There is little doubt that the Earth has been heating up during the last few hundred years. Some, but not all, is probably due to man’s activity. Most people believe that all of it is the result of burning fossil fuels—primarily coal and oil. But science is not done by consensus. We don’t vote to elect a new scientific reality. Let’s start with what we know and take a large view of climate change.
Climate change is a natural process. Long before mankind started burning fossil fuels, the surface temperature of our planet had gone through many temperature fluctuations, sometimes warming up, sometimes cooling down by many more degrees than we are experiencing of late.
During the last Ice Age 18,000 years ago Earth was on average about 12 degrees Fahrenheit colder than it is now and the sea level was about 400 feet lower. Cro-Magnon man lived. He was essentially the same human we are today (though without the iPod) and his kind were not wiped out. On the contrary, there seems to have been a serious human infestation.
Burning fossil fuels surely puts CO2 into the atmosphere. But where do you think all that carbon in coal and oil came from? It came from the atmosphere! That’s right, 300 million years ago when the coal and oil beds were laid down, there was far more CO2 in the atmosphere than there is today and as a result the planet was much warmer.
Maybe global warming is good. If Earth is warming up, more water will be evaporated from the oceans and land. More water in the atmosphere means more clouds and rain. Maybe the rain forests will expand and support new species. Perhaps we can green-up the Sahara. Maybe we can extend the growing seasons by a few weeks and feed more people. On the other hand, maybe the added clouds will reflect more sunlight back into space and cool the planet, perhaps well below current temperatures. Maybe global warming is self-limiting. No one, including the scientists, knows for sure.
What about sea level rise? At present the oceans are rising about 0.2 mm/year. That’s about 0.008 inches per year, or eight-thousandths of an inch per year, about the same rate that Venice, Italy, has been sinking. Except for the plague years, the population of Venice has risen steadily in the last thousand years. Venetians have not suffered, because the land is sinking slowly enough that accommodations can be made. The same will happen if the ocean levels continue to rise at their present pace.
So pick your “golden age.” What temperature is “best” for our planet? And how do you define “best?” Using 50 years of evidence to project hundreds or thousands of years into the future is reckless hubris. Remember when the Earth was flat, and the center of Universe?
The fear of global warming is largely unfounded, though we should not ignore it. It has been pushed by environmental terrorists. “If we scare people, they will vote our way.” Sound familiar? Just because someone says it’s true doesn’t make it true. That’s how we got into Iraq.
I am an environmentalist. I like trees and whales. Watching condos replace farmland is depressing. But I am also a scientist. Scientists are good at separating fact from hype, truth from popular belief, reality from political correctness. I am interested—if not concerned—about global warming. But I know ignorance when I see it. We presently understand too little about the way our global environment works to pass laws or pressure other nations to do so.
Doesn’t it make more sense to understand our climate before we make a bunch of laws trying to regulate it? What we need is more research, narrowly focused on understanding the energetics and feedback mechanisms of our planet. Let’s make it an international priority to really understand the environment and the forces that make it change. Let’s gather the best minds and fund them at the level necessary to unravel our climate. Only then will we be able to make good decisions about what, if anything, we should or can do.
Climate change is serious, but probably not catastrophic as the fear-mongers predict. Maybe, on a global scale, it will turn out to be good. Let’s get the facts first and then act by reason, not ignorance.
David K. Lynch, PhD, is an astrophysicist and planetary scientist. He lives in Topanga.
