Wednesday, March 25, 2009

Was That a Coors?

In the weeks leading up to Christmas, we had a prolific new member at Dblspeed, as he called himself, wrote long posts with multiple questions that none of us regulars had the time or patience to answer. Then on Christmas day, in the lull between opening packages and fixing dinner, I sat down with my computer and attempted to answer some of his obvious misconceptions. I thought it one of my more brilliant posts. As far as I know, no one ever read it. Not wishing such brilliance to go to waste, I've decided to reprint it here. So here, in a nutshell, is the history of the IPCC:

Once upon a time, back in the 1970's, there were a bunch of scientists who were sitting in the local bar having a brew. As the evening wore on and the effects of beer became more noticeable, scientist #1 turned to scientist #2 and said, "You know, Joe, I've been thinking. We all know that greenhouse gases are what keep our planet warm enough to support life. And we all know that CO2 is a greenhouse gas. And we know that burning fossil fuels releases abnormally high amounts of CO2 into the atmosphere. Do you think there's any chance that all this CO2 we're releasing could heat the planet a tad too much?" Before Joe could answer, scientist #3 leaned over the bar and put in his two cents worth. "Naw, Veronica. It sounds logical, but the facts don't support your little hypothesis. The world isn't getting warmer, it's getting cooler. For all we know, we could be starting into another ice age." Joe looked at them both a moment and then said, "By golly, this sounds like an important question. Maybe we should dig into this a bit and find out for sure!"

Fast forward to the 1980's. The same bunch of scientists are having another drink at the same bar and the same conversation comes up once again. "Hey, Joe, remember when we said we were going to take a look at that greenhouse gas thing? You done any research yet?" Joe answered, "Yeah, I've been doing quite a bit of research and I'm beginning to notice a trend here. Atmospheric CO2 levels are definitely on an upward climb. How about you, Veronica, have you got anything for us?" "Well, I guess I do. I've been studying particles in the atmosphere -- you know, air pollution, volcanic ash, etc., and it looks like some of them have a cooling effect. If we didn't have those floating around, blocking the sun, the climate would be a good deal warmer." Scientist #3 put in his three cents worth, "I've been studying this ice age idea and that was a dead end -- it seems it was those particles that caused the cooling trend, not an imminent ice age. Maybe your hypothesis on global warming has some merit after all, Veronica, but I still think we need more research before we jump to any conclusions." Joe nodded vigorously. "You're absolutely right, Lester, but who is going to put it all together? We need someone who takes my research and your research and Veronica's there and looks at the big picture. We need something like an Intergovernmental Panel on Climate Change. We could ask the top scientists the world over to review our findings and put them together into one comprehensive report every few years. Whatcha think, guys?" They all said, "Here, here," and clinked beer glasses in agreement. And that is how the IPCC was born.

Okay, so I took a little literary license. If you want to know the dry facts without the colorful embellishment, click here.

The IPCC does not do research of its own. It is comprised of hundreds of scientists the world over who study peer-reviewed research done in their field of expertise and look at the implications of that research. They are interested in the big picture, the one you don't get if you only look at individual studies. Their final report goes through an exhaustive review process which, in effect, waters it down a bit (opinions at both ends of the spectrum tend to get washed out in the process). Peer review, by the way, is not a nutritionist reviewing work by an astronomer. It is a physicist reviewing work by a physicist in his own particular field of physics -- it is experts reviewing experts and looking for any possible mistakes. That does not mean infallibility, it just means as accurate as humanly possible. That is why the IPCC reports are taken so seriously -- they represent the work of the thousands of scientists who are doing on-the-ground research. They represent the thousands of scientists who are doing the armchair reviews of the thousands of scientists who are doing on-the-ground research. And they represent thousands of man-hours by the most knowledgeable people on earth who put it all together and present 'the big picture.' When they say a conclusion is 'unequivocal,' that is as close to proof as the science community will ever come.

As for the claim that the IPCC has never done even one study that can be replicated by others, the answer to that is, "True." The IPCC does not do studies, they review studies. And the studies they review are based on empirical data that can be checked by anyone who wishes to spend time examining ice cores in Greenland or measuring CO2 on Mauna Loa. They do create computer models that put the findings into a projection of what we can expect in the future given a variety of scenarios. As the years have gone by, their models have gotten more and more reliable -- for one thing, there is more data for what is currently going on in the world. For another, there is better proxy evidence for what has happened in the past. And for another thing, computers have gotten more sophisticated and our ability to use them has improved vastly. You may see headlines along the lines of "The Arctic is melting faster than models predicted" and that, too, is for several reasons. One is the watering down process that eliminated the extremes in the models but not in real life. Another reason is that the models do not include all positive feedback systems because not enough is known about them and how they interact. And lastly, the IPCC assumed that the world would have listened and started mitigating emissions by now . . . and instead, emissions have increased.

Dblspeed, I don't know where you are, but this beer's for you!

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