|A schematic of modern thermohaline circulation. Tens of millions of years ago, continental plate motility formed a land-free gap to a greater extent than or less Antarctica, allowing formation of the ACC which keeps warm waters away from Antarctica.|
Thermohaline circulation (THC) is a business office of the large-scale sea circulation that is driven past times global density gradients created past times surface rut together with freshwater fluxes. The describing word thermohaline derives from thermo- referring to temperature together with -haline referring to common salt content, factors which together hit upward one’s require heed the density of sea water. Wind-driven surface currents (such every bit the Gulf Stream) move polewards from the equatorial Atlantic Ocean, cooling en route, together with eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense H2O so flows into the sea basins. While the mass of it upwells inward the Southern Ocean, the oldest waters (with a transit fourth dimension of to a greater extent than or less chiliad years) upwell inward the North Pacific. Extensive mixing hence takes house betwixt the sea basins, reducing differences betwixt them together with making the Earth’s oceans a global system. On their journey, the H2O masses carry both unloosen energy (in the cast of heat) together with affair (solids, dissolved substances together with gases) to a greater extent than or less the globe. As such, the nation of the circulation has a large touching on on the climate of the Earth.
The thermohaline circulation is sometimes called the sea conveyor belt, the groovy sea conveyor, or the global conveyor belt. On occasion, it is used to holler to the meridional overturning circulation (often abbreviated every bit MOC). The term MOC, however, is to a greater extent than accurate together with good defined, every bit it is hard to split the business office of the circulation which is genuinely driven past times temperature together with salinity lonely every bit opposed to other factors such every bit the air current together with tidal forces.
|A summary of the path of the thermohaline circulation. Blue paths correspond deep-water currents, patch carmine paths correspond surface currents.|