47. Surface water in the N. Atlantic near Greenland sinks, displacing deeper water and drawing warm tropical surface water pole-ward creating the .

thermohaline circulation

Explanation:

Thermohaline circulation occurs through the difference in density between the waters of the sea current in relation to the temperature and the amount of salt that they present. Thus, this oceanographic phenomenon makes the waters with the highest concentrations of salt, the surface waters in the North Atlantic, near Greenland, are swallowed by the part with the lowest concentration, sinking completely and causing a turnaround in the maritime space. This throws the waters with the lowest salt concentration upwards, displacing the deeper waters and attracting the warm tropical surface waters