Where does wind come from? I thought it came from clouds but I’ve just had two really windy days with no clouds in sight



Where does wind come from? I thought it came from clouds but I’ve just had two really windy days with no clouds in sight

In: Earth Science

Hot air goes up, usually heated by the sun.
Some cold air comes rushing in to get the place of the previous air, and wind is created.

Earth’s rotation and different heating on different spots also contributes to winds, but is basically hot air going up and could air coming to take its place.

It comes from higher pressure cells moving into lower pressure cells. Essentially when some portion of the atmosphere or air gains heat energy it becomes excited and tends to expand and move around which can displace some colder areas of the atmosphere…it exerts force and movement. Molecules are bumping into each other and swirling and flowing and pushing each other along. The warmer the air is the more space is going to take up and the colder the air is the less space is going to take up, so warm air has higher pressure and cold air has lower pressure. The heat tends to want to transfer to the cold so higher pressure cells are drawn to lower pressure cells and that can produce molecular/atmospheric movement that we feel as wind.

On the global scale winds is caused by the difference in solar heating and earth rotation.

Hot air expands and the density decrease. Colder is around can then come in from the sider and lift the warmer air up. This is why hot air balloons can fly and why hot air rises over candles etc.

Land and water heat up at different rates. The same is the case for different types of land like forest vs grassland. Th polar region gets less sunlight than the equator. So

This effect result directly in sea breeze where the land gets hotter than the water in the sun and you get a breeze from the water towards land. During the night the land can cool down fast and the water is not warmer so cooler air moves out from land to the sea.

Earth rotation can cause more wind when there is some moment in the air toward or away from the poles. The ground on the equator has to move faster than on the poles to rotate once per day. So move 1670 km/h (1000mph) but on the poles, the tangential speed is zero.

So the air that moves away from the equator moves slightly faster than the ground below it and wait that move towards the equator move slightly slower.
This is a major part of why hurricanes and other weather phenomena rotate. The rotation direction is always the same on the north side of the equator and the opposite south of it.

So it is not clouds but solar heating and earth rotation on a local and global scale.

The sun heats the earth unevenly for a bunch of different reasons. This creates relatively warmer and cooler areas. Increased heat creates areas of higher (and thus areas of lower) air pressure. If the pressure is higher in one area than another, the air will move, creating wind.