Final answer:
Global air circulation is driven by convection and is influenced by Earth's rotation. The circulation of air in the atmosphere can be divided into three cells: Hadley cell, Ferrel cell, and Polar cell. Each cell is driven by different factors such as solar heating, interaction between cells, and the flow of cold air.
Step-by-step explanation:
Global air circulation is driven by convection, which is the large-scale flow of matter. On Earth, the atmospheric circulation is caused by the flow of hot air from the tropics to the poles, and the flow of cold air from the poles toward the tropics. This circulation is influenced by Earth's rotation, known as the Coriolis effect. The circulation of air in the atmosphere can be divided into three main cells: Hadley cell, Ferrel cell, and Polar cell. The Hadley cell is driven by the intense solar heating at the equator. As air near the equator heats up, it rises and flows towards the poles. This creates low pressure at the equator. The rising air then cools and sinks at around 30 degrees latitude, creating high pressure. The Ferrel cell is driven by the interaction between the Hadley and Polar cells. At the boundary between the two cells, air from the Polar cell sinks and creates a region of high pressure. This sinking air displaces air from the Ferrel cell, which rises to create a region of low pressure. The Polar cell is driven by the flow of cold air from the poles towards the lower latitudes. This cold air sinks at the poles, creating high pressure.