The term conveyor belt has been adopted to express the idea of the ocean-based elements of the climate system which transport heat. The global conveyor belt (known technically as the thermohaline circulation) operates when the heat from the sun on the Atlantic Ocean is conveyed northward by currents, heating the north Atlantic. The ocean loses its heat in the very northern reaches and can become more saline due to ice production. The cold water sinks to the bottom (forming North Atlantic Deep Water) and circulates to complete the conveyor belt.

See also: downwelling, upwelling, thermohaline circulation