Hansen, in "Storms of My Grandchildren" said that although "renewables" like solar and wind could theoretically provide up to 80% or more of wold power consumption, he suggested the best way was to replace most coal fired power plants with Gen IV nuclear developed in 1994 and mostly destroyed to appease anti-ANY-nuclear supporters of Clinton.
As for the IPCC;
It is a fact that many climate scientists have been "Erring on the Side of Least Drama":
http://www.skepticalscience.com/climate ... -esld.html From the article:
"Permafrost Melt and Carbon Feedback
The Copenhagen Diagnosis notes that the global warming amplification (feedback) from carbon released as a result of permafrost melting has not been accounted for in any of the IPCC projections. A recent UN Environment Programme report warned that failing to account for this feedback will result in an underestimate of future warming."
They do not want to acknowledge what three groups of tundra scientists said in 2009, that we were at the point of a positive feedback look of tundra methane self release, and what that portends, and what must be done to stop it.
Then this, too;
http://www.sfgate.com/politics/article/ ... php#page-1