What is the pressure gradient force?

The pressure gradient force is a fundamental concept in meteorology that describes how differences in atmospheric pressure create forces that affect wind movement. This force arises from the spatial variation in atmospheric pressure, acting to equalize these differences.

When there is a difference in pressure over distance, the pressure gradient force points from high pressure to low pressure, and it acts perpendicular to the isobars, which are lines of equal pressure on a weather map. This force is what initiates wind; the greater the pressure difference over a certain distance, the stronger the wind that is generated.

Understanding this force is essential because it helps explain how winds develop, which is crucial for weather forecasting and understanding weather patterns. The other options presented either describe unrelated meteorological phenomena or inaccuracies regarding the nature of the pressure gradient force.