The Sun, jars and wind

Wind is air that moves. It begins with heating. The Sun warms the ground, and the ground warms the air above it. Warm air rises. Cooler air from the sides flows in to take its place. The moving air is wind. Wherever the ground is warmed more than its surroundings, wind can form. On the whole Earth, the same idea makes big patterns: air rises near the equator, flows toward cooler regions and sinks again, and the Earth’s rotation bends these winds. The result is the global winds. So wind is another example of convection, driven by the Sun’s energy. Wind also carries water vapour and clouds from one place to another, so it is part of the water cycle too.