A Scafetta & West paper used a model to conclude that the Sun may have been responsible for 25-35% of the warming over the past 30 years. As I discuss here, they had to make some highly questionable assumptions to attribute this much to solar influences:
http://answers.yahoo.com/question/index;_ylt=AoeuTAY_gk.e9tXGWvoGKfwjzKIX;_ylv=3?qid=20071012155438AAM95Xn
and most studies have attributed just 0-10% of the recent warming to the Sun. I'm not aware of any study which has attributed more than 35% of the warming over the past 30 years to the Sun (and I'm pretty sure if one existed, the skeptics would have made me aware of it).
So let's assume Scafetta&West are right, and one-third of the recent warming has been caused by the Sun. What could have caused the other two-thirds, if not human greenhouse gas emissions?
Will the skeptics admit that at least two-thirds of the recent warming is anthropogenic (say 0.15°C/decade rather than 0.2°C/decade)? If not, what caused it?
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