thermohaline circulation

An ocean circulation at a planetary scale, responsible for renewing surface waters with intermediate and deep waters, of greater density than the former. Its name refers to temperature (prefix "thermo-") and to salt content (suffix "-haline," referring to the Latin term hals = salt). The THC (the acronym used in physical oceanography to abbreviate thermohaline circulation) is set in motion in areas of the sea surface where the water is denser than in adjacent areas, either because it is colder and/or also because it has higher salinity. Phenomena such as wind or tides can also contribute to this "ignition." The sinking of that water gradually gives rise to the slow renewal process, lasting several centuries. This heat transport mechanism - also known as the ocean conveyor belt -, complementary to that taking place in the atmosphere through the GAC, has a decisive influence on the Earth's climate.