You try placing a small balloon into a significantly bigger one, then, accelerate the bigger balloon upwards. What happens? The small balloon will hit the bottom of the bigger balloon.
The Earth is accelerating the air? haha.
I don't say this often, but you're a fucking moron.
The easiest example to make you understand is this:
Air is a fluid. Water, is also a fluid (granted much more dense). Now fill up a bath tub, place your hand in the water palm-up, and parallel to the bottom. Now, swiftly move your hand up towards the surface and notice what happens. This is equivalent to what the Earth does to the air.
So like he said, air resistance.