Arctic Ocean deepest point is Litke Deep in the Eurasian Basin, at . The two major basins are further subdivided by ridges into the Canada Basin (between Alaska/Canada and the Alpha Ridge), Makarov Basin (between the Alpha and Lomonosov Ridges), Amundsen Basin (between Lomonosov and Gakkel ridges), and Nansen Basin (between the Gakkel Ridge and the continental shelf that includes the Franz Josef Land). In large parts of the Arctic Ocean, the top layer (about ) is of lower salinity and lower temperature than the rest. It remains relatively stable, because the salinity effect on density is bigger than the temperature effect.
Fridtjof Nansen carried out researches in the northern Atlantic, and in 1912 he took his own yacht, "Veslemøy", to Bear Island and Spitsbergen. The main objective of the "Veslemøy" cruise was the investigation of salinity in the North Polar Basin. One of Nansen's lasting contributions to oceanography was his work designing instruments and equipment; the "Nansen bottle" for taking deep water samples remained in use into the 21st century, in a version updated by Shale Niskin. At the request of the Royal Geographical Society, Nansen began work on a study of Arctic discoveries, which developed into a two-volume history of the exploration