The amount of force that air exerts on the Earth is called air pressure.

Here's why:

* Air has weight: Even though it's invisible, air is made up of molecules that have mass. This mass exerts a force on the surface below it.

* Gravity: Earth's gravity pulls the air molecules towards the surface, creating a force that presses down.

This force, or air pressure, is measured in units like pascals (Pa) or pounds per square inch (psi). It varies depending on altitude, temperature, and weather conditions.