The air lowers its pressure with altitude, and fog appears.
It lowers its pressure above draws of water, as well (the ones that are usually considered draws in the land), creating streams and riparian zones.
Those points in the land manipulate the air. You could say they depressurize the Earth at the same time they depressurize the air. These are the systems of flight. This is what the flight of a hawk looks like.
What it flies over, sure, but the flight itself as well.