Why is air pressure greatest at the Earth's surface?

1 Answer
Aug 2, 2018

Answer:

At sea level, air pressure is greatest because it is caused by the weight of the entire column of atmosphere at that altitude.

Explanation:

Air pressure is caused by the weight of the atmosphere pressing down on a location. At sea level, air pressure is greatest because it is caused by the weight of the entire column of atmosphere at that altitude over that location. As altitude increases, the column of atmosphere gets shorter, and so less weight is pressing down at a given altitude, so atmospheric pressure is reduced.