From the S&S archives: Mankind might prevent an ice age, Teller says

WIESBADEN, Germany — A new ice age may come creeping down from the polar regions and put the world in a deep freeze for thousands upon thousands of years, says Dr. Edward Teller, renowned nuclear physicist.

"It may well arrive in 5,000 years unless technology finds a way to prevent it," he says in a deliberate manner, his low voice marked by traces of a Hungarian accent. "It may run its course in 50,000 years. Will any of our descendants still be alive?"

Here he pauses, perhaps to reflect on the question. His bright, gray eyes almost match the gray of his bushy eyebrows, once black, but no longer, after 72 years.

He and Dr. Stanislaw Ulam, while working at the Los Alamos atomic research laboratory in New Mexico in the early 1950s, are credited with being the main minds behind the hydrogen bomb development. Teller will tell you, as if to downplay his part in it, that more than a hundred persons had important roles in it.

But he is not thinking of that now. He appears to be intrigued by the prospect that man might prevent an ice age.

"There most certainly is a chance that we can prevent it," he says. "It would not be an easy undertaking. We may be preventing it right now by burning all this stuff that puts more carbon dioxide into the air which has, I suppose you know the expression, a greenhouse effect."

Teller is a senior research fellow at Stanford University's Hoover Institution. He was in Wiesbaden, Germany, recently to give a commencement speech to Troy State graduates and to visit the school in Goettingen where he taught in the 1930s before fleeing to the U.S. during the rise of Hitler. He was born in Budapest.

Teller calls the greenhouse effect a form of weather modification that is not necessarily desirable.

"The carbon dioxide is quite transparent; it admits sunlight without any difficulty. But the temperature equilibrium of the Earth is due to a balance between energy received from the sun and energy reradiated by the Earth.

"Now, while the carbon dioxide is transparent to the incoming radiation it absorbs a part of the outgoing radiation and therefore it tends to increase the temperature. It is estimated that by the year 2050 the carbon dioxide in the atmosphere will have been doubled compared to what it used to be. And nobody knows, except in the crudest way, what consequences that will have."

But it will almost certainly increase the temperature, particularly near the polar regions, while near the equator it will have a lesser effect, he says. The result will be that the temperature difference between the poles and the equator will be less.

"Now this temperature difference drives the big wind systems," he says, "and therefore the distribution of winds will change and that will have secondary effects which are exceedingly hard to guess. It is by no means obvious that added carbon dioxide will raise the temperature around the world in a uniform manner.

"It will change the weather, although it is not the right way. We do not foresee the consequences."

Another way to alter the weather is to put big mirrors in orbit around the Earth at a distance of maybe a couple of hundred miles, he said.

"They would have to be exceedingly thin and a couple of miles in diameter," he says. "Because otherwise they would be too heavy and too expensive. And I'm talking about a project which optimistically would cost a thousand billion dollars.

"But with the help of these mirrors one can catch more of the sunlight and furthermore bring it to bear on sensitive spots. The structure of the Earth's atmosphere is subject to a great number of instabilities. But these relatively small causes can produce big effects if you know where to reproduce the small causes.

"These mirrors will increase the amount of solar radiation that we receive by a quite modest percentage.

Teller said the mirrors could be aimed at points along the natural cold front that divides Arctic air and the warmer air of lower latitudes. They would be used to regulate where the Arctic air will or will not flow.

"These, when they flow south, give rise to cyclones and to the distribution of precipitation. And if we learn how to do that properly there could be quite an effect in weather modification. So this is an exceedingly important development.

"But you must remember that I did not say that we most certainly can prevent an ice age. I said there most certainly is a chance that we can prevent it."