What is the thermohaline conveyor belt?
A process known as thermohaline circulation, or the ocean conveyor belt, drives these deep underwater currents. Thermohaline Circulation. Thermohaline circulation moves a massive current of water around the globe, from northern oceans to southern oceans, and back again.
The ocean circulation conveyor belt helps balance climate. As part of the ocean conveyor belt, warm water from the tropical Atlantic moves poleward near the surface where it gives up some of its heat to the atmosphere. This process partially moderates the cold temperatures at higher latitudes.
- The conveyor belt transfers warm water from the Pacific Ocean to the Atlantic as a shallow current and returns cold water from the Atlantic to the Pacific as a deep current that flows further south. As it passes Europe, the surface water evaporates and the ocean water cools, releasing heat to the atmosphere.
- Upwelling is a process in which deep, cold water rises toward the surface. This graphic shows how displaced surface waters are replaced by cold, nutrient-rich water that “wells up” from below. Winds blowing across the ocean surface push water away.
- There are a few types of ocean waves and they are generally classified by the energy source that creates them. Most common are surface waves, caused by wind blowing along the air-water interface, creating a disturbance that steadily builds as wind continues to blow and the wave crest rises.
The blue arrows indicate the path of deep, cold, dense water currents. The red arrows indicate the path of warmer, less dense surface waters. It is estimated that it can take 1,000 years for a "parcel" of water to complete the journey along the global conveyor belt.
- Simply put, ice triggers the movement of ocean currents. As water freezes in the North and South Poles, the water surrounding the ice becomes saltier and colder, since the salt leaves the water upon freezing. The ice then cools the water surrounding it. The cold, salty water then sinks due to its increased density.
- The Hawaiian Islands were formed by volcanic activity. In areas where the plates come together, sometimes volcanoes will form. Volcanoes can also form in the middle of a plate, where magma rises upward until it erupts on the seafloor, at what is called a “hot spot.”
- Winds drive ocean currents in the upper 100 meters of the ocean's surface. These deep-ocean currents are driven by differences in the water's density, which is controlled by temperature (thermo) and salinity (haline). This process is known as thermohaline circulation.
Updated: 4th December 2019