To recap: AGW proponents deny that solar variation plays any significant role in climate change. Deniers! However:
"I think the evidence for a link between reconstructions of past climate change and solar activity is too strong to ignore," explains Jasper Kirkby, Spokesperson for the CLOUD experiment. "There are a lot of observations showing that variations of the sun seem to be affecting the climate, but we don’t yet know what the mechanism for this is."
"The aim of CLOUD is to understand whether or not cosmic rays can affect clouds and climate, by studying the microphysical interactions of cosmic rays with aerosols, cloud droplets and ice particles." This is one of the possible mechanisms for solar-climate variability since the solar wind – the stream of charged particles ejected from the sun – varies over time and affects the intensity of the cosmic rays that reach the Earth.
... This is the first time a particle accelerator has been used to study atmospheric and climate science and CLOUD therefore lies at an intersection between several different disciplines.
Also note this from Kirby:
"... Particle physicists are always happier to look at the simplest, most fundamental systems, whereas most atmospheric and climate physicists approach from one of the most complex systems possible – namely the atmosphere and climate."
Data collection will begin later in 2009.
Now this is science. None of that "the debate is over", "the science is settled" BS.