“Maybe the Sun Has Something to Do With It?”

William F. Buckley Jr. delighted in telling the story of how Willmoore Kendall used to infuriate his liberal colleagues on the Yale faculty back in the 1950s (which eventually led Yale to buy out is contract to get rid of him) with simple comments such as the time he was in a faculty meeting where the assembled luminaries were fulminating about McCarthyism.

Kendall took the floor and said, “You know, the janitor Willie asked me the other day, ‘Professor Kendall, is it true there are people trying to overthrow our guvmint?’  ‘Why yes, Willie, it’s true.’  ‘Well, why don’t we lock ‘em up?’  It seems to me, gentlemen, that Willie’s single sentence expresses more wisdom and insight into the matter than anything I’ve heard here today.”

You can see why Yale was so eager to get rid of Kendall.

I’m reminded of this story when contemplating the climate change debate, where every so often a citizen of ordinary common sense will say, “Gee, I think the sun has something to do with it.”  Try saying this in “polite company”—that is, in any assembly of certified climate experts—and watch the denunciation that comes down on you.  The “official” climate models—there’s really no such thing, which is why I use scare quotes—that appear in the periodic Manhattan-phone book size reports of the UN’s Intergovernmental Panel on Climate Change (IPCC) assign a very low weight to variation in the sun’s output, and this makes some sense if you follow the basic physics equations of the greenhouse effect.  I forget the exact figure, but the sun on average produces something like 0.12 watts of radiative “forcing” energy per square meter of the Earth’s surface (compared to about 1.6 watts per square meter for current levels of carbon dioxide), and the epicycles of solar activity aren’t enough to force temperature up or down that much (though there are some compelling studies suggesting it is enough to account for much of what we’ve experienced over the last few hundred years).

But that’s not the end of the solar story; there’s more to the sun than just direct energy radiation.  For almost 20 years a small band of scientists has argued that fluxes in cosmic radiation might have a significant effect on the variation of cloud formation in the Earth’s atmosphere, and, coincidentally, the behavior of clouds is the single largest factor in temperature changes and is the single largest uncertainty in the computer climate models we use to predict future warming from increased greenhouse gases.  (Here’s one account of what is sometimes called “the Svensmark hypothesis,” after Danish physicist Henrik Svensmark.)  This is not exactly rocket science.  Did you ever do or see a cloud chamber experiment in high school that demonstrates how ionizing radiation creates condensation?  Put simply, the role of cosmic radiation in cloud formation could be very significant, but the climate establishment has ignored it as a factor in climate change—until now.

Last week Nature magazine, one of the establishment journals of “mainstream” science, published a letter that might upend the entire climate science debate as we know it.  The letter bears the obscure title, “Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation,” and is written in similarly dense scientific prose, so it’s easy to miss the significance of the contents.  But it was produced by the CERN physics lab in Geneva—the same folks who are bringing us the Large Hadron Collider that is searching for the elusive Higgs boson particle—and lists the names of 63 co-authors, an unusually large number, even for a scientific journal article which often sport more names than a baseball roster.  The CERN people essentially built a very fancy cloud chamber, which they predictably call CLOUD—“Cosmics Leaving Outdoor Droplets.”

The letter is highly technical, of course, but some of the prose in the conclusion is more than tantalizing:

Ion-induced nucleation will manifest itself as a steady production of new particles 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. However, the fraction of these freshly nucleated particles that grow to sufficient sizes to seed cloud droplets, as well as the role of organic vapours in the nucleation and growth processes, remain open questions experimentally. These are important findings for the potential link between galactic cosmic rays and clouds.  (Emphasis added.)

You can read CERN’s press release about the study, where it puts the significance of the study a little more simply:

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 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, and will contribute to a better assessment of the effects of clouds in climate models.

In even plainer English, what this means is that greenhouse gases and other man-made aerosols probably don’t explain observed changes in cloud formation.  The authors of the study are being very cautious about the implications of their study.  The lead author said “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.”  This may be because he was ordered to speak circumspectly.  According to science writer Nigel Calder, Rolf-Dieter Heuer, the director of the CERN lab, told a German newspaper that “I have asked the colleagues to present the results clearly, but not to interpret them. 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.”

Other observers have put the matter even more bluntly: of course more study of this matter is necessary, but all of the climate models will probably need to be revised in the fullness of time.  See the Global Warming Policy Foundation for more.