TCS: Tech Central Station - Let Them Confess Their Faith
It wasn't long after I became a research scientist that I learned that scientists aren't the unbiased, impartial seekers of truth I always thought they were. Scientists have their own agendas, philosophies, pre-conceived notions, and pet theories. These views end up influencing their science. Nowhere does this have a greater impact on the science than in global warming theory.Exactly! Scientists are humans after all and it's impossible to be perfectly objective. I wish scientists would acknowledge this instead of acting like the Sophists that Socrates debated.
When confronted with a new, policy-relevant science problem, there are always scientists that will immediately rush to judgment about a "possible" environmental catastrophe. In the 1970's it was an impending ice age. In the late 1980's it was inflated global warming predictions. Most recently both extremes have morphed into the possibility that global warming will actually cause an ice age for Europe. In an age when popular culture helps to blur the line between science fiction and reality, our imaginations are fired by the thought of an ice sheet advancing on a city, or unexplained increases in severe weather.Yep. When I saw the previews for the "The Day After Tomorrow," I rolled my eyes and thought, "Great. More global warming propaganda from those global science 'experts' in Hollywood."
On February 4 I testified in a congressional hearing that was held to explore the role that science plays in public policy formulation. I tried to explain that science always involves assumptions, and so scientific conclusions are only valid if the assumptions hold up. And there are always additional, unstated assumptions that the scientist isn't even aware of!
For a complex problem like climate change, assumptions abound. Early in the climate modeling days, confidence was high as physicists used to working on well-defined problems with a limited number of variables thought they had the answer. We meteorologists (by training) were always more skeptical because we understood how complex weather is. Enter the scientist "heavy hitters" that are savvy public speakers, maybe a Nobel laureate in some unrelated field of science, all having strong opinions about what the government should be doing to help "save the Earth" and you have a recipe for bad policy. Now, the climate modelers are learning how complex the climate system really is (surprise!). The tendency for scientists to rush to judgment isn't the fault of science -- it's just human nature.
Yes, it never fails for proponents of controversial theories to round up a bunch of Nobel Laureates or members of the National Academy of Sciences that support their cause. Never mind that molecular biologists (I include myself here) don't know diddly squat about climate modeling. But some of them may be very persuasive speakers (I include my mentor here) and could sell snowshoes to a tourist in Hawaii.
Even though I love details, I also am constantly striving to understand the "big picture." We have pretty high confidence that increasing carbon dioxide concentrations have a warming tendency. The Earth's natural greenhouse effect, mostly due to water vapor, keeps the Earth's surface and lower atmosphere warmer that it would otherwise be, and the extra carbon dioxide adds to this effect. But about 75% of that surface warming is never realized. All that water vapor represents huge amounts of heat that have been removed from the surface of the Earth, in a very real sense "air-conditioning" it, keeping the surface over 100 deg. F cooler than if weather systems did not exist. All weather systems act to redistribute heat, carrying it from where there is more to where there is less…the energy contrast is what drives them. So, the real question is, how will weather systems adjust to the warming tendency? Will they change their cloudiness or precipitation processes in such a way to amplify (positive feedback) the warming or suppress it (negative feedback)?Amen to that. Before bodies like the U.N. start drafting drastic proposals like the Kyoto Treaty, which could do severe damage to the international economy, they should make sure the science behind global warming is sound. I don't think we're there yet.
Our knowledge in this area of precipitation and cloud microphysics (which control the equilibrium amount of water vapor in the atmosphere) is so meager, that I would argue that it is a matter of faith to believe that the Earth will respond by amplifying the warming tendency. If the response is simply benign, then about 2 deg. F warming is about all we'll have to contend with in the next 100 years or so. But in the meantime, I wish all those global warming extremists would simply confess their faith -- and stop giving science a bad name.
Update: Curse Google ads! So I write a post on how the dangers of global warming are exaggerated and Google ads displays ads for environmental newsletters and "one solution to stop global warming." YEEEARGH!