Ecology: Menace in the Skies

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Other scientists are concerned about the tremendous quantities of carbon dioxide released into the air by the burning of "fossil fuels" like coal and oil. Because it is being produced faster than it can be absorbed by the ocean or converted back into carbon and oxygen by plants, some scientists think that the carbon dioxide in the atmosphere has increased by about 10% since the turn of the century. The gas produces a "greenhouse" effect in the atmosphere; it allows sunlight to penetrate it, but effectively blocks the heat generated on earth by the sun's rays from escaping back into space.

No Apocalypse. There has already been a noticeable effect on earth—a gradual warming trend. As the carbon-dioxide buildup continues and even accelerates, scientists fear that average temperatures may, in the course of decades, rise enough to melt the polar ice caps. Since this would raise ocean levels more than 100 feet, it would effectively drown the smog problems of the world's coastal cities.

The waters, however, need never rise. Within his grasp, man has the means to prevent any such apocalyptic end. Over the short run, fuels can be used that produce far less pollutant as they burn. Chimneys can be filtered so that particulate smoke is reduced. Automobile engines and anti-exhaust devices can be made far more efficient. What is needed is recognition of the danger by the individual citizen and his government, the establishment of sound standards, and the drafting of impartial rules to govern the producers of pollution. Over the long run, the development of such relatively nonpolluting power sources as nuclear energy and electric fuel cells can help guarantee mankind the right to breathe.