The phrase that best describes the image is this B.thermohaline circulation.
What is thermohaline circulation?
Thermohaline circulation, also known as the global conveyor belt, is a large-scale system of ocean currents that circulates water throughout the world's oceans.
This circulation is driven by differences in water density due to temperature and salinity.
Thermohaline circulation regulates Earth's climate. It helps to moderate temperature extremes, transport nutrients that support marine life, and redistribute heat from the tropics to the poles. It also helps to keep the equator warm and the poles cool, preventing extreme temperature swings.