There is a difference between skepticism and denial, except when the topic is “anthropogenic global warming.” Then, if you’re skeptical, you’re “in denial” and must be on the payroll of Big Oil.
“Anthropogenic” comes from Greek roots, and means “human-caused.” “Global warming” means a rise in the Earth’s average temperature, leading to the shrinkage of glaciers, a rise in sea level, hotter summers, etc.
The theory holds that humans have, in the past century or two, produced “greenhouse gases” which trap more of the sun’s radiant energy in our atmosphere, thus causing the planet to be warmer than it would be otherwise. There are several such gases, among them water vapor, but the main culprit is carbon dioxide.
Just about everything we burn is a compound of carbon and hydrogen, and when they unite with oxygen, they give off energy while producing water vapor and carbon dioxide. Plants consume carbon dioxide and solar energy, and produce carbon compounds that we can eat or burn for energy.
What perturbs this cycle now is “fossil fuels” like coal and oil, whose combustion may be producing more carbon dioxide than the cycle can handle. Thus the increased carbon dioxide in the atmosphere, which seems to correlate with rising temperatures. But carbon dioxide can come from other sources, like undersea volcanoes and animal respiration, so it’s difficult to be precise.
Further, correlation is not causation. The rooster’s crowing does not make the sun rise. So while the theory of anthropogenic global warming is plausible, there’s no way to prove it – short of finding several Earth-like planets and varying their carbon-dioxide levels, then watching the results. That’s an unlikely experiment.
In a recent report of the International Panel on Climate Change, more than 600 scientists from more than 40 countries all agreed that there is anthropogenic climate change.
But you can have near unanimity among scientists on a given topic and still be wrong. If you had surveyed geologists a century ago, about 100 percent would have agreed that Earth’s continents had been fixed in place since the planet cooled.
In 1912, a German scientist named Alfred Wegener proposed a theory of “continental drift.” Most geologists thought he was crazy, but over time it became the modern theory of “plate tectonics.”
Nearly every physicist of the 19th century believed in “luminiferous ether,” a postulated substance that filled the universe and provided a medium for the vibrations of electro-magnetic radiation. They also believed that time proceeded at the same rate under all circumstances, that the dimensions of an object would not change with its velocity, and that energy could come in as small a quantity as you might desire. Then came quantum mechanics and the special and general theories of relativity, and those theories are the foundations of modern physics.
We don’t have to go that far back. In grade school, I learned about the marvels of modern science, among them DDT, a chemical which would soon eliminate insect-borne disease from our planet with no adverse side-effects. Then came Rachel Carson’s book “Silent Spring,” as well as the discovery of resistant mosquitoes. We’re a lot more careful about pesticides these days, and few if any scientists promote any chemical as a panacea.
Another memory from grade school concerns swamps. Back then, the science textbooks assured us they were nothing but useless breeding grounds for pestilence. Today we call those swamps “wetlands,” and we protect them rather than fill them.
So to say that a vast majority of scientists agrees on something doesn’t make it true, whether it’s luminiferous ether or anthropogenic global warming. The scientific process means our understandings will change as a result of experiment, criticism, discussion and analysis. Anthropogenic global warming may be our best explanation at the moment, but that doesn’t mean it’s true, and it should be questioned and criticized, not taken on faith.
In the meantime, the things we’re supposed to do to combat global warming – reduce emissions, use more renewable energy like wind and solar, improve efficiency, grow more food close to home, walk more and drive less – are all things that would make us a more prosperous, secure and healthy society.
In other words, they’re things we should do anyway, whether global warming results from our emissions or variations in solar radiation. So why can’t we just do them?
Ed Quillen of Salida (ed@cozine.com) is a former newspaper editor whose column appears Tuesday and Sunday.
