No consensus: Warmist Heidi Cullen says that the sun caused past ice ages and warming periods; warmist James Hansen blames CO2

Friedmanpedia / Heidi Cullen

3. "'Nature is like a big complex symphony,' said Cullen, 'and the sun is like the bass drum. Its beat drives everything--from when we had ice ages to when we had warming periods. But now the influence of humans has penetrated so deeply into this symphony that we, us humans, are affecting everyday weather. It's like we are now playing a really loud lead guitar in nature's symphony.'" (P.113)

The 8 Minute Epoch: 65 Million Years with James Hansen « Climate Denial Crock of the Week

In a speech at the University of Oregon, James Hansen, NASA’s chief atmospheric scientist, walks listeners thru the most recent geologic periods

[Note that Hansen says that the CO2 forcing is over 10 times the solar forcing]