Science: Ocean Frontier

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Swarm in Sunlight. With their mounting knowledge, oceanographers are talking with new confidence of the ocean as a source of food. Life began in the sea, and most of it lives there still, grazing on the microscopic plants that swarm in the sunlit upper waters. At the end of a long food-chain (diatoms, protozoa, tiny crustaceans, little fish, etc.) are the fish, lobsters, shrimps and whales that are hunted by humans. Says Iselin: "We are not harvesting the seas. We are just hunting—catching something here and there."

Oceanographers are helping the hunters by plotting the trails fish follow, which are mostly determined by shifting ocean currents and the consequent shift in water temperatures. But they are also thinking about the possibility of fertilizing the ocean. Some parts of it are naturally rich and boiling with life. The water of breaking waves in such areas is green and turbid because it is full of microscopic plants and animals grazing on them. But large parts of the ocean are deserts with hardly any life. Their breaking waves are sapphire blue, the color of clear and lifeless water. Fish migrate away like cattle from a grazed-out range.

In fertile parts of the sea, the surface water is kept supplied with nutrients by some sort of upwelling that brings rich bottom water to the surface. In far northern and far southern parts of the ocean,—the surface water gets so cold and heavy in winter that it sinks and is replaced by bottom water that contains plant nutrients. Currents carry these nutrients to other seas, e.g., the Labrador Current off the Newfoundland banks, the Peru Current off the coast of South America, and produce rich fishing grounds.

Unless they are fertilized by currents from colder areas, tropical seas are largely sterile. Since the richest harvests of the sea derive from bottom water rising to the surface, oceanographers have long had the notion of creating artificial upwelling in sterile parts of the ocean. One possibility is a nuclear reactor sitting on the bottom and slightly warming the water around it. The warmed water will rise, carrying nutrients to the surface and turning clear water, admired only by tourists, into rich, turbid pastures. Another way would be to pump deep water into some closed area, such as a Pacific atoll, to make a kind of concentrated fish farm.

Serpents in the Depths? Despite the new outburst of exploration, many mysteries remain. The creatures that live in the depths of the ocean are still only slightly known, and they may include the famed sea serpents of salty folklore. Sea-serpent sightings have diminished of late, but Revelle thinks this may be because fast, noisy, modern ships make poor platforms for serpent sighting. Sperm whales dive for gigantic squid up to 50 ft. long that live at great depths and have never been captured by man. Why should not the squid have companions down there?

Chief sea-serpent man is Biologist John D. Isaacs, who is working out ways to catch the inhabitants of the depths of the ocean. One under study is a disk several hundred feet in diameter, with floats around the edge and ballast in the center. When it reaches a predetermined depth, the ballast will be detached, and the floats will pull the net upward. As it rises, it will inflate with water just as a parachute inflates with air, scooping up any giant squid and sea serpents on the way.