The seven elements of weather (temperature, pressure, wind, moisture, clouds, precipitation, and visibility) can all be boiled down to temperature, pressure, and moisture. A couple of weeks ago we looked at temperature, last week we looked at pressure, and next week we will look at moisture. Today we’re going to take a brief look at wind, which is related to pressure.
Wind is the motion of air, caused by a difference in pressure.
As I’ve said before, the earth and the atmosphere is always trying to balance out any inequalities. Note the figure above. The column of air on the left has more molecules (thus has a higher pressure) than the column on the right. Some of these molecules will “want” to move over to the right, to balance out the two columns.
This illustrates a key principle of the atmosphere: wind blows from high to low pressure. Furthermore, the stronger the pressure gradient (i.e., the greater the pressure difference), the stronger the wind (e.g., think of the low pressure inside of and strong pressure gradients in hurricanes).
Come back next Monday as we talk about moisture, the next element of weather.