Solar variability and clouds - Discussion session 3c

Satellite observations have recently revealed a surprising imprint of the 1 1-year solar cycle on global low cloud cover. The cloud data suggest a corr elation with the intensity of galactic cosmic rays. If this apparent connec tion between cosmic rays and clouds is real, variations of the cosmic ray f lux caused by long-term changes in the solar wind could have a significant influence on the global energy radiation budget and the climate. However a direct link between cosmic rays and clouds has not been unambiguously estab lished and, moreover, the microphysical mechanism is poorly understood. New experiments are being planned to find out whether cosmic rays can affect c loud formation, and if so how.