Many people seem to feel strongly that global warming is inevitable. But how can they possibly know?
To have an informed opinion on global warming you'd need extensive knowledge of a wide range of technical subjects. You have to know the historical patterns of temperature change going back hundreds of thousands of years. To be able to calculate how much methane might be released from the ocean floor by warmer water temperatures. To factor in the earth's orbital patterns and how solar variation affects planetary temperatures. To understand the breakdown rate of carbon dioxide and carbon monoxide. To be able to calculate exactly how much the depletion of the ozone layer will increase water vapor in the atmosphere, and how the increased water vapor will affect temperatures. To understand how the height of the troposphere changes the emission of infrared radiation. (That last bit was lifted from Wikipedia; don't worry, I don't understand it either.)
Any of you who understand all these things and have pondered long on how they will all interact over the next hundred years, please feel free to speak up. Otherwise, please hold your peace.
Yes, the average temperature has increase 1.3 degrees Fahrenheit over the past 100 years. Yes, Arctic ice is retreating. And yes, human beings are burning fossil fuels and clearing natural vegetation at heretofore unseen rates. And it does seem logical that these activities would have an effect on the atmosphere. This post isn't a brief against the hypothesis of global warming. (I actually think it would be a good idea to cut down on carbon emissions for a number of reasons.) It's merely a brief against people with strong opinions about subjects they can't possibly understand. Most of us can't predict the weather a week from now. We can look at the forecast. But we'd be hard pressed to come up with one on our own.
Predicting global warming is essentially predicting the weather 20, 40, or 100 years in the future.
Al Gore, by the way, is not a scientific expert either. He is a politician with an agenda. His movie, An Inconvenient Truth, was anything but truthful. One example: in order to show how water is being mismanaged, he showed a film of a flowing river, then showed how by the next year it had run dry. He never mentioned that the reason the river had gone dry was because a dam had been built upstream during the previous year. (Perhaps he was too busy turning on the lights in his mansion in Tennessee, which has ten times the carbon footprint of the average American house.)
The global warming debate is a little reminiscent of the controversy years ago over whether the Air Force needed the B2 bomber. Many people seemed to have a strong opinion on the subject, yet very few were scientists, let alone armaments experts. Sometimes these people would be able to quote an expert who leaned their way; yet there were experts on both sides of this issue, and it seemed to me that most of these people would simply pick an expert who leaned their way. (And yes, almost all the people that I knew with strong opinions were liberals.)
It's also a bit like predicting the direction of the stock market, whose path is determined by a myriad of factors, all of which interact in infinitely complex ways, making reliable prediction basically impossible. One thing I learned after twelve years on Wall Street was that the surer a person was of the direction of the market, the more full of it he was.
The same might be said of opinions on global warming. Our planet has gone through five Ice Ages (and subsequent warming periods) in the past 800,000 years. No one completely understands why they occurred. And no one, least of all nonscientists, should feel certain about where we're headed in the future.
It's not a crime to say, "I don't know."
I once heard that true wisdom was knowing what you don't know.
As good a definition as any.