Why do some winds blow constantly, and some blow almost exclusively in gusts? What creates gusts? I know how wind is “made”, but how do gusts happen? If it’s the same thing, just on a smaller scale, wouldn’t it be like that all the time, and not depend on the direction of the wind?
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Air is a fluid and so it helps to visualize it like water. Go down to a stream or pour water down a slope in your garden. The water will pile up behind objects then release in a gush, or a “gust” of water as it overwhelms that object. Now replace the rocks, shrubs, branches etc with buildings, trees etc. there’s also eddies, vortices and other types of air and water flow that cause gusts. These change shape as the landscape changes with wind because trees sway cars move etc. that big delivery truck moving slowly down the street sure changes how air flows between buildings, like dropping a rock in a stream.
The easiest answer is that wind is like sound. Sound comes in waves due to the chaotic nature of the universe and so do winds.
What does hot air do? It rises.
So what about the air that moves in to take it’s place? That’s wind.
Wind is caused when an area of high pressure balances with a nearby area of lower pressure. Think of blowing up a balloon, then letting the air out!
If you look at a wind map of the whole world, you’ll see it’s a mix of a bunch of different swirls of different wind speeds. That’s true on all scales. You’ll have the huge swirl of a large low pressure system, the medium-scale swirl of a thunderstorm in it, and small-scale eddies made by the wind as it moves past trees, buildings, etc. along with the flow.
A gust of wind is just your experience of one of those local regions of higher wind passing you by. In general, faster flows tend to be more turbulent (“swirly”), so they’re more common when it’s already windy.