字幕列表 影片播放 列印英文字幕 Ahh! When you're thirsty, nothing is better than a nice cool drink of water! Oh, and it looks like my plant could use a drink, too! Did you ever stop to think about where our water comes from? Sure, when you get a drink of water, it might come from a faucet or a bottle…and I give my flower here water from a watering can... But you know what? The water that comes out of the faucet and the watering can may once have been part of a cloud...or a snowflake...or even the ocean! Awesome, right? ...and it's because of something called the water cycle. Now, a cycle is a set of steps that repeat over and over. When you get to the last step in a cycle, you go back to the beginning and go through the steps again. For example, every year there are four seasons...spring, summer, fall and winter. And when when winter's over...it's time for spring again! We go back to the beginning of the cycle. In the water cycle, all of the water on Earth goes through a set of steps that repeat over and over. Let's start with the step in the water cycle where we open up our umbrellas… ...that's right, Squeaks! Rain. Rain is water that falls from the sky. Some rainwater soaks into the ground. But a lot of it flows into little creeks and streams, and then ends up in rivers, lakes...and eventually … the ocean! And then something really interesting happens. Some of this water changes. You might have noticed that after it rains, some water is left on the ground, like in puddles you can jump in. But what happens to all that water? It seems like it's there one day, but then, after a little while ...it's gone! Well, that water didn't just disappear. When the sun comes out and the ground gets warm, water can change into a different form. We call this form water vapor...and water vapor is a gas. The air we breathe, it's a bunch of different gases mixed together! And like the gases that make up air, you can't see water vapor gas. When the sun shines on rivers, lakes, and oceans, some of the water changes into water vapor. And then the water vapor goes up high...very high...up into the sky. And it gets pretty cold up there! So, when the water vapor gets high enough, it starts to get cool. And as water vapor cools down ... it changes back into little drops of liquid water. You can actually see water vapor change into water drops right at home! All you need is a mirror or window...and your mouth! Put your face close to the mirror or window, open your mouth nice and wide...and breathe out. What happens? The glass gets foggy. That's because there's water vapor in your warm breath. And when the water vapor in your breath touches the cool glass, it changes into teeny tiny droplets. A lot of the droplets together make the glass look cloudy. And up in the sky, a lot of water droplets together make … clouds! When there's a lot of water in a cloud, the cloud starts to get darker. White fluffy clouds start to turn gray. And as the clouds get grayer, the water in them gets heavier. When the water gets too heavy, it falls...right back out of the clouds, as rain. And rain is where we started in the cycle! We made it all the way back to the beginning! Now the water cycle can start over again. All the water on our great big Earth goes through this same cycle, over and over. Its falls the ground as rain or snow. And soon that water ends up in a river, lake, or ocean. From there, it heats up and turns into vapor. And when the vapor rises into the sky and cools off, it comes right back down! So the water that you drink, and the water that's in my watering can right now, might once have been part of a raindrop that fell into the ocean on the other side of the world! Think about that next time you take a drink! Thanks for joining me on SciShow Kids! Do you have a question about the weather...or anything else? Ask a grownup to help you leave a comment below, or send us an email to firstname.lastname@example.org. we'll see you next time, here at the fort!