CERN experiment confirms cosmic ray action


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The global warmists’ dam breaks

A graph they'd prefer you not to notice. Tucked away near the end of online supplementary material, and omitted from the printed CLOUD paper in Nature, it clearly shows how cosmic rays promote the formation of clusters of molecules (“particles”) that in the real atmosphere can grow and seed clouds. 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. 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. 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. The various colours are for clusters of different diameters (in nanometres) as recorded by various instruments. The largest (black) took longer to grow than the smallest (blue). This is Fig. S2c from supplementary online material for J. Kirkby et al., Nature, 476, 429-433, © Nature 2011

Long-anticipated results of the CLOUD experiment at CERN in Geneva appear in tomorrow’s issue of the journal Nature (25 August). The Director General of CERN stirred controversy last month, by saying that the CLOUD team’s report should be politically correct about climate change (see my 17 July post below). The implication was that they should on no account endorse the Danish heresy – Henrik Svensmark’s hypothesis that most of the global warming of the 20th Century can be explained by the reduction in cosmic rays due to livelier solar activity, resulting in less low cloud cover and warmer surface temperatures.

Willy-nilly the results speak for themselves, and it’s no wonder the Director General was fretful.

Jasper Kirkby

Jasper Kirkby of CERN and his 62 co-authors, from 17 institutes in Europe and the USA, announce big effects of pions from an accelerator, which simulate the cosmic rays and ionize the air in the experimental chamber. The pions strongly promote the formation of clusters of sulphuric acid and water molecules – aerosols of the kind that may grow into cloud condensation nuclei on which cloud droplets form. What’s more, there’s a very important clarification of the chemistry involved.

A breach of etiquette

My interest in CLOUD goes back nearly 14 years, to a lecture I gave at CERN about Svensmark’s discovery of the link between cosmic rays and cloudiness. It piqued Kirkby’s curiosity, and both Svensmark and I were among those who helped him to prepare his proposal for CLOUD.

By an unpleasant irony, the only Svensmark contribution acknowledged in the Nature report is the 1997 paper (Svensmark and Friis-Christensen) on which I based my CERN lecture. There’s no mention of the successful experiments in ion chemistry and molecular cluster formation by the Danish team in Copenhagen, Boulby and latterly in Aarhus where they beat CLOUD to the first results obtained using a particle beam (instead of gamma rays and natural cosmic rays) to ionize the air in the experimental chamber – see

What will historians of science make of this breach of scientific etiquette? That Kirkby was cross because Svensmark, losing patience with the long delay in getting approval and funding for CLOUD, took matters into his own hands? Or because Svensmark’s candour about cosmic rays casting doubt on catastrophic man-made global warming frightened the national funding agencies? Or was Kirkby simply doing his best (despite the results) to obey his Director General by slighting all things Danish?

Personal rivalries aside, the important question is what the new CLOUD paper means for the Svensmark hypothesis. Pick your way through the cautious prose and you’ll find this:

Ion-induced nucleation [cosmic ray action] will manifest itself as a steady production of new particles [molecular clusters] that is difficult to isolate in atmospheric observations because of other sources of variability but is nevertheless taking place and could be quite large when averaged globally over the troposphere [the lower atmosphere].”

It’s so transparently favourable to what the Danes have said all along that I’m surprised the warmists’ house magazine Nature is able to publish it, even omitting the telltale graph shown at the start of this post. Added to the already favourable Danish experimental findings, the more detailed CERN result is excellent. Thanks a million, Jasper.

Enlightening chemistry

And in friendlier times we’d be sharing champagne for a fine discovery with CLOUD, that traces of ammonia can increase the production of the sulphuric clusters a thousandfold. It’s highlighted in the report’s title: “Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation” and it was made possible by the more elaborate chemical analysis in the big-team set-up in Geneva. In essence, the ammonia helps to stabilize the molecular clusters.

Although not saying it openly, the CLOUD team implies a put-down for the Danes with this result, repeatedly declaring that without ammonia there’d be little cluster production at low altitudes. But although the Aarhus experimenters did indeed assume the simpler reaction (H2SO4 + H2O), differing results in successive experimental runs made them suspect that varying amounts of trace impurities were present in the air cylinders used to fill their chamber. Now it looks as if a key impurity may have been ammonia. But some members of the CLOUD consortium also favoured (H2SO4 + H2O) and early runs in Geneva used no intentional ammonia. So they’ve little reason to scoff.

In any case, whether the basic chemistry is (H2SO4 + H2O) or (H2SO4 + H2O + NH3) is an academic rather than a practical point. There are always traces of ammonia in the real air, and according to the CLOUD report you need only one molecule in 30 billion. If that helps to oil Svensmark’s climatic motor, it’s good to know, but it calls for no apologies and alters the climatic implications not a jot.

The experiment's logo. The acronym “Cosmics Leaving Outdoor Droplets” always implied strong interest in Svensmark's hypothesis. And the roles of the Galaxy and the Sun are acknowledged.

Technically, CLOUD is a welcome advance on the Danish experiments. Not only is the chemistry wider ranging but molecular clusters as small as 1.7 nanometres in diameter are detectable, compared with 4 nm in Denmark. And the set-up enables the scientists to study the ion chemistry at lower temperatures, corresponding to increasing altitudes in the atmosphere. Cluster production soars as the temperature goes down, until “almost every negative ion gives rise to a new particle” [i.e. molecular cluster]. The lowest temperature reported in the paper is -25 oC. That corresponds to an altitude of 6000 metres, so unless you wish to visualize a rain of cloud-seeding aerosols from on high, it’s not very relevant to Svensmark’s interest in the lowest 3000 metres.

How the warmists built their dam

Shifting from my insider’s perspective on the CLOUD experiment, to see it on the broader canvas of the politicized climate science of the early 21st Century, the chief reaction becomes a weary sigh of relief. Although they never said so, the High Priests of the Inconvenient Truth – in such temples as NASA-GISS, Penn State and the University of East Anglia – always knew that Svensmark’s cosmic ray hypothesis was the principal threat to their sketchy and poorly modelled notions of self-amplifying action of greenhouse gases.

In telling how the obviously large influences of the Sun in previous centuries and millennia could be explained, and in applying the same mechanism to the 20th warming, Svensmark put the alarmist predictions at risk – and with them the billions of dollars flowing from anxious governments into the global warming enterprise.

For the dam that was meant to ward off a growing stream of discoveries coming from the spring in Copenhagen, the foundation was laid on the day after the Danes first announced the link between cosmic rays and clouds at a space conference in Birmingham, England, in 1996. “Scientifically extremely naïve and irresponsible,” Bert Bolin declared, as Chairman of the Intergovernmental Panel on Climate Change.

As several journalists misbehaved by reporting the story from Birmingham, the top priority was to tame the media. The first courses of masonry ensured that anything that Svensmark and his colleagues might say would be ignored or, failing that, be promptly rubbished by a warmist scientist. Posh papers like The Times of London and the New York Times, and posh TV channels like the BBC’s, readily fell into line. Enthusiastically warmist magazines like New Scientist and Scientific American needed no coaching.

Similarly the journals Nature and Science, which in my youth prided themselves on reports that challenged prevailing paradigms, gladly provided cement for higher masonry, to hold the wicked hypothesis in check at the scientific level. Starve Svensmark of funding. Reject his scientific papers but give free rein to anyone who criticizes him. Trivialize the findings in the Holy Writ of the Intergovernmental Panel on Climate Change. None of this is paranoia on my part, but a matter of close personal observation since 1996.

It’s the Sun, stupid!” The story isn’t really about a bunch of naughty Danish physicists. They are just spokesmen for the most luminous agent of climate change. As the Sun was what the warmists really wanted to tame with their dam, they couldn’t do it. And coming to the Danes’ aid, by briefly blasting away many cosmic rays with great puffs of gas, the Sun enabled the team to trace in detail the consequent reduction in cloud seeding and liquid water in clouds. See my post By the way, that research also disposes of a morsel of doubt in the new CLOUD paper, about whether the small specks made by cosmic rays really grow sufficiently to seed cloud droplets.

As knowledge accumulated behind their dam and threatened to overtop it, the warmists had one last course to lay. Paradoxically it was CLOUD. Long delays with this experiment to explore the microchemical mechanism of the Svensmark effect became the chief excuse for deferring any re-evaluation of the Sun’s role in climate change. When the microchemical mechanism was revealed prematurely by the SKY experiment in Copenhagen and published in 2006, the warmists said, “No particle accelerator? That won’t do! Wait for CLOUD.” When the experiment in Aarhus confirmed the mechanism using a particle accelerator they said, “Oh that’s just the Danes again! Wait for CLOUD.”

Well they’ve waited and their dam has failed them.

Hall of Shame

Retracing those 14 years, what if physics had functioned as it is supposed to do? What if CLOUD, quickly approved and funded, had verified the Svensmark effect with all the authority of CERN, in the early 2000s. What if the Intergovernmental Panel on Climate Change had done a responsible job, acknowledging the role of the Sun and curtailing the prophecies of catastrophic warming?

For a start there would have no surprise about the “travesty” that global warming has stopped since the mid-1990s, with the Sun becoming sulky. Vast sums might have been saved on misdirected research and technology, and on climate change fests and wheezes of every kind. The world’s poor and their fragile living environment could have had far more useful help than precautions against warming.

And there would have been less time for so many eminent folk from science, politics, industry, finance, the media and the arts to be taken in by man-made climate catastrophe. (In London, for example, from the Royal Society to the National Theatre.) Sadly for them, in the past ten years they’ve crowded with their warmist badges into a Hall of Shame, like bankers before the crash.


J. Kirkby et al., Nature, 476, 429-433, 2011. The authors list and abstract are available at


H. Svensmark & E. Friis-Christensen, E., J. Atmos. Sol. Terr. Phys., 59, 1225–1232, 1997

Relevant Danish experimental reports since 2006, not cited in the new CLOUD paper

Henrik Svensmark, Jens Olaf Pepke Pedersen, Nigel Marsh, Martin Enghoff and Ulrik Uggerhøj, ‘Experimental Evidence for the Role of Ions in Particle Nucleation under Atmospheric Conditions’, Proceedings of the Royal Society A, Vol. 463, pp. 385–96, 2007 (online release 2006). This was the SKY experiment in a basement in Copenhagen.

Martin Andreas Bødker Enghoff; Jens Olaf Pepke Pedersen; Torsten Bondo, Matthew S. Johnson, Sean Paling and Henrik Svensmark, ‘Evidence for the Role of Ions in Aerosol Nucleation’, Journal of Physical Chemistry A, Vol: 112, pp. 10305-10309, 2008. Experiment in the Boulby deep mine in England.

M.B. Enghoff, J. O. Pepke Pedersen, U. I. Uggerhøj, S. M. Paling, and H. Svensmark, “Aerosol nucleation induced by a high energy particle beam,” Geophysical Research Letters, 38, L09805, 2011. Experiment with an accelerator in Aarhus.