Water warmed at the equator by the Sun flows into the North Atlantic, where it is cooled and becomes more salty because of evaporation. This cold, salty water sinks to the seafloor and forms a huge undersea river. The deep water flows through the oceans, welling up where winds push away warm surface water. This transfer of salty water is balanced by fresh water evaporated from the Atlantic and carried to the Pacific by the atmosphere. There, it falls as rain, diluting the upwelling salty water with fresh water.
Topic: Earth Science
Keywords: Atmospheric circulation, Seawater--Density, Oceanography, Temperature, Climatology, Ocean circulation, Ocean-atmosphere interaction, Ocean bottom, Fresh water