Credibility of scientists on global warming

I reread the article in The New York Times by Elisabeth Rosenthal and Andrew Revkin is titled "Science Panel Says Global Warming Is 'Unequivocal'", and the following quote stood out:

Some authors of the report said that no one could honestly point to any remaining uncertainties as justification for further delay.

“Policy makers paid us to do good science, and now we have very high scientific confidence in this work — this is real, this is real, this is real,” said Richard B. Alley, one of the lead authors and a professor at Pennsylvania State University. “So now act, the ball’s back in your court.”

Yikes! Whatever credibility Prof. Alley might have had, that kind of comment and attitude and disdain for the public and lack of respect for uncertainty sends his credibility down the drain. Incredible.

Just to be very, very clear, any forecast about the future, let alone the state of the world many decades from now or the output of any computer model simply cannot be labeled as "real." The proper label is "speculative."

Maybe this simply highlights the need to separate factual statements from speculative statements, and the fact that the IPCC AR4 Summary for Policymakers failed to clearly make that distinction.

It does not matter how many models you run through a computer, none of them can be categorized as real, at least until the passage of time clearly demonstrates that the model is consistently accurate over an extended period of time.

According to Prof. Alley's web page at the Center for Penn State Ice and Climate Research, his current research interests include Glaciology, ice sheet stability, and paleoclimates from ice cores. That is all good stuff and quite relevant to climate research. I haven't taken the time to review his actual research publications, but I'm a little dubious that even absolute knowledge of Glaciology, ice sheet stability, and paleoclimates from ice cores would enable accurate forecasting of climate change many decades into the future. At this stage I would suggest that such models of the future are highly speculative, far beyond the range of "near certainty" that proponents of the climate change political movement are claiming.

-- Jack Krupansky