Because gravity pulls down on all levels in the atmosphere, the pressure increases all the way to the ground.
This is a good example of an exponential change. This happens often where something is affected by what has gone before. Examples:
– Population growth (for cells, each dividing in two doubles the population)
– Rockets to space (propellant usage makes rockets continuously lighter)
– Inflating tires (increasing pressure makes pumping harder)
The next page provides additional technical information…