"Solar Effects on Earth's Climate Reference
Bard, E. and Frank, M. 2006. Climate change and solar variability: What's new under the sun? Earth and Planetary Science Letters 248: 1-14.
.........What was done
The authors review what is known, and unknown, about solar variability and its effects on earth's climate, focusing on the past few decades, the past few centuries, the entire Holocene, and orbital timescales.
......Taken together, these several observations leave little need to invoke the historical increase in anthropogenic CO2 emissions as the primary cause of modern warming. In fact, they leave no such need at all, as solar influences appear to be sufficient to explain the bulk of the increase in temperature. Nevertheless, much more work is needed to clarify the specific mechanisms by which the solar-induced warming is accomplished."
the whole thing HERE
Brett mentions in comments a channel4 documentary on this."RESEARCH said to prove that greenhouse gases cause climate change has been condemned as a sham by UK scientists...."
News.com item here: