At Wired Science Fraser Cain reports on the latest research on global warming and cosmic rays. There is no link:
But T. Sloan from the University of Lancaster and A.W. Wolfendale from Durham University have looked carefully at the evidence and found it unconvincing. They published their results in a new paper called Cosmic Rays and Global Warming. Their research will be presented at the 30th International Cosmic Ray Conference, held in Merida Mexico from July 3 – July 11, 2007.
According to Sloan and Wolfendale, the 2000 paper highlighting the connection between cosmic rays and low-level clouds completely avoids clouds at other altitudes. This is surprising because cosmic ray ionization should increase with altitude. Cosmic rays should be intercepted earlier by the atmosphere and turned into clouds, not down at the lowest altitudes. If cosmic rays were to blame, you would expect the exact opposite, with more high-altitude clouds.