system
Given the following post, respond as if you're commenting on Reddit:
human
Why don’t clouds get blown apart?

How do clouds stay together in (mostly) the same shapes in high winds? Why doesn’t the wind just disperse the clouds like a cloud of smoke?
gpt
Wind itself wouldn't disperse smoke either, you need wind *shear*, which is a change in the wind's speed in the direction perpendicular to it, to disperse something. While us surface-dwellers encounter high wind shear almost any time there's wind due to the ground, trees, buildings, or just about anything else that gets in the way, high up in the atmosphere it's less extreme. From the perspective of a cloud being carried by winds with little to no wind shear, it might as well be staying still while everything else moves around it. Think of flying, headwinds and tailwinds high in the atmosphere can move very fast and make a big difference in flight times, but planes aren't constantly battered about by the high winds because all of the air is moving at basically the same speed. When there are sudden changes in wind speed the plane experiences turbulence.