Hi, Squeaks.
Oh, you look like you're deep in thought.
What are you thinking about?
Oh, that's cool.
Squeaks says he's trying to figure out how the water faucet in the fort's kitchen works.
He has a hypothesis or idea about where the water comes from when you turn on the faucet.
Nice.
What's your hypothesis?
Squeaks thinks maybe there's a tiny person in there taking a nice bath and sharing their bath water with us.
I'm afraid that's not it though.
A little dragon who's crying?
That would be funny, but I don't think so.
See, the water in the faucet doesn't come from inside it.
It comes from somewhere else.
Well, some people's drinking water comes from underground.
It's true!
When we water our garden from the well in the backyard, we're using groundwater water that comes from rain and snow, that soak into the ground and is stored inside the earth.
In North America, where we live, a lot of people's running water also comes from rivers.
Here, check this out, Squeaks.
We're here in North America.
If you live over here in Minneapolis or St.
Paul, you get water from the Mississippi River.
That's this big, long river here.
There are rivers all over the world, like this one.
The Congo River in Africa is the deepest river in the world, and it's also one of the longest.
It runs through five different countries, and lots of animals live in it.
Turtles, African manatees, and dwarf crocodiles live there.
And so do more than 300 different species of fish, like the giant tigerfish and the squeaker catfish.
I don't think squeaker catfish, chase robot rats named Squeaks, but they're very far away from us, so you don't need to worry.
And rivers are always flowing to somewhere.
Look where the Congo River in Africa empties into, Squeaks, the Atlantic Ocean.
Yeah, this whole blue area here is the Atlantic Ocean, and over here is the Pacific Ocean.
Oceans are the largest type of body of water on Earth, and they are gigantic.
We're still exploring the oceans and making discoveries about all the kinds of animals that live there.
Exactly!
Like sharks and whales and octopuses!
Oceans are made of salt water, which people can't drink.
And neither can robot rats.
Almost all of the world's water is found in the oceans.
That leaves only a teeny tiny amount of fresh water that we can drink.
But we can find that fresh water in lots of different places.
Yep.
Like rivers and streams and lakes or ponds, which are bodies of water that are surrounded by land.
See this big blue area here in Siberia?
This is Lake Baikal, and it's one of the biggest freshwater lakes on Earth.
Everything blue on this map is water.
Yes, over 70% of the land on Earth is covered in water.
Rivers and streams and lakes and ponds and oceans and seas.
But sometimes water isn't a flowing liquid, like what comes out of our faucet.
Sometimes it's...
That's right!
Sometimes liquid water becomes solid ice.
Some parts of the Earth are covered with ice, like the snow on top of mountains.
Or glaciers!
A glacier is a giant buildup of ice and snow that slowly moves over land.
Most of the world's glaciers are in Antarctica, but almost every continent has glaciers.
In fact, Squeaks and I could go visit one if we wanted to.
There's a place near the fort called Glacier National Park, where we could go see a glacier.
You're right!
I think we should plan a trip.
Look at this, though.
Do you see these white parts at the top and the bottom of the map?
The Arctic Ocean at the top and Antarctica at the bottom are so cold that they're covered in ice all the time.
Uh, yeah, I think that's too cold for us to visit.
There sure are a lot of places that we can find water, and a lot of ways we can show where water is.
Water really is everywhere.
And talking about it has sure made me thirsty.
I think it's time for a nice glass of water.
Do you want to come to the kitchen and get some from the faucet?
Water.
Wind.
Water.
Wind.
Water.
Whoa.
Hi, Bill.
Hi, Webb.
What's going on?
Bill says that water is more powerful than wind, but wind is so much stronger.
No way.
Wind has nothing on water.
Wind and water are very powerful.
It sounds like you're both onto some impressive ways the surface of the Earth can change.
Wind and water can both change the shape of the land.
I have an idea.
Let's compare some of the ways wind and water can change the land, and then we can decide which one is stronger.
Well, okay, but how strong can water be anyway?
Strong enough to make one of the coolest places on Earth, water made the Grand Canyon.
That's right.
The Grand Canyon is a gorge, or a very deep place in Arizona.
It's so big and deep, you can see layers of rock going down around 1,800 meters.
You could stack six Eiffel Towers on top of each other from the bottom of the canyon and they would just about reach the top.
Wait, wait, wait.
The Grand Canyon is a giant hole in the ground.
What does water have to do with that?
Water dug that giant hole in the ground, Webb.
About five or six million years ago, two rivers flowed together to create the Colorado River.
But how does a river make a canyon?
Water is strong when there's a lot of it, and the Colorado River has a lot of water, especially when it floods with rain or snow from up in the mountains.
When the floodwaters come through, rocks get knocked into the river, scraping away at the other rocks underwater, making the river deeper and wider.
This is called downcutting, when the rocks moving down cut into the riverbed.
Even when it isn't flooding, there's erosion when the river water carries tiny pieces of the ground away downstream.
The river water erodes the land around it, cutting away bits of earth and rock bit by bit, until there's a grand canyon.
Wait, I'm in water all the time, and I don't get eroded.
Erosion takes a long time.
The Colorado River took millions of years to erode the Grand Canyon and it's still doing it, just a little bit at a time.
That's absolutely right.
Water can take a very long time to change the shape of the land, but it does it in a big way.
We've seen how strong water can be, but let's talk about wind.
All right, my turn.
Let me show you a place that has been shaped by wind.
This is the Namib Sand Sea in Namibia, part of the oldest desert on Earth.
It's home to some of the world's tallest sand dunes.
Dunes are huge piles of sand built by wind, usually found on a beach or desert.
Wait.
How does wind build anything?
It doesn't have hands and no shovels.
Sand is made of tiny pieces of rock, and those pieces are small enough for wind to carry.
When a strong wind blows over sand, it picks up pieces and carries them away.
The wind drops the bigger pieces of sand first.
Those pieces can be...
So when the wind brings more sand, more pieces will stick to them.
That's how a dune starts to grow.
And sometimes it can grow and grow and grow.
Wow.
That one's as big as a mountain.
Yeah.
Some of the dunes in the Namib Sand Sea are over 300 meters tall.
That's about 1,000 feet.
That's about one Eiffel Tower tall.
The dunes were built by wind for over a million years and they're still shifting with the wind today.
See?
That's why I think wind is stronger.
I still think it's water.
Both take a long time to create giant landforms or shapes in the land, like dunes or the Grand Canyon.
Actually, I know something that might settle this.
Have you heard of stone arches?
Not yet.
Are they made by water or wind?
Both.
Natural stone.
Arches are formed when water seeps into special types of stone, then freezes into ice and cracks the stone.
Over millions of years, the cracks continue until the rock is very thin.
Wind and water both work together to erode the rock, taking away lots of little pieces around the hole until what's left is an arch shape.
There are famous stone arches all over the world, like Landscape Arch in Utah's Arches National Park or the Shinrin Ferry Bridge in China.
So you're saying that water and wind... Can work together?
Yep, just like how you two do amazing things when you work together.
That's true.
Bill, thanks for helping me learn about water erosion.
No problem.
Thanks for helping me learn about wind building sand dunes.
Let's go learn more about arches.
Looks like Bill and Webb are going to have fun learning more about amazing landforms and the forces that shape them.
No, precipitation is the one where... Oh, hey there.
Squeaks and I are trying to solve a problem.
Squeaks is having some trouble remembering the different parts of the Earth's water cycle.
Earth's water is constantly being recycled, coming down from clouds as raindrops and snowflakes, running across the ground in streams and filling up puddles, and going back into the sky and forming more raindrops.
Scientists give these steps names.
Evaporation. condensation, precipitation, and collection.
Water goes through these steps over and over again.
Oh, that's okay, Squeaks.
Those are some new words.
And they sound pretty similar to each other.
Squeak says he keeps forgetting what happens in each step.
I'm trying to think of a way to help him remember.
Hey, I have it.
What about a play?
Sure, a play!
Plays are a fun way to tell stories, and we can write one telling a story about how water moves through Earth's water cycle.
Scientists often use models to explain things in the natural world that are hard to see or describe.
A play can definitely be a model.
And we can ask our friends if they want to help, too!
That's a great idea!
Squeaks wants to pretend to be water in the play and move through each step of the water cycle.
Let's ask our other friends to play the other roles of evaporation condensation, precipitation and collection.
Aw, thanks, Squeaks.
I would love to be the narrator for your play.
Let's get in touch with everyone to get this play underway.
And we'll see you at the performance.
Welcome, friends, to the story of water's amazing journey.
Let's follow water as it moves through the water cycle.
This adventure will take us hundreds of kilometers from sky to earth and back again.
Our story begins with the sun shining brightly on the ocean.
Water is resting on the surface of the ocean, enjoying the waves.
Hey, is it getting warm in here?
Or is it just me?
It's definitely getting warm.
Thanks to the sun's energy.
And when water gets warm enough...
It's time for you, Water, to join me, Evaporation.
Come on, let's begin your journey.
Water begins to feel kind of funny.
When water evaporates, it changes form.
It changes from a liquid to a gas called water vapor, and it rises.
Water feels himself starting to float into the air.
When water vapor is high in the sky, my work is done.
See you next time, water.
Water is now high above the ground in Earth's atmosphere.
Temperatures up here are much cooler than the warm temperatures that caused water to turn into vapor and evaporate.
Oh, hey water, you're back.
Looks like you evaporated from the ocean.
Did it wave goodbye?
Get it, wave?
Like the ocean has waves?
Anyway, you're here now, all ready for me.
Condensation.
When water vapor gets cool, it condenses.
It turns from a gas back into a liquid.
During condensation, water vapor sticks together to form small drops.
Small drops combine to form bigger drops and so on.
We can see the condensed water vapor in the sky as clouds.
And clouds are the starting point for the next part of water's journey.
Water doesn't usually.
And there are lots of kinds of clouds.
Feathery cirrus clouds, fluffy cumulus clouds and, my personal favorite, clouds that form storms cumulonimbus clouds.
Man, I could talk about clouds all day.
Psst, Sam.
Oh, sorry about that.
Stay cool until the next time I see you, water.
Or don't.
I mean, I guess since you have to be warm to evaporate?
Water doesn't usually stay in the clouds for very long before it moves into the next part of the water cycle.
That's right.
What once went up must now come down.
It's time for me, precipitation.
Precipitation forms when a water drop becomes too large to stay in a cloud.
Water starts to feel kind of heavy and falls from the cloud toward the Earth.
There are different kinds of precipitation, like rain, hail, and snow.
They're all made of water.
Which kind of precipitation forms depends on things like temperature and what kind of cloud the water is in.
Clearly, precipitation is a lot more exciting than evaporation.
That line wasn't in the script.
It's more interesting now.
Guys, guys, not right now.
Cool it.
Well, the show must go on.
Once precipitation lands on the Earth, it enters our final stage of the water cycle.
Collection, that's me.
You can use the term collection to describe all the different things that can happen once water falls and lands on Earth's surface.
You might land in a large lake or flowing river or freeze and become part of a glacier or polar ice cap.
You might land on dirt and sink into the ground Or Water, suddenly feels like he's starting to slide downhill.
Oh, neat.
It looks like you're going to be part of some runoff.
Runoff forms when water runs down mountains and hills into streams and the streams run into rivers that eventually end up flowing into an ocean.
Come back again when you can stay longer.
Maybe you can help one of my plants grow next time.
Before he knows it, water is back where his journey began.
The ocean.
What adventures will this water have during its next trip through the water cycle?
That's a story for another day.
Maybe one that you will write.
