The '''Svensmark hypothesis''' posits that [[cosmic rays]] reaching the Earth's atmosphere create [[cloud condensation nuclei]] by knocking [[electron]]s out of gas molecules in the atmosphere. [http://calderup.wordpress.com/category/3b-the-svensmark-hypothesis/]
* "According to the hypothesis, then, less [[cosmic radiation]] would mean less cloud formation and, ultimately, warmer temperatures – precisely what was observed during the 20th century." [http://www.foxnews.com/story/0,2933,220341,00.html]
* "The Svensmark hypothesis is that when the [[solar wind]] is weak, more cosmic rays penetrate to Earth. That creates more [[charged particles]] in the atmosphere, which in turn induces more clouds to form, cooling the climate." [http://news.bbc.co.uk/2/hi/7327393.stm]