Video courtesy of the Little Shop of Physics.
Wind Speed and Direction at Different Heights
We know that all areas of the globe have prevailing winds, but the wind direction is affected by local topography, as we can see in this segment. On a tabletop, obstructions can change - or even reverse - the direction of the wind, and the same principle is at work at larger scales. In the world around us, this may mean that the wind is blowing in different directions at different heights. If the change in direction takes place over a short distance, this is known as wind shear. If you look at the motion of clouds on most days, you'll see that clouds at different elevations move in different directions. In this segment, you can see exactly this effect - speeded up for better viewing - as well as some more prosaic tests of wind speed variation with height using balloons and model rocket plumes.
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