, you would except the greatest rate of change in the response at the time and a slow relaxation as the ocean adapted.”

    I agree with your conclusion here, but I’m not so sure that it’s not what actually happened. I believe that the network for measuring ocean heat content is post 1960. So I’m not sure what was happening to the heat content prior to that. The surface temperature acceleration from 1978 to 1998 was probably effected by ENSO as shown in this chart.

    http://www.esrl.noaa.gov/psd/people/klaus.wolter/MEI/ts.gif

    It also looks like surface temperature adjustments were mostly biased to increasing the temperature – especially in the second half of the twentieth century. The warming is not nearly as large in the raw data. NCDC has a chart showing the effects of their adjustments over time, but I can’t seem to locate it at the moment. But it does point to a heavy warming bias in the adjustments. On top of that, we have the tree ring proxy divergence from the surface record and we have an IPCC spagetti graph where non of the poxies are able to match the increase in the surface temperature record. I’m not suggesting that poxies are better for measuring temperature than instruments, but given the much smaller increase in the raw data and given the lack of support for the adjusted increase by the proxies, I’m not sure that the acceleration is as large as claimed. Additionally, the relaxation that you are talking about does seem to have happened since 1998 in the surface temps and for about the last 6 or 7 years in ocean heat content.

  23. 423
    Matthew says:

    408, Lawrence Coleman: As you can see everything in nature is perfectely balanced.

    Up till then you were plausible. But everything in nature experiences wild oscillations, and nothing is ever balanced. Predator-prey, Lottka-Volterra and all that. The appearance of balance is an illusion based on observations of isolated bits over short intervals.

    Antibiotics prevented infectious bacteria from reproducing, and extremely effectively at that, allowing the body’s immune system to kill and clear the bacteria. But the bacteria lineages and populations adapted anyway. All of the evidence is in favor of adaptation by random variation and natural selection. The threat is to large animals, but sharks and tuna have survived enormous oscillations in CO2 and temp.

    406, Gavin’s comment: It takes more than correlations to provide ‘explanations’ for climate events

    Glad to hear it. With solar changes, CO2 (H2O, methane, et al) changes, land use changes and possibly unknown changes all occurring at the same time that temperature rose in the late 70s to late 90s, and with all of them having plausible and partially researched mechanisms, there might not be sufficient evidence now to estimate the actual independent forcings of any particular mechanism. All the parameter estimates are highly correlated.

    Global warming “alarmism” is a product of the two-decades long concomitant rise of CO2 and temp after the advent of global cooling “alarmism”. Without the correlation, no one would care, although there was a minor bout of global warming “alarmism” in the 30s.

    410, BPL, thanks for the link.

    399, Gavin’s response: It’s called projection. If the contrarians are happy to cheat and manipulate and come up with results according to who is paying them,. I wish everyone would stay away from the motivational “insights”. Psychoanalysis isn’t well-grounded in research, and there’s lots of money to be made promoting global warming “alarmism”. Right now, for example, businesses in China and India (including coal-fired power plants and steel mills) get lots of money from the EU carbon credits, and Al Gore could lose a fortune if the bottom were to fall out of the carbon credit business. Granted the big oil companies don’t want interference in producing oil, but ADM and others reap huge rewards from govt subsidized biofuels. There are also turbine and PV cell manufacturers in China making huge profits selling to the US.

  24. 424
    Matthew says:

    408, Lawrence Coleman: Too much algae or seaweed will cause widespread death of fish due to light depletion and oxygen starvation.

    Well, light is pretty depleted already except near the surface, and the algae that would benefit from more CO2 would be the photosynthesizing type, such as the varieties used to make biofuel.

  25. 425
    Matthew says:

    389, BPL: BPL: I’ll quantify them for you. The risks of global cooling are zero since global cooling isn’t happening and isn’t going to happen. The risks of global warming are greater than zero and are probably very, very large.

    I view that as a religious statement, like an interpretation of the Revelation of St. John.

    Consider: according to AGW:
    1. we don’t know what caused the Roman warm period;
    2. we don’t know what caused the Roman warm period to end;
    3. we don’t know what caused the Medieval Warm Period;
    4. we don’t know what caused the Medieval Warm Period to end and produce the Little Ice Age;
    5. we don’t know what caused the Little Ice Age to end;
    6. we don’t know what caused the oscillation of warming (1850s-1880s, 1915-1935 appx, 19770-1997 appx) and non-warming (1885-1915 appx, 1940-1977 appx, 1997-2009 appx) (though we have some good estimates of the ENSO, volcanic aerosol, and other aerosol effects for the last few decades, and for a few outstanding epochs earlier);

    Nevertheless, we know for certain by AGW that the warming of 1997-2007 was caused by anthropogenic greenhouse gases, and it will resume at a catastrophic rate, though that might be a few decades in the future yet.

    Whatever “known unknowns” were responsible for 1 – 6 might still be at work, and for all we can tell now they might be more powerful than anthropogenic greenhouse gases. The risk of catastrophic cooling is not zero; if the dominant forcing mechanism for 1-6 was the the solar cycles (of multiple periodicities), and if the sun remains in its current low activity state, then the risk of catastrophic cooling (like the LIA) is substantial.

    Your testimony is as you wrote, but my testimony is that “the science is not settled”.

    410, BPL. That’s a good paper (or at least a good web page.) Can you calculate the net change in the rate of inflowing energy to outgoing energy, assuming a doubling of anthropogenic greenhouse gases, averaged over a year, based on your analysis? Because of gravity, even most CO2 is within 2km of the earth’s surface, but the effect of AGG is at higher altitudes. If AGGs doubled, what would be the increase in AGG mass above 2 km?

    I repeat, that’s a significant improvement on Hessinghigh, who I gather is the source for Kalmanovitch.

  26. 426
    Geoff Wexler says:

    399
    “[Response: It’s called projection. If the contrarians are happy to cheat and manipulate and come up with results according to who is paying them, they assume the mainstream climate science does the same. Except they are wrong. – gavin]”

    The various stunts usually combine both mechanisms. For example the Swindle opened with a bold assertion “You are being told lies” and then proceeded to manipulate everything including the witnesses, the graphs and even the calendar by labelling ~ 1975 “NOW” so to remove all the recent warming.

    In the case of the Emails stunt, the procedure has been a variation on this theme. Unlike the Swindle, this was not necessarily a single ‘production’ but that is of little importance. The method was first to assume fraud so as to motivate a campaign of harrassment, then burgle (or exploit a burglary) then cheat to manufacture the evidence which had failed to turn up.

    One example of the latter is the circulation of emails to which ‘helpful’ interpretations have been added at the top. Another is ‘over the top’ allegations made on UK TV by Inhofe and Morano. I hope these and many other examples have been recorded by the various pro-science bloggers. They can then be reminded of their errors later , but I doubt if it will stop the practice any more than the arrival of more CO2 and more warming.

  27. 427
    David B. Benson says:

    phil c (413) — I urge reading climatologist W.F. Ruddimans popular “Plows, Plagues and Petroleum” regarding the anthropomorhic part of LIA. To go further, explore “1491”.

  28. 428
    Silk says:

    “But the constant message is the climate has warmed as anthropogenic CO2 has risen – “anyone can see it, only an idiot would deny the link”.”

    Wrong. We didn’t say “Temperature has risen. CO2 has risen. Therefore the latter caused the former.”

    We (or rather, the scientists, not me) said, back in the 50s, 60s, 70s and 80s “If CO2 keeps rising temperature increased”. And lo! In 1992 the countries of the world said this was a problem. And the 90s were the warmest decade on record, and the 00s warmer than that.

    Scientist warns of problem. Problem is observed. Nothing to see here.

    “But apart from this correlation, where is the actual evidence that CO2 is the primary cause of any warming – especially as this warming has happened before.”

    Have you /READ/ anything on this site? Try “Start here”.

    “There is 0% chance that AGW can explain the LIA (or any earlier historical event) whereas Cosmic ray interactions are possibly correct.”

    Irrelevant. The knife in the corpse can’t explain the death of my great-grandfather, therefore it can be the cause of death. Logic fail.

    “Every time a problem is identified with AGW such as
    Cooling after 2nd world war LIA, MWP
    Lack of (much if any) warming since 2000
    etc.”

    There is no lack of warming since 2000. How much warming were you expecting? With confidence intervals, please.

    LIA, MWP, 40s are not ‘problems with AGW’.

    “I don’t believe CO2 is the real problem.”

    You are wrong.

    “The real problem now is that the public have been told it is.”

    You are wrong

    “Look at all those people on Climate-Change protests – if you’re wrong, you are going to have a lot of angry people to deal with.”

    And if /you/ are wrong, millions will die prematurely due to famine and disease. The global economy will contract significantly. Development gains will be rolled back. Refugees will flood into Europe and Canada. US and Australia will be a dustbowl.

    And you are wrong.

    So Copenhagen had better get it right.

  29. 429
    Hank Roberts says:

    > Because of gravity, even most CO2 is within 2km of the
    > earth’s surface, but the effect of AGG is at higher f
    > altitudes. If AGGs doubled, what would be the increase
    > in AGG mass above 2 km?

    You should start with the “Start Here” button at the top of the page, then the first link under Science in the right sidebar. Or, you should stop asking what you may imagine is a trick question, if you already have read the basics.

    When you post questions like that under a common name like “Matthew” you poison the well for the next kid along with the same name, who may be mistaken for you.

    Get a real name and ask for actual help understanding this stuff and people here, including other ordinary readers like me, will make a sincere effort to help. Don’t waste time and attention.

  30. 430
    phil c says:

    I’ve tried every which way to get Gavin (or anyone else) to come flat out and say Jasper Kirkby is wrong and if so why is he wrong

    So, I have to assume that Gavin accepts that there is a chance (albeit small) that the idea Kirkby presents may be right – care to step in here Gavin?

    We are told to trust the scientists

    In one corner we have the AGW team.
    In the other we have Jasper Kirkby etc.

    All very professional highly educated and qualified to speak on their subjects. But they don’t agree.

    Unless Kirkby etc are definitely wrong and can be shown to be wrong, until that possibility is eliminated then there is a chance that AGW is wrong.

    I accept it may be a very small possibility but we are about to begin spending $X trillion dollars – don’t you think it would be a good idea to be really, really sure?

    I know how strong you feel “your” evidence is but here’s a question to anyone here…

    Is Kirkby wrong and if so why?

    [Response: But why do you think that scientists need to agree on every little thing? They don’t. Kirkby might well think that CLOUD will find something interesting and that it will be relevant to climate. I don’t think that likely, but who knows, I could be wrong! That’s how we get ahead – different scientists with different theories predict different outcomes of an experiment. The experiment is done, and one or none of them is vindicated. We learn something. But even if Kirkby is right, it doesn’t mean that the physics of CO2 is wrong – he isn’t testing that at all. – gavin]

  31. 431
    Ray Ladbury says:

    Phil C.,

    Your approach reveals a vast misunderstanding of how science and scientists operate. First, CLOUD in no way impacts what we already know about CO2. The two effects are not in any way coupled. It could reveal something interesting and leave models largely unchanged except for that aspect.

    Second, why should one prejudge an experimental outcome before doing the experiment? Climate science is about a lot more than global warming–that is just the aspect of it that is going to severely impact our lives, regardless of how CLOUD comes out.

  32. 432
    phil c says:

    [Response: But why do you think that scientists need to agree on every little thing? They don’t. Kirkby might well think that CLOUD will find something interesting and that it will be relevant to climate. I don’t think that likely, but who knows, I could be wrong! That’s how we get ahead – different scientists with different theories predict different outcomes of an experiment. The experiment is done, and one or none of them is vindicated. We learn something. But even if Kirby is right, it doesn’t mean that the physics of CO2 is wrong – he isn’t testing that at all. – gavin]

    Well this “little thing” that you don’t agree on could turn out to be rather important

    So we spend a few trillion and create havoc around the world. Then it turns out CLOUD shows (somehow) that CO2 is not that significant, it’s OK “we learn(t) something”

    Come on Gavin, I saw you on the TV the other day and was no swaying there – full on confidence. Would you go back on CNN and let them know that “hey, who knows, I could be wrong!”

    [Response: Of course. Do you think I’m the pope or something? But you are still confused – there is no way that CLOUD is going to show anything about the radiative effect of CO2. Nothing. Nada. Zip. – gavin]

  33. 433
    phil c says:

    Agreed the physics of CO2 is not going to change.
    But the Earth’s atmosphere is not a test tube and its response to a bit more CO2 may be far more subtle than anyone currently expects. Much stranger things have turned out to be true.

  34. 434
    Martin Vermeer says:

    phil c #430,

    I accept it may be a very small possibility but we are about to
    begin spending $X trillion dollars – don’t you think it would be a
    good idea to be really, really sure?

    The usual ‘don’t bet unless you’re certain’ fallacy, ignoring that we are
    betting already, for high stakes. Like, we’re betting the future of
    our civilization
    on the ‘null model’, i.e., nothing bad is going to
    happen to us under business as usual — a ‘model’ that both violates
    century-old text book physics, and contradicts the observations from
    multiple independent sources. Its only redeeming grace is that it gives
    a warm and fuzzy feeling…

    We need to learn to make better bets, quickly.

  35. 435
    phil c says:

    Your approach reveals a vast misunderstanding of how science and scientists operate. First, CLOUD in no way impacts what we already know about CO2. The two effects are not in any way coupled. It could reveal something interesting and leave models largely unchanged except for that aspect.
    Second, why should one prejudge an experimental outcome before doing the experiment? Climate science is about a lot more than global warming–that is just the aspect of it that is going to severely impact our lives, regardless of how CLOUD comes out.
    Comment by Ray Ladbury — 10 December 2009 @ 7:06 PM

    consider this as a thought experiment

    You work in laboratory and establish the physics of CO2
    You extrapolate your knowledge up to the earth’s atmosphere do the maths and make the following prediction

    X-Tons CO2 will give Y degrees warming
    then we put X-Tons up there and the temperature indeed goes up Y degrees
    So, we have “proved” AGW

    except, someone comes along and shows that actually
    another mechanism (possibly clouds) can be shown to have caused Z degrees of warming.

    But the total amount of warming is still Y degrees.
    So, all things being equal, this can only mean that
    X-Tons CO2 actually only caused Y-Z degrees of the total warming.

    This does not mean that the physics of CO2 has to be revised. All that stuff worked out in the 19th century etc is still perfectly valid. What it would mean is that our understanding of the atmosphere’s response to additional CO2 was wrong – and I think this is possible

    This is why the outcome of CLOUD is significant because it could show CO2 was less significant, and maybe not such a threat in terms of Global Warming

    No one is trying to re-write the laws of CO2 physics, but it would mean that the atmosphere was a more subtle than you think it is.

    [Response: It will have no impact on the attribution of climate change whatsoever because there isn’t a recent trend in GCR. Z is very close to zero. – gavin]

  36. 436
    Dave says:

    You may be correct that not scienctist has ever claimed that the science is 100% settled. Politicians on the other hand make this claim on an incredibly regular basis. I am yet to ever see a politician publicly rebuffed for making this false claim.

  37. 437
    Matthew says:

    425, Matthew: the warming of 1997-2007

    That’s probably a Freudian slip. I meant the warming of 1977-1997.

  38. 438
    Sandra Kay says:

    I tried posting this in the newer comments….maybe you are no longer accepting challenges to your “interpretation” of the “trick”?

    Anyone have anything to say about this analysis by Mr. McIntyre? Seems pretty straightforward how they “hid the decline” and why they needed to do it (excellent reconstruction of emails along with real time events)

    [edit]

    http://climateaudit.org/2009/12/10/ipcc-and-the-trick/

    [Response: They are confused. The mismatch that they were concerned with is seen in the first figure where the Briffa and Jones reconstructions are substantially higher and lower than Mann’s through the LIA (1500 – 1900AD). Note the line “Keith’s series .. differs in large part in exactly the opposite direction that Phil’s does from ours. This is the problem we all picked up on… “. It has nothing to do with the post 1960 issue. The full email is a much clearer read than McIntyre’s cherry-picking. – gavin]

  39. 439
    Pekka Kostamo says:

    As a non-scientist, I found this paper very informative on climate science practice (as well as on other computationally intensive sciences):

    Engineering the Software for Understanding Climate Change
    Steve M. Easterbrook, Timothy C. Johns
    http://www.cs.toronto.edu/~sme/papers/2008/Easterbrook-Johns-2008.pdf

    It outlines in an approachable way the workings of one of the major centers of climate reasearch. There are several other centers, of course, each having its own structures and methods.

    In the end it boils down to a simple choice: You either trust or you don’t trust the process and its built-in quality controls and validation sub-systems. You can not re-run the experiments without access to a major management and science team and (possibly) months of time at a supercomputing center. Talk of “releasing the code and data” is very much idle and ignorant. Just a theory without practical application. Some of the models have been available on-line for years but apparently nobody has done anything useful with them.

    These software systems are the basis of hundreds of scientific papers each year both by the center staff and by outside users, each paper with its unique configuration of a million line Fortran code, the code evolving through some 5 new releases annually. The output is then verified in peer review and subsequent science.

    There are more than ten research centers doing the same job. Fundamentally they exist to try and generate a competition advantage for the national governments funding them. Being first with the best science brings benefits socially, economically and in terms of national security. Assuming, of course, that the scientific discoveries are not ignored.

  40. 440
    Matthew says:

    438, Gavin’s comment. “The full email” (http://www.eastangliaemails.com/emails.php?eid=136) is definitely worth the read. If you follow the links in the email, you can find the graphs of the reconstructions, like this one:
    (1) http://www.ncdc.noaa.gov/paleo/ei/ei_nodendro.html

    (note: there are many such that are discussed)

    And you can find a graph of the tree-ring reconstructions (up to 1960) with the 20th century instrumentally recorded temperatures grafted in:
    (2) http://www.ncdc.noaa.gov/paleo/ei/ei_reconsa.html

    These are evidently the graphs that were in the MBH98 paper (that’s what Mann calls it in the email) that was critiqued by the Wegman report. Note, there was a lot of work done by the authors, not all of which could possibly be published, and the technical discussions are worth reading. You have to admire Mann et al’s work, and the scholarly discussion in the email. It takes a great deal of time to analyse all those spatial time series with their non-overlapping sampling times, not to mention all the time it takes to perform the laboratory work and collect the samples.

    That said, this does seem to be Mann’s “trick” that Phil Jones used to “hide the decline”. Isn’t it?

    It is curious that a technique considered unreliable enough to reconstruct the recent past (this is the famous “divergence”) was considered reliable enough to reconstruct the distant past. You would have to know for certain what caused the divergence, and that nothing that large had happened before.

  41. 441

    Thanks for the link to the full email, Gavin–I think. (I’d been ignoring anything except the denialist “talking points” since the emails, after all, were supposed to be private.)

    However, I must nominate Chris Folland’s statement for “Hacked Email Least Likely To Appear In A Skeptic Blog.”

    That statement: “We want the truth.”

  42. 442
    Matthew says:

    439, Pekka Kostamo: each paper with its unique configuration of a million line Fortran code,

    One thing I have been glad to learn from this episode is that Fortran is still a living language.

  43. 443
    phil c says:

    [Response: It will have no impact on the attribution of climate change whatsoever because there isn’t a recent trend in GCR. Z is very close to zero. – gavin]

    I quote from a quote about Kirkby taken from http://www.canada.com/story.html?id=975f250d-ca5d-4f40-b687-a1672ed1f684

    … the sun and cosmic rays “will probably be able to account for somewhere between a half and the whole of the increase in the Earth’s temperature that we have seen in the last century.”

    Which reads to me that he feels “Z” might be quite significant which would be interesting – to say the least.

    But then again, he couldn’t possibly be right – could he?

    [Response: People can make any claim they like. But if they want to convince other scientists they have to show some convincing evidence to support it. I see no evidence in his presentation or other work that would lead to Z being anything like that large. – gavin]

  44. 444
    Thimbles says:

    I figure I’d post this here since it’s I have uncertainty about my calculations. Based on here
    http://www.realclimate.org/index.php/archives/2005/04/water-vapour-feedback-or-forcing/
    you claim that “CO2 alone makes up between 9 and 26%” of the greenhouse effect. I was wondering if
    A) that was a measure of uncertainty about the percentage or if that was a range given the variability of earth regions in time.
    (when I was asked this question I thought of it as a range since areas such as the polar icecaps have less water vapor in the air due to condensation and would therefore have a lower GW effect, a percentage water vapor GW effect, and a higher percentage CO2 effect. But I could easily be mistaken.)

    [Response: No, it’s the range you get if you don’t go into the overlaps. If you do and attribute them properly, the answer you get is just under 20% (clouds 25%, water vapour 50%). – gavin]

    B) if you could express rising CO2’s rising contribution temperature by taking its percentage of GW (9% to 26%) multiplying it by the total GW effect (+33°) and multiplying that by the percentage of the rise in CO2 since preindustrial period (387ppm – 280ppm / 280ppm)? Is this a productive calculation or am I missing a bunch of stuff and therefore the resulting calculation is garbage? Is it productive to use such a calculation to picture the potential of double in preindustrial CO2?

    [Response: It’s not that easy unfortunately because the feedbacks caused by changes in CO2 also change the water vapour, temperature structure and clouds and so the calculations change. – gavin]

  45. 445
    phil c says:

    [Response: Of course. Do you think I’m the pope or something? But you are still confused – there is no way that CLOUD is going to show anything about the radiative effect of CO2. Nothing. Nada. Zip. – gavin]

    No you are not the pope – but I found this on Wikipedia
    “But you are still confused there is no way that Galileo is going to show us anything about celestial bodies. Nothing. Nada. Zip. – Pope Urban] ”

    Although you are safe to say the physics of CO2 is fixed (I agree) you are on shakier ground when you say that its role in the atmosphere is fully understood.

    If CLOUD does turn out to “account for somewhere between a half and the whole of the increase in the Earth’s temperature that we have seen in the last century” (Kirkby’s words not mine) then, unfortunately for you, it would show the effect of CO2 In the overall atmosphere could not be the same as you currently think.

    You cannot end up with both AGW and CLOUD somehow explaining the majority of the warming.

    Gavin, I really appreciate the fact that you’ve taken the time to post replies – and although you may be right I still see a possibility that other work may show you are seriously wrong.

    thanks again, I wont post anything more (unless a reply is too tempting)

    [Response: But CLOUD can’t possibly show anything of the sort. Kirbky is talking about attribution of climate change – something which is not calculated in smog chamber, however expensive. – gavin]

  46. 446

    Matthew: Because of gravity, even most CO2 is within 2km of the earth’s surface

    BPL: Huh? CO2 is well mixed all the way up through the stratosphere.

    [Response: Well-mixed refers to concentration, not mass. But Matthew is confused, pressure at 2km is about 800 hPa, and so only about one fifth of the CO2 is in the lower 2km. – gavin]

  47. 447

    Phil C,

    Let’s put things in perspective here. CLOUD is a smog chamber study, not at all unimportant, but staking the future of the earth and the decision to spend (or not spend) billions of dollars on one smog chamber study seems not warranted.

    CLOUD will not be the last word on the cosmic ray – climate question, even though it’s an important and noteworthy experiment. Its results will still have to be combined with what’s already known about the various topics at hand (see http://www.realclimate.org/index.php/archives/2009/04/aerosol-effects-and-climate-part-ii-the-role-of-nucleation-and-cosmic-rays/) and withstand the test of time, e.g. through replication efforts with different means. Its results may add something to the puzzle of what we know about climate, but it won’t replace everything we know.

    You may have seen the paper describing the initial results from the CERN experiment: http://www.atmos-chem-phys-discuss.net/9/18235/2009/acpd-9-18235-2009.html The results are rather inconclusive one could say: Some experiments suggest a role of ion induced nucleation; many more don’t. And it’s still a long journey to bridge the gap between aerosol nucleation and climate effects via cloud activation.

    Science doesn’t work by providing absolute proof. It works by searching for the most likely explanation. Waiting for absolute proof is like waiting for Godot. And since you consider the stakes of spending lots of money while perhaps (not very likely according to the science) being wrong, would you also consider the reverse: Not dealing with the problem, when it later turns out the science was right (most likely), or wrong in the other direction: understating the seriousness of the problem (not very likely, but perhaps on equal footing as the first outcome)?

  48. 448
    Silk says:

    Phil C – This is getting very boring.

    Let me make it simple.

    If CLOUD proves that changes in GCR cause temperature changes on earth, THIS IS NO WAY IMPACTS on the statement

    “If CO2 reaches 550ppm or greater, global mean temperature will increase by 1.5 to 4.5 degrees (95% confidence)”

    THERE IS NO LINK between CLOUD and this statement.

    None.

    Zero.

    Zip.

    CO2 will reach 550ppm or higher this century, unless we intervene reduce emissions.

    Therefore there is only (from a policy perspective) one question worth asking. “Is the cost of reducing emissions greater or less than the cost of not doing so, and letting temperature increase?”

    The body of evidence suggests inaction is more damaging that action.

    Therefore, the policymakers should act.

    The interesting questions are then, “what are the best actions to take?”, “how can they best be implemented (in a way that maxmises impact at minimum cost and disruption)?” and “how much action is needed?”

    You diversion into GCR is completely meaningless. And rather dull.

  49. 449
    Matthew says:

    446, Gavin: Well-mixed refers to concentration, not mass. But Matthew is confused, pressure at 2km is about 800 hPa, and so only about one fifth of the CO2 is in the lower 2km.

    That is interesting. What is the altitude above which there is only 20% of the CO2 total?

    [Response: ~200 hPa level, which is 12 km or so up. – gavin]

    448, Silk: Therefore there is only (from a policy perspective) one question worth asking. “Is the cost of reducing emissions greater or less than the cost of not doing so, and letting temperature increase?”

    That might deserve its own thread. For one economic opinion, a dollar of prevention might be worth 2 cents of care. That’s a paraphrase of Bjorn Lomborg. This is analogous to a variation on Pascal’s wager: if you accepted Pascal’s logic, would you bet on the Allah of Mohammed or the God of the Old Testament? To get really far-fetched, the analysis of periodicities of past past glaciations suggest that we are past the expected end of the current inter-glacial epoch (a detail that was mentioned in the global cooling alarmism of the 70s.) In light of the observed decline of solar activity, global cooling should not be assigned a “known” probability of 0.

  50. 450