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The results from CERN’s CLOUD (Cosmics Leaving Outdoor Droplets) experiment were awaited eagerly. Many years in preparation, and not without controversy, it has been followed through its funding issues, construction and operation. Earlier this year it was rumoured to have completed its first stage of experiments, and that the results were interesting. It was no one-man crusade, 63 scientists from 17 institutions were involved. It was serious stuff. This is CERN, probably the greatest concentration of scientists on the planet, over 6,000 of them. More incidentally, that contributed to the IPCC report.

We have reported the main scientific findings here.

Even before the results were published in Nature they courted controversy. In a move only made by those inexperienced, or ill-advised, in media matters CERN’s Director General, Rolf-Dieter Heuer, said several weeks before the results were presented that CERN scientists should only describe them and not interpret them as, “that would go immediately into the highly political arena of the climate change debate. One has to make clear that cosmic radiation is only one of many parameters.”

To advise scientists, publically, not to interpret scientific results, especially when the experiment is in an area of great interest, and given that the results were so clear-cut, is extraordinary. Heuer’s statement did nothing to prevent such speculation and only highlighted how important the results were. It was a classic media mistake. In effect it told the world that the results were significant and they did bear on climate science.

When the results did emerge the media were very variable in their reporting of these significant findings. Not many outlets even mentioned the story. Whether this is due to the ‘August Effect’ – a downtime in the media world – or something else is not clear. Certainly many media outlets see climate change as ‘yesterday’s topic.’

To Much, Too Soon

The basic problem with much of the media coverage is that they expected too much. As we have said this is first-stage stuff and not a yes or no judgement on the Cosmic Ray theory. Yet it was taken that way by many. Despite the fact that Cosmic Rays had been shown to have a significant effect on cluster formation (the first stage of cloud seeds) – although those clusters were too small – some took it as a refutation of the whole idea. In so doing they showed double standards in reporting the two aspects of the CERN experiments, the other being cloud formation in the absence of ionising radiation.

The official press release from CERN was only circulated on Thursday morning (the embargo on the story was lifted Wednesday evening London time). It put the investigation of the Cosmic Ray effect as the principle objective of the CLOUD experiment.

CERN stated: “The CLOUD experiment has been designed to study the effect of cosmic rays on the formation of atmospheric aerosols – tiny liquid or solid particles suspended in the atmosphere – under controlled laboratory conditions. Atmospheric aerosols are thought to be responsible for a large fraction of the seeds that form cloud droplets. Understanding the process of aerosol formation is therefore important for understanding the climate.”

The results according to CERN were: “The CLOUD results show that trace vapours assumed until now to account for aerosol formation in the lower atmosphere can explain only a tiny fraction of the observed atmospheric aerosol production. The results also show that ionisation from cosmic rays significantly enhances aerosol formation. Precise measurements such as these are important in achieving a quantitative understanding of cloud formation.”

The results were quite straightforward. Media reporting was not.

According to Nature: “Early results seem to indicate that cosmic rays do cause a change. The high-energy protons seemed to enhance the production of nanometre-sized particles from the gaseous atmosphere by more than a factor of ten. But, [Physicist Jasper] Kirkby adds, those particles are far too small to serve as seeds for clouds. “At the moment, it actually says nothing about a possible cosmic-ray effect on clouds and climate, but it’s a very important first step,” he says.” Nothing to complain about there.

In their report Live Science mixed it all up in a way that resulted in a report that wasn’t entirely clear: “The research doesn’t call into question the basic science of greenhouse gas warming, Kirkby emphasized, but rather refines one facet of the research. Climate models currently predict an average global temperature increase of 3 to 7 degrees Fahrenheit by 2100. The data generated by the CLOUD experiment (CLOUD stands for “Cosmics Leaving Outdoor Droplets”) will feed into global models of aerosol formation, Kirkby said, which in turn will carry into global climate models. “It’s part of the jigsaw puzzle, and you could say it adds to the understanding of the big picture,” he said. “But it in no way disproves the other pieces.” “

Then there was the Guardian which sat on the fence, and I wouldn’t disagree with them: “Our work leaves open the possibility that cosmic rays could influence the climate. However, at this stage, there is absolutely no way we can say that they do,” said Kirkby.

Philip Stier, who heads the Climate Processes Group at Oxford University, said the study was “an experimental leap forward” but that it was too early to speculate on the implications for climate models or the climate in general. He added that the study would inspire more research in this area.”

New Scientist was however more certain: Cosmic Rays “Cannot Explain Global Warming.” Some physicists think galactic cosmic rays – high-energy particles originating from faraway stars – might affect cloud formation. To test their effect on aerosol nucleation, Kirkby’s team fired beams similar to cosmic rays through the chamber and found it increased nucleation between 2 and 10 times. But he points out that an increase in 1 nanometre particles does not necessarily translate into the 50 nanometre needed for cloud formation.

“Other evidence shows that even if cosmic rays do affect the climate, the effect must be small. Changes in the number of cosmic rays hitting the atmosphere due to changes in solar activity cannot explain global warming, as average cosmic ray intensities have been increasing since 1985 even as the world has warmed – the opposite of what should happen if cosmic rays produce climate-cooling clouds.”

To my mind this goes to show how you can ignore caveats in the experimental findings, discard uncertainties and the complexity of the atmosphere, and extrapolate to a grand conclusion. Note that they said that some “physicists” think cosmic rays have an effect.

Scientific American went as far as to say: “Cloud Formation May Be Linked To Cosmic Rays.”

“Something else, as yet unknown”

Now we come to the BBC that had a report from its science correspondent. In the Telegraph James Delingpole said that the BBC report made the research look dull beyond measure. I concur.

To the BBC those who are interested in the idea about Cosmic Rays and climate are “sceptics” and the use of parenthesis is theirs. Does the use of the parenthesis mean that although they have been called sceptics they are not really?

It also missed the point of the research, initially at least, in leading on the uncertainties in the formation of clouds and had the Cosmic Ray section (which CERN said was the main point and which in journalistic terms was far and away the most newsworthy aspect of the story) as the second half. The piece was poorly written, repetitive and included one voice to knock down the Cosmic Rays can form clouds idea, and none to support it. Professor Mike Lockwood said “The result that will get climate change sceptics excited is that they have found that through the influence of sulphuric acid, ionisation can enhance the rate of water droplet growth. Does this mean that cosmic rays can produce cloud? No,” he told BBC News.

The report allows Professor Lockwood to say that in the cloud seeding experiments the fact that the nucleation is at a much lower rate than cloud seeds in the atmosphere is due to “Something else, as yet unknown, is helping enhance the nucleation rates there.” However, when it comes to Cosmic Rays enhancing the nucleation process though producing seeds that are far too small it is game over. There is no unknown factor. “Professor Lockwood says that the air-induced aerosols only grew to about 2 nanometres. To influence incoming or outgoing radiation to Earth, droplets must be of the order of 100 nanometres (nm). The growth rates would be really slow from 2 to 100nm because there simply is not enough sulphuric acid in the atmosphere.”

“There are a great many arguments as to why the cosmic ray cloud effect is not a major driver of climate change and these results do not yet impinge on those arguments,” he said.”

That’s the way. Have an expert say there are many reasons why it doesn’t work but don’t name them. Trust me, I’m an expert. This report marked the story but James Dellingpole is right it was dull and showed no journalistic flair.

This is science at work in a complex field. Preliminary, often contradictory results are common. Over time new certainties often emerge as scientific understanding inches towards a more nuanced better understanding of the climate and its influences. It is not, as some in the media have portrayed the CLOUD story, a battle between sides for and against. The media is often like that, science and the testing of hypothesis is not.