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 and after two false starts, Nansen and Johansen began their journey on 14 March 1895. Nansen allowed 50 days to cover the to the pole, an average daily journey of . After a week of travel, a sextant observation indicated they averaged per day, which put them ahead of schedule. However, uneven surfaces made skiing more difficult, and their speeds slowed. They also realised they were marching against a southerly drift, and that distances travelled did not necessarily equate to distance progressed. On 3 April, Nansen began to doubt whether the pole was attainable. Unless their speed improved, their food