2. Great Ocean Conveyer

History 8 Agriculture Vocabulary

The Great Ocean Conveyor Belt, also known as the meridional overturning current (MOC) or the thermohaline circulation (THC), is "a constantly moving system of deep-ocean circulation driven by temperature and salinity" (3, 1). It is "a vital component of the global ocean nutrient and carbon dioxide cycles" (2). Cold, salty water is dense and sinks to the bottom of the ocean, while warm water is less dense and rises (just like cold and warm air). The Conveyor begins in the Norwegian Sea, where warm water from the Gulf Stream heats the atmosphere. This loss of heat to the atmosphere makes the water cooler and denser, causing it to sink to the bottom of the ocean. This cold bottom water flows south, all the way down to Antarctica. Eventually, these cold bottom waters returm to the surface through "mixing and wind-driven upwelling" (1).

(3)

Sources:

(1) http://oceanservice.noaa.gov/facts/conveyor.html

(2) Ancient Origins page 72

(3) http://theresilientearth.com/?q=content/conveyor-belt-model-broken

To find further reading, visit http://enviroliteracy.org/water/oceans/the-great-ocean-conveyer-belt/.