National Geographic : 1953 Apr
504 The National Geographic Magazine and me to leave. We went reluctantly, re- placed by an augmented crew with still more equipment for probing sea, ice, and sky. As this is written, Fletcher 's Ice Island is still inhabited , and valuable work goes on. Ways in which temperatures of ice and at- mosphere affect each other are being studied. Gauges set between salt-water ice and island measure the terrific pressure of the pack. Weather information is most important, and broadcasts continue every six hours. Instruments now go far aloft on balloons. Equipment used to track their course was successfully flown in. C lues to Mysterious J et Stream In Washington , D. C., Air Weather Service meteorologists search reports from Fletcher 's Island for clues to the general circulation of the earth's atmosphere. Such information may help to explain the existence of the jet stream, the mysterious , undulating current of air that travels at high speed far above the earth. Knowledge of jet-stream positions often enables airmen to ride tail winds, cut- ting hours from long trips. Generally our island home proved itself directionally stable. It had no recognizable bow or stern, of course , but its inhabitants aligned it with true north by means of mark- ers arbitrarily established on the ice. Twice, for unknown reasons, the island made partial rotations in a clockwise direction, turn- ing the first time through 50 ° and the second through 80 ° . These rotations were slow, the 80 ° turn requiring nearly a month. A sensitive bubble level , reading to within 1/ 10 of a second of arc, showed that the island tilted a small, varying amount. This was as- cribed primarily to wind , but sometimes the levels were thrown into confusion by localized surface upheavals caused apparently by in- ternal pressures. Also products of pressures from within the island mass were strange " ice bumps. " These domelike protuberances occurred on the tops of ridges near the shores and were occasion- ally three feet high. Coring bits were driven down 52 feet. Within this distance 54 distinct layers of dirt were encountered. Mostly mineral matter, they also contained a few bits of twigs and leaves. The presence of the dirt was accounted for in several ways. Boulders and large earth mounds were terminal moraines left by tongues of glaciers which thrust out on the Ellesmere- fast shelf, then retreated. Summer streams coursing down from the land left silt and small pebbles. Some fine layers may have arrived as atmospheric dust. The boulders were conspicuous features of the landscape. Some were big, weighing many tons and measuring as much as 10 feet in diameter. They stood ranged in a rough row, as if a careless giant had tried to build a stone wall. A few of the smaller ones were shipped to the United States for study. A reliable estimate of the island 's thickness was made. Charges of TNT sent shock waves , which travel at known speeds , through the ice. Measuring the elapsed time, Crary and Cotell reported that our camp rested on a 150- foot-thick block of ice, a cold , inert mass as thick as a 14-story building is tall. The figure indicated that the original 200-foot estimate for T-1 might have been a bit high. To measure movements of the pack with relation to the ice island , our scientists triangu- lated on several big sea-ice hummocks. One day the most conspicuous of these toppled over with a roar. A persistent " warm " layer of ocean was discovered 400 feet below the sea's surface. Less than 150 feet thick , it averaged about 2 o warmer than the water above and below it. There was no sat isfactory explanation for its presence. Survey parties mapped the island in detail. Early in April the camp began taking its fresh water from two lakes found beneath four to eight feet of ice. Freezing on all sides subjected these water pockets to pressure; when first tapped they spouted in gushers. Passing sea birds were identified tentatively as gulls and jaegers. Nobody had time for hunting , nor for hiking two miles over the pack to the nearest open water where it might be possible for la rge marine animals , such as seals and narwhals, to come up for air. Winter darkness made it necessary to light the landing field , now provided with two run- ways. A complete portable lighting system was delivered by parachute. Men T oi l Through Long P ol ar Night An oceanographer, a marine biologist, and two geophysicists are among the nine men who have toiled ceaselessly through the Arc- tic's long winter night, adding constantly to our knowledge of one of the least understood regions on earth. Each day has brought a new discovery, a surprise, or a revision of previous theory. The future of the drifting polar base is difficult to predict. It could float off into warmer climes and break up , rejoin Target X back at its birthplace, or make another cir- cuit of the Arctic basin- possibly many more. Latest reports indicate that the ice island is beginning a second polar swing- good news for the Air Force , since it would mean an- other five or six years of useful service for T-3. If it does go around again, many of its former residents would like to go along.