Atmospheric Motion

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The horizontal movement of air is controlled by -
Pressure Gradient force- This is the main driving force of global winds. This creates a wind from high-pressure, surplus areas to low-pressure, deficit areas. The closer isobars are together, the stronger the wind is.
Coriolis force- This is the deflection of wind due to the Earth’s rotation. Deflecting right in the northern hemisphere and left in the southern, with an increasing effect towards the poles. It is not present in the equator.
Geostropic wind- In mid-latitudes, the Pressure Gradient and Coriolis force are balanced. Therefore, air moves parallel to the isobars rather than from regions of high pressure to low pressure.
Centripetal force- Air moving towards a low-pressure area in a defected path accelerates towards the centre of low pressure
Frictional forces- Frictional drag from the Earth's surface decreases wind speed and modifies it's direction, crossing isobars as it moves from high-pressure regions to low-pressure regions areas.

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