Here’s a curious bit of news:

“A paper published this week in Proceedings of the Royal Society Journal A by Dr. Henrik Svensmark of the Danish National Space Center and his colleagues puts forth the claim that cosmic rays are influencing the climate possibly more than CO2.  The theory is that (1) cosmic rays help ionize the outer atmosphere, (2) ions attract water molecules leading to the nucleation of small water clusters, and (3) the water clusters cause clouds to form.  He says that fewer than normal cosmic rays result in fewer than normal clouds and hence less reflection of sunlight from the Earth and thus more global warming. 

The quantity of cosmic rays reaching the Earth is in turn controlled by magnetic activity of the sun.  This may explain the previously noted but not fully understood correlation between sunspots and Earth’s climate.”

My office mate in grad school is now working at the Neils Bohr Institute in Denmark on just this sort of problem. I’ll send him a note and see what he knows…

The issue though isn’t really so much that there might be, or in fact are, other causes for global climate change. The fact that climate change is happening is now a given. And if it’s happening, and our actions can act to slow it down (whether or not we’re the primary cause or not), it seems to be pretty obvious that we should try to do so.

Read the rest here and get links to the original publication: Cosmic Rays and the Climate