Review of "Cosmic Rays and Climate"
by Nir J. Shaviv, 2006-04-28

The intensity of cosmic rays and temperature correlate well over time scales of hundreds of millions of years. Temperatures on earth are 10 degrees centigrate colder when the solar system passes through a spiral arm of the milky way galaxy. Cosmic rays are about ten times as intense in the spiral arms.

Data on cloud cover obtained by satellite instruments show a correlation between cosmic ray intensity and cloud cover from 1980 to 2003.

When the sun is more active, less cosmic rays reach the earth's atmosphere. Increased solar activity could explain more than half of the global warming occurring in the twentieth century.

Source: http://www.sciencebits.com/CosmicRaysClimate

Best wishes,
Alan Detwiler: rural resident, gardener, and advocate of self sufficiency and resilient living. Bio at http://www.smashwords.com/profile/view/alandetwiler