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Why does the ocean get colder at depth?

28 July 2010, 1:46 pm

Cold water has a higher density than warm water. Deep water gets colder at depth because cold, salty ocean water sinks to the bottom of the ocean basins. Less dense, warmer water rises to the surface. This process of rising and sinking water creates a complex pattern of ocean circulation called the 'global conveyor belt.'

Original article: Why does the ocean get colder at depth?