“Water Cycle” by Atmospheric Infrared Sounder is licensed under CC BY 2.0

You might be wondering how water gets into the sky in the first place. Well, every day, all the time, water from the land and the oceans is evaporating—becoming air. When the sun shines on water or ice, and it warms up, then a lot of evaporation is happening. The next time it rains, notice the puddles on the ground. One day they’re there, and the next day they’re gone! Especially on sunny days, the water in a puddle can evaporate very quickly.

Plants and animals let water into the air, too. Put your hand close over your mouth and breathe out. Did you feel the moisture—a tiny bit of water—on your hand? Water comes out of your mouth with every breath. When you “see your breath” on a cold day, that is water, too. In fact, those breath clouds are a lot like the clouds that form high up in the sky.

Water that evaporates into the air eventually forms clouds, which can make rain and snow. You might have heard of this whole process before. When water falls from the sky, spends some time on the land or in oceans, and then goes back up into the sky, all that movement of water is called the water cycle.