Question

A planetary wind caused by convection cells over the earth

Answer 1

These vast movements are called planetary winds, and they are driven by the circulation of air in atmospheric units called cells. The heat of the Sun causes winds around the world. It heats the tropical zone more than the polar regions because its rays are more direct at the equator.

Answer 2

Warm air rises , creating a low pressure region , and cool air  sinks , creating a high pressure zone . Air flowing from areas of high pressure to low pressure creates winds . Air moving at the bases of three major convection cells in each hemisphere north and south of the eqautor creates the global wind belts .