SCIENTISTS’ REPORTS. THIRD LESS IN 50 YEARS.
(By THOMAS R. HENRY.) WASHINGTON.
The ice of the Arctic Ocean is melting so rapidly that more than one-third of it has disappeared in fifty years.
This is the conclusion that may be drawn from the remarkable drift of the Russian ice-breaker Sedov last winter, first detailed reports of which have just been received in the United States.
In the autumn of 1939 the Sedov was caught in the ice of the Laptev Sea between the northern coast of Siberia and the new Siberian Islands. She began to drift northwards and westward and on January 1, 1940. In broke out on the edge of the Greenland Sea between the northernmost point of Spitsbergen and Greenland.
Then she returned to Murmansk with complete reports of the remarkable experience which were placed in the hands of the Russian meteorologist N N. Zubov, for detailed analysis.
The significance of the records of this involuntary voyage comes from comparison with those taken by the Norwegian explorer, Fridtjof Nansen, in 1893. His specially constructed ship, the Fram, followed a roughly similiar course. Nansen recorded a maximum ice thickness of 365 centimetres. In similar positions the captain of the Sedov found the greatest thickness was 218 centimetres. The lowest temperature he recorded was 41 degrees below zero. Nansen ran into a minimum of 52 below. Nansen’s ship drifted for nearly two years over a course that was covered by the Sedov in about six months.
The Sedov records are also better than the less reliable ones taken during the winter of 1937-38 by the Russian North Pole flyer Papenin and his companions, who drifted on an ice floe and are very similar to those of the Russian icebreaker Lenin, which was caught in the same Laptev Sea a little earlier than the Sedov, but soon made its escape.
The higher winter temperatures, American experts say, might be considered a temporary fluctuation, but the ice thickness measurements show clearly that the trend to warmer weather in the Arctic basin must have, been continuous for some years.
The Sedov evidence, it is pointed out in a report of the voyage in the current journal of the American Geographical Society, confirms indications from several other sources which have been accumulating during the past few years, including the reports of the United States coastguard ice patrol in the North Atlantic.
Even allowing for gross inaccuracies in the Russian measurements, the geographic journal explains that the speed of the Sedov compared with that of the Fram, which can be verified beyond question, shows that the Arctic is getting much warmer.
It means that the ice is moving much faster from the Arctic basin into the Greenland Sea. This could he accounted for by an increase in the flow of warm Atlantic waters into the Polar basin, which in turn would bring about a reduction in the volume of ice in the seas bordering the Arctic, a decrease, in the volume of Polar ice and the size of glaciers, and a rise in the winter temperature of the air.
The analysis of the Sedov results, it is explained, confirms some of the laws of Arctic circulation first laid down bv Nansen and makes possible the statement of several other laws. Dr. Zubov confirmed especially that drift of ice is in the direction of the prevalent winds. The gradual melting of the Arctic has not yet been confirmed by sea-level measurements on the Atlantic and Pacific coast lines.
Great Climatic Fluctuations.
There have been speculations that if this should take place suddenly it would result in flooding some of the big Atlantic coast line cities of North America.
There is also speculation as to whether the course followed by the Sedov is a fair sample. It is known from geological and historical evidence that the Arctic climate is subject to great fluctuations.
Great coal deposits in Greenland and Spitsbergen indicate that the climate was once semi-tropical. It is also known that a prosperous Norse colony was established in Southern Greenland, but after about 300 years was starved out, probably bv a climatic change.
The reports of the captain of the Sedov are supported, it is said, by the report just issued of a University of Cambridge expedition in the winter of 1938 to Jan Maycn Island, off the eastern coast of Greenland. This is a Norse possession. It is extremely desolate, and in the past it has been used only as a sentry post of the Arctic through a weather observing station maintained there by the Norwegian Government. This has now stopped operations.
Study of the scanty flora of the island, compared with the collections made by previous expeditions, convinced the Cambridge explorers that Jan Mayeni was having definitely better winter temperatures. They were the first to climb the island’s chief volcano, 7680ft high, which they named in honour of the now exiled King Haakon as a tribute to his sovereignty over the desolate spot.
The Sedov traversed a little known region and found a great impassable no man’s area of hummocky ice extending for many miles between the northern shores of Franz Josef Land and the North Pole. It separates the younger ice formed mainly on the continental shelf from the thicker ice near the Pole. | (N.A.N.A.)