What happens to atmospheric pressure as you get higher up into the atmosphere? Why?

Question

What happens to atmospheric pressure as you get higher up into the atmosphere? Why?

Answer 1

At sea level, pressure is equal to 1 atm. As elevation increases, pressure decreases because air gets thinner. After all, pressure is the ratio of force and area. Less air means less area, and of course lower pressure.

Answer 2

Pressure lessens. At sea level, atmospheric pressure is something like 14.7 lbs per square inch. That means, at sea level, the weight of the air above it, for that square inch, is 14.7 lbs. The higher you go, the less air that is on top of that square inch. Therefore, less pressure.