I've just been listening to the committee hearings on C-SPAN radio and I have to say, with all due respect to Dr. Hansen as a scientist, he did a very poor job at explaining scientific uncertainty with regards to the NAS report in 2001 about the IPCC. (Note: I may have missed part of the testimony, so I could be wrong.)

There is always uncertainty with science. There are no absolute and exact answers when dealing with climate change. The contrarians and denialists always use this point to their advantage (like Cooney did today) but where Hansen completely missed the mark was in directly addressing this issue of uncertainty. Yes...there's always uncertainty associated with this issue but the degree of uncertainty is the critical issue. It is very clear (in all of the recent NAS and IPCC reports) that the degree of certainty with regard to human-induced climate change is very high (the recent IPCC report quantified this as 90% certainty).

We all make decisions everyday based on somewhat uncertain data (<100% certainty). But that doesn't freeze us from making informed decisions. The same should be true for much larger policy issues such as climate change. It drives me absolutely crazy that people like Hansen couldn't make this point today. This was an excellent opportunity to make this point and it was completely missed.

I'm troubled by two things:
That Congressman Issa was able to put forth the notion that mitigating greenhouse gas emissions would cost the nation 350 billion dollars and that it was repeated as gospel by others. This is the company line: that the cost of solving the problem is worse than the problem itself. It flies in the face of even the White House's own emphasis on investing in technological solutions and finding markets for them, what Connaughton called a "windfall" for California.
That nuclear energy is emissions free.

And for the record, Issa said $350 TRILLION -- i.e., well more than the value of the entire U.S. economy. Where these guys get this stuff is beyond me.

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