Remember this story from July 20th? The essentials are, that a science team was working on a paper using CERN data that seemed to show a link between cosmic rays and the formation of clouds in earth’s atmosphere. This would be a key finding; cloud cover has a massive impact on temperatures on the earth’s surface. CERN, for its part, was pre-emptively trying to keep scientists from opining about the data, in effect muzzling a science story as it unfolded. That’s a big science no-no.
Well, now the paper has been published in Nature. And it’s big.
The first results from the lab’s CLOUD (“Cosmics Leaving OUtdoor Droplets”) experiment published in Nature today confirm that cosmic rays spur the formation of clouds through ion-induced nucleation. Current thinking posits that half of the Earth’s clouds are formed through nucleation. The paper is entitled Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation.
This has significant implications for climate science because water vapour and clouds play a large role in determining global temperatures. Tiny changes in overall cloud cover can result in relatively large temperature changes.
Unsurprisingly, it’s a politically sensitive topic, as it provides support for a “heliocentric” rather than “anthropogenic” approach to climate change: the sun plays a large role in modulating the quantity of cosmic rays reaching the upper atmosphere of the Earth.
CERN’s director-general Rolf-Dieter Heuer warned his scientists “to present the results clearly but not interpret them”. Readers can judge whether CLOUD’s lead physicist Jasper Kirkby has followed his boss’s warning.
“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.”
Kirkby is quoted in the accompanying CERN press release:
“We’ve found that cosmic rays significantly enhance the formation of aerosol particles in the mid troposphere and above. These aerosols can eventually grow into the seeds for clouds. However, we’ve found that the vapours previously thought to account for all aerosol formation in the lower atmosphere can only account for a small fraction of the observations – even with the enhancement of cosmic rays.”
And then, there’s this.
Climate models will have to be revised, confirms CERN in supporting literature (pdf):
“[I]t is clear that the treatment of aerosol formation in climate models will need to be substantially revised, since all models assume that nucleation is caused by these vapours [sulphuric acid and ammonia] and water alone.
It may be too strong to say that this finding rubbishes previous climate models that didn’t take cosmic ray effects into account. But not by a whole lot, since the models don’t account for cosmic rays. One thing is for sure: Humanity cannot do a thing about cosmic rays or their influence on the atmosphere.