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.
HNoMS Fridtjof Nansen (F310) with two ultra-fast RHIBs as a replacement. In November 2009 she became involved in a fire-fight with suspected pirates after being attacked while inspecting a fishing vessel. In 2014, "Fridtjof Nansen" took part in the naval exercise RIMPAC 2014 in the Pacific Ocean. During the exercise, she used a Naval Strike Missile to sink the , a decommissioned U.S. Navy amphibious transport dock, as a target 55 nautical miles northwest of Hawaii on 10 July 2014. HNoMS Fridtjof Nansen (F310) HNoMS "Fridtjof Nansen" is a frigate of the Royal Norwegian Navy. Launched on 5 April 2006, she is the lead