Water regulates climate, storing heat during the day and releasing it at night. Water in the ocean and atmosphere carry heat from the tropics to the poles. The process by which water moves around the earth, from the ocean, to the atmosphere, to the land and back to the ocean is called the water cycle.

This animation of sea surface temperature shows the transport of heat along the ocean’s surface.

credits: NASA/Goddard Space Flight Center Scientific Visualization Studio; this is a contribution of the Consortium for Estimating the Circulation and Climate of the Ocean (ECCO) funded by the National Oceanographic Partnership Program; the Blue Marble data is courtesy of Reto Stockli (NASA/GSFC)