I am befuddled and I could use some help. One of my students presented me with this theory and I need confirmation/debunking:

Here is the theory: High energy photons and particles bombard the atmosphere (true) which then start particle-antiparticle cascades (true). Some of the cascade particles then cause water-cloud nucleation sites (plausible?). As the Earth moves through different regions of cosmic ray flux (sure), the amount of cloud cover therefore varies.

What I said was not enough to debunk this for him and I might be wrong. I could use some expert help

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Dreamers learn to steer by the stars - Peart

1. What level of school is this?

2. What did you say to him?

3. Did he offer any evidence of cosmic ray flux variation?

4. Did he give any plausible argument against the standard explanations of varying cloud cover?

With regards to whether or not fluctuations in cosmic ray flux (largely correlated with the solar cycle) has any significant impact on recent trends in global climate, see here and here and here.

The other issue is that the actual mechanism for forming clouds via cosmic ray interactions with Earth's atmosphere, what kinds of clouds are formed from such, and how these clouds would impact Earth's radiative energy budget (and on what time scale) remain speculative.

In reply to Spaceman Spiff & new member "tmfpaer"

I am not sure why there is this sudden interest in solar modulation of planetary cloud cover. See the Baud thread “solar cycle 24” for details concerning the hypothesized solar cloud modulating mechanisms (electroscavenging and GCR modulation).

Spaceman Spiff, my comments are included your links. For example see your second here, my comment #99 (made in 2006) which is:

The criticism of Svensmark and colleagues’ search for a solar forcing mechanism is perhaps unfair, as there is significant Palaeoclimatic proxy data that links concurrent changes in cosmogenic isotopes (solar forcing evidence) with ice core and other proxy evidence of rapid climatic changes. There is a smoking gun, so to speak. If the smoking gun data is accepted, the question then becomes how the sun likely causes rapid climatic change events, not if the sun causes rapid climatic change events.

For example the paper: “The role of solar forcing upon climate change” Published 1999.

http://www.gg.rhbnc.ac.uk/elias/teaching/VanGeel.pdf

Last 40 kyrs

Recent Solar Event

Periodicity

Cosmic rays, and their secondaries don't just leave ionization trails in the atmosphere...they leave them in you, me, and everything near the surface of the Earth. Ancient ceramics store the energy as lattice defects, and then relax and release it when heated...thermoluminescence. see:http://www.scienzaonline.com/archeol...cence.htmlYour body repairs most of the cellular damage, but nothing lasts forever. Some of the secondaries release neutrinos which can penetrate and cause some trivial/nontrivial effects throughout the interior of the Earth.

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A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

There is a whole lot of confusion in this thread.

First, the program they are talking about where Cosmic Rays (which they still do not even know what they are! ) are considered as have any effect in 'clouds' was specifically about the Sun fluctuations in relation to the "Heliopause" and how that Magnetic Field protects our solar system more at certain time than others. It protects us more according to the program when the Heliopause is extended out further, thus deflecting more CR's...

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RussT
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Everything is, as it should be, otherwise, it wouldn't be!

And here!

My advice? Move South, not North.

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I am Mugs, of the Alien clan of Usa, Nordamerica, a Terran, of Sol.

Mine: "Perception isn't reality. It's merely an abstraction thereof, and quite often not a very good one at that."

Heinlein's: "Staying young requires the unceasing cultivation of the ability to unlearn old falsehoods." "Freedom begins when you tell Ms. Grundy to go fly a kite."

RussT. Cosmic rays are mostly protons,~89%, with a scattering of helium nuclei,~10%, and 1% the rest of the periodic table in roughly solar system abundances. What they are is moot....where they come from is a little less certain...pete. see:http://www.srl.caltech.edu/personnel...cos_encyc.html

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A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

I am a climate change scientist, and I also am a physicist.

The theory that your student is quoting comes from Henrik Svensmark and various other scientists who discovered that cosmic radiation from supernova can create clouds over the oceans. They do this by interacting with low level gases, mainly from the sea and air.

To back this up they have run an experiment called SKY which so far has shown good results in creating cloud. A new experiment called CLOUD to be run at CERN will confirm the theory.

Everyone seems to want to debunk this theory purely on the basis that it does not accord with the CO2 theory that is very widely held, and particularly the major reason for the existence of the IPCC and every business concern that is involved with climate change.

However, I have reviewed the evidence and I cannot find any serious flaws in it. To call it 'bad astronomy' would not be the case. Even its most ardent opponents have conceded that they could not challenge the methodology.

The theory also helps astronomers know when we pass through the arms of the galaxy, an amazing result, that means that it works 'both' ways. That's the hall mark of a good theory. This theory also uses occams razor at every move, so that one is struck by its integrity at every stage.

Rather than debunking this theory you should be considering examining for yourself, and if you can use it to challenge the current model.

The issue here is which theory is better: CO2 or cosmic ray flux? For many years I have been a follower of CO2 on the basis that despite its numerous flaws (one being that antartica gets cooler than greenland then visa versa across long timescales - this shouldn't happen if its a gas driven causation - and there are lots of others if you check pre-history). However, the cosmic ray theory is much better at explaining the anomalies.

It also explains the paradox of the young faint sun. CO2 gets nowhere here. The work of Nir Shaviv shows how the movement of the earth through the spiral arms of the galaxy influence the Earth's climate over millions of years, proving that CO2 is of a tiny influence compared with cloud cover formation.

So I am afraid if anything is to be debunked, perhaps it is CO2 as a cause of global warming in history. That is of course not to say it isn't responsible for very recent global warming, but it certainly suggests that CO2 is not the only explanation for historical and pre-historical changes in the Earth's climate. And of course CO2 and GHGs particuarly water vapour (again clouds!) are intimately connected to the cosmic ray theory.

When studying the universe, one must consider the whole, and not just the sum of its parts to arrive at the truth. We in the West only break it up into parts, but we fail to put it back together again.

Let's start putting it back together....

It is such a pity that many scientists are going out of their way to debunk this theory, and each time they do it they meet a brick wall of excellent replies based on sound data and experiments.

The CO2 theory by contrast offers nothing in the way of such experiments. It's like school boys concept of the world compared to an explorers!