The horizontal movement of air form high pressure zone to low pressure zone is called wind. The pressure belts shift according to the apparent movement of the sun. The nature of wind is influenced by variations in pressure, rotation of earth and the features of the region over which it blows.
Pressure gradient:The change in pressure with horizontal distance is termed as pressure gradient. The pressure gradient is said to be steeper when the pressure difference is more. In such places, the speed of wind will also be more.
Coriolis force: French mathematician Coriolis observed that due to a force generated as a result of the earth’s rotation, freely moving bodies get deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is known as Coriolis force. Admiral Ferrel, an American scientist noted that as winds are free movement of air, they get deflected. Coriolis force formed as a result of earth’s rotation, deflects the winds.
Friction: Friction is something that prevents the free movement of wind. The speed of wind will be high over ocean surface and level lands as the friction is less. On the other hand friction is more along difficult terrains and places with dense forest cover. So the speed of wind will be less in those places.