Ben Bova: Again, science proves global warming real
By BEN BOVA, Special to the Daily News
June 13, 2004
As we head into the summer's heat and hurricanes, the last crutch propping up those who refuse to believe in global warming has been knocked out from under them.
As the headline in a recent issue of Science magazine put it, "Getting warmer, however you measure it." Pardon the pun, but global warming is a hot issue not only among politicians but among scientists, as well. Many have steadfastly refused to believe that the Earth's climate is heating up, even though measurements from around the globe show that the planet's temperature is steadily rising, so much so that changes in the arrival of spring in high northern latitudes are already noticeable.
If temperatures keep rising, coastal areas (such as most of Florida) could be flooded, tropical disease-carrying insects could invade northward, disastrous hurricanes could become more frequent and more intense, and all the ingredients of a global catastrophe are in the making.
Hogwash, say many who think this entire scenario is some sort of international conspiracy by Third World nations to force the industrialized nations (especially the United States) to cut back on their industrial activities while the poorer nations push as hard as they can to industrialize and overtake them economically. The Kyoto Treaty calls for industrialized nations to severely reduce their outputs of greenhouse gases such as carbon dioxide, while allowing the poorer nations to continue or even increase their greenhouse emissions.
The Bush Administration has been roundly condemned for refusing to agree to the provisions of the Kyoto Treaty. But there is no doubt that cutting down greenhouse emissions means cutting down on industry and transportation, including personal automobile use. It would gravely handicap our economy, perhaps cripple it.
On the other hand, a relatively small but influential nucleus of scientists argue that global warming is an illusion. The disagreement involves temperature measurements of the troposphere, the layer of atmosphere that starts at the Earth's surface and goes up to roughly six miles' height, where the stratosphere begins.
They insist that satellite measurements of temperatures of the upper troposphere show little or no warming trend at all. How, they ask, can the lower troposphere be warming up so rapidly while the upper atmosphere doesn't seem to be affected? After all, in the troposphere the air is constantly mixing, rising and falling. Not like the stratosphere, where very little vertical mixing takes place.
How can you have warming in the lower troposphere without having warming in the upper troposphere? A conundrum, as Winston Churchill might have said, wrapped in a contradiction inside a paradox.
The difference between science and politics is that when politicians have a difference of opinion they continue to argue over it until one side gives up. Sometimes they even resort to war before one side or the other surrenders. Scientists have a different way of settling their differences. They look for more evidence.
Like detectives who have insufficient clues to figure out whodunit, scientists go searching for more and better information to solve their conundrums, contradictions and paradoxes.
For example, for thousands of years most people firmly believed that a heavy object falls faster than a lighter one. A few thought otherwise, among them Galileo Galilei, the first true scientist.
Instead of arguing the point, Galileo toted two objects of different weights to the top of tower. It wasn't the Leaning Tower of Pisa, as legend has it, because although Galileo was born in Pisa, at this time (around 1600) he was living in Venice.
He dropped his two different weights at the same time and had assistants at the bottom of the tower report on which one hit the ground first. They both hit the ground at the same time, and did every time Galileo (or anybody else) repeated the experiment. An argument of some thousands of years' standing was resolved in a few seconds by a simple experiment.
Incidentally, in 1971 Apollo 15 astronaut Dave Scott repeated Galileo's experiment on the airless surface of the Moon. He dropped a hammer and a feather. With no air to impede their fall, both hit the ground at the same instant, while a global television audience watched.
As for global warming, it turns out that the satellite measurements weren't getting the whole story.
Reporting in the British journal Nature, a team of atmospheric scientists from the University of Washington, Seattle, and the National Oceanic and Atmospheric Administration, have shown why the satellite temperature measurements were misleading.
The satellite's measuring instrument was a radiometer that actually measured microwave emissions from the stratosphere, not the upper troposphere. The greenhouse gases from the well-mixed troposphere don't get into the stratosphere very easily. In fact, they act as a sort of lid, so that while the troposphere warms up, the higher levels of the stratosphere can remain cool.
Paradox resolved. The upper troposphere is indeed heating up, just as the lower troposphere — the region we live in — is showing higher temperature readings every decade.
Global greenhouse warming is real.
So what can we do? Cut down on greenhouse emissions, obviously. But how can we do that without wrecking our economy? After all, those greenhouse gases are coming out of the factory smokestacks and automobile exhaust pipes that make us the wealthiest and freest society on Earth.
This is our challenge: to get off the fossil-fuel habit. To move as swiftly as we can to replace oil, natural gas and coal with nuclear, solar, hydrogen and wind power. Not by some government edict that sets draconian goals, but by using the power of the marketplace and the energy of new ideas.
Free man and woman can accomplish seeming miracles. And finding new energy resources will help us in our battle against Middle Eastern terrorism, as well.
Naples resident Ben Bova's latest futuristic novel is "The Silent War." Dr. Bova's Web site address is www.benbova.net
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