What causes wind formation?

the constant density of air

the movement of Earth on its axis

the temperature differences in the hemispheres

the turning of circulating air currents

The temperature differences in the hemispheres and the turning of circulating air currents are the main factors that cause wind formation. Air moves because of differences in temperature between two areas. When the air in one location is warmer than the air in another location, it creates a difference in air pressure. This pressure difference causes air to move from the high-pressure area to the low-pressure area, creating wind. Additionally, the rotation of Earth on its axis and the Coriolis effect cause circulating air currents to turn, leading to the formation of different wind patterns.

so which one

Both the temperature differences in the hemispheres and the turning of circulating air currents are causes of wind formation. They work together in a complex system to create the wind patterns we observe.