Geophysical and oceanographical exploration of the Arctic Ocean has progressed largely with the aid of drifting research stations established on pack ice. The earliest drift expedition was carried out between 1893 and 1896 by the Norwegian scientist and explorer, Fridtjof Nansen, who allowed his especially constructed vessel, Fram, to freeze into the ice to be carried by winds and currents. During this time Nansen and his men conducted a remarkable and wide-ranging program of scientific studies.

Over the past three decades, a number of manned scientific research stations have been established by the United States on arctic sea ice in the Amerasia Basin of the Arctic Ocean. These stations were supported by aircraft which w e r e based at the Naval Arctic Research Laboratory in Barrow, Alaska. Increasingly, however, scientific interest has grown in the Eurasia Basin of the Arctic Ocean, which is not readily accessible by air from Alaska. The Eurasia Basin contains the Arctic Midoceanic Ridge, which extends in a straight line for 2000 km between the Greenland-Spits bergen Passage and the Laptev Shelf. The Eurasia Basin is also the region within w h i c h the waters of the Atlantic Ocean mix with those of the Arctic. A number of geophysical, oceanographic, and climatic questions center around these two features of the Eurasia Basin.