The Earth's atmosphere rotates along with the Earth. At what altitude does the atmosphere cease to rotate along with the Earth? Is it the altitude at which Gravity has no effect? Forgive me if it is a dumb question. I don't know too much about science.
Upper atmospheric air is coupled by friction to lower atmospheric air. So it will on the average spin near the same rotational rate as lower atmospheric air. The friction coupling to lower atmospheric air is greater than to the higher and thinner air.
Gravity always has some effect, it just gets less as one is further from the gravitational source. Think tides of the oceans getting manipulated by the sun and also the moon, both which are a good distance away, but still have some (quite measurable) effect.
Since air has mass, there is some inertia, however the air at higher altitudes is coupled via friction to lower atmospheric air, so any inertial forces are effectively coupled to the daily rotation of the earth, not to some "stopped" movement.
So bottom line, the air rotates around the earth daily, and is coupled via friction and other properties to the air below it, which is coupled more strongly to the surface of the earth. Think of a bunch of people walking around a round swimming pool, with the water spinning with them