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What's the link between cosmic rays and climate change?

What the science says...

Select a level... Basic Intermediate Advanced

Cosmic ray counts have increased over the past 50 years, so if they do influence global temperatures, they are having a cooling effect.

Climate Myth...

It's cosmic rays

"When the Sun is active, its magnetic field is better at shielding us against the cosmic rays coming from outer space, before they reach our planet. By regulating the Earth’s cloud cover, the Sun can turn the temperature up and down. ... As the Sun’s magnetism doubled in strength during the 20th century, this natural mechanism may be responsible for a large part of global warming seen then."  (Henrik Svensmark)

At a glance

Space may often be regarded as dark, cold, empty and lifeless but there is plenty going on out there, including the streams of high-energy particles that whizz around at close to the speed of light. These are galactic cosmic rays, discovered by Austrian-American physicist Victor Hess in 1912. Galactic cosmic rays is a catch-all term that includes high-energy particles with sources ranging from the Sun to remnants of ancient supernovae – exploded stars – in other galaxies.

When cosmic rays hit the top of our atmosphere, a highly crowded environment compared to deep space, they interact with the atoms up there producing showers of charged particles known as ions. The ions then head on down towards the surface, where they make up just over ten percent of our typical yearly radiation dose. That's approximately equivalent to three chest x-rays.

The Solar wind protects Earth from cosmic rays and Earth's strong magnetic field in turn shields us from both. In this respect we are fortunate: if you want to find out what happens to a planet that has lost its strong magnetic field, go and take a look at Mars. As a result of these planetary defences, the amount of cosmic rays reaching the lower atmosphere and surface of Earth is minimised.

Direct recording of the cosmic ray flux has been possible since the beginning of the satellite era, since the satellites can carry particle detectors. We therefore have over a half-century worth of data on the changes in the intensity of the flux.

The idea that changes in the cosmic ray flux could drive the observed global warming has a small but determined number of fans. In short, their hypothesis suggests that the ions produced by cosmic rays can 'seed' clouds. That means more cloudiness - and clouds reflect sunlight, reducing the energy reaching Earth's surface. So, it imagines, if there are fewer cosmic rays reaching Earth, there will be fewer clouds, more sunlight reaching the Earth's surface, and thus more global warming. In a sense, this is a variant of the “It's the Sun” argument, because the cosmic ray flux falls when the Sun is in the active phase of its 11-year sunspot cycle and the Solar wind is typically stronger.

In 2017, the Cosmics Leaving Outdoor Droplets (CLOUD) experiment reported in. It had been created to test the link between cosmic rays and climate and was specifically looking for any connection between ions resulting from cosmic rays and cloud-seeding. The CLOUD experiment succeeded in unlocking many of the mysteries of cloud formation and growth in our atmosphere. That greatly improved our understanding of human influences on climate. In particular the study concluded that the effect of changes in cosmic ray flux intensity on the cloud condensation process is small. To quote its authors, it is, "unlikely to be comparable to the effect of large variations in natural primary aerosol emissions" - things like volcanic eruptions, wildfires and so on. So no, cosmic rays do not have much of an effect at all.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Further details

It was at one time hypothesised that galactic cosmic rays (GCRs) may play a part in helping form clouds. A leading proponent of this idea was Danish scientist Henrik Svensmark. If this hypothesis were correct, an increase in the GCR flux, creating an increase in cloud condensation nuclei, would lead to more cloud cover in our lower atmosphere, reflecting more sunlight and resulting in a global cooling effect. Conversely, a decrease in GCR flux would lead to a reduction in cloudiness, warming the planet by letting more sunlight through.

People look at new hypotheses in order to test them. In order to calculate the maximum possible role of GCRs in recent warming, global temperatures have been compared to variations in the GCR flux, as measured by particle detectors aboard satellites and by neutron monitors at the Earth's surface. We'll take a look at some of these studies, for there are many, mostly reaching the same conclusion but with improvements in methodology through time, as always tends to occur in scientific research.

A 2003 paper observed that while there was some correlation between GCR levels and temperature prior to 1970, the correlation breaks down sharply after that point. The analysis concluded that "between 1970 and 1985 the cosmic ray flux, although still behaving similarly to the temperature, in fact lags it and cannot be the cause of its rise. Thus changes in the cosmic ray flux cannot be responsible for more than 15% of the temperature increase" (Krivova & Solanki 2003).

Krivova & Solanki (2003) 

Figure 1: Reconstructed cosmic radiation (solid line before 1952) and directly observed cosmic radiation (solid line after 1952) compared to global temperature (dotted line). All curves have been smoothed by an 11 year running mean (Krivova & Solanki 2003).

Another analysis from the 2000s scrutinises the link between GCRs and cloud cover and finds several discrepancies. As GCR flux shows greater variation in magnitude in high latitudes, one would expect larger changes in cloud cover in polar regions. This, the authors found, was not observed. They also examined the aftermath of the nuclear reactor accident at Chernobyl: the thinking was that if the GCR hypothesis was correct then since the Chernobyl site was a strong source of ionising radiation, some effect on cloud formation might be expected. They found none (Sloan & Wolfendale 2008).

The chance to soundly test the Svensmark hypothesis came up again in a particularly extended Solar minimum (between solar cycles 23 and 24, 2008-2010). This minimum was associated with a record high level of GCR flux, but at the same time, there was a record low level of cloudiness in the lower atmosphere – the bottom ~10 kilometres of the atmosphere where most of the weather occurs. If the GCR/cloud seeding idea was correct, the reverse should have been the case (Agee et al. 2012; fig. 2). Also in 2012, an important review paper, covering the past 35 years of research, concluded, “it is clear that there is no robust evidence of a widespread link between the cosmic ray flux and clouds.” (Laken et al. 2012).

GCR vs. Temp

Figure 2: Annual average GCR counts per minute (blue - note that numbers decrease going up the left vertical axis, because lower GCRs should mean higher temperatures) from the Neutron Monitor Database vs. annual average global surface temperature (red, right vertical axis) from NOAA NCDC, both with second order polynomial fits.

More recently, the Cosmics Leaving Outdoor Droplets (CLOUD) experiment, created to systematically test the link between GCRs and climate, reported in. It had been specifically looking for any connection between ions resulting from GCRs and aerosol nucleation and thus cloud condensation nuclei and cloud formation. The CLOUD experiment succeeded in unlocking many of the mysteries of nucleation and cloud growth in our atmosphere, greatly improving our understanding of human influences on climate. In particular the study concluded that the effect of changes in GCR flux intensity on the cloud condensation process is small and “unlikely to be comparable to the effect of large variations in natural primary aerosol emissions” - things like volcanic eruptions, wildfires etc (Gordon et al. 2017).

This story illustrates nicely how science proceeds. Someone thinks up a hypothesis and it is repeatedly put to the test and is found to be wanting. In turn that leads to further research and important discoveries, providing progressively better understanding into the details of how certain processes work – atmospheric ones in this case. In recent years, Svensmark has been associated with the likes of the Global Warming Policy Foundation, the Heartland Institute and other such organisations who prefer their own version of reality (details at DeSmog). Meanwhile, the science has moved on and left him behind.

Update June 17, 2023 - Based on feedback received, added a concluding paragraph to the at-a-glance section.

Last updated on 18 June 2023 by John Mason. View Archives

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Argument Feedback

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Further reading

A team of scientists from 17 countries have found the most likely origin of galactic cosmic rays - the centres of distant galaxies (Active Galactic Nuclei) powered by supermassive black holes. This discovery is not particularly pertinent to the global warming debate but it is cool :-)

Further viewing

This video published on Nov. 17, 2019 by "Have a think" provides some more and current explanations of why GCRs do not play a role in current global warming.



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Comments 51 to 59 out of 59:

  1. pixeldust#49: "it means scientists are being "censored" and "gagged"" Wow, things must be really slow in deniersville. Since when is the very reasonable request made by Heuer, asking a colleague to be 'clear,' rise to the level of 'censorship'? Why not focus on science questions that arise from these supposed 'results'? For example, the PhysicsWorld article dropped what I consider a rather shocking bit: ... 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 Great news! No accelerator needed. But what does it really mean if the 580 MeV (see PhysicsWorld cited above) accelerated electrons that CLOUD used to simulate GCRs and gamma rays from radioactive sodium produce the same effect? It's supposed to require the higher energy of a GCR (100s of MeV to GeVs) to seed clouds. But Na22 produces 0.5 and 1.27 MeV gamma rays; Na24 (formed by neutron bombardment of stable Na23) produces 1.37 and 2.75 MeV gamma rays. What isotope did they use and what energy gammas resulted? If they used low energy gammas from these sodium isotopes, it means that all cosmic radiation, not just the higher energy GCR component should be making clouds! Solar cosmic rays (mostly protons in the solar wind), which give rise to the ubiquitous muon flux we see at the surface should also produce the same effect. Or it means that the whole concept is total bunk. Bet deniers wouldn't like to hear that. Once again, my apologies to Sondheim: But where are the clouds? Send in the clouds. Well, maybe next year.
  2. Given Musch 2005 I think these GCR guys have an uphill battle. Not only do they have to explain a highly complex mechanism they are going to have to explain why their theory works other times but didn't work in this case. The deck is pretty well stacked against them.
  3. Oh, that slide comes from Alley's AGU A23A lecture. [Source]
  4. Oh no! A new denial meme about to be born: Adriani et al 2011 THE DISCOVERY OF GEOMAGNETICALLY TRAPPED COSMIC-RAY ANTIPROTONS This Letter reports the discovery of an antiproton radiation belt around the Earth. The trapped antiproton energy spectrum in the South Atlantic Anomaly (SAA) region has been measured by the PAMELA experiment for the kinetic energy range 60-750 MeV. So it's anti-matter that's been causing global warming all along. The anti-water that forms from these anti-protons (and those evil positrons) will destroy us all -- anti-rain is clearly the cause of the drought (which could also be called an anti-flood). Be afraid, be very afraid. Bet Svensmark wishes he'd found this.

    [DB] Ah, the Bridge of the Gods has been found!  All that is left is for one to project one's atman into it, then return as the Avatar of Tathagatha, with both raised Aspect and Attributes...

    Of course, that will probably be denied, too.

  5. CERN CLOUD project results are published, discussion @ RC. I suspect they are not all that was hoped for, but I need to read the article.
  6. Dikran, Their experiments produced between ten and a thousand times fewer aerosol particles than found in nature, which basically means that they have not determined the cause of the aerosol formation in our atmosphere. The results were not what they hoped for in that no climatic conclusions could be drawn from their work. But as any good scientists will tell you, this study will inspire more research in the area.
  7. 54, muoncounter, Really, I find your anti-denial of such science to be the antithesis of all that science represents. As Dorothy would tell you, anti-Em may not be the Wicked Witch of the West, but she's no Glinda the Good Witch, either. That, my friend, makes this entire topic a horse of a different anti-color. Or would that be an anti-horse? I suppose I should visit WUWT to be set straight on such issues.
  8. Eric, I completely agree (I try to be a good scientist, but I try to avoid talking to myself as much as possible ;o) as do the RC chaps. The really interesting thing about the CLOUD project as far as the climate debate is concerned is that it is a good example of how science and science funding actually works. Skeptic often say that government agencies will not fund their work, but CLOUD is a big project (see the number of authors) with big funding (about 12MECU IIRC), that aims to investigate the very most basic physical underpinnings of an alternative hypothesis (for which there is only the most circumstantial evidence). It also shows that skeptical hypotheses can and do result in good basic science of general interest to the research community. It also shows that the outcome of an experiment can be very interesting and useful, even if it doesn't provide much support for the working hypothesis (and hence suggest new lines of enquiry or provide support for an existing line etc). A really good experiment is one that has a 50-50 chance of corroborating or refuting an hypothesis as these are the ones that provide the most information about science (in an information theoretic sense). This means we should expect experiments to reject the working hypothesis on a regular basis (a significant minority of experiments); it shows that the research is "sharp".
  9. 58, Dikran, Well said. The only thing that I would add would be that anyone should look at that study and its conclusions and from it recognize that such research is absolutely in its infancy. It is going to develop and progress as it should, but it needs to build its very foundations before it can progress to making many meaningful conclusions about effects on climate. It is not going to challenge current climate science anytime soon (which says nothing about whether it ever will or won't), and skeptics need to avoid trying to use such research, and every resulting paper which will merely represent another baby step in the process, as a debate tool to be used to provide one more "let's wait and see, we don't know enough about clouds and GCRs yet" excuse. Let it just be good science at work.
  10. Sphaerica Indeed, a good example of how not to communicate is Svensmark and Calders book "The Chilling Stars", which essentially attempts to explain every change in (paleo) climate to GCR (slight over-statement there, but only slight) before the fundamental work demosntrating that GCRs actually could affect climate (nevermind whether they did). As a scientist (of sorts) I cringed reading the book, not because the theory is bad, but the lack of perspective which is potentially maximising the height of the fall they are setting themselves up for. I am always very suspicious of any paper that comes with a press release suggesting its findings are contraversial; most often such a paper either (a) doesn't actually support the message of the press release or (b) turns out to be wrong or (c) both. It is much easier to think of examples where this is true than it is for papers that actually did merit controversy.
  11. First it was 'cosmic rays cause clouds;' now its 'Role of sulphuric acid, ammonia and galactic cosmic rays ...' Have the goal posts shifted? And why does the NatureNews headline read Cloud formation may be linked to cosmic rays, which is not at all a justifiable conclusion of the paper? From the Kirkby abstract, We find that atmospherically relevant ammonia mixing ratios of 100 parts per trillion by volume, or less, increase the nucleation rate of sulphuric acid particles more than 100–1,000-fold. Hmm, 100 parts per trillion NH4 is significant now, yet 395 CO2 parts per million is not? Sphaerica#57: You open an interesting possibility. If there is a good witch (helpful to Munchkins everywhere), surely an evil witch (very destructive) could be referred to as an anti-good witch. And the abbreviation for that is AGW!!!
  12. According to Watts, Svensmark has now unveiled a GCR Theory of Everything! There's no need for a link, he's tethered to piece to the homepage so the gang all know the world as we knew it is now over (think I'm exaggerating? Read Watts' piece!) I'm sure you're probably already aware of it, but I thought I'd point it out!...
  13. Sounds like Svensmark has decided to go full Climastrology.
  14. Well, my first thought upon reading Watts' rapturous acclaim was 'so the Astrologers were right, after all'! ;-) If this thing holds up I'd expect triumphalism from that quarter, too, and not just our contrarian friends. (Just think of the woooo impact of Quantum Mechanics. As Terry Pratchett says 'It's Quantum'!) Let's face it, if it doesn't hold up, we'll get triumphalism anyway (in fact, that's what Watts comments thread is full of, with the occasional brave soul pointing out that he/she thought they were all supposed to be, um, 'skeptical'!) Yet again: hundreds of papers arising from years of hard-won science that builds on findings dating back over a century - it's all BS mate, crap! Particularly all that dodgy paleo crap and expecting us to believe minute trace gases make any difference. But give 'em one paper based on paleo reconstructions of the impact of rays from the outer reaches of the universe - doubts, who has doubts? Hypocrisy and just plain silliness I can identify; but me, I make no claims to being able to assess the science, hence my bringing it up here.
  15. Svensmark must have read 'Star-Begotten' by HG Wells. However, Watts can in no way take the role of the 'quiet little man'. ‘Those cosmic rays of yours,’ he said. ‘They are the most difficult part of your story. They aren’t radiations. They aren’t protons. What are they? They go sleeting through the universe incessantly, day and night, going from nowhere to nowhere. For the life of me I find that hard to imagine.’ ‘They must come from somewhere,’ said a quiet little man with an air of producing a very special contribution to the discussion. And when all other arguments against AGW have failed, they invoke a mystery. ‘And so, having eliminated everything else,’ said the barrister, ‘you lay the burden of change and mutation — and in fact all the responsibility for evolution — on those little cosmic rays! Countless myriads fly by and miss. Then one hits — Ping! Ping!— and we get a double-headed calf or a superman.’
  16. My first censorship and I give credit to the great work you have been doing at Skeptical Science. I thought the view that SKS are propagandists might interest the group. Attempting to show GSR's would actually have been a cooling effect I believe is what did not go well with him. • Jonathan_Duhamel Note to renewableguy: I have deleted your comment on GCR because it is irrelevant and misleading, and shows that neither you nor the propagandists at skeptical science have read the paper. Had you read the paper you would see the explanation. renewableguy Jon I doubt very much there is a connection between life thriving on earth and galactic cosmic rays. Misleading is actually wrong and it shouldn't be your opinion alone to determine that. I presented an article based on several data sources explaining their point on GCR's. Proganda would be based on countering the truth with possibly false information. You are showing yourself to be using strong arm tactics unnecessarily. If you are interested in a fair presentation of both sides then put my article back up. If you only want to present one side, then by all means keep my post off. Skeptical science bases their postings on the current science.And yet you base your articles on the latest denial of AGW in the right wing circulation of entirely wrong and false media hype. The scientist refuted this false information very quickly. Your conclusion of medieval warming period was refuted by the very scientist that wrote it. This a true account of what has happened. Unless you would like to use your editorial power to rewrite that history.

  17. A couple of notes on Svensmark's latest. Let's start with the worst news: Origin of Cosmic Rays Not What Was Thought Results announced at nearly the same time as Svensmark's paper show that gamma ray bursts from supernovae are not associated with the expected neutrino flux. This calls into question the entire mechanism of cosmic ray origin underlying Svensmark's paper - as GRBs are clearly connected with supernovae. From the MNRAS announcement of Svensmark's paper: To obtain this result on the variety of life, or biodiversity, [Svensmark] followed the changing fortunes of the best-recorded fossils. These are from invertebrate animals in the sea, such as shrimps and octopuses, or the extinct trilobites and ammonites. So from the start, its clear that we're talking about life in the oceans only. They tended to be richest in their variety when continents were drifting apart and sea levels were high and less varied when the land masses gathered 250 million years ago into the supercontinent called Pangaea and the sea-level was lower. It's been known for quite some time that biodiversity diminished as shallow seas dried up during the formation of Pangaea. But this geophysical effect was not the whole story. When it is removed from the record of biodiversity, what remains corresponds closely to the changing rate of nearby stellar explosions, with the variety of life being greatest when supernovae are plentiful. When the primary driver is removed, what remains is a residual. Any detectable signal from this point forward is thus no more than a secondary mechanism and may in fact be contaminated with unexplained residuals from the primary. A likely reason, according to Prof. Svensmark, is that the cold climate associated with high supernova rates brings a greater variety of habitats between polar and equatorial regions, while the associated stresses of life prevent the ecosystems becoming too set in their ways. Svensmark's self-described 'innovation' is that cosmic rays from close supernovae cool so extensively that they cause glaciation and the associated sea level drop. This speculative leap requires acceptance of his as yet unsubstantiated model (cosmic ray ionization -> clouds -> observable cooling). However, there's a hidden contradiction here: supernovae (and the resulting colder climates) did not 'help life to thrive' (as claimed); colder climates produced greater environmental stress, resulting in higher extinction rates. The highest supernova frequency shown by Svensmark is a broad band from 300-250 million years bp, during the Permian. At the end of this period (252 MYBP), the greatest mass extinction event known on Earth occurred. Does 'thriving' equate to mass extinction? Or was it the end of the 50 million years of stressful cosmic ray-induced cold climate that caused the extinction? Is it chicken or egg? It is interesting to note as well that Svensmark is the sole author on this paper. But they laughed at Galileo... BTW, one aspect of propaganda is that it is "repeated and dispersed over a wide variety of media in order to create the desired result in audience attitudes." Searching "svensmark cosmic rays life" returns a 'wide variety of media' indeed: WUWT, Nigel Calder, The Register, The Daily Mail, etc.
    Response: [Riccardo] link fixed
  18. muoncounter: But what about the Battlestar Gallactica effect?
  19. Move over, galactic cosmic rays! Bring on the 'blazars:' ... black holes can emit high-energy gamma rays and are then called blazars. ... This particular radiation interacts with the optical light that is emitted by galaxies, transforming it into the elementary particles electrons and positrons. Initially, these elementary particles move almost at the speed of light. But as they are slowed down by the ambient diffuse gas, their energy is converted into heat, just like in other braking processes. The process of converting electron/positron kinetic energy into heat by 'braking' seems a bit mysterious. But have no doubt, the 'ABC' crowd will spin this into their next version of 'the answer.'
  20. Rawls writes on WUWT: "In effect they are claiming that you can’t heat a pot of water by turning the burner to maximum and leaving it there, that you have to keep turning the flame up to get continued warming, an un-scientific absurdity that I have been writing about for several years (most recently in my post about Isaac Held’s bogus 2-box model of ocean equilibration)." Does someone have a precise explanation of what Rawls apparently misunderstands about the science when making this analogy? My impressions are as follows (I have a mechanical engineering degree with a loose focus on the thermal side of things, so I have better than a layman's understanding of heat transfer, but I am no more than a casual student of climate science): 1) When you heat a pot of water, it DOES stop getting hotter when the water reaches 100 deg C, as the temperature of liquid water cannot physically go above that. More importantly, the reason why the water can keep absorbing heat without any increase in temperature is that it is giving up thermal energy at the same rate that it is being absorbed, in the form of the latent heat of vaporization of the water vapor that escapes the pot! When that vapor touches something cooler and condenses, it will pass that latent heat of vaporization back to whatever it touches. If you do happen to increase the flame level, one thing that you will notice is that the steam escapes more quickly, to account for the fact that the water temperature can't go up any more, and a thermal energy balance must nonetheless be maintained. 2) Even if Rawls had picked an simpler example without physical phase change, like heating an empty pot, that too would eventually reach an equilibrium temperature for a given flame level. This would happen because the higher the temperature of the pot, the more heat it gives off by convection. Thus, when the rate of convection of heat from the surfaces of the pot into the surrounding air became equal to the forced rate of heat transfer into the pot from the flame, the temperature of the pot would stop rising. So his basic premise, that it would be absurd to think you have to keep increasing the flame level to raise the temperature of something you are heating, is false: eventually the object stops getting hotter, and you DO have to raise the flame level! 3) Giving Rawls the benefit of the doubt that he understands the law of conservation of thermal energy within a control volume, he seems to be implying that climate scientists have failed to account for the Earth's ability to respond relatively quickly (i.e., in significantly less time than 50 years) to whatever amount of forcing resulted from the increase in TSI that occurred before it remained generally flat 50 years ago, and reaching an equilibrium vis-a-vis that forcing long before now, so that effects of that forcing delayed by 50 years cannot explain the current warming. Rawls' attack doesn't pass my smell test, and I trust that climate scientists are in fact very familiar with and have accounted for the lag between a step or ramp up in TSI and its observed effects on global temperatures. Can somebody address that succinctly, in a way that would help somebody who is not necessarily so scientifically inclined to understand why they should trust that scientists have taken any "lag" effect into account?
  21. For those interested, I looked back and now see that comment 12 above addresses the denier argument that the effects of TSI could be lagging, and includes a hyperlink to a more detailed explanation.
  22. Update 2012: RealClimate posted "A review of cosmic rays and climate: a cluttered story of little success."
  23. There are quite visible correlations (link to image) between the two curves. The cycle duration is 11 years. This is the solar spot observation periodicity as known for several hundreds of years already. Even the well known fact that the solar cycle that should have started at about the millenium change came a bit late is seemingly reflected in the curves.

  24. IIUC, you are denying the scientific hypothesis that there is a correlation between sunspot numbers and climate on earth.  Your argument appears to be that because this hypothesis doesn't account for all global warming, that it doesn't account for any global warming.  That is both unscientific and fallacious reasoning.

    We have history that provides strong evidence that this hypothesis is correct.  The Maunder Minimum and the Little Ice Age being most significant.  Still, it is true that we do not completely understand the action mechiism.

    You are correct to point out that this correlation broke in the second half of the 20th century.  However, since it has been so strong historically, it is more reasonable from a scientific point of view to try to figure out why the correlation broke than to use this fact to try to prove that the hypothesis is false.

    Might I suggest one possible cause which is CFCs.  It is now belived that CFCs had a stronger effect on global warming than was once thought and their concentration in the atmosphere, taken as a factor (possibly with a delay in time) allong with the sunspot number as a proxy for solar activity in factor analysis might yield a reasonable answer to the question.

  25. JRT256: Firstly sun-spot numbers are correlated with total solar irradiance (TSI) as well as cosmic rays.  So a correllation between sunspot numbers and climate does not necessarily involve cosmic rays as the causal mechanism.

    Secondly, a link was provided to the "body of scientific research has determined that GCRs are actually not very effective at seeding clouds."  (i.e. the advanced version of the article).  The cosmic ray theory is not unlikely to be correct because it doesn't explain all warming, but because of the scientific research that has been performed has identified several problems with the causal mechanism,  If you want to discuss the details of any of the papers mentioned, I'm sure there will be plenty of contributors willing to discuss them with you.

    "it is more reasonable from a scientific point of view to try to figure out why the correlation broke than to use this fact to try to prove that the hypothesis is false."

    Actually, the most plausible theory is that there is more than one forcing that affects climate; changes in total solar irradiance and the rise in greenhouse gasses explains the breakdown in the correlation pretty well.  However, proving hypotheses to be incorrect is a fundamental part of scientific method.  Ruling out hypotheses is a good a way of finding out why the correllation broke down as any.

    Lastly, as a word of advice, if you want to have a discussion of science, starting by using phrases such as "That is both unscientific and fallacious reasoning." when you yourself obviously have not understand the argument put forward in the article is unlikely to be conducive to constructive dialogue.  Note I have taken pains to reply in a rather more civil manner.

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