Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.


Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe

Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...

New? Register here
Forgot your password?

Latest Posts


ConCERN Trolling on Cosmic Rays, Clouds, and Climate Change

Posted on 26 August 2011 by thingsbreak

Guest repost from The Way Things Break.

Clouded “Reporting”

Depending on where you get your science news, you might be hearing claims to the effect that CLOUD at CERN has “proven that cosmic rays drive climate change”, or something to that effect. That’s certainly the impression that climate “skeptics” would like you to get. Unfortunately for “skeptics” (and if we don’t reign in greenhouse emissions, everyone else), it’s not true. While cosmic rays may have some influence on cloud formation, they are not responsible for the present, human-driven climatic change or alleged changes in the geologic past.

What’s the deal?

Although seemingly out of fashion for a while until recently, the “cosmic rays are driving climate” myth has long been one of the mainstays of the self-contradictory climate “skeptic” argument stable, and it’s something covered fairly often at The Way Things Break (previous posts here, here, here, here, here, and here). And as with any good falsehood, it starts with a kernel of truth.

It is completely accepted in mainstream science that galactic cosmic rays (GCRs) might be able to influence the nucleation process of potential cloud condensation nuclei (CCN), and that it’s conceivable that this could influence cloud behavior at some level. As the IPCC AR4 noted (I’ll include the full text at the end, after the jump):

By altering the population of CCN and hence microphysical cloud properties (droplet number and concentration), cosmic rays may also induce processes analogous to the indirect effect of tropospheric aerosols. The presence of ions, such as produced by cosmic rays, is recognised as influencing several microphysical mechanisms (Harrison and Carslaw, 2003). Aerosols may nucleate preferentially on atmospheric cluster ions. In the case of low gas-phase sulphuric acid concentrations, ion-induced nucleation may dominate over binary sulphuric acid-water nucleation.

While a plausible mechanism exists, real world verifications are necessarily difficult to undertake. The CLOUD project at CERN is seeking to do exactly that. The “skeptic” and right wing blogospheres are abuzz because Jasper Kirkby, et al. have just published the first results in Nature (Kirkby 2011).

RealClimate has a good rundown of what Kirkby et al.’s results do and do not mean. The short version is that Kirkby et al. do find increased aerosol nucleation under increased ionization (i.e. “more cosmic rays”), particularly in the mid-troposphere, but the effect is smaller at warmer, lower levels where the cosmic ray-climate myth proponents claim it has its greatest climatic effect. Lead author Jasper Kirkby has tried to set the record straight, stating (all following emphases mine):

[The paper] actually says nothing about a possible cosmic-ray effect on clouds and climate, but it’s a very important first step.

While their results provide some confirmation of the potential mechanism by which GCRs might induce cloud nucleation, they in no way demonstrate that GCRs do significantly promote cloud formation in the real world, let alone support the myth that GCRs drive significant climatic change.

“But wait!” I’m sure some of you may be thinking, “the Kirkby et al. results certainly don’t disprove GCRs drive significant climatic changes.” And that’s true enough.

How Do We Know That Cosmic Rays Aren’t Driving Significant Climatic Change?

In reference to the present anthropogenic climatic changes that we’re driving through alteration of the planetary energy balance notably through greenhouse gas emissions, we can theorize what certain “fingerprints” of enhanced greenhouse warming should look like, and examine observational data to see whether those fingerprints show up. And they do.

Moreover, we can examine the claims made by Svensmark, Shaviv, and others who proclaim GCRs drive climate and see whether or not they hold up. They don’t:

We can look at the paleoclimatic record during periods of significant changes in GCR activity, and there is no corresponding change in climate, e.g. the Laschamp excursion ~40kya (Muscheler 2005).

We can examine the change in GCRs in response to solar variability over recent decades or the course of a solar cycle, and find there is no or little corresponding change in climate (Lockwood 2007, Lockwood 2008, Kulmala 2010).

We can look at alleged correlations between GCRs and climate in the geologic past due to our sun passing through galactic spiral arms, and find that these “correlations” were based on an unrealistic, overly-simplified model of spiral structure and are not valid (Overholt 2009). Standard climatic processes (like CO2) more parsimoniously explained the climatic changes even before taking the flawed spiral model into account (Rahmstorf 2004).

We can examine the specific mechanisms by which Svensmark and others have claimed GCRs influence climate via cloud behavior and show that alleged correlations between GCRs and clouds were incorrectly calculated or insufficiently large, proposed mechanisms (e.g. Forbush decreases) are too short lived, too small in magnitude, or otherwise incapable of altering cloud behavior on a large enough scale to drive significant climatic change (Sloan 2008, Erlykin 2009, Erlykin 2009a, Pierce 2009, Calogovic 2010, Snow-Kropla 2011, Erlykin 2011).

Basically, what’s actually been demonstrated by Kirkby, et al. isn’t at odds with the IPCC. What is at odds with the IPCC hasn’t been demonstrated by Kirkby, et al. And the claims by Svensmark, Shaviv, and other ‘GCRs drive climate’ proponents have been debunked at pretty much every step of the way. GCRs may have some influence on cloud behavior, but they’re not responsible for significant climatic changes now or in the geologic past.

To Be Continued?

The CLOUD project at CERN is essentially just getting started. Its preliminary findings will help aerosol modelers, and hopefully it will continue to provide useful results. After the initial furor of “skeptic” blog-spinning dies down, cosmic rays will probably find themselves falling out of favor once again. But there’s no such thing as too debunked when it comes to myths about climate change, and there’s little chance this will be the last time cosmic rays will be trotted out to claim that we don’t need to reduce greenhouse gas emissions.


  • Calogovic, J., et al. (2010): Sudden cosmic ray decreases: No change of global cloud cover. Geophysical Research Letters, 37, L03802, doi:10.1029/2009GL041327.
  • Erlykin, A.D., et al (2009): Solar activity and the mean global temperature. Environmental Research Letters, 4, 014006, doi:10.1088/1748-9326/4/1/014006.
  • Erlykin, A.D., et al (2009a): On the correlation between cosmic ray intensity and cloud cover. Journal of Atmospheric and Solar-Terrestrial Physics, 71, 17-18, 1794-1806, doi:10.1016/j.jastp.2009.06.012.
  • Erlykin, A.D., and A.W. Wolfendale (2011): Cosmic ray effects on cloud cover and their relevance to climate change. Journal of Atmospheric and Solar-Terrestrial Physics, 73, 13, 1681-1686, doi:10.1016/j.jastp.2011.03.001.
  • Kirkby, J., et al. (2011): Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation. Nature, 476, 429–433, doi:10.1038/nature10343.
  • Kulmala, M., et al. (2010): Atmospheric data over a solar cycle: no connection between galactic cosmic rays and new particle formation. Atmospheric Chemistry and Physics, 10, 1885-1898, doi:10.5194/acp-10-1885-2010.
  • Lockwood, M., and C. Fröhlich (2007): Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature. Proceedings of the Royal Society: A. 463, 2447- 2460, doi:10.1098/rspa.2007.1880.
  • Lockwood, M., and C. Fröhlich (2008): Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature. II. Different reconstructions of the total solar irradiance variation and dependence on response time scale. Proceedings of the Royal Society: A, 464, 1367-1385, doi:10.1098/rspa.2007.0347.
  • Muscheler, R., et al. (2005): Geomagnetic field intensity during the last 60,000 years based on 10Be and 36Cl from the Summit ice cores and 14C. Quaternary Science Reviews, 24, 16-17, 1849-1860, doi:10.1016/j.quascirev.2005.01.012.
  • Overholt, A.C., et al. (2009): Testing the link between terrestrial climate change and galactic spiral arm transit. The Astrophysical Journal Letters, 705, 2, L101, doi:10.1088/0004-637X/705/2/L101.
  • Pierce, J.R., and P.J. Adams (2009): Can cosmic rays affect cloud condensation nuclei by altering new particle formation rates? Geophysical Research Letters, 36, L09820, doi:10.1029/2009GL037946.
  • Rahmstorf, S., et al. (2004): Cosmic Rays, Carbon Dioxide, and Climate. Eos Transactions AGU, 85(4), doi:10.1029/2004EO040002.
  • Sloan, T., and A.W. Wolfendale (2008): Testing the proposed causal link between cosmic rays and cloud cover. Environmental Research Letters, 3, 024001, doi:10.1088/1748-9326/3/2/024001.
  • Snow-Kropla, E.J., et al. (2011): Cosmic rays, aerosol formation and cloud-condensation nuclei: sensitivities to model uncertainties. Atmospheric Chemistry and Physics, 11, 4001-4013, doi:10.5194/acp-11-4001-2011.

The full text from the IPCC AR4 section on cosmic rays and climate:

When solar activity is high, the more complex magnetic configuration of the heliosphere reduces the flux of galactic cosmic rays in the Earth’s atmosphere. Various scenarios have been proposed whereby solar-induced galactic cosmic ray fluctuations might influence climate (as surveyed by Gray et al., 2005). Carslaw et al. (2002) suggested that since the plasma produced by cosmic ray ionization in the troposphere is part of an electric circuit that extends from the Earth’s surface to the ionosphere, cosmic rays may affect thunderstorm electrification. By altering the population of CCN and hence microphysical cloud properties (droplet number and concentration), cosmic rays may also induce processes analogous to the indirect effect of tropospheric aerosols. The presence of ions, such as produced by cosmic rays, is recognised as influencing several microphysical mechanisms (Harrison and Carslaw, 2003). Aerosols may nucleate preferentially on atmospheric cluster ions. In the case of low gas-phase sulphuric acid concentrations, ion-induced nucleation may dominate over binary sulphuric acid-water nucleation. In addition, increased ion nucleation and increased scavenging rates of aerosols in turbulent regions around clouds seem likely. Because of the difficulty in tracking the influence of one particular modification brought about by ions through the long chain of complex interacting processes, quantitative estimates of galactic cosmic-ray induced changes in aerosol and cloud formation have not been reached.

Many empirical associations have been reported between globally averaged low-level cloud cover and cosmic ray fluxes (e.g., Marsh and Svensmark, 2000a,b). Hypothesised to result from changing ionization of the atmosphere from solar-modulated cosmic ray fluxes, an empirical association of cloud cover variations during 1984 to 1990 and the solar cycle remains controversial because of uncertainties about the reality of the decadal signal itself, the phasing or anti-phasing with solar activity, and its separate dependence for low, middle and high clouds. In particular, the cosmic ray time series does not correspond to global total cloud cover after 1991 or to global low-level cloud cover after 1994 (Kristjánsson and Kristiansen, 2000; Sun and Bradley, 2002) without unproven de-trending (Usoskin et al., 2004). Furthermore, the correlation is significant with low-level cloud cover based only on infrared (not visible) detection. Nor do multi-decadal (1952 to 1997) time series of cloud cover from ship synoptic reports exhibit a relationship to cosmic ray flux. However, there appears to be a small but statistically significant positive correlation between cloud over the UK and galactic cosmic ray flux during 1951 to 2000 (Harrison and Stephenson, 2006). Contrarily, cloud cover anomalies from 1900 to 1987 over the USA do have a signal at 11 years that is anti-phased with the galactic cosmic ray flux (Udelhofen and Cess, 2001). Because the mechanisms are uncertain, the apparent relationship between solar variability and cloud cover has been interpreted to result not only from changing cosmic ray fluxes modulated by solar activity in the heliosphere (Usoskin et al., 2004) and solar-induced changes in ozone (Udelhofen and Cess, 2001), but also from sea surface temperatures altered directly by changing total solar irradiance (Kristjánsson et al., 2002) and by internal variability due to the El Niño-Southern Oscillation (Kernthaler et al., 1999). In reality, different direct and indirect physical processes (such as those described in Section 9.2) may operate simultaneously.

0 0

Printable Version  |  Link to this page


1  2  Next

Comments 1 to 50 out of 56:

  1. TWTB. Excellent summary. I was worried that this one would find it's way around the world before the truth put its shoes on, but in this instance rationality seems to be hot on the heels of propaganda. Well done.
    0 0
  2. Kirkby's name has a 'k'; it's not Kirby. But why repost an entire article rather than just link to it on our existing 'its cosmic rays' rebuttal?
    0 0

    [DB] "Kirkby's name has a 'k'; it's not Kirby"

    Fixed.  It was interesting to note the sponsor of the rollover ads on the Nature Kirkby et al download page:


    What's next, Pathos (the 5th Musketeer)?

  3. Environmental Research Web did a write up: Quote: "Kirkby shares Pierce's caution. He argues that CLOUD's results "say nothing about cosmic-ray effects on clouds" because the aerosols produced in the experiment are far too small to seed clouds."
    0 0
  4. Unfortunately Scientific American has a new story with the title and by line; Cloud Formation May Be Linked to Cosmic Rays Experiment probes connection between climate change and radiation bombarding the atmosphere. And at least it does include the quote; "[The paper] actually says nothing about a possible cosmic-ray effect on clouds and climate, but it’s a very important first step."
    0 0
  5. How does NatureNews get away with the headline Cloud formation may be linked to cosmic rays when the Kirkby paper in question, entitled Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation, does not offer any new support for this claim? It's bad enough when the usual suspects are misleading and/or incorrect. Readers here should object to this error with comments on NatureNews.
    0 0
  6. No, Muon--the headline is true. Cloud formation may indeed be linked to cosmic rays. The headline would have been just as true before CLOUD. And the fact that the title has nothing to do with the report means little. Half my freshmen do that every semester. And certainly CLOUD formation was linked to cosmic rays.
    0 0
  7. @5 Because their results do show the possibility that aerosol nucleation is enhanced by cosmic rays. Whether that translates into any significant effect in real world cloud cover is another story, but the mechanism has been somewhat supported.
    0 0
  8. Reading some of the responses to the story I wrote on these results for New Scientist made me realise there is a major misunderstanding on the part of those hailing these results as “proof” that climate rays affect climate. Gavin did explain this in his RealClimate post, but it might be worth restating here in plainer terms: The CLOUD team did find cosmic rays produced a relatively large increase in the aerosol nucleation rate. However, they were comparing no cosmic rays with having cosmic rays (the chamber was shielded). That does not reflect what actually happens in reality: our atmosphere is always being struck cosmic rays, there is never a time when there are no cosmic rays. Changes in the sun's activity produce only tiny changes in the average number of cosmic rays hitting the atmosphere, which means changes in the nucleation rates in the atmosphere due to changes in cosmic rays intensities are going to be much smaller than the 2 to 10 times factor reported in the study.
    0 0
  9. #6/#7: I'm sorry, I find that kind of reporting to be misleading in the extreme. The paper talks about ammonia in parts per trillion as providing nucleation enhancement; this introduces an entirely new independent variable. The news release barely mention this; it is nothing more than a restatement of the premise of the original experiment. The RC analysis (mentioned on the original It's cosmic rays thread) takes this apart even further: ... despite going to a lot of trouble to make sure the chamber was ultra-free of contaminants, the researchers found that within most of the aerosols that formed, there were traces of organic nitrogen compounds that must have been present in almost undetectably low concentrations. So there are uncontrolled contaminants in the experiment. Oops. And then there's the energy question: From the news release, high-energy protons seemed to enhance the production of nanometre-sized particles from the gaseous atmosphere by more than a factor of ten. Great, that's what they were looking to find (although the use of 'seemed' makes it a tad ambiguous). However, as reported earlier here, a similar experiment ... found that this effect also took place when they used a radioactive sodium source, which produces gamma rays. So which is it? High energy GCRs, simulated by a particle beam in a contaminated chamber? Low energy naturally occurring gamma rays? They may as well have written a news release that it could all be caused by LGM rather than GCR. Yeah, it could be. That's crappy science reporting; no doubt the deniersphere will run with it. DSL, I'm shocked; I don't let my high school students get away with reporting unsupported experimental conclusions - or using words like 'could be' and 'seemed' in their writeups.
    0 0
  10. Muon: "DSL, I'm shocked; I don't let my high school students get away with reporting unsupported experimental conclusions - or using words like 'could be' and 'seemed' in their writeups." Neither do I, as they discover in the feedback they receive on their first drafts. And these are college freshmen (essentially high school students at that point). The comment was lightly ironed. I agree. It's more than disappointing that Nature would cave to market forces and publish that report with that title.
    0 0
  11. It seems like a lot of the deniers are claiming that this new study shows that climate models are all wrong. For instance here And here Could someone please explain the connection and if they are right or are they reading way too much into the findings of the CLOUD study? thanks
    0 0
  12. davidkirtley#11: "claiming that this new study shows that climate models are all wrong. " The prediction here didn't have to wait long. Multiple choice: a. The deniers are reading too much into the new study b. The new study doesn't reach a firm conclusion c. The new study doesn't deal with climate models d. The deniers have read the news release and not the paper; the two do not say the same thing e. All of the above See comments above, the RC analysis and the prior It's cosmic rays thread.
    0 0
  13. Hang on though-even if cosmic rays are significantly linked to cloud formation-then shouldn't we be seeing a *cooling* effect right now? After all, decreasing sunspots also means increased GCR's. Increasing GCR's means increased cloud formation (or so the "skeptics" tell us) & increased cloud formation means increased albedo-hence an overall *cooling* effect. If I were a "skeptic", I'd be trying to *disprove* the link between GCR's & clouds ;-).
    0 0
  14. I think the last sentence of the CLOUD press release puts everything into perspective. "However, it is premature to conclude that cosmic rays have a significant influence on climate until the additional nucleating vapours have been identified, their ion enhancement measured, and the ultimate effects on clouds have been confirmed.? My emphasis in bold.
    0 0
  15. RickG#14: How many full-throated deniers read even a short press release all the way to the last sentence? Headlines tell you everything you need to know, don't they?
    0 0
  16. To me, the most succinct observation for putting things into perspective was made by Gavin over at RealClimate, when he noted, "Of course, to show that cosmic rays were actually responsible for some part of the recent warming, you would need to show that there was actually a decreasing trend in cosmic rays over recent decades – which is tricky, because there hasn’t been (see the figure). " The cycles of GCRs are just that, cycles; there is no long term trend. You can't manufacture a long term trend out of data that doesn't have one; at least, you can't with math that has any relationship to the real world. So, it may be that GCRs have an influence on climate, and it might not be. Whatever the case, they can not be used to explain the warming trend.
    0 0
  17. This bit on Nigel Calder's blog has the 'it's cosmic rays' folks shouting, 'we told you so!' Calder apparently has dramatized the sequence of events in one experimental run to great success. I've interspersed a few questions that seem unanswered in his rendition.
    In an early-morning experimental run at CERN, starting at 03.45, ultraviolet light began making sulphuric acid molecules in the chamber, while a strong electric field cleansed the air of ions. It also tended to remove molecular clusters made in the neutral environment (n) but some of these accumulated at a low rate.

    Q1: That electric field also acts as shielding. Why are any molecular clusters accumulating in a shielded chamber with no particle beam input?

    As soon as the electric field was switched off at 04.33, natural cosmic rays (gcr) raining down through the roof of the experimental hall in Geneva helped to build clusters at a higher rate.

    Q2: Most cosmic ray workers would interpret 'natural cosmic rays' as the background flux of muons produced by atmospheric interactions with the solar wind (usually referred to as solar cosmic rays). How do they automatically identify this background as GCRs? And what sort of electric field shielded the chamber from muons (negatively charged) with energies on the order of GeVs?

    How do we know they were contributing? Because when, at 04.58, CLOUD simulated stronger cosmic rays with a beam of charged pion particles (ch) from the accelerator, the rate of cluster production became faster still.

    Q3: 'Stronger' in this context must mean higher energy. The original experimental design called for a pion beam on the order of 600 MeV, no 'stronger' than the background muons. Further, charged pions decay quickly to muons. What does this utterly critical statement mean? Are they actually investigating solar cosmic rays and not GCRs? Are they now saying that solar cosmic ray muons cause cloud nucleation as well? The mechanism for Be10 production requires higher energies, usually in the form of GCR-induced protons. It was the link to paleo abundances of Be10 that kicked off the whole GCR-climate link in the first place. Calder's dam on which global warming is said to break has some leaks.

    0 0
    Moderator Response: [muoncounter] CLOUD Project design sheets called for 3.5 GeV positive pion beam. A separate experiment in Denmark used 580 MeV.
  18. Has anyone actually suggested solar cosmic ray muons cause cloud nucleation?
    0 0
  19. Marcus, There has been a slight cooling effect recently, albeit it has not been significant leading some to call it a "lack of warming." However, many of us relate that to the recent La Ninas (2008 & 2011). The cooling was somewhat stemmed by the strong EL Nino of 2010. If the GCRs do enhance tropical cloud formation, then that could greatly impact ENSO. As Chris G states, these are just cycles. However, we must be careful not to misread the increasing (or decreasing) cycle stage as anything other that just that. I think RickG says it best with his emphasis on the conclusion of the CLOUD press release. The research to date neither proves nor disproves the GCR effect on climate.
    0 0
  20. 18 Tristan - give them time; eventually someone'll suggest it's all down to cloud nucleation by neutrinos.
    0 0
  21. Tristan#18: "muons" By using a 3.5 GeV pion beam, CLOUD is on the low edge of GCR energies and the high edge of solar cosmic ray energies. Pions decay to muons (in this case, anti-muons from positive pions). Nigel Calder's comment that the CLOUD beam produced 'stronger cosmic rays' than 'background' is false. To me, this is a glaring flaw in the experiment - if low energies cause the observed nucleation, then why aren't there all clouds, all the time? Since the climate-GCR connection originated with cosmogenic Be10 anomalies, why didn't CERN use their proton beam and thus simulate the kind of GCR that causes spallation? Similarly, the Danish group's claim that they saw the 'same effect' using a sodium gamma source should be very troubling (see the link under 'energy question' here).
    0 0
  22. Nice new video from Potholer debunking all the guff being spouted about the CERN paper.
    0 0
  23. Your arguments confuse Kirkby's beliefs with what he was forced to put in the paper during the more than a year of negotiations with reviewers to get it published. The paper does confirm Svensmarks earlier experiment which was condemned by people in the IPCC who are in denial that they could have made a mistake by betting on CO2. We will soon see whether Svensmark is right that cosmic ray and therefore clouds are a significant driver of climate. Though the solar wind has an 11 year cycle, that cycle has significant variation in period that correlate very well with La Nina/El Nino cycles. Theodor Landscheidt wrote a paper ten years ago showing an amazing connection. ttp:// Here is a later paper pointing out that the predictions were remarkably accurate. Archibald has done another prediction to 2050 based on a model that backtests amazingly well. The recent La Nina, which caused all of this year's terrible weather was part of that prediction. The future prediction is for a return to La Nina and another two decade spell of cooling. The real test of a theory is its ability to accurately predict. So far Svensmark's theory looks like a winner. We will see who is right in the near future. it won't be hard to do better than the dismal failure of the dire predictions based on the CO2 warming theory.
    0 0
  24. 22, tblakeslee,
    The real test of a theory is its ability to accurately predict. So far Svensmark's theory looks like a winner.
    This combination of words make no sense. Your criteria is an ability to accurately predict. Fine. What has Svensmark accurately predicted so far? How do you jump to "looks like a winner?" In September of 2009 he said:
    “In fact global warming has stopped and a cooling is beginning. No climate model has predicted a cooling of the Earth – quite the contrary. And this means that the projections of future climate are unreliable."
    Too bad we keep seeing record temperatures. You call that "cooling?" You call that an "accurate prediction?" Same for Achirbald. I read your link (as much as it made my skin crawl to visit WUWT). It's nonsense. It borders on a laughable joke. What of any value did you take away from that tripe?
    it won't be hard to do better than the dismal failure of the dire predictions based on the CO2 warming theory.
    And this is just a pathetic falsehood. Try How reliable are climate models for starters, and please spend less time just making things up.
    0 0
  25. tblakeslee#23: "The paper does confirm Svensmarks earlier experiment" No. From the earlier experiment: ... the researchers found that this effect also took place when they used a radioactive sodium source, which produces gamma rays, and as such claim that similar measurements in the future will not require expensive accelerators. -- emphasis added If low energy gammas produce sufficient ionization for cloud nucleation, why don't we see all clouds, all the time? Gammas are not modulated by the interplanetary magnetic field, so the entire basis of the GCR->cloud hypothesis is blown. The Kirkby paper says nothing about any of this. For the rest, please stay on topic and avoid citing WUWT, which is never considered a credible source. Refer to the Comments Policy; off topic comments are often quickly deleted.
    0 0
  26. Conclusions The superposed epoch analysis confirmed the statistically significant influence of CR intensity decrease on the state of the atmosphere. This is a new paper that seems to contradict what you're saying here. Is there a response?
    0 0
  27. Cole, thank you for providing once again confirmation that a certain crowd going by the motto "anything but CO2" will recycle any an all debunked arguments ad infinitum. Your interpretation of the Dragic et al paper is mistaken. This paper was first cited 3 and a half months ago ny Muoncounter, who knows about these things, as his handle indicates. I'll cite Muon's previous assessment on this, which comes straight from looking at the numbers in the Dragic paper: "The authors have a dataset running 41 years (1954-95); there are a grand total of 35 7% FDs in that period. If this is what is causing clouds to form, there isn't even 1 cosmic ray induced cloudy episode per year!" If one cloud event per year can modulate climate, what kind of effect would even a minute change in radiative forcing that operates 24/7 have? This is not even betting on the wrong horse, it's simply beating a dead one. The Dragic paper is indeed tragic news for GCRs/climate advocates. See this post, dating back to 3 and a half monts ago:
    0 0
  28. FYI, Cole has a history of carpet-bombing threads here at SkS with misunderstood, off-topic or fake-skeptic links.
    0 0
  29. Cole#26: "confirmed the statistically significant influence of CR intensity decrease on the state of the atmosphere." Except Agee et al 2011 unconfirmed that: It is concluded that the observational results presented, showing several years of disconnect between GCRs and lower troposphere global cloudiness, add additional concern to the cosmic ray-cloud connection hypothesis. In fact, this has been done in the most dramatic way with the measurement of record high levels of GCRs during the deep, extended quiet period of cycle 23-24, which is accompanied by record low levels of lower troposphere global cloudiness. So I guess CR 'intensity' alters the state of the climate (whatever that means) in a statistically significant way, if you ignore the years where it doesn't. Can you say 'robust results'?
    0 0
  30. The forbrush decrease paper was measuring the short term effects on cosmic rays (and temperature) caused by solar flares. The effect is measurable on a scale of hours. Long term changes in CR intensity are caused by shifts in the suns magnetosphere. The "what about the years without" statement is ridiculous. The Agee paper reports on a "possible" disconnect and it is widely recognized that we can't really observe changes in global cloudiness as we would need stationary instruments in space to watch every area daily. So the results of said paper are spurious at best. Furthermore the effect isn't small as you are attempting to claim. Here's a more recent paper for you. Here are the main results: The long-term diversity of life in the sea depends on the sea-level set by plate tectonics and the local supernova rate set by the astrophysics, and on virtually nothing else. The long-term primary productivity of life in the sea – the net growth of photosynthetic microbes – depends on the supernova rate, and on virtually nothing else. Exceptionally close supernovae account for short-lived falls in sea-level during the past 500 million years, long-known to geophysicists but never convincingly explained.. As the geological and astronomical records converge, the match between climate and supernova rates gets better and better, with high rates bringing icy times. "As for the palaeobiology, remarkable connections to the longterm histories of life and the carbon cycle have shown up unbidden (Figs. 20, 21, 22). Biodiversity, CO2 and δ13C all appear so highly sensitive to supernovae in our Galactic neighbourhood that the biosphere seems to contain a reflection of the sky." AGW-0
    0 0
    Moderator Response: TC: Edited to include link.
  31. From the Agee paper: 'This represents a possible observational disconnect, and the update presented here continues to support the need for further research on the GCR-Cloud hypothesis and its possible role in the science of climate change.' Muon you seem to have left something out- The second half of the conclusions... Research on the GCR-cloud correlations must continue, particularly in view of the two physical mechanisms mentioned above (as well as the uncertainty in the reliability of the ISCCP lower troposphere cloudiness to show the proposed correlations). Finally, it is clearly known that other factors can affect mean global cloudiness besides solar variability, due to internal forcing mechanisms on different time scales (such as ENSO).
    0 0
  32. Hmm, the link to the paper didn't post. Here it is again.
    0 0
  33. Cole, Your #30 seem to be referring to the latest from Svensmark. Already noted here. Any guesses as why he's the sole author of this? Agee's result is a clear swing-and-a-miss for Svensmark. The rallying cry 'do more research' is a valid one -- especially as the existing research hasn't done what was claimed.
    0 0
  34. Cole @30, the core of Svensmark's new paper is the correlation he has shown between biodiversity: and his estimate of rates of near by super novas: You can't see the correlation between the two charts? Neither can I. The reason is that Svensmark purports to show a correlation between marine invertebrate biodiversity and his estimated supernova rate. He just assumes, or simply fails to mention, that marine invertebrate biodiversity is a good proxy for biodiversity in general. It is not. It is not even a good proxy for marine biodiversity after the great radiation of fish in the Devonian. So we have this puzzle, why is marine invertebrate biodiversity strongly effected by supernova rates, while all other forms of biodiversity are not? The most likely cause for the apparent correlation is no cause, ie, pure coincidence. This is particularly the case as Svensmark does not even show a correlation with marine invertebrate biodiversity, but only with marine invertebrate biodiversity as normalized for sea level. There is an unusually large change in sea level coincident with with the Permian/Triassic boundary associated with the formation, and then break-up of Pangea. The associated change in sea level is sufficiently large that Svensmark's untested normalization formula is unlikely to properly compensate for the effects of changes in sea level on marine invertebrate biodiversity. That means the correlation Svensmark is trumpeting is almost certainly nothing more than the coincidence of the estimated period of peak local supernova rate with the formation of Pangea. This is particularly the case as the correlation his asserts is poor outside the large excursion at the Permian/Triassic boundary. Unless, of course, Svensmark has stunning new evidence that Galactic Cosmic Rays cause continental drift.
    0 0
  35. Muon, Sure, he's the sole Author, big deal. It passed review and look where it's published. Agee's result is meaningless. We would only need a 2% change in global cloud cover (GCC) to account for the warming trend experienced. As I stated we can't really detect changes in GCC (let alone a mere 2%) as we don't have the proper technology. Agees' result is spurious at best, and the paper even makes it clear that it is only a "possible" disconnect. The CLOUD results didn't prove Svensmark correct as they couldn't make actual clouds. The thing it did prove is the microphysics are defiantly at work. According to Kirby they should have conclusive results within 5 years. The SKS "coffin nails" article is really counting chickens before they hatch. Sure the CLOUD experiment didn't prove Svensmark theory, but the microphysics fit like a glove. Furthermore, if you look at the correlation between CRF and T over the geological eras right up until present it's quite uncanny. Just looking at the last 10-12,000 years Kirkby (2008) rightly notes, “the question of whether, and to what extent, the climate is influenced by solar and cosmic ray variability remains central to our understanding of the anthropogenic contribution to present climate change.” Clearly, carbon dioxide is not the all-important dominating factor in earth’s climatic history. Within the context of the Holocene, the only time CO2 moved in concert with air temperature was over the period of earth’s recovery from the global chill of the Little Ice Age (the past century or so), and it does so then only quite imperfectly. The flux of galactic cosmic rays, on the other hand, appears to have influenced ups and downs in both temperature and precipitation over the entire 10-12 thousand years of the Holocene, making it the prime candidate for “prime determinant” of earth’s climatic state.
    0 0
  36. Tom, "A higher sea level will result in flooding of low inland ar-eas, and increase the total length of coastline and the area of the continental shelves. This results in more heterogeneous habitats in which species can evolve, leading to an increase in diversity, and Miller et al. (2005) offer this as the reason for the development of the three eukaryotic phytoplankton clades (lineages) that dominate the modern ocean. >But the rough correspondence between marine invertebrate diversity and sea level seen in Fig. 19 is plainly not the whole story
    0 0
    Moderator Response:

    [DB] Allegations of misrepresentation are seriously in violation of this site's Comments Policy, just as they are on the SkS FB page.

    Please note that posting comments here at SkS is a privilege, not a right. This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive or off-topic posts. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.

    Finally, please understand that moderation policies are not open for discussion. If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.

  37. Cole#35: You can summarily declare Agee's results 'meaningless' if you like, despite publication in the Journal of the AMetSoc. Perhaps not as prestigious as the Monthly Notices of the RAS, but that really proves nothing. But look at the references in the post: Calgovic, Erlykin x3, Lockwood x2, Pierce... all with negative re-evaluations of the so-called 'looks pretty good' correlation between CR flux and temperatures. Lakin (more than paper) had similar results. Your objection to Agee ("we can't really detect changes in GCC") makes it clear how weak the whole GCR->cloud story really is. We just came through a 50 year high in GCR flux (2009): Where are the clouds? As for the supposedly 'glove-fitting microphysics,' Pierce took that apart at RealClimate. Perhaps you'd be better off with the 'does not fit' defense. Your jump from Kirkby's "... question of whether, and to what extent," to "Clearly, carbon dioxide is not the all-important dominating factor... " in one sentence is stunning. Kirkby's language is the same style as the 'possible disconnect' you found objectionable in Agee. We've gone from GCR->clouds to supernovae->GCR->cooling->mass extinctions. Of course, you've missed the fact that the peak SN frequency on Svensmark's graph is some 50 Myrs before the PTr extinction. You've also ignored what should be the primary objection to the supernova idea: they're not necessarily the source of GCRs. And then there's Montenegro et al 2011, showing that the PTr extinction coincided with increased ocean anoxia and that decreased ccean pH "brought about by the increase in atmospheric CO2 is biologically significant.". Supernovae doing that, too? "you guys deliberately misrepresent papers... " That kind of language usually gets your comments deleted. Please try to come up with more than 'that statement is ludicrous' -- and have a look at the Comments Policy.
    0 0
  38. You've got to love how arguments from authority operate in one direction in the skeptic universe. Suddely because a skeptic's paper is successfully published by the RAS, it is deemed to be flawless, having clearly undergone thorough and utterly rigorous peer-review by experts in the relevant field(s). Yet nearly every relevant climate expert on the planet, and certainly every relevant scientific organisation, agrees that anthropogenic CO2 is causing most of the current rapid warming. Many thousands of papers have been published with this view, all peer-reviewed. Why the disconnect for the 'skeptics'? Bad papers get published. Lets ignore for a moment that the RAS are probably not the greatest repository of scientific expertise on climate, and mention a few other papers. One (McLean et al 2009) was published in GRL even though the authors removed the long-term trend then argued that the short-term variation was causing the long-term trend. Another paper confused degrees with radians at a crucial point. Yet another paper (Spencer and Braswell IIRC) managed to examine a bunch of models and leave out the model runs that demonstrated their hypothesis was critically flawed. So Cole, quite apart from muoncounter's excellent points, which of the following statements do you agree with: (a) There is no such thing as a 'bad' paper and everything that is peer-reviewed is clearly good science. Peer-reviewers are always flawless in their work. (b) Some bad papers get published. These bad papers are either ignored, or subseqiuent responses are published that demonstrate the critical flaws in the reasoning of the author(s). Peer reviewers are human, and despite doing an excellent task in filtering out the very worst papers, occasionally give a pass to a poor paper. This most often happens when the journal's expertise is not ideally matched to the subject matter. [An example of a response is Foster et al 2010, the response to McLean et al 2009] (c) The RAS has never, ever, published a paper subsequently discovered to have been flawed in some way.
    0 0
  39. skywatcher, Cole - And don't forget: (d) A bad paper is published, recognized as such by the majority in the field, and essentially ignored (not cited) by anyone who isn't following the same bad logic. For example: the Gerlich and Tscheuschner paper claiming the 2nd law of thermodynamics (truly silly, now disavowed even by folks such as Fred Singer) was well on its way to that fate when repeated trumpeting by 'skeptics' led to published rebuttals.
    0 0
  40. I'm not simply declaring Agees results as 'meaningless' I'm saying you are misunderstanding them. Agee reported on a 'possible' disconect and even mentioned large uncertainty in the data they used to come to the conclusion. As I've stated many times now, we don't have the technology to detect a 2% change in GCC so your whole answer up untill the microphysics comment is ineffectual. Furthemore, just because we can not detect a two percent change does not mean it isn't happening. As for your Realclimate post, how would you like it if I started relying on blog-science? Maybe I should look up some denier sites and use their arguments? If you want to refute, please use a solid peer-reviewed science. "Your jump from Kirkby's " Kirkby is just a small example on this subject, I was only trying to show you the direct correlation between CRF and T over the Holocene that clearly doesn't exist with CO2. I was simply making a statement in the context of the Holocene, that is very much supported by the data.. If you would really like I could show you a plethera of papers, on this subject spanning the entirety of the geologic eras and show you exactly the same thing. Your statement of the Agee paper being a "swing and a miss" for Svensmark ended up being an own goal for yourself, given what the paper actually said. (-snip-).
    0 0
    Moderator Response: [DB] Off-topic snipped. Again, please review the Comments Policy linked earlier before commenting further.
  41. Cole#40: "I'm not simply declaring Agees results as 'meaningless'." Sorry, what I must have misunderstood is your #30: "So the results of said paper are spurious at best." If you've read anything beyond the abstract of Agee's quite comprehensive review of the current literature, you wouldn't be throwing 'spurious' around: It is clearly evident that the positive trend in previous solar cycles and lower troposphere cloudiness has not continued for the cycle 23-24 QP, which adds to the controversy of the GCR-CCN hypothesis. Not only has the GCR count received a record high level during the cycle 23-24 QP, but the lower troposphere global cloudiness has dropped to a record low level, further challenging the validity of the hypothesis. I suggest you study the remaining references in this post that question the cosmic ray-climate connection. Then there's Love 2011, as noted here and Laken 2011: We find no evidence that widespread variations in cloud cover at any tropospheric level are significantly associated with changes in the TSI, GCR or UV flux, and further conclude that TSI or UV changes occurring during reductions in the GCR flux are not masking a solar-cloud response. "As for your Realclimate post, how would you like it if I started relying on blog-science?" That 'blog-science' was written by Dr. Jeff Pierce, who has published on cloud nucleation mechanisms. Refer also to Pierce and Adams 2009: In our simulations, changes in CCN from changes in cosmic rays during a solar cycle are two orders of magnitude too small to account for the observed changes in cloud properties; consequently, we conclude that the hypothesized effect is too small to play a significant role in current climate change. "the direct correlation between CRF and T over the Holocene that clearly doesn't exist with CO2" Talk about an 'own goal.' Please show us the cosmic ray flux data - not any of those suspicious 'proxies' - for the Holocene. Then refer to numerous articles here showing the excellent correlations between CO2 and temperature.
    0 0
  42. Muon, The Agee results were Spurious, (not genuine, authentic, or true) as per the inability to properly observe GCC changes, and as a result an inability to show proper correlations in either direction. From the paper: 'Research on the GCR-cloud correlations must continue, particularly in view of the two physical mechanisms mentioned above (as well as the uncertainty in the reliability of the ISCCP lower troposphere cloudiness to show the proposed correlations).' The paper itself isn't useless, but your waving it around as proof is. The rest of your papers are just as innefectual for the same reason. Now, let's get back to examining what fits. Bond et al. (2001), who in studying ice-rafted debris in the North Atlantic Ocean determined, in Svensmark’s words, that “over the past 12,000 years, there were many icy intervals like the Little Ice Age” that “alternated with warm phases, of which the most recent were the Medieval Warm Period (roughly AD 900-1300) and the Modern Warm Period (since 1900).” And as Bond’s 10-member team clearly indicates, “over the last 12,000 years virtually every centennial time-scale increase in drift ice documented in our North Atlantic records was tied to a solar minimum:" Parker (1999) noted that the number of sunspots had also doubled over the prior 100 years, and that one consequence of the latter phenomenon would have been “a much more vigorous sun” that was slightly brighter. Parker pointed out that spacecraft measurements suggest that the brightness (B) of the sun varies by an amount ΔB/B = 0.15%, in step with the 11-year magnetic cycle. He then pointed out that during times of much reduced activity of this sort (such as the Maunder Minimum of 1645-1715) and much increased activity (such as the twelfth century Mediaeval Maximum), brightness variations on the order of ΔB/B = 0.5% typically occur, after which he noted the mean temperature (T) of the northern portion of the earth varied by 1 to 2°C in association with these variations in solar activity, stating finally that “we cannot help noting that change in T/T = change in B/B.” . Digging deeper into the subject, Feynman and Ruzmaikin (1999) investigated twentieth century changes in the intensity of cosmic rays incident upon the earth’s magnetopause and their transmission through the magnetosphere to the upper troposphere. This work revealed “the intensity of cosmic rays incident on the magnetopause has decreased markedly during this century” and “the pattern of cosmic ray precipitation through the magnetosphere to the upper troposphere has also changed.” With respect to the first and more basic of these changes, they noted that “at 300 MeV the difference between the proton flux incident on the magnetosphere at the beginning of the century and that incident now is estimated to be a factor of 5 decrease between solar minima at the beginning of the century and recent solar minima,” and that “at 1 GeV the change is a factor of 2.5.” With respect to the second phenomenon, they noted that the part of the troposphere open to cosmic rays of all energies increased by a little over 25 percent and shifted equatorward by about 6.5° of latitude. And with the great decrease in the intensity of cosmic rays incident on earth’s magnetosphere over the twentieth century, one would have expected to see a progressive decrease in the presence of low-level clouds and, therefore, an increase in global air temperature, as has indeed been observed: A number of other pertinent papers also appeared at this time. Black et al. (1999) conducted a high-resolution study of sediments in the southern Caribbean that were deposited over the past 825 years, finding substantial variability of both a decadal and centennial nature, which suggested that such climate regime shifts are a natural aspect of Atlantic variability; and relating these features to other records of climate variability, they concluded that “these shifts may play a role in triggering changes in the frequency and persistence of drought over North America.” Another of their findings was a strong correspondence between the changes in North Atlantic climate and similar changes in 14C production; and they concluded that this finding “suggests that small changes in solar output may influence Atlantic variability on centennial time scales: Van Geel et al. (1999) reviewed what was known at the time about the relationship between variations in the abundances of the cosmogenic isotopes 14C and 10Be and millennial-scale climate oscillations during the Holocene and portions of the last great ice age. This exercise indicated “there is mounting evidence suggesting that the variation in solar activity is a cause for millennial scale climate change,” which is known to operate independently of the glacial-interglacial cycles that are forced by variations in the earth’s orbit about the sun. They also reviewed the evidence for various mechanisms by which the postulated solar-climate connection might be implemented, finally concluding that “the climate system is far more sensitive to small variations in solar activity than generally believed” and that “it could mean that the global temperature fluctuations during the last decades are partly, or completely explained by small changes in solar radiation: Noting that recent research findings in both palaeoecology and solar science “indicate a greater role for solar forcing in Holocene climate change than has previously been recognized,” Solanki et al. (2000) developed a model of the long-term evolution of the sun’s large-scale magnetic field and compared its predictions against two proxy measures of this parameter. The model proved successful in reproducing the observed century-long doubling of the strength of the part of the sun’s magnetic field that reaches out from the sun’s surface into interplanetary space. It also indicated there is a direct connection between the length of the 11-year sunspot cycle and secular variations in solar activity that occur on timescales of centuries, such as the Maunder Minimum of the latter part of the seventeenth century, when sunspots were few in number and earth was in the midst of the Little Ice Age. In discussing their findings, the solar scientists say their modeled reconstruction of the solar magnetic field “provides the major parameter needed to reconstruct the secular variation of the cosmic ray flux impinging on the terrestrial atmosphere,” because, as they continue, a stronger solar magnetic field “more efficiently shields the earth from cosmic rays,” and “cosmic rays affect the total cloud cover of the earth and thus drive the terrestrial climate.” Next, using cosmic ray data recorded by ground-based neutron monitors, global precipitation data from the Climate Predictions Center Merged Analysis of Precipitation project, and estimates of monthly global moisture from the National Centers for Environmental Prediction reanalysis project, Kniveton and Todd (2001) set out to evaluate whether there is empirical evidence to support the hypothesis that solar variability (represented by changes in cosmic ray flux) is linked to climate change (manifested by changes in precipitation and precipitation efficiency) over the period 1979-1999. In doing so, they determined there is “evidence of a statistically strong relationship between cosmic ray flux, precipitation and precipitation efficiency over ocean surfaces at mid to high latitudes,” since variations in both precipitation and precipitation efficiency for mid to high latitudes showed a close relationship in both phase and magnitude with variations in cosmic ray flux, varying 7-9 percent during the solar cycle of the 1980s, while other potential forcing factors were ruled out due to poorer statistical relationships. Carslaw et al. point out that cosmic ray intensity declined by about 15 percent during the last century “owing to an increase in the solar open magnetic flux by more than a factor of 2.” They further report that “this 100-year change in intensity is about the same magnitude as the observed change over the last solar cycle.” In addition, we note that the cosmic ray intensity was already much lower at the start of the twentieth century than it was just after the start of the nineteenth century, when the Esper et al. (2002) record indicates the planet began its nearly two-century-long recovery from the chilly depths of the Little Ice Age. These observations strongly suggest that solar-mediated variations in the intensity of cosmic rays bombarding the earth are indeed responsible for the temperature variations of the past three centuries. They provide a much better fit to the temperature data than do atmospheric CO2 data; and as Carslaw et al. remark, “if the cosmic ray-cloud effect is real, then these long-term changes of cosmic ray intensity could substantially influence climate.” It is this possibility, they say, that makes it “all the more important to understand the cause of the cloudiness variations,” which is basically the message of their essay; i.e., that we must work hard to deepen our understanding of the cosmic ray-cloud connection, as it may well hold the key to resolving what they call this “fiercely debated geophysical phenomenon.” Now I've shown you correlations without having to rely on GCC data (that we can not observe) You guys seem to be grasping at straws trying to dismiss this. Finally to quote the press release from CERN: 'Climate models will need to be substantially revised'
    0 0
  43. Cole#42: I've certainly not been 'waving' Agee around (I mentioned it once before you dragged it back into the discussion after a lag of 5 months). It really doesn't matter whether you accept thier results or not, as there are a number of other references, which up to now you've ignored. But now you summarily dismiss them all as "innefectual" [sic] without any specifics. These papers do not rely on cloud cover measurements alone - and BTW, your claim that it cannot be reliably measured is unsubstantiated. But now your case seems to be made on references from 1999, 2000, 2001, 2002. Let's look at a few (your links above): Kniveton and Todd (published ??): Using neutron data from only Huancayo, Peru (latitude 12 S), they discuss precipitation over oceans between 40S and 80S. Odd. Parker 1999 - (obtained from the blog CO2science? You've quoted their 'review' extensively). No mention of the fact that sunspot cycles have been getting weaker since 1958 - as temperatures continue increasing. Carslaw 2002: This paper appears to have no firm conclusions. It has been proposed that Earth's climate could be affected by changes in cloudiness caused by variations in the intensity of galactic cosmic rays ... Sounds like the same equivocal language you've objected to in Agee. Solanki 2001: This paper is about sunspots and the Maunder and has nothing to do with cosmic rays. was recently discovered that the average strength of this interplanetary field has doubled in the past 100 years. One has to wonder how this was measured over a 100 year interval. Odd that actual measurements show the sun's magnetic field strength decreasing sharply. Face facts: the strongest thing you've got is the CLOUD experiment's preliminary results. Yet you dismissed this ("Kirkby is just a small example"). And until there is an accepted mechanism for these nano-sized cloud nuclei to form actual clouds before they disappear, that's an experimental result lacking a viable explanation. And this thread is about CERN's results, not about 10 year old correlation studies. However, it seems you cannot continue a discussion without resorting to accusation and innuendo ("You guys seem to be grasping at straws"). That is unacceptable (and no, we're not). You've already been advised (twice on this thread) that you must abide by the Comments Policy. Failing that, your behavior thus far has been worthy of this thread's title.
    0 0
  44. Cole's carefully-selected list of papers is a lovely example of cherry-picking to give yourself a confirmation bias. What is missing from the long list of papers showing correlations between various aspects of the Sun's activity and century-millennial scale climate change is a mechanism by which this might work. [and it should be added that the idea that variations in solar output are connected with small changes in climate over the past few millennia is hardly a new one - you'll find detailed discussions in the IPCC AR4 report along with estimates of the magnitude of the forcing, for example in Section 2.7.1.] Which leaves us with a bunch of unknowns, if we are to believe Cole, or those who wish to see a GCR-climate connection: 1: First of all, we need to find a mechanism by which GCR's affect climate - so far proposed and observed nechanisms (e.g. Kirkby) are orders of magnitude too small. 2: We have to explain why palaeoclimate variations do not appear to show very large responses to big solar/GCR variations - a notable example is the Laschamp Anomaly (See this excellent Richard Alley video (after about 40 minutes in). Just before Alley talks about Laschamp, he has this good line:
    ...when you really take this apart you find that when the Sun changes it does seem to show up in the temperature record. It is very reassuring to know that if you change the Sun, the temperature knows this."
    Again, this is not new stuff, sun being a little connected to climate! It's just not as big a player as some would wish. 3: Perhaps most importantly, we have to have an explanation for why a large change in the concentration of powerfully radiatively active gases like CO2 (we've known the since the 19th Century) are not influencing climate, as physics expects them to do. And quite what is producing the observations (e.g. good articles here, or here) of decreased outgoing longwave radiation at GHG-specific wavelengths, and a corresponding increase in downward longwave radiation, also at GHG-specific wavelengths. 4: If you think the physics works OK, you then need an explanation for a hitherto unknown cooling mechanism, perfectly correlated with warming forced from CO2, which is conveniently masking the CO2-driven warming signal, and allows GCRs (whatever their mechanism of operation may be) to modulate climate. When you need multiple unknowns to explain something for which we already have a strong, straightforward observed mechanism, supported by physical and experimental data, you're really grasping at straws.
    0 0
  45. "and BTW, your claim that it cannot be reliably measured is unsubstantiated." From Agee "uncertainty in the reliability of the ISCCP lower troposphere cloudiness to show the proposed correlations" Do you see a disconnect there? Aside from that ask any climate scientist if they can directly measure or observe a 2% change in GCC. This paper finds that solar activity has increased since the Little Ice Age by far more than previously assumed by the IPCC. The paper finds that the Total Solar Irradiance (TSI) has increased since the end of the Little Ice Age (around 1850) by up to 6 times more than assumed by the IPCC. (We all know a more active sun means a stronger magnetosphere) Furthermore, solar activity has slightly declined since 1958 but was running in overdrive before that point. The sun has only recently really started to slow down, and up until recently the magnetosphere (a la Sol), was extremely powerful. "It has been proposed that Earth's climate could be affected by changes in cloudiness caused by variations in the intensity of galactic cosmic rays " This isn't reporting a trend or a disconnect, nor does the paper purport to be able to effectively view changes GCC down to 2% (which is the difference we're talking about here). Solanki 2001, You've missed something, read it again... Straight from the abstract: A part of the Sun's magnetic field reaches out from the surface into interplanetary space, and it was recently discovered that the average strength of this interplanetary field has doubled in the past 100 years. There has hitherto been no clear explanation for this doubling. Here we present a model describing the long-term evolution of the Sun's large-scale magnetic field, which reproduces the doubling of the interplanetary field. The model indicates that there is a direct connection between the length of the sunspot cycle and the secular variations As for the rest I'll have to get back to you, I have practice.
    0 0
  46. Curious that someone who would state the following:
    As for your Realclimate post, how would you like it if I started relying on blog-science? Maybe I should look up some denier sites and use their arguments? If you want to refute, please use a solid peer-reviewed science.
    with such obvious disparagement of "blog science" would then go quote from a blog, and not just any blog, but CO2Science.
    0 0
  47. Adding a #5 to skywatcher's list: 5. You would also need to explain away the characteristics of the current warming trend, which are consistent with greenhouse gas warming (e.g. decreased diurnal temperature variation, decreased seasonal temperature variation, stratospheric cooling & tropospheric warming).
    0 0
  48. "not just any blog, but CO2Science"
    Bingo. That is the question.
    0 0
  49. Now that we're talking about solar reconstructions, we're completely off topic. I'll reply here.
    0 0
  50. Speaking of dodgy blogs, I wonder which of the many skeptic blogs Cole is parroting, when he repeats the exact sentence
    "The paper finds that the Total Solar Irradiance (TSI) has increased since the end of the Little Ice Age (around 1850) by up to 6 times more than assumed by the IPCC."
    . A quick Google search gives quite a few, including but not just: icecap, jo nova, hockeyschtick (and SkS's recent Comments page too of course!). This phrase misrepresents and magnifies the actual Solanki paper's conclusions, ingnoring the uncertainties. Now I don't mind debating sun and climate with real people, but Cole, if you're going to demonstrate the least bit of understanding of the literature, you could at least use your own words, not somebody else's?
    0 0

1  2  Next

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.

The Consensus Project Website


(free to republish)

© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us