What is the name of the global belt of surface and density currents that distribute thermal energy around the Earth?

• A. Gulf Stream
• B. Thermohaline circulation
• C. Great Ocean Conveyor Belt
• D. Ekman transport

Answer: (C)

Heat is moved around Earth by a connected system of surface and deep currents—the Great Ocean Conveyor Belt. This describes how warm surface currents spread heat horizontally across basins, while water near the poles becomes dense enough to sink and drive deep, return flows. The loop continues as deep waters travel toward the equator, upwell, and eventually rise to the surface again to feed new surface currents. That global, intertwined pattern is why this name fits best for the whole belt.

The Gulf Stream is a major warm current within this system, contributing to the heat transport, and Ekman transport explains how wind creates surface currents, but neither alone captures the global, continuous loop. Thermohaline circulation refers to the density-driven part that powers the deep currents, which is essential to the belt, but the term that names the entire global circulation pattern is the Great Ocean Conveyor Belt.