The Atlantic meridional overturning circulation (AMOC) is the main ocean current system in the Atlantic Ocean. It is a major component of Earth's ocean circulation system and plays an important role in the planet's climate system. The AMOC includes Atlantic currents at the surface and at great depths that are driven by changes in weather, temperature and salinity. Those currents comprise half of the global thermohaline circulation that includes the flow of major ocean currents, the other half being the Southern Ocean overturning circulation.