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Why the continued interest?

Filed under: — rasmus @ 9 October 2009

I believe the idea that galactic cosmic rays (GCR) play a role for the present global warming is unlikely to fade soon, despite a growing number of scientific arguments that normally would falsify a hypothesis and lay it dead (see links here and here). Despite all the arguments against the role of GCR, there was a solicited talk about ‘cosmoclimatology’ at the European Meteorological Society’s (EMS) annual meeting in Toulouse. Henrik Svensmark is further invited by the Norwegian Academy of Science and Letters (NASL) to provide an introduction to their seminar on climate. So why is the GCR-hypothesis still perceived as an interesting explanation?

My impression from the solicited talk, is that the confidence in the GCR hypothesis now rests on two points that were made explicit in the presentation, and that we have not adequately addressed here. So, here they are:

Point I: When I asked Svensmark why he presented a curve describing low cloud-cover from the ISCCP – used for correlation study with GCR (link) – that differed from the curves presented at the ISCCP web site (link), he informed me that he used a corrected version that has been published. Nevertheless, the ‘correction’ of the curve is controversial, and the ISCCP team is clearly not convinced, despite the likelihood of instrumental degradation.

Good practice would then be to present all the curves that cannot be ruled out because of errors. When asked why he didn’t present the other cures too, he said that he only wanted to show the one curve. Not a very convincing answer, and not very reassuring.

Point II involves a ‘remarkable’ correlation, meant to demonstrate a link between high GCR flux and cold conditions. This analysis is based on a comparison between band-pass filtered ice-rafted debris from iceberg drifts (Bond, 2001) and Carbon-14 (a cosmogenic isotope) over the last 12,000 years (e.g. after the most recent ice age).

The relationship between temperature and drifting icebergs, however, is complicated and not so straight forward. Icebergs are formed when chunks of ice break off glaciers and icesheets – a process known as ‘calving’.

On the one hand, icesheets and glaciers grow when the accumulation of precipitation at below freezing temperatures (snow) exceeds the summertime melting. Very low temperatures, tend to be associated with low precipitation, however. One the other hand, iceberg calving does not require very low temperatures (as long as the ice is present), but is favoured by reduced friction at the base of ice caps, resulting in a faster flow towards the sea. Melt water can lubricate the ice sheets and hence affect the ice flow.

Once the icesheets have calved and produced icebergs, they will drift according to the winds and ocean currents. The most influential ocean currents for iceberg drift in the North Atlantic include the East Greenland Current EGC), which follows the east coast of Greenland and flows from northeast to southwest, the West Greenland current (WGC) into the Labrador Sea, and the Labrador current (LC), a coastal current following along the perimeter of the Labrador sea basin in an anti-clockwise fashion.

North Atlantic ocean current systems Many of the cores used to study the ice-rafted debris were from locations away from these currents. It is not clear whether anomalous cold conditions produced more southerly winds and ocean currents. However, many of the core locations are associated with a surface flow from the south in the present climate, so it is possible that the icebergs transported by the EGC, WGC, and LC end up in the North Atlantic current. One explanation is that the icebergs got caught in the warm currents from the south, and melted on their way north, but that does not necessary imply cold conditions in that region, as these warm ocean currents provide a heat transport and the melting of icebergs suggest higher temperatures.

Cold conditions favour the formation of sea-ice, which have very different characteristics to icebergs. Sea-ice forms when the sea surface freezes, and can affect the ocean circulation through their effect on salinity. However, sea-ice does not create debris of rocks and minerals, as the icebergs do when the bottom of the sliding icesheets scrape the rocks.

It is plausible that very cold conditions can produce thick sea-ice that will lock icebergs in place near their sources in the Labrador sea and along the east coast of Greenland, but seasonal variations in the sea-ice may also imply open water in the summer. Nevertheless, very cold conditions may not necessarily favour the production of icebergs, as freezing temperatures will prevent the formation of melt water acting as lubrication and the accumulation of ice is expected to be less due to lower precipitation.

In summary, the ‘remarkable’ correlation does not seem to support the hypothesis that high flux of GCR produces a very cold climate. The question is rather whether the ocean and atmospheric circulation were influenced by the level of solar activity and associated changes in the total solar irradiation (TSI) – without involving GCR. After all, GCR is affected by the level of solar activity through its influence of the inter-planetary magnetic field, and anti-correlated with the sunspots.

When taken in the context of the global warming, there are other problematic issues such as the lack of trend in GCR (here and here), stronger warming during nighttime than daytime, large unknowns regarding the physical mechanisms involved in the growth of ultra-small molecule clusters to much larger cloud condensation nuclei (here and here), and questionable data handling and statistical analysis (here). In addition, it is difficult to statistically distinguish between the apparent response to solar forcing in the observations and GCM which do not take GCRs into account (link to a recent paper by Gavin and myself), implying that GCRs are not needed to explain past global temperature trends.

So what makes the GCR-hypothesis so convincing that warrants a solicited talk at the EMS annual meeting and an invited presentation at the NASL? Is the support based on the attention in media, or does it have a scientific basis?

I want a response from the community still supporting the GCR hypothesis, explaining why they find it convincing after all these misgivings. The spirit of science is about discussing different ideas and challenge unconvincing points of view. So far, I feel that many of these issues have gone unheeded outside the climate research community. Perhaps an improved dialogue between various research communities can help resolving these issues – the counter-arguments and GCR hypothesis represent a paradox that should be sorted out if the science is to progress. Either the supporters of the GCR hypothesis should convincingly explain why these misgivings are unfounded or irrelevant, or the GCR hypothesis should be buried. However, I feel that there is a lack of dialogue and willingness to listen, so I think that progress is not likely to happen regarding a commonly accepted solution on the GCR hypothesis.

Update: According to a recent (October 16) news relsease from the International Ice Charting Working Group (IICWG), over 1,200 icebergs drifted into the trans-Atlantic shipping lanes in 2009, making the iceberg season in the North Atlantic the eleventh most severe since the tragic loss of the RMS Titanic in 1912.

P.S. So far in 2009, three articles have been published in the arXhive on GCR and clouds (here, here, here). It is possible that such articles are more accessible to communities other than climate research, and hence enhances the awareness about the controversy surrounding the GCR-hypothesis.


506 Responses to “Why the continued interest?”

  1. 401
    Rene says:

    The notion that science can get shaped by its funders

    “389 Patrick 027 says:
    Duh. Details? Who funded the study that suggests energy is still conserved in a closed system….”

    It’s a question of an overall bias rather than a detailed control over each and every scientist and project. All funders have objectives, and will tend to select scientists that seem to share those objectives, and projects that show promise of fulfilling them.

    And it makes a great deal of difference how much of a bearing an idea has on a funder’s objectives. A project that is orthogonal to a funder’s objectives – no matter how radical – is less likely to be canned than one that actively undermines them. The idea that energy is conserved in a closed system, for example, would bother neither a funder eager to prove AGW, nor one eager to disprove it.

    “392 Mark says:
    I wonder if Rene thinks that money is sooo powerful it can change reality?…it doesn’t matter what your work comes up with, eventually people will find out.”

    Money can’t change reality, but it can certainly change perceptions of it. And so, in the courthouse that is science, the more money that is put into promoting an idea, the greater its chances of being accepted (other things being equal).
    And ‘eventually’ can be a long time, the actual length of time being related to the amount by which your funder outspends his opposite number.

    [Response: Your idea is brilliant – except that it is completely impervious to any input from objective reality. Look up the grants funded by NSF in climate science and demonstrate this ‘obvious’ correlation you hyothesise. Evidence remember is what distinguishes science from mere rhetoric. – gavin]

  2. 402
    CM says:

    Rene #387, no, “the notion that science can get shaped by its funders” was not at issue. See dhogaza’s #357, excerpting from Taylor’s #356. That funding sources *can* influence research outcomes is a truism. It’s not much to discuss unless you have an argument that specific research *is* so biased.

  3. 403
    MG says:

    Mark: Don’t get me wrong here. I do in fact believe that CO2 has a positive radiative forcing on the Earth. However, I take issue with your comment on the “monumental correlation of CO2″ that “must hit (me) with the blinding light of the divine,” and not only because I am an atheist :) The tight correlation between temperature and CO2 only occurs for the CO2 impoverished period of the recent past. This is for two reasons. First of all, this is because most of the correlation is caused by temperature, a fact that even most AGW-friendly climatologists agree with. Secondly, changes in CO2 are important to climate when concentrations are as low as they are now. If you go back further, to periods with much higher, and likely almost saturating, levels of CO2, then the correlation is worse. To top it all off, during the period of anthropogenically-induced warming (ie., post-industrial), the correlation between temperature and CO2 is actually not that impressive, because the scale allows us to resolve some of the ‘natural variability’ within the climate system, allowing (for example) cooling to be seen for a couple of decades preceding the 1970’s and some would argue the same for the 2002-2008 period. The cause of these variations is complex (atmospheric and oceanic circulation, solar intensity, volcanism etc.), and I personally find these variations to be more interesting than the overall upward trend that is likely caused by CO2. It’s not because I don’t believe “all the mathematics” that I think controversial papers are perfect keynote talks at conferences (though I have met reasonably well-known climate scientists who seem to know how to run the models much more effectively than how to make them). My concern is that the vociferous reaction toward anyone with an off-message theory smacks of agenda and political bias.

  4. 404

    Peter Taylor:

    there then develops a psychological disincentive to change the models – it is human nature – not conspiracy but blindspot and groupthink – and I am an intelligent, scientifically literate person with some experience of the use of models that are rather similar to the climate models and suffer from a huge level of prior commitment and developed vested interests, both political and financial – not to accept this is also denialist and very naive.

    Apparently you have never read the extensive climatological literature. Almost all of the discussion of the models in peer-reviewed science journals is over WAYS TO CHANGE THEM. Climatologists are constantly seeking better parameterizations, better constants, better algorithms. The models today are not the models of the ’60s, or even the models of five years ago. They are constantly being improved, updated, and rewritten by a fraternity of thousands of scientists around the world.

    You really don’t know what you’re talking about. But ignorance is curable. Start reading the journals, for God’s sake! And maybe get a basic grounding in the subject. You might start with Henderson-Sellers’s “A Climate Modeling Primer” (1985).

  5. 405
    Rene says:

    The notion that science can get shaped by its funders

    “Gavin: Your idea is … completely impervious to any input from objective reality…Look up [actual] grants funded…and demonstrate this ‘obvious’ correlation you hypothesise”

    We are probably not able to meaningfully measure the state of a funder’s or a funded scientist’s intentions, as easily as we can measure the temperature. But this is no reason to take as an implicit working assumption, the opposite, highly unintuitive notion, that funding does not influence science.

    [Response: Ah-ha… So since this theory is impossible to test, it must be true! And you wonder why I’m sceptical…. – gavin]

    “CM : That funding sources *can* influence research outcomes is a truism. It’s not much to discuss unless you have an argument that specific research *is* so biased.”

    The basic argument is that any funding of anything is done to advance the funder’s objectives. Science is no different to anything else in this respect. And where the emerging ideas have large implications for the welfare of the funder, assumptions of sustained impartiality strain credibility.

  6. 406
    Mark says:

    “But ignorance is curable.”

    Not when the ignorant don’t want curing.

  7. 407
    Mark says:

    “I do in fact believe that CO2 has a positive radiative forcing on the Earth.”

    Aye, a very weak statement there.

    “The tight correlation between temperature and CO2 only occurs for the CO2 impoverished period of the recent past”

    And over which past did we develop and mutate into humans? Our plants into potatoes, rice, wheat and so on?

    It’s also been lower in the past than now.

    “This is for two reasons. First of all, this is because most of the correlation is caused by temperature, a fact that even most AGW-friendly climatologists agree with”

    Nope, the effect of CO2 causes temperature rises. The CAUSATION is CO2. The correlation proves the causation.

    “Secondly, changes in CO2 are important to climate when concentrations are as low as they are now.”

    And why do you want the jurrasic plants out there? We can’t eat them.

    And this meme you have invented here is strawman pure and simple. How does the CO2 being poor and impoverished now make the correlation and causative effects irrelevant?

    They don’t.

    “If you go back further, to periods with much higher, and likely almost saturating, levels of CO2″

    CO2 is saturated at the peak bands in the atmosphere now. If you mean “cannot hold more CO2″ then it’s never been anywhere near saturated.

    “To top it all off, during the period of anthropogenically-induced warming (ie., post-industrial), the correlation between temperature and CO2 is actually not that impressive,”

    ” because the scale allows us to resolve some of the ‘natural variability’ within the climate system”

    The first doesn’t follow from the second.

    Just because you put a “because” in there doesn’t mean the following reason is anything to do with the effect you precede it with.

    In this case, it doesn’t.

    “The cause of these variations is complex (atmospheric and oceanic circulation, solar intensity, volcanism etc.)”

    Variations in what? weather? Yes.

    In climate? No. It’s 74% due to CO2.

    “My concern is that the vociferous reaction toward anyone with an off-message theory smacks of agenda and political bias.”

    Neither I nor anyone here can be held to blame for your paranoia and unwarranted connections.

    The vociferous reaction is because they are talking tosh. The tosh they talk has been the same tosh talked by thousands of other mewling voices trying to grab the last few days of eden before they die. And after 40 years of it, we’re sick fed up of it.

    Also have you ever read any of the reaction of anyone on WUWT against the surfacestations work? Or Greenman’s work? Or here on this site?

    Just because you have no clue but want to be considered to have one doesn’t mean you can justify a persecution complex.

    There isn’t always two sides to an argument. Sometimes one side is just plain wrong.

  8. 408
    Hank Roberts says:

    > periods with much higher, and likely almost saturating
    (‘saturation’ was long since debunked; who do you trust on this?)

    > levels of CO2
    The PETM is the classic counterexample. Got one that fits your claim?

    > ‘natural variability’… cooling … for a couple of decades
    > preceding the 1970’s
    High anthropogenic aerosols up to 1970 from coal plants–‘natural’?
    Clean Air Act restrictions on aerosols–‘natural’?
    Measurable, yes; documented, yes; natural, arguably, but not meaningfully.

    > and some would argue
    Citation needed

    > My concern is that the vociferous reaction toward anyone with an
    > off-message theory smacks of agenda and political bias.
    Agreed. Pay attention to the science, read the first hand journal articles, and cite your sources when you state what you believe to be facts.

  9. 409
    Mark says:

    “Money can’t change reality, but it can certainly change perceptions of it.”

    No it can’t. It can make you justify avoiding the perception of reality to be tested, but that doesn’t stop someone else having a look.

    And then all that money spent bribing that one person is for nothing.

    So you’d have to bribe everyone else too.

    And when someone finds out that, they’ll ask for more, because not only is there the truth being hidden, but there’s the bribing to be hidden too.

    Then one of the previously bribed hears about it and wants a bigger cut.

    But now you’ve spent a LOT of money on a lot of people. If you don’t pay them what they demand, they’ll say what’s happening and all that much larger amount of money will have been spent for naught.

    And if climate science were being bribed, all it would take is ONE of those scientists to be bribed more by the oil industry to show evidence of the bribing.

    After all, that’s how they catch blackmailers in the real world, and this IS blackmail, even if it’s bribery.

    And because these are government funded agencies bribing all these hundreds of thousands of scientists, the money has to be accounted for. And every new scientist that enters the field (for the bribes, one presumes, rather than the science) is another one to bribe.

    Government spending is pretty easy to account for. If much of it goes to bribes, then it’s obvious. If not much goes to bribes, why are scientists taking it?

    If that person was moral then they may reject the bribery. And again the entire edifice of bribes fall down.

    Meanwhile the oil industry can just come up with repeatable experiments for the REAL science.

    But they don’t do they.

    They have scores of different incompatible reasons for what’s going on and nothing to explain what IS incontrovertibly known.

    And they post on blogs or paid-for sites like Hearland Institute.

    And all the blackmailers have to be bribed to keep quiet. And all the accountants. And all the people who work on the “black projects”. All the people who know that they aren’t getting the money they’ve been said in the accounting reports need bribing. And bribing after retirement too.

    How monumental must the conspiracy be? How expensive?

    How unlikely.

  10. 410
    Mark says:

    PS MG despite having it pointed out to you so very bluntly, you still haven’t said why your position holds despite having nothing explaining why CO2 isn’t having the effect the maths and science baldly says it does.

  11. 411
    Ray Ladbury says:

    MG, the correlation with CO2 concentration is actually pretty good:

    http://www.bartonpaullevenson.com/Correlation.html

    Yes, the variability is an interesting subject in itself–but that is not where the threat comes from.

  12. 412
    Phil. Felton says:

    Mark says:
    20 October 2009 at 8:31 AM
    “If you go back further, to periods with much higher, and likely almost saturating, levels of CO2″

    CO2 is saturated at the peak bands in the atmosphere now. If you mean “cannot hold more CO2″ then it’s never been anywhere near saturated.

    IR absorption is not saturated now see for example the result of doubling [CO2] from current levels:

    http://i302.photobucket.com/albums/nn107/Sprintstar400/CO2spectra.gif

  13. 413
    chris says:

    re #43

    MG, the broad correlation between atmospheric CO2 and climate regimes in the deep past is pretty robust right through the last ~ 500 million years:

    This subject has recently been reviewed:

    D.L. Royer (2006) “CO2-forced climate thresholds during the Phanerozoic” Geochim. Cosmochim. Acta 70, 5665-5675.

    https://wesfiles.wesleyan.edu/home/droyer/web/PhanCO2(GCA).pdf

    Even more recent studies supplement the information in Royers compilation and cover additional periods with new data sets right through the past several hundreds of millions of years:

    R.E. Came, J.M. Eiler, J. Veizer et al (2007) “Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era” Nature 449, 198-202

    W. M. Kurschner et al (2008) “The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of the terrestrial ecosystem”Proc. Natl. Acad. Sci. USA 105, 499-453.

    D. L. Royer (2008) “Linkages between CO2, climate, and evolution in deep time” Proc. Natl Acad. Sci. USA 105, 407-408

    Zachos JC (2008) “An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics” Nature 451, 279-283.

    Doney SC et al (2007) “Carbon and climate system coupling on timescales from the Precambrian to the Anthropocene” Ann. Rev. Environ. Resources 32, 31-66.

    Horton DE et al (2007) “Orbital and CO2 forcing of late Paleozoic continental ice sheets” Geophys. Res. Lett. L19708 (Oct. 11 2007).

    B. J. Fletcher et al. (2008) “Atmospheric carbon dioxide linked with Mesozoic and early Cenozoic climate change” Nature Geoscience 1, 43-48.

    etc…etc..

  14. 414
    chris says:

    whoops, my post just above is in response to MG’s post #403

  15. 415
    Hank Roberts says:

    > and likely
    NOT
    > almost saturating

    http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/

    If you don’t have time to read the science, at least look at the picture:
    http://www.realclimate.org/images/CO2Abs.jpg

  16. 416
    Mark says:

    “IR absorption is not saturated now see for example the result of doubling [CO2] from current levels:

    http://i302.photobucket.com/albums/nn107/Sprintstar400/CO2spectra.gif

    Can’t go to the link, but optical depth of the earth’s atmosphere at the peak bands of CO2 absorption is significantly over 1.

    I.e. you can’t see the earth’s surface from space at those wavelengths.

    I.e, saturated.

  17. 417
    Rene says:

    The notion that science can get shaped by its funders

    …We are probably not able to meaningfully measure the state of a funder’s or a funded scientist’s intentions, as easily as we can measure the temperature. But this is no reason to take as an implicit working assumption, the opposite, highly unintuitive notion, that funding does not influence science.

    #405 Gavin Ah-ha… So since this theory is impossible to test, it must be true! And you wonder why I’m sceptical….

    Ah c’mon! Gavin, I’m not saying anything like that. Admitting that this is not science, I’m merely saying it fits our basic understanding of how people generally think and act. Far better than the alternative theory – ie that funders do not seek to further their goals when allocating funds. A theory just as unscientific and untestable, at least as deserving of scepticism.

    [Response: No. It simply fits your prejudices about how organisations behave. I’ve been in dozens of review panels and been involved in many funding decisions and what you describe has *never* played a role in those decisions. People have been funded based on how interesting their idea is, how likely it is they will be able to do what they claim and (occasionally) how much they have done already. People’s political outlook or what the anticipated results would show just doesn’t get a look in. Unlike you, I have real experience and data on this, and the list of NSF funded proposals to look at, and the basic fact is that there is absolutely no evidence to support your claim. Thus, I am entitled to no longer give it the equal weighting in the true and false stakes than its converse. Bayesian reasoning in action folks… – gavin]

  18. 418
    Martin Vermeer says:

    Gavin, you’re coming down too hard on poor Rene. He just has a different prior

  19. 419
    Patrick 027 says:

    The most climatologically relevant saturation or lack thereof is with regards to changes in net LW flux at the tropopause. When opacity is great enough, all you can see from the tropopause is other layers of air with pretty much the same temperature, so there is almost no net LW flux and very little room to affect it further with more opacity increases.

    I think CO2 is saturated or nearly so between about 14 and 16 microns (hence, the brightness temperature as seen from space is nearly flat over that interval in spite of CO2 opacity fluctuation, except for the peaks in brightness temperature due to larger stratospheric opacity.

    Of course, even at those wavelengths, there is always room for more upper atmospheric cooling – first everything above the tropopause (thus contributing to the tendency for tropopause level shifting), and then when that is too opaque, just the mesosphere and so forth.

    If the tropopause could shift upward to keep up with opacity changes (were it not for the pressure and temperature dependent line broadenning and temperature dependent line-strength, this would require halving the pressure at the tropopause, cutting the mass of the air above in half, for a doubling of CO2), the range of saturated wavelengths would never actually change, but the tropopause doesn’t shift upward that much, so the wavelength interval of saturation widens with increasing CO2 – but the wavelength interval exceeding any significant opacity tends to do the same, because of a generally exponential decay of optical thickness going away from 15 microns (the smaller-scale texture of the spectrum breaks up the wavelength intervals that exceed a given opacity level, so that the edges of any such interval essentially has fuzzy edges – but the width of that fuzz tends not to change (to a first approximation) even as it shifts outward from 15 microns). So after enough CO2 is there to saturate the central part of the absorption band, the width of the band that exceeds a given level of significant opacity through a given layer of air with significant temperature variation, etc, tends to increase in proportion to the logarithm of CO2 concentration – and because the blackbody radiant intensity varies slowly enough over wavelength in comparison to the wavelength shifts being considered, the radiative forcing tends to increase in proportion to the shifting of the edges of the wavelength intervals, and thus with the logarithm of CO2 concentration (the temperature variation with height also affects this – except for polar regions, and perhaps after sufficient reduction of meridional temperature gradients, the lapse rate of the troposphere will generally decrease with greater temperature; however, the temperature difference between the surface and tropopause cand remain the same or increase as the the tropopause level height increases (presumably it increases or increases more for greenhouse effect warming more than for solar forced warming, since the later warms the stratosphere as well). Clouds and water vapor also affect the potential for CO2 forcing as well. If a point were reached where the upper troposphere were completely filled with cirrus, that would drastically cut the potential for additional greenhouse-forced warming, although by itself would be a huge positive feedback to warming up to that point. If cloud fractional area within each layer of air defined relative to the tropopause remained similar, this would not so much alter the potential for additional forcing by greenhouse gases, barring realignments of clouds among different vertical levels or relative to temperature and humidity variations, etc. (and the upward shift in clouds would be a positive LW feedback, while the addition of more cloud area farther below the tropopause (due to increasing depth of the troposphere) would have a negative SW feedback, and there would be some negative SW feedback from higher cloud tops as their albedo effects would be less reduced by absorption from gases above them than they otherwise would given the changes in those gases). As the width of significant CO2 effect widens, it would eventually run into the water vapor absorption bands

    (there is some overlap now, but the overlap effect at the tropopause level is not as big as near the surface because water vapor is concentrated near the surface, so CO2 opacity effectively sits on top of the water vapor where water vapor opacity is not too large. But water vapor opacity gets larger going into longer wavelengths from the CO2 band, and into shorter wavelengths past about 8 microns. (the ‘atmospheric window’, the interval from about 8 microns to about 12 microns, sandwiched between large water vapor and large CO2 opacity, and interupted by a narrow band of ozone absorption, does have some partial absorption by water vapor, and it fills in at higher temperatures with the same relative humidity, essentially bringing net LW cooling of the surface to near zero, requiring an increase in convective cooling except in so far as solar heating of the surface is reduced by water vapor and clouds (if that happens) – but this is only in the lowest layers of the troposphere; the window would still exist for radiation from within the troposphere to escape.)
    —-
    Since an increasing greenhouse effect tends to cool the stratosphere, conceivably the tropopause level itself would also cool, and so, even given the positive feedback of increasing water vapor at given pressure levels, the water vapor concentration at set distances below the tropopause might decrease (?), so that the CO2 band would actually be chasing the water vapor band, delaying their ultimate merging… (????) Interestingly, after the expansion of the CO2 band to longer wavelengths loses some effect (if that does happen at some point), there would still be an effect from the expansion at the other edge of the CO2 band into the atmospheric window.

    Of course, changing temperatures will also shift the peak wavelength of emission, but the shift could go in opposite directions between the top and bottom of the troposphere if the tropopause level is cooling.

    All of which has little to do with the prospect for AGW – a mere doubling or two of CO2, catastrophic though that could be to ecosystems and economies and societies, would not reach any limit where the bands run into each other, etc.

  20. 420
    Peter Plail says:

    I’m not sure whether this will meet your strict criteria to be a valid article, but it appears to show statistacally significant correlation between GCRs and tree ring growth – a stronger correlation than with, for example, temperature.

    http://www3.interscience.wiley.com/journal/122597017/abstract?CRETRY=1&SRETRY=0

  21. 421
  22. 422
    Patrick 027 says:

    … Interesting thing about CO2 forcing – because air-to-air net LW radiant energy exchanges are hindered by both lack of absorption/emission, and by too much opacity blocking photons from traveling over significant temperature variations, the greatest air to air net radiant energy fluxes tend to occur at intermediate opacity (assuming scattering is not too large a part of that, which is a very good assumption for Earthly conditions for LW fluxes) relative to the spatial (vertical) scales of temperature variations.

    Since, past the point of saturation at the center of the band, the width of the intervals of intermediate opacity do not change much as they shift outward from the center, adding CO2 changes mainly the net LW cooling of the surface to space, to the atmosphere, and the net LW cooling of the layers of atmosphere to space. (Except at sufficiently high altitudes where temperature variations occur very sharply relative to the mass distribution.)

    Actually, CO2 forcing is larger at the tropopause than at the surface (perhaps ?mostly? due to water vapor overlap?).

    The overall shape of the water vapor spectrum is quite different, so the water vapor feedback concievably may slow the upward propagation of LW radiation within the air itself, thus requiring a higher convective heat flux to balance the radiative fluxes, depending on what happens to the distribution of SW heating. The temperature increase itself will tend to increase net LW fluxes because for the same temperature difference, the difference in blackbody radiant intensity increases with increasing temperature, especially at short wavelengths. But the decreasing lapse rate in much of the lower troposphere (except polar regions) would have the opposite effect. Although greater warming at nightime at the surface would … well you get the idea.

  23. 423
    Patrick 027 says:

    ” thus requiring a higher convective heat flux”

    In addition to the changes in the net LW cooling of the surface.

  24. 424
  25. 425
    Patrick 027 says:

    “” thus requiring a higher convective heat flux”

    In addition to the changes in the net LW cooling of the surface.”

    I mean, in addition to the convective flux changes required by the changes in net LW cooling of the surface.

    PS while on that point, I think I realized something about the land-amplification of warming relative to the ocean.

    Of course, this is because the oceans have higher heat capacity. But I had wondered, shouldn’t the effect then be largely reduced after several decades past stabilized forcing, and then eventually go to zero after the warming signal has fully penetrated the deep ocean and thus equilibrated the temperature of upwelling water?

    But I forgot about the diurnal temperature cycle. Given the way convective maintenance of the lapse rate works, and the slowness (relative to day-to-day and hourly changes) of radiative cooling of the atmosphere (generally around 1 K per day within the troposphere), the tropospheric temperatures outside the boundary layer should tend to be set by daytime maximum surface temperatures. As tropospheric air is advected around, the oceans downwind of land will be indirecly radiatively affected more by daily high temperatures on land more than daily average land surface temperatures. So it makes since that at climatic equilibrium, sea surface temperature changes might be more similar to daily high land surface temperature changes, which will be less than daily average land surface temperature changes, so long as it is forced by the greenhouse effect, and aside from other effects. Am I on to something, here? (PS the water vapor feedback by itself would tend to subdue two distinctions of positive solar forcing – the increased diurnal range and stratospheric warming. But my understanding is that the signs of those changes are still expected to be the same (stratospheric warming, larger diurnal range) even at equilibrium (before equilibrium, the stratospheric and diurnal range responses will be ahead of the water vapor feedback).

  26. 426
    Ray Ladbury says:

    Rene,
    Try to wrap your head around the idea that 1)science is curiosity driven, and 2)if you fudge your results in science–even slightly–your career, which you worked for a couple of decades to get into, is effectively over. How’s that for incentive to stay honest. Do you have any similar incentive?

  27. 427
    CM says:

    Rene #405,

    The basic argument is that any funding of anything is done to advance the funder’s objectives.

    The scientists sitting on funding panels tend to be oddly partial to research that could gain interesting new knowledge, as Gavin is trying to tell you.

    Beyond that, climate science is generally funded by governments. The objectives of government include the protection of public health and safety; the maintenance of public infrastructure; the growth of the national economy; the uninterrupted supply of food, water, and other vital commodities; and the defense of national security. Governments advance these objectives inter alia by funding climate science to learn how much of a threat global warming will be in all these areas, and how they can plan to prevent it or adapt to the consequences.

    And where the emerging ideas have large implications for the welfare of the funder, assumptions of sustained impartiality strain credibility.

    Indeed. You might suspect publicly funded scientists of being partial to public welfare.

  28. 428
    Patrick 027 says:

    Re chris 413 – Nice reading list!

    Re sidd – excellent point about the warming oceans.

    “And the Southern Ocean is freshening”

    If ice can’t explain it (?), I would look at less evaporation (warmer, more humid air from elsewhere advected over upwelling water that has not changed as much in temperature (yet)) or more precipitation.

  29. 429
    Mark says:

    rene, the only way you can honestly believe that such a conspiracy could exist is that you personally are extremely venal and would take any bribe for any amount and do what the briber wants as long as you don’t get hurt.

    Since you have experience only about how you think, this is the only way you can honestly think your scenario has *any* legs at all.

    Or you just want to slur those who you hate.

  30. 430
    Patrick 027 says:

    … Actually, additional CO2 will affect net LW fluxes among more humid air, clouds, the surface, and space, and between any of those and dryer air, just not so much among the different layers of relatively dryer air – I think.

    (So in the hypothetical situatuation of a continuous blanket of cirrus clouds, adding CO2 would tend to cool the cirrus cloud layer from below, increasing deep convection through the troposphere.)

  31. 431
    Steve Fish says:

    I agree with Rene, funding agencies do have agendas and “seek to further their goals when allocating funds.” For example, my experience with the NIH regarding my applications and my instructions as a reviewer was that the agency was very clear that grant applications fair best if the proposed research was likely to produce significant findings and was doable by the applicant utilizing the proposed methods. It was all very biased against inferior science and blatantly unfair to poorly prepared researchers.

    As a very biased person I think that some biases are useful. Steve

  32. 432
    Peter Plail says:

    Hank Roberts
    Thank you for pointing me to the additional information. It seems that the Finns’ work tends to support the findings of the British study albeit with a lower correlation. I don’t understand why this is dismissed.

  33. 433
    sidd says:

    Re: Southern Ocean freshening

    Please not to trust my quick calculation that Antarctic melting is too small to cause the freshening. The color coding on the grafs in Schuckman et al. are not sufficient for my eyes to accurately estimate. Really need the ARIVO or CORA or ISAS data for this, i think it is on the net, but havent had the time to look yet.

  34. 434
    Mark says:

    “I agree with Rene, funding agencies do have agendas and “seek to further their goals when allocating funds.” ”

    But that isn’t what Rene is saying.

    He’s saying that the whole AGW thing is wrong because these scientists will be bribed.

    And again, all it takes is people looking at reality and the lie is punctured.

    If denial of AGW were right, why is it that Lindzen et al have not yet managed to make any progress in finding even a description of what’s going on instead?

    Either they’re inadequate to the task or they’re wrong.

  35. 435
    Hank Roberts says:

    Peter Pail writes

    > I don’t understand why this is dismissed

    Blog science isn’t science, remember.

    There hasn’t been time for dismissal of that paper by any scientist in the field that I’ve seen. It was published what, four days ago.

    Look at the references (link is with the paper) and check Scholar for papers citing _them_ to get a feel for how that area of science works.

    It’s not a new idea; look with Google Scholar: http://scholar.google.com/
    Put this into the search box: correlation “cosmic ray” “plant growth”

    That finds: about 127 papers; you can narrow the search yourself as you figure out the key terms and read more.

    But if you start searching for papers mentioning correlation and any two things you can think of that might be somehow related, you’ll find them. Then you have to see if the idea went anywhere — if the paper was cited by any later writers, if it led to any interesting results over time.

    Most correlations are coincidence or related to something else.

    You learn this by studying or trying things. I did a fifth grade science project in the 1950s, taking bean seeds to the local facility with an electron beam and asking the lab people there to irradiate them for me — they did, I grew them out, and the ones hit by the low level electron beam actually germinated better and grew faster than the controls.

    No, I didn’t prove (or even think) in fifth grade that radiation improved the growth of the bean seeds. Most likely explanation, well known at the time — you can preserve food by irradiating it. Low intensity electron beam would mostly damage viruses, bacteria, and mold normally present on the outside of dried beans. (The medium dose beans grew poorly, the high dose ones mostly unsuccessful.)

    Have a look at the hundred-odd papers turned up searching on cosmic rays and plant growth; don’t pay attention to people on blogs who think each brand new paper is conclusive proof but who never bother to read the actual journals to see what’s already been published and watch for later work.

  36. 436
    Hank Roberts says:

    TSI seems to be past the minimum:

    http://www.leif.org/research/TSI-SORCE-2008-now.png

    Explained: “The adjusted flux is shown with its noon value [at 20:00 UT] that sits around 70 flux units. You can see that TSI has begun its slow upwards climb and that F10.7 background is also climbing [up from minimum values around 66], so SC24 is on its [slow] way. The solar mean field [MF] shows the magnetic field in low-latitude coronal holes and since there aren’t any of these yet, will stay low for a while.”

    (I quote from his post in a ham radio thread; lots of us who are hams are watching and waiting for radio propagation changes)

  37. 437

    MG:

    To top it all off, during the period of anthropogenically-induced warming (ie., post-industrial), the correlation between temperature and CO2 is actually not that impressive,

    Look again. http://BartonPaulLevenson.com/Correlation.html

  38. 438

    I’ve been in a bit of a dust up with moderately well known denialist William Kininmonth at The Australian, which I’ve summarized on my blog.

    The punchline: he is now claiming that past records of solar output from sunspots are unreliable, after claiming less than a year ago that they were robust. And he accuses me of misunderstanding science.

    He also missed the rather obvious point that I was talking about the recent past, and proceeded to say those records are robust. If only it was always this easy.

  39. 439

    We should specify what we mean by saturation. To an atmosphere physicist, CO2 saturation refers to the fact that the line centers are black. To an AGW denier, it means “adding more CO2 makes no difference.”

    http://BartonPaulLevenson.com/Saturation.html

  40. 440
    Paul Gosling says:

    Re 435

    Yes its a dangerous game laying too much significance on correlations between tree rings and environmental factors, particularly when the correlation is good in some time periods but diverges in others.

  41. 441
    manacker says:

    Patrick 027

    Not wanting to get into your discussion with Peter Taylor, wherein you express a higher degree of confidence in CGMs then he does (to simulate and even be able to predict our planet’s climate), there was one point you made that caught my eye.

    In defending the ability of GCMs to simulate our climate even when there are uncertainties, you wrote:

    “The uncertainties come in with processes that cannot be explicitly resolved by the grid scale used, which itself cannot be arbitrarily small because of limited computing power. Such processes must be parameterized. But that is not a guessing game – the possible relationships can be constrained by other modelling excercises and by observations.”

    Here there is a very good case in point.

    The net cooling impact of clouds is generally known. Low altitude (water droplet) clouds reflect incoming solar radiation (climate forcing is estimated to be –48 W/m^2). High altitude (ice crystal) clouds allow incoming solar radiation to pass through, but absorb outgoing LW radiation (climate forcing is estimated to be +30 W/m^2). The net forcing impact of clouds is –18 W/m^2, or over 4 times as high as the GH warming expected from a doubling of atmospheric CO2.
    http://www-ramanathan.ucsd.edu/FCMTheRadiativeForcingDuetoCloudsandWaterVapor.pdf

    [Response: Apples-to-oranges comparison. How does a $1 price rise for a bag of rice become inconsequential if potatoes are $4 a pound? Don’t play games here. – gavin]

    Naturally caused changes in cloud cover are not considered by the GCMs cited by IPCC

    [Response: Nonsense. Clouds change naturally in GCMs as well as changing due to aerosol indirect effects, or contrails, etc. – gavin]

    (see Peter Taylor’s book for more on this).

    The GCMs consider the impact of clouds only as feedbacks to the warming caused by increases in anthropogenic GHGs. These are estimated to contribute +1.3°C to the 2xCO2 temperature impact (or climate sensitivity) of +3.2°C total (IPCC AR4 Ch. 8).

    [Response: Wrong again. Models show a large range of responses – some which show almost none, others that show a lot. – gavin]

    But back to your statement.

    A recent study based on physical observations in the tropics (Spencer et al.), showed that clouds exhibit a strongly negative feedback with warming, of at least the same order of magnitude as the positive feedback from the model outputs cited by IPCC. I would submit that these are the observations that should now be used to constrain the GCMs, as you suggest.

    [Response: A complete misreading of the study (though to be fair to you, this is how the author has described it outside of the literature). He looked however at the impact of a dynamical mode of variability (the ISO a.k.a the MJO) and looked at the effect it had on both SST and clouds. This is very certainly not the same as the impact of SSTs have on clouds despite what might be claimed. – gavin]

    Then there is the question of parameterization.

    GCMs have not been able to do a good job of simulating the impact of clouds, due to the limited computing power, which you mentioned.

    A study entitled: “Climate sensitivity and cloud response of a GCM with a
    Superparameterization” touches on this problem.
    ftp://eos.atmos.washington.edu/pub/breth/papers/2006/SPGRL.pdf

    “Cloud processes in conventional GCMs rely on parameterizations to represent motions smaller than the resolved grid scales and to calculate the fraction of the sky covered by cloud within each grid box.”

    “Using SP-CAM, we present the first global atmospheric climate sensitivity experiments in a GCM with superparameterization.”

    “The world’s first superparameterization climate sensitivity results show strong negative cloud feedbacks driven by enhancement of boundary layer clouds in a warmer climate.”

    “The CAM-SP shows strongly negative net cloud feedback in both the tropics and in the extratropics, resulting in a global climate sensitivity of only 0.41 K/(W m-2).”

    All the models cited by IPCC AR4 chapter 8 indicated a net positive feedback from clouds, although there was some disagreement on the magnitude, and IPCC has made no mention of this study or of superparameterization, although the study was published in March 2006, before the final deadline.

    But, again, these physical observations and model studies using superparameterization actually confirm your statement of how the process should deal with uncertainty.

    At the same time they provide evidence to support the premise that the net feedback from clouds is strongly negative and, thus, that the 2xCO2 climate sensitivity is likely to be no higher than 1°C (rather than 3.2°C as assumed by the GCMs cited by IPCC).

    [Response: Wrong again. Even the model with close to zero cloud feedback has climate sensitivity much larger than this. Plus the constraints from paleo make it almost impossible that sensitivity could be this low. – gavin]

    Would you agree that I have understood your statement on how the modeling process works to resolve uncertainty through parameterization and constraints based on physical observations?

    Max

  42. 442
    Mark says:

    “To an AGW denier, it means “adding more CO2 makes no difference.””

    Although that’s never true, is it.

    Even if you take their misapplication of Beer’s law, you only asymptotically get to 1.0 fractional loss.

    The thing is, they look at beers law and say “that is all there is”.

    There isn’t.

    Assume, for example, that the GG layer is 3 optical depths deep. practically 100% of the IR is blocked and re-radiated.

    The denialist then says “so therefore adding another layer of greenhouse gasses cannot change a thing, because 100% of the ground’s IR is blocked”.

    WRONG.

    The IR isn’t blocked. That layer of GG reradiates it. Half going down, half going up.

    So if you double the GG layer, you have two layers. the one touching the ground reradiates upward but that is now blocked practically 100% by that second layer. And, just like that first layer warmed the ground by blocking the IR leaving, that second layer is warming the layer below.

    But warming a layer increases its IR output.

    So that first layer, now warmed by the layer above reradiates its energy and half goes up, but half goes down.

    Therefore the ground is warmed by the extra warming the second layer did to the first.

  43. 443
    manacker says:

    Gavin

    Thanks for your comments to my post directed at Patrick 027.

    Let me see if I can respond.

    The reference to the Ramanathan and Inamdar study did indeed show that clouds have a net cooling effect on our climate.

    You commented that this was an “apples to oranges” comparison.

    There is no “apples to oranges” comparison made or intended here, Gavin, just stating what the study concluded, namely that clouds on average have a cooling impact on our climate.

    [Response: Much as I’d love to have the time to point you to dictionary definitions of the word ‘comparison’ or school you in the difference between an absolute level and a change in that level, or point out (yet again) that you are indulging in strawman argumentation, I really don’t. So please go and play games somewhere else. – gavin]

    [edit]

  44. 444
    Mark says:

    “The reference to the Ramanathan and Inamdar study did indeed show that clouds have a net cooling effect on our climate.”

    Ah, so all the other studies (and did this one use a “computer model”?) that say it’s a net warming are wrong?

    I would ask why, but you won’t answer and just waste more time.

  45. 445
    MG says:

    Chris: Thanks for the references. I will get to them in November, so you might not get a proper reply, but thanks for taking the time.

  46. 446

    Mark,

    That was a very good summary of why the saturation argument fails. Nicely done.

  47. 447
    thingsbreak says:

    Kulmala et al. 2009 and Overholt et al. 2009 didn’t seem to get nearly the kind of attention that Svensmark or Shaviv pull. Funny that.

  48. 448
    Nick D. says:

    The most important point made in this article/rant is at the end when the media is mentioned to have overrepresented the GCR proponents. The fact is, is that the boring, monotonous, and amazing discoveries that science, and specifically climatology, makes are being underrepresented by the media. To average Joe the Plumber, the media telling them that GCR’s are uncorrelated with average global temperature is A) uninteresting because he is simply uneducated on the issue and has no idea what GCR’s are or how to spell it, and B)improbable, since people don’t pay attention to what they don’t understand and they are uninterested in things do nothing to challenge their current understanding of a situation, they will naturally cling to GCR’s as being something to talk about with their idiot buddies during the commercials of a football game. They would rather say “dude, did you know global warming isn’t real? They just found out that this thing called RCG’s are makin in hot.” than “dude, did you know GCR’s are totally uncorrelated with global warming, and is the widely accepted scientific view of their relationship?”.

    So what I’m trying to say, is that the world doesn’t need more media telling people what’s interesting. They need more scientists doing so. The gap between the scientific community and Joe the Plumber needs to be closed; and it needs to be closed by YOU! All of you scientists out there that have any idea how to speak to people and aren’t totally socially awkward need to make their voice heard. Open science to Joe and Jane the plumber, they are interested if it becomes accessible to them.

  49. 449
    Naindj says:

    Mark 442,
    To my understanding, saturation means 100% of the radiation (for the wavelengths where CO2 is active) is blocked and re-radiated down. The extra heat induced by the re-radiation down (100% minus the heating of the layer itself) is ALREADY taken into account.
    So there is no radiation up. So if you add a layer above, it will have no radiation at these wavelengths to deal with.
    And if you add a layer under (that is your example, isn’t it?), you simply redistribute the temperatures, but the radiation bilan is the same. i.e. ok the layer near the ground is heated and radiates more. But then it means that the ground is less heated and emits less…
    Or I missed something?

  50. 450
    Hank Roberts says:

    Naindj writes:

    “… 100% of the radiation … is blocked and re-radiated down….”

    “… down … no radiation up …”?! Think this through.

    How do you imagine it could be that the CO2 molecules would know to emit radiation only downward, not sideways or up?

    Down, into thicker air, toward the ground, but not sideways or up into the cold thin upper air toward space?

    Down, so any photograph in those wavelengths would see — what, a completely dark surface with no emission upward?

    I won’t say anything sarcastic here. You somehow believe this. I would very much like to know why you think this could be true. Where did you find the idea? Why do you think it’s believable?


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