What Causes Wind?

What causes wind?

This question comes up when working on the Weather Merit Badge. And no, the answer is not chili!

The earth is round, and has mountains and valleys. Land and bodies of water. Which means that when the sun rises and starts to warm up the earth, it does so unevenly. Also, this third rock from the sun is constantly rotating and tilting causing seasons to change.

As the sun shines down onto the earth. It warms up the area. And what does hot air do? That’s right, it rises. This is also known as a low pressure. The pockets of cooler air start moving to fill the pockets caused by the warmer air rising. The pockets of the cooler air is known as a high pressure. When watching the morning or evening news for the weather report, you will hear the meteorologist use these terms of “low” and “high” pressure. The force pushing the air horizontally between the high and low pressure is known as “pressure gradient force.” The short answer to the above question is hot and cold air mixing and moving together.

Here is one of the best science experiments I have seen on the subject.