I believe this is the most important column I've ever written. A controversy rages over global warming. Except for a few blindly obstinate individuals who pathetically look for the rare glacier or ice shelf that has increased in size or who desperately search for recorded warm years in the past, most people recognize that our planet is warming up.
What is controversial is the cause of global warming. Is it due to variation in the sun's activity? That has happened in the past. Is it part of the cycles that have plunged Earth into periodic ice ages or tropical spells? Or is global warming, as a majority of scientists believe, due to human activity?
Unfortunately, many persons' objectivity is distorted by political implications, economic effects, and, frankly, the power of denial.
Life as we know it is possible on this planet because its crust (which conceals a still molten interior) is enveloped in a layer of water and air. The layer of oxygen-containing air that supports life is less than four miles thick. The deeper ocean depths from which all water originates are similarly thin. When we fly cross-country in a jet, the atmosphere outside the plane is too thin to support human life. Yet we can see the ground, see buildings and bridges, and even see traffic on the roads below. This thin, fragile layer of gas that makes life possible is so shallow that if the Earth were six feet in diameter, the air layer would be only the thickness of a business card. Air and water, that thin, make life possible.
In my lifetime—a mere moment in time—the population of the Earth has more than doubled. It's well over six billion now. If I live as long as my maternal grandmother, who lived to be 99, it will be well past seven billion. No large mammal in the history of this planet has ever achieved such numbers.
Homo sapiens has always been wasteful, damaging to the environment, and a spoiler. But when there were only a few million of us, the damage we did was repairable, temporary, and transient.
Does any realistic person really believe that a billion internal combustion engines as well as countless oil refineries and power plants belching the byproducts of spent fossil fuels will not alter our atmosphere? A single major volcanic eruption alters climate, sometimes for years. Can any intelligent, educated person be so obtuse as to believe that no harmful effects are being produced by the billions and billions of people now living in our increasingly technological world?
A recent edition of Newsweek featured a discussion of global warming. A subsequent issue contained many letters both affirming and denying the role of humans as a cause. Some of the letters amazed me. From academia, a professor insisted that livestock were the major cause of atmospheric pollution. Can you believe this? Only two short centuries ago, between 30 and 60 million bison grazed the North American prairies. The grasslands of Africa were grazed by hundreds of millions of ruminants. Today, only remnants of those African animals remain, largely in game preserves and national parks, displaced by exploding human populations.
Mankind's ingenuity, incredible adaptability, remarkable mind, and limitless technology have allowed its population to explode into the billions today. Modern medicine and modern agriculture have greatly decreased human mortality from disease and starvation. Yet, we are still governed as a species by the instincts coded into our DNA. The urge to reproduce is irresistible.
Amazingly, although most of the world's woes are caused by overpopulation, it is rarely blamed by would-be problem-solvers. There is no doubt in my mind that the massive overpopulation of human beings will be abruptly halted sometime in the future, perhaps during this new century. Will it be by famine, disease, nuclear holocaust, or education and technology?
The choice is ours.
Robert M. Miller, DVM, is an author and a cartoonist, speaker, and Veterinary Medicine Practitioner Advisory Board member from Thousand Oaks, Calif. His thoughts in "Mind Over Miller" are drawn from 32 years as a mixed-animal practitioner. Visit his Web site at www.robertmmiller.com.