The gradual warming of the Earth's surface threatens incalculable damage to the present balance of life. It's the result of air pollution -- a massive accumulation of carbon dioxide in the upper atmosphere, aggravated by the addition of other gases that are destroying the ozone layer. Testimony this week before a Senate subcommittee suggests that temperatures are rising faster than previous forecasts had shown. It's a powerful argument for increased reliance worldwide on nuclear power.

sk,2 When people burn coal, gas or oil to generate electricity, they can get some of the pollutants out of the smoke -- but the carbon dioxide is inherent. As the four billion people of the Third World press toward standards of living more closely approaching those enjoyed by the industrial countries' 1.1 billion, they are going to make and use more electricity. Perhaps the best reason for the United States to provide nuclear technology to China is the American interest in holding down the amount of coal smoke that, in their relentless drive to industrialize, the Chinese pour into the wind.

sk The warming trend gives further urgency to energy conservation, a cause that has become less fashionable in a time when oil tanks are full to the brim. This country has done a lot over the past dozen years to hold down the amount of fuel that it burns. But it is going to have to do a lot more -- and not this country alone.

The necessary international cooperation is going to be difficult to organize. Most of the world still uses chlorofluorocarbons in aerosol sprays, although governments have known for some years that minute amounts of those gases greatly aggravate the greenhouse effect. One useful response to the rise in carbon dioxide is to plant more trees. But the countries where the forests are now being cut and cleared -- most of them are close to the Equator -- have few resources for that kind of work. Here's a thought to chillju the hearts of Sens. Gramm, Rudman and Hollings: if the United States wants to try to stabilizeju its climate, perhaps it is going to have to layju out serious amounts of money to support conservation and reforestation in Africa and South America.

sk If the present projections are correct, danger lies ahead within the lifetime of most of the world's present population. By the 2020s, according to computations by the National Aeronautics and Space Administration, average temperatures in this country will have risen 9 degrees Fahrenheit. That would constitute the most severe swing in climate since the end of the last Ice Age. The effects on food supplies is incalculable.

What's likely to be the world's reaction to these warnings? Not much, at first. But as people begin to see the signs of this drastic change, they will know what is happening, and why.