Cosmic Rays Do Not Explain Global Warming

http://www.sciencedaily.com/releases/2008/12/081217075138.htm

ScienceDaily (Dec. 17, 2008) — A new study supports earlier findings by stating that changes in cosmic rays most likely do not contribute to climate change. It is sometimes claimed that changes in radiation from space, so-called galactic cosmic rays, can be one of the causes of global warming. A new study, investigating the effect of cosmic rays on clouds, concludes that the likelihood of this is very small.
...
This result is in line with most other research in the field. As far as Kristjansson knows, no studies have proved a correlation between reduced cosmic rays and reduced cloud formation.

Kristjansson also points out that most research shows no reduction in cosmic rays during the last decades, and that an astronomic explanation of today’s global warming therefore seems very unlikely.