ThoughtCo. – An important characteristic of the Earth’s atmosphere is its air pressure, which determines wind and weather patterns across the globe. By definition, atmospheric or air pressure is the force per unit of area exerted on the Earth’s surface by the weight of the air above the surface.
The number of air molecules above a surface determines air pressure. As the number of molecules increases or decreases, they exert more or less pressure on a surface, and the total atmospheric pressure increases or decreases.
By studying these highs and lows, scientists are better able to understand the Earth’s circulation patterns and predict the weather for use in daily life, navigation, shipping, and other important activities, making air pressure an important component to meteorology and other atmospheric science.
