Drifting Stations

From the beginnings of exploration and shipping within Arctic sea ice, the main problems encountered were related to poor knowledge of the ice and ocean's natural conditions. The use of Arctic sea routes, and exploration and development of the region's natural resources were impossible without understanding the typical spatial and temporal (seasonal and annual) variations in the atmosphere, ice cover, and oceanic water column. Thus, it was necessary to organize systematic observations of weather, ice, and water over the entire Arctic territory. In 1882-1883, under the framework of the First International Polar Year, specialists from 12 countries carried out wide-ranging scientific observations in the Arctic (including hydrometeorological observations), and new observation stations were opened. In subsequent years, the network of hydrometeorological stations significantly expanded; however, all were situated on the coast or on islands. Central areas of the Arctic Ocean remained a "blind spot" on weather and ice charts.

Extensive meteorological and oceanographic observations in the Arctic Basin were undertaken by Fridtjof Nansen on the voyage and drift of the Norwegian Polar Expedition ship Fram from 1893 to 1896. In

1938—1940, the Russian icebreaker Georgy Sedov repeated Fram's transarctic drift along a trajectory passing much further north. Systematic observations during the drift added much new information on ice and climate conditions in the central Arctic Basin.

Nansen was one of the first polar investigators to have the idea of making observations on drifting ice in the Arctic Ocean. However, these ideas were only put into practice in 1937 by the Soviet Union's Glavsevmorput (Chief Office for the Northern Sea Route). On May 21, 1937, an airplane piloted by Glavsevmorput's Mikhael Vodop'yanov made the first landing near the North Pole on an ice-floe at 89°43' N, and the first scientific drifting station North Pole-1 was set up in three tents with a radio mast. During its 1200 mile southward drift that ended on February 19, 1938 with relief from an icebreaker off the Greenland coast, Ivan Papanin, Piotr Shirshov, Yevgeny Fedorov, and Ernst Krenkel carried out a wide range of meteorological, hydrological, hydrobiological, astronomical, and geophysical studies.

A second Russian drifting station, North Pole-2, operated from 1950 to 1951. From April 15, 1954 to July 25,1991, manned drifting stations NP-3 to NP-31 made continuous observations. In some years, measurements were made simultaneously at three stations drifting in different areas of the Arctic Basin.

The history of US drifting stations began with the T-3 station, set up on an ice island in March 1952 by Joseph O. Fletcher of the US Air Force Weather Service. T-3 (also known as Fletcher's Ice Island) operated until May 1954. From then on it worked intermittently till 1973, and the Ice Island served as a platform for different studies and weather observations and a base for organizing other drifting stations. During the International Geophysical Year (IGY) (1957—1958), the T-3 station was called Ice Station Bravo. From April 1957 to November 1958, IGY observations were also carried out at Ice Station Alpha and from April

1959 to January 1960 at Ice Station Charlie. During a grounded phase of T-3, the US Navy planned a new drifting station, the Arctic Research Laboratory Ice Station I (ARLIS I), which operated from September

1960 to March 1961. ARLIS 1 was followed by ARLIS II, which drifted for much longer, from May 1961 to May 1965. In 1975—1976, under the framework of the Arctic Ice Dynamics Joint Experiment (AIDJEX), the United States, Canada, and Japan carried out observations at four camps set up on the drifting ice.

To establish a station on drifting ice, a sufficiently large, thick pack ice-floe had to be selected, making it possible to construct a runway for aircraft. The NP-19, 22, 23, 24, and ARLIS II stations were set up on ice islands calved from ice shelves. The organization of drifting stations, maintaining their life support, and rotation or evacuation of personnel was typically supported by aviation. Sometimes personnel and cargo were delivered by icebreakers and icebreaking vessels (NP-10, 22, 24, 29—31, and ARLIS I).

Ice drift occurs under the action of wind and sea currents. The character of ice drift in the Arctic Ocean is determined by the main pressure centers—the Arctic High and the Aleutian and Icelandic Lows. They generate two main drift systems: the Transpolar Drift and a circular anticyclonic drift (Beaufort Gyre) in the Canadian-American sector of the Arctic (the drift of the NP-2, 22, 31 and T-3 stations). T-3 made three circuits in the Beaufort Gyre before exiting the Arctic through Fram Strait via the Transpolar Drift. The drift trajectories constantly deviate due to changing winds. In the Arctic Basin, the true length of the drifting ice pathway is on average three times as great as the direct distance passed in a straight line. The average drift velocity of all NP stations over the observation period May 21, 1937 to July 25, 1991 (29,726 days) was 5.71 km a day. The total distance traveled by these stations equals 169,654 km (105,418 mi).

Each of the NP drifting stations allowed a branch of the Soviet All-Union Arctic Institute to conduct comprehensive studies of the environment and the processes occurring in it from the seabed to heights of a hundred kilometers in the ionosphere. Standard observations were typically conducted in oceanography, meteorology, solar radiation, upper-air sounding, geomagnetism, and geophysics (ionospheric processes). In addition to standard observations, the observation programs frequently included different types of specialized observations. These were measurements of the ice cover strength, seismic-acoustic characteristics of ice and the water column, hydrooptic characteristics, and aerosol and trace gases in the atmosphere. Data from standard meteorological observations were transmitted via radiochannels to all interested users, and primarily used to issue hydrometeorological forecasts and provide operational information for voyages along the Northern Sea Route and aviation flights at high latitudes.

In total, 88 teams of polar explorers worked at 31 NP stations on a rotation basis and 2009 people participated in the year-round cycles of studies. In addition, 8885 specialists carried out short-term studies of less than a year under special programs or occasionally visited the stations. The main achievement of the people who carried out regular observations under the severe conditions is that hundreds of researchers in different countries can now use these data for the modeling of Arctic meteorology and climate, and model oceanic pollutant transport at high latitudes. An enormous amount of data was generated in thousands of scientific articles, monographs, atlases, handbooks, and manuals. Until recently, the bulk of the Soviet publications were stored in national archives inaccessible to investigators from other countries. In 1995, the Environmental Working Group (EWG) was established under the framework of the US-Russian Joint Commission on Economic and Technological Cooperation. EWG decided to develop a set of three complementary climatic atlases—oceanography, sea ice, and meteorology—following the availability of previously restricted US and Russian data. In 1997-1998, the Oceanographic Atlas of the Arctic Ocean was released to the public on two CD-ROMs: one covering the winter period and the other the summer. In 2000, work on preparation of the Arctic Meteorology and Climate Atlas was completed.

Manned drifting stations may now have been superseded by automated drifting buoys operated by the International Arctic Buoy Program (see Meteorological Stations), although the Surface Heat Budget of the Arctic Ocean (SHEBA) operated a scientific research station from an icebreaker frozen into Arctic Ocean pack ice from October 1997 to October 1998 (see Oceanography: Research Programmes).

See also Ice Islands; Meteorological Stations; North Pole Air Expedition, 1937; Papanin, Ivan; Transpolar Drift

Vladimir Radionov

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