Science: Ocean Frontier

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The problem is not just academic. If the oceans are to be used for the disposal of radioactive wastes, oceanographers must find stagnant basins where wastes can be dumped with assurance that they will stay out of circulation until their activity has been stilled by time. Warns Iselin: "If you louse up the ocean with atomic waste, you louse it up for thousands of years. The British pump stuff into the Irish Sea, which can take a lot. But one day . . ."

New Ice Age? Oceanographers believe that man is approaching the point where he can try large-scale experiments on the ocean. Not all of them like this prospect; they feel that tinkering with the ocean without sufficient knowledge may be extremely dangerous. They are aghast at the project much discussed by the Russians, of using atomic energy to clear the Arctic Ocean of ice to help Siberian sea transport. Dr. Maurice Ewing of Columbia University's Lament Geological Observatory believes that the Northern Hemisphere's comparative freedom from continental glaciers is due to Arctic ice. Winds blowing off the Arctic Ocean are now dry, but if the ice were removed, they would become moist, dropping snow on nearby lands. The snow would pack into ice, and glaciers would start creeping south. Once the process was started, it might be impossible to stop before icecaps covered large parts of Europe and the U.S.

Another risky experiment with the oceans may have already been tried inadvertently. The temperature of the earth's surface depends to a considerable extent on the atmosphere's small content of carbon dioxide (about .03%), which permits short-wave sunlight to pass but impedes the escape of longer heat waves into space —the so-called '"greenhouse" effect. Since 1860 modern man's furnaces and auto exhausts have spewed out 360 billion tons of carbon dioxide. Warns Revelle: "By 2005 we will have added to the atmosphere some 1,700 billion tons of carbon dioxide—about 70% of the amount now present in the atmosphere. We believe that most of this will be absorbed by the ocean, but this means that the carbon dioxide in the atmosphere, if nothing else happens, will increase about 20%."

Result could be that air temperature would increase by 1° to 2° Centigrade. "Southern California might dry up completely if the temperature rose in the way we think it might—making it an impossible place to live, rather than almost impossible the way it is now." The ocean will also grow warmer, and will be forced to release dissolved carbon dioxide to the atmosphere. This will increase the greenhouse effect. At some point in this chain reaction, the Antarctic icecap will melt, adding enough water to the ocean to drown nearly all of the earth's great cities.

No one can estimate for sure the ocean's ability to absorb CO2. But man's future may depend on it. Concludes Revelle: "Man is moving and shaking the great globe itself in spite of himself. We may be disastrously changing the climate."