|
What do you already know about clouds?
|
|
1
|
Press the Right Arrow below to go to the next page.
|
2
|
Press the Right Arrow below to go to the next page.
|
3
|
| Congratulations! You have completed this section. |
|
1
|
|
Big puffy white clouds, dark gray rain clouds. When you look up into the sky you could see many different types of clouds. They are not only pretty, they are also an important part of nature. In this unit, you will explore clouds, what they are made of, and their role in the water cycle. |
|
2
|
|
Have you ever lain on the beach or field and watched a huge
cloud float by? Were you amazed at how slowly it was changing?
|
|
3
|
|
|
|
4
|
|
|
Check all the words that describe the top clouds in the movie.
|
5
|
|
Sometimes it is in a liquid form: Water flows in a river, an
ocean, and in your sink.
Draw a picture of yourself doing something with liquid water. For example, swimming, drinking, walking in the rain. Take a snapshot of your drawing. |
|
|
6
|
|
|
|
In science, scale means how closely you are looking at something. For example, you've already studied clouds on a large scale by looking at an entire cloud and watching it move and change. We will also explore clouds on a very small scale by observing the tiny particles of which they are made.
Sometimes scientists use computer models to show things that are
difficult to see. In this unit, we'll use computer models to study
tiny bits of water.
This computer model zooms in from a large scale to a very small scale. At
the beginning, you can see an entire cloud. At the end you are looking at
individual water molecules, which are really too small to see.
Click the "Zoom In" button at the bottom of the picture to the right to
"zoom in" to the cloud. Zoom all the way in until you can't zoom any more.
The white circles represent water, the blue circles represent other parts
of air.
|
7
|
Congratulations! You have completed this activity. Click on the Home button below. Ask your teacher for further instructions.
|
Why are there clouds?
|
|
1
|
|
Read "What Are Clouds Made Of?" by using the forward and back buttons below. |
Can you predict what the story will be about?
Read the title and look at the pictures for clues about the story.
I predict the children will learn about clouds.
|
Chapter 1
|
2
|
"Where does the water go when we dry off?" asked Natasha. She was always asking questions.
"It doesn't go anywhere," her brother Marc said. "It just disappears."
"It can't just disappear!" said Natasha, frowning.
"Things don't just disappear."
"What about that rabbit?" asked Marc.
"What rabbit?"
"The one that disappeared into the hat when the magician waved his wand at that show."
"That's different," said Natasha. "That was magic."
|
3
|
"I don't think so," said Natasha. "Mom said that magic isn't real."
"You never know," said Marc with a knowing look. Actually, he wasn't sure where the water went, but he didn't want Natasha to think he didn't know something as simple as that.
To change the subject, Marc said, "That cloud looks like an elephant!" He pointed. "See, that's its trunk and that's—"
"What are clouds made of?" asked Natasha.
|
4
|
"Are you sure?" said Natasha, doubtfully. "You mean like we had at the fair?"
Marc was just about to tell Natasha to quit asking all these dumb questions when a shadow fell across them both. Turning his head to one side, he saw a tall lady standing over them.
"I wouldn't be so sure about that," said the lady, "though I do admit that some clouds look like cotton candy."
Let's make a connection. What do clouds look like to you?
Think back to a cloud you saw recently. Or look up to the sky and
describe a cloud.
Marc described a cloud that looks like an elephant. I have seen a
cloud that looks like a dragon.
|
Chapter 2
|
5
|
"Where did you come from?" asked Marc.
|
6
|
"What's the matter?" said the lady. "Don't you like my shoes?"
"Well, sure we do," said Marc, anxious not to annoy her. "It's just that…"
"I'm not wearing a swimsuit," the lady went on, "because I don't intend to swim. And I'm here because you, young man, told a fib!" She took off her sunglasses and stared at Marc with bright blue eyes that seemed to see right through him.
"What fib?" asked Marc, weakly.
"You said clouds were made of cotton candy!" answered Natasha. "I knew that sounded fishy."
"Well, if they're not cotton candy, what are they made of?" asked Marc.
"There's only one way to find out," said the lady, "and that's to go up there and see for yourselves."
"We can't do that," said Natasha. "We can't fly. We're not birds."
|
7
|
"My name is Elvira," said the lady. "What are your names?"
"I'm Natasha, and this is my brother, Marc." Natasha was beginning to like this person. She had a feeling that if she stuck with her, she might get some of her questions answered.
Elvira said, "Very pleased to meet you both!" She shook their hands and said, "You could fly to the clouds! Oh, yes. I could teach you how! But you'd have to really, really want to. And you'd have to be very brave, of course."
Marc wasn't sure what they were getting into, but before he could say anything, Natasha piped up, "We're brave! We're brave as anything! Just show us how to fly!"
"All right then," said Elvira. "Stand up."
|
Chapter 3
|
8
|
As Natasha and Marc did this, a curious thing happened. The sounds of the other children playing on the beach nearby seemed to fade away. So did the voices of the grownups. Even the yapping of two little dogs that were running in and out of the waves got softer and softer until they could no longer be heard. And as though a cloud were passing in front of the sun, the rest of the beach seemed to get darker somehow until it too faded away, and Natasha and Marc and Elvira were left in a little circle of sunshine all their own. It was almost as if they were the last people on Earth!
"There, that should do it," said Elvira.
"Whaa – what's going on?" asked Marc. "Where is everybody?"
"Oh, they're still there," said Elvira. "They're just not paying attention to us any more. No sense creating a sensation, you know! People are so curious!"
As she said this, Marc's shoulders started to feel itchy. It felt as though a family of ants were crawling all over them. "This is scary!" he thought to himself, but for some reason he didn't feel scared. He looked at Natasha. She didn't look scared, either. She just looked surprised. She was staring at him until her eyes nearly popped out of her head.
|
9
|
Sure enough, two little white wings were popping out from Natasha's shoulders. As Marc watched, the wings grew wider and longer. Pretty soon Natasha had the most beautiful wings he had ever seen! They looked like a bird's wings, only they were much bigger. By this time Marc's own wings had grown until they were as big as Natasha's. When he spread them out he could easily touch the ground with their tips on either side. He tried beating them up and down a few times just to see what would happen, but his feet stayed right where they were on the ground.
"What's the matter, Elvira?" he said. "Why can't I fly? What am I doing wrong?"
"You need to move your wings in little circles, not just up and down. Oh, yes!" said Elvira.
Somehow she had sprouted wings, too, while the children weren't watching, or maybe she had had them all along. "Hunch your shoulders forward when you bring your wings down, like this."
Elvira demonstrated. Slowly she rose in the air about ten feet and remained there, beating her wings and smiling down at the kids.
|
10
|
But it was hard work! They had to keep beating their wings in order to stay up and it was even harder if they wanted to climb. In no time at all they were out of breath and panting.
"How do the – puff, puff! – birds do it?" asked Marc. "They hardly seem – puff! – to move their wings at all."
|
11
|
"What are thermals?" asked Marc. He didn't really care what they were, but the idea of letting the air do the work appealed to him.
"They're places where the air rises," said Elvira. "Here, let me show you." She flew toward the beach. "Let's see. They're usually found above hot places like the hot sand on the beach. Ah, here's one! Watch me!"
Elvira spread her wings way out and stopped beating them. Amazingly, she started to go up. She tipped her wings just a little and turned to the left. She kept turning and rising. It looked easy, just as though she were going up an invisible elevator in the sky! When she got to a hundred feet or so, she stopped turning and swooped down toward the children.
"Now you try it!" she said. Natasha and Marc rushed to the spot where they had seen Elvira start her climb. Sure enough they didn't have to beat their wings very much to stay up. As long as they stayed over that spot they could just keep on climbing with practically no effort.
"This is cool!" said Natasha.
How do you think the children feel?
Take a close look at the picture for clues.
Marc and Natasha look happy to be flying.
|
Chapter 4
|
12
|
"Remember how all this started," she said. "Natasha wanted to know what clouds are made of."
"And you said we'd have to visit them to find out," Marc said. "Were you serious? Could we really fly that high?"
"See that cloud?" said Elvira, pointing to a small fluffy cloud directly overhead. "Those low puffy ones are called ‘cumulus' clouds. I bet it's not more than a mile up. We can do it easily. Yes we can!"
A mile sounded like quite a lot to Marc, but before he could say anything Natasha and Elvira had started to climb the thermal. He followed them, wondering why Natasha seemed to trust Elvira so much. She would follow her anywhere, it seemed.
The three of them flew up and up. It hardly took any effort at all, just a nudge of their wings every once in a while to make sure they stayed inside the column of rising air. The beach below them got smaller and smaller and they could see the houses behind it and a long highway behind the houses. They had driven on that highway to come out to the beach from the city where they lived.
|
13
|
"Look who's asking questions now!" teased Elvira. "They're called thermals. It's really all about energy! Energy! Energy! I love talking about energy!" Marc wondered where Elvira got all of her energy. Elvira continued. "There are so many forms of energy in the world, and they all do work! Did you ever feel like you had so much energy that you wanted to go run around?"
"All the time!" said Marc. "Well, running is a type of work for your body. Thermals form when some air has more heat energy than the air nearby. The air by the beach gets heat energy from the hot sand, so it has more energy than the nearby air over the water. Most people say, ‘It's hotter.' I like saying, ‘It has more heat energy!' With all that energy, it just has to do work, and the way hot air works is by moving up away from the earth! Isn't it amazing?"
Even though Marc didn't quite understand Elvira, he was amazed that the energy in the air was enough to lift him and Natasha so far into the sky.
|
14
|
As they climbed higher, the temperature became colder and colder. Pretty soon Natasha and Marc were shivering and their teeth were chattering. Elvira didn't seem to mind the cold, but when she noticed that the children were cold, she reached into her backpack and brought out two cloaks. They were made of some thin material and had holes where the wings could poke through. They were very light, but also very warm. In a minute Natasha and Marc were comfortable again.
As soon as her teeth stopped chattering, Natasha asked, "Why is it colder higher up?"
|
15
|
"I know, but why?" When Natasha had a question she was like a dog with a bone – she just wouldn't let go till she was satisfied with the answer.
Elvira seemed to sense this. She took the time to give Natasha a good answer. "Remember how hard it was to fly high before you discovered thermals?" she asked. Natasha nodded. "So think how hard you would have had to work to make it all the way up here! It would have taken all your energy to do that, yes sir! Well, the air has to use up a lot of its energy to rise, and the energy in air is in the form of heat. That hot air down there on the beach had a tremendous amount of energy. That's how it could lift us all the way up here. But it lost a lot of its heat energy climbing and pushing us up and that's why it's gotten so cold. In fact, that's what it means for something to get cold: it has lost its heat energy."
"I love this," whispered Natasha to herself.
"Me, too," said Elvira, smiling at Natasha and Marc.
|
Chapter 5
|
16
|
"It looks like a fog bank!" she said.
"A what?" asked Marc. "A bank for fog instead of money?"
"No, no," said Natasha. "Remember when we were at grandma's that time and it got foggy all of a sudden? That was because a fog bank came rolling in off the ocean. One minute it was perfectly clear and the next minute you couldn't see two feet in front of you."
"Oh yeah, now I remember," said Marc. "It was spooky!"
"Well, this may be a little spooky, too," said Elvira. "You two stay real close to me, you hear? We're about to enter the cloud. There's nothing to be afraid of. We'll just keep going up and we'll pop right out the top."
|
17
|
Natasha and Marc held very tightly to Elvira's hands. The wind was very fierce now and it was getting really foggy. Looking down, Natasha could no longer see the beach and the houses and the highway. Everywhere she looked she saw nothing but grey fog. Even Marc, who was only a few feet away holding Elvira's other hand, was beginning to disappear into the fog. Natasha's face and hands were getting wet. The wind was howling in her ears. She squeezed Elvira's hand as tightly as she could.
How do you think the children feel now?
Read the text carefully for clues.
The text says that Natasha held very tightly to Elvira's hand. I
think she is afraid because she can't see anything.
|
Chapter 6
|
18
|
Elvira's voice was soothing. It seemed to come to Natasha from inside her own head, cutting through the noise of the wind. "It's all right," said Elvira. "It's not dangerous. In fact, it's really interesting, oh yes!"
"Will we be in it long?" asked Marc. His voice seemed to Natasha to be coming from far, far away.
"Not very long," answered Elvira. "Cumulus clouds tend to be smaller than their tall cousins, cumulonimbus! Those clouds can go for miles! This is just a little cloud and the air is still rising inside it. We should be through it in just a few minutes."
Natasha was still a little scared, but she had to admit this cloud was indeed pretty amazing! Her curiosity overcame her fear. "Why am I getting so wet?" she asked.
"Remember your question that started this whole journey?" said Elvira. "Well, now you've got your answer."
"You mean clouds are made of water?" said Natasha. "That's really weird!"
"I knew they weren't really cotton candy," said Marc. "I was just fooling. But there's something I don't understand. If clouds are made of water, where does the water come from?"
|
19
|
"But I didn't see any water on the way up," said Natasha. "And water doesn't have wings. Water can't fly like a bird. That doesn't make sense!"
"Of course water can fly!" said Elvira. "Think back. What were you doing before you asked what clouds were made of?"
"We were looking for shapes," Marc remembered. "I saw a cloud that looked like an elephant, and…"
"No, before that," said Elvira. "Natasha asked a different question, remember?"
"We were drying off," said Natasha, "and I asked where the water went. And Marc said it just disappeared."
|
20
|
"Invisible?" asked Marc. "How does it do that?"
"When water absorbs heat energy from the sun's rays it changes from a liquid into a gas," said Elvira. "We call this change ‘evaporation.' The gas is called water vapor. You can't see it, but water vapor is part of the air all around you."
|
21
|
"If water vapor is invisible," she asked, "why can we can see clouds?"
Marc had the answer. "Because clouds aren't made of water vapor!" he said, triumphantly. "They're made of regular, liquid water! That's why our faces and hands have been getting wet."
|
22
|
"When the air gets cold, the water vapor in it gets cold, too," Elvira went on. "So the water vapor changes back into little liquid droplets. That's called ‘condensation.' Condensation is the opposite of evaporation."
Elvira was on a roll. "You might also be curious to know that cold water vapor by itself has a hard time becoming a liquid, or I should say ‘condensing,' unless it has a tiny piece of dust to cling to. At the center of each water droplet in a cloud is a tiny piece of dust."
"You mean clouds are just lots and lots and lots of little water droplets clinging to dust?" asked Natasha.
"Yes, and sometimes little bits of ice, too. You know those really high, wispy clouds? Sometimes they look like feathers? Those are cirrus clouds and they are mostly ice," said Elvira. "But I don't see any ice in this cloud. I guess it isn't cold enough."
"It's plenty cold enough for me," said Marc.
"Me, too," said Natasha.
|
23
|
Just then they popped out of the cloud. It was quite sudden. The sun shone brightly. The warmth of the sun felt good on their backs. The puffy cumulus cloud was just below them.
"You know what?" said Marc. "Even though we've just been through it and we know it's made of water, it still looks like cotton candy!"
"Notice something else?" asked Elvira. "Our thermal is gone!" Sure enough, they had stopped climbing and they had to flap their wings to keep from falling back through the cloud. "The air kept on rising and cooling until it cooled so much that it couldn't rise any more," said Elvira.
They all looked around in silence, then Elvira said, "Now that we're in this amazing place, I think you two are ready to learn a secret. If you hear people talk about clouds and you hear ‘nimbo' or ‘nimbus,' it means a type of cloud that makes rain," said Elvira.
|
24
|
Elvira beamed. "Welcome to the club, Marc and Natasha." Even though they usually argued, Marc and Natasha smiled at each other, but only for a second.
"How are we going to get back down?" asked Natasha, a little uncertainly. "I bet Mom and Dad are missing us!"
"Don't worry about them," said Elvira. "They won't notice a thing. As for getting back down," she went on, "we could fly down or if you two are getting bored..."
"Oh, we're not bored!" said Natasha, "It's just that…"
"I understand," said Elvira, "It's been fun, but now you'd like this little adventure to end. Of course you would! And we can do that, too. Just hold my hands real tight and close your eyes."
|
Chapter 7
|
25
|
"Where is she?" he asked. "What happened to Elvira?"
"I think she's gone," said Natasha, sadly. She checked her own back, but she knew what she would find. Sure enough, her wings were gone, too.
Marc was looking around. "Look!" he said "She didn't even leave any footprints in the sand. It's as though she wasn't real!"
"But we know she was here," said Natasha, "and we know we flew up into that cloud and got water in our faces. We know it really happened, right?"
"Uh, right," said Marc. But he sounded a little doubtful. A drop of water hit Natasha on the shoulder. Then another one hit the other shoulder.
"Children," called their mother, "it's starting to rain. Get your things together, we're going home!"
Think about your parents and siblings, your teachers, your coaches,
and your friends.
Let's make a connection. Who teaches you new things?
Lots of people teach me new things all the time!
|
Chapter 8
|
26
|
"I'm sure it was real!" Natasha whispered to Marc. "I'm just sure of it!"
"Then how come no one noticed?" asked Marc. "We were gone a long time. How come no one missed us?"
"I don't know," said Natasha. "It was magic, I guess."
"You said there was no such thing," Marc reminded her.
"But Elvira is different," said Natasha. "She's real magic!"
"If she even exists!" said Marc, but he said it so softly that Natasha didn't hear him.
Suddenly Natasha had another question!
|
27
|
"What water?"
"The water in the clouds."
"I don't know," said Marc. "Maybe it just turns back into water vapor and becomes invisible again."
"But then sooner or later all the water in the world would end up in the air," said Natasha. "I don't get it."
Suddenly a familiar voice sounded in Natasha's head. "Look around you," the voice said. "Where do you think all that rain came from?"
Natasha looked at Marc and Marc looked at Natasha. They smiled. Natasha could tell that Marc had heard the voice, too.
"Now I see," said Natasha. "The cloud dumps its water on us and we call it rain! This could be a cumulonimbus cloud we're driving under!"
"And then the water heats up and evaporates and turns into water vapor. And then it goes up in the air and condenses and turns back into a cloud," said Marc.
Let's make a connection. Have you solved a mystery or completed a puzzle or crossword?
Think about games you play or stories you read.
The children solve a mystery by putting together all the facts they've learned about clouds and water.
|
28
|
"The water that evaporated from our bodies this afternoon might be raining on the car right now!" said Marc, with amazement.
Their mother turned around to look at them. "What are you children talking about?" she asked.
"Oh, nothing," said Marc. "We were just wondering about clouds."
|
29
|
"And we were wondering about Elvira!" whispered Natasha. "She is real, after all!"
"I guess she is," said Marc.
Press the Right Arrow below to go to the next page.
|
30
|
Congratulations! You have completed this activity. Click on the Home button below, then ask your teacher for further instructions.
List everything from the story about water, clouds, and the world that you think is true.
List everything from the story about water, clouds, and the world that you think is false.
|
What are clouds made of?
|
|
1
|
|
In this activity, you will learn how to identify different types of clouds. |
|
Engage
|
2
|
| This activity is all about identifying clouds, so let's start by looking at the clouds outside. Look out the window and draw the clouds you see. If there aren't any clouds today, try drawing the different clouds in the photo. Take a snapshot of your drawing. |
|
|
|
|
3
|
|
|
|
|
Explore
|
4
|
The naming of clouds can be confusing at first, but to get started all you need to learn are three words or parts of words. Let's practice saying these words and parts of words. Highlight each word. Listen to how to say it. QUIETLY repeat the word out loud.
|
|
|
| cumulus | stratus | cirrus |
|
5
|
|
|
|
| altocumulus | stratocumulus | cumulonimbus |
|
6
|
|
Remember that clouds form when air cools. Air usually cools as
it rises higher in the sky.
One reason air rises is that heat from the sun warms the land and water at different rates. The air over the land becomes warmer than the air around it, so a “thermal” forms, a rising section of warm air. As the thermal rises, the air expands and cools. When it has cooled enough, the water vapor condenses into liquid droplets. |
|
|
7
|
The motion of the thermal creates the puffy shape of cumulus clouds.
Sometimes air rises because it gets gently pushed by another body of air. This can cause clouds that are spread out and layered. These are called stratus clouds.
If the air is pushing strongly enough and the bodies of air are tall enough, then the air rises higher in the sky. At that height, the temperature is so cold that the clouds are made of ice crystals. These are called cirrus clouds.
If the thermal is rising very fast and the air is very humid, they can grow very tall and become dark gray storm clouds, called cumulonimbus.
They are a bit like stratus and a bit like cumulus clouds, so we call them stratocumulus clouds.
|
8
|
|
9
|
cumulus cloud |
cumulonimbus cloud |
Some clouds are mostly bright white and other clouds are a dark gray color. The clouds in the photo on the left are cumulus clouds. Sometimes a cumulus cloud grows very tall from strong rising thermals and becomes gray. In the right photo, the cumulonimbus cloud is gray because it contains so much water that light can not pass through it.
|
|
|
9
|
Now, let's look at the height of different types of clouds. We call the height of a cloud its "altitude."
|
|
|
|
Some clouds are low to the ground, about 2.1 km/ 7,000 feet high. Cumulus and stratus clouds are low to the ground because there is not enough energy to push them higher in the sky. |
|
Some clouds are a medium height, between 2.4 - 4.9 km/7,000 and 16,000 feet above the ground. For medium height clouds, we add "alto" to the name, so these are called altocumulus. Altocumulus clouds form at a medium height because the rising air has more energy. The cooling bodies of warm air that form the altocumulus clouds have risen higher before condensation occurs. |
|
Some clouds are very high up, over 4.9 km/16,000 feet above the ground. Bodies of air with enough energy to reach this height form clouds of ice crystals due to the extreme low temperature at that altitude. When clouds are very high in the sky, they are called cirrus clouds. |
|
|
Explain
|
10
|
(low clouds)
(very high clouds)
(tall clouds)
(low clouds)
(medium height clouds)
(low clouds)
|
11
|
|
Elaborate
|
12
|
|
|
|
|
13
|
Congratulations! You have completed this activity. Click on the Home button below, then ask your teacher for further instructions.
|
What is the name of that cloud?
|
|
1
|
|
|
Engage
|
2
|
|
|
|
1. water in the ocean
2. water vapor in the air
3. clouds forming in the sky
4. snow on mountain tops
5. rain falling to the ground
6. water absorbed by plants
7. water deep in the ground
8. water in a lake
|
3
|
Sometimes water is a liquid, sometimes it is a solid, and sometimes it is a gas. These changes in the states of matter are the result of the water either gaining or losing energy. These changes are very important for the water cycle.
|
4
|
|
Some of the earth's liquid water is deep under the ground,
in cracks between rocks. We call it ground water. Some
ground water is thousands of years old and some is only a
few weeks old. Ground water comes mostly from rain and
melting snow.
|
|
|
5
|
Does all water that touches the ground become ground water? This is not necessarily the case. Ground water is water in the rocks deep in the ground. Water in a puddle is not ground water. Since a puddle is on the surface of the earth, we call it surface water. Rivers and lakes are also surface water. Lots of water touches the ground, but not all of it is ground water.
|
6
|
|
|
|
|
Explore
|
7
|
|
Here is a model showing the water cycle. Run the model and
notice how water travels around and changes from one form to
another.
Click the " run/stop " button to set the model into action. Experiment with the buttons and sliders to see how the model works. When you are ready, go on to the next page. |
This model was created using NetLogo. Go
here
to explore the model on your own.
|
|
8
|
|
|
|
On the following pages, choose the correct response for each model symbol.
|
Explore
|
9
|
|
Use the model to explore the questions below. Take a snapshot
of your model when finished.
|
This model was created using NetLogo. Go
here
to explore the model on your own.
|
|
10
|
|
|
This model was created using NetLogo. Go
here
to explore the model on your own.
|
In the next few pages, you'll explore the effects of wind on the water cycle.
Try your idea and take a snapshot of the result. This snapshot will be saved in your Lab Book.
In your Lab Book, add a note describing your snapshot.
Try your idea and take a snapshot of the result.
In your Lab Book, add a note describing your snapshot.
|
Explain
|
11
|
|
12
|
|
Elaborate
|
13
|
|
14
|
Congratulations! You have completed this activity. Click on the Home button below, then ask your teacher for further instructions.
|
How does water travel around Earth?
|
|
1
|
|
In this activity, you will investigate the humidity over
several simulated environments including oceans, forests,
icecaps, and deserts.
|
|
Engage
|
2
|
|
Humidity is a measure of the amount of water vapor in the air. While
water in the air is only a small amount of the Earth's water, our
planet would be very different without it. If the Earth's air didn't
contain water, our weather would be like that of Mars. It would have
no clouds except dust, no rain, no sleet or snow, and no fog.
|
|
|
3
|
|
An ocean is a large body of salt water. In this activity, you will
use water in a cup to simulate the ocean.
|
|
|
A forest is an area where most of the plants are trees. In this
activity, you use will grass or plants in a cup to simulate the
forest.
|
|
|
An ice cap is an area usually covered in ice year round, like the
tops of mountains or at Earth's poles. In this activity, you will
use ice in a cup to simulate an ice cap.
|
|
|
A desert is an area that has very little rain throughout the year.
In this activity, you will use sand in a cup to simulate the
desert.
|
|
|
Explore
|
4
|
|
Let's start by placing five clear plastic cups in a row. Using
masking tape and a permanent marker, make labels reading
forest, desert, ocean, ice caps, and control. The control
label will be placed on an empty cup so that you can compare
all of your measurements to the air in your classroom.
Now fill each individual cup 1/4 full according to their labels. The control cup will be left empty. |
|
|
5
|
|
6
|
|
Now you need to construct a way to measure the humidity over each environment.
Your teacher will help you cut away the top third of a clear plastic bottle. |
|
|
7
|
|
Remove the cap from the bottle and place the humidity sensor
through the opening of the bottle.
Secure the humidity sensor to the bottle with clay. |
|
|
8
|
|
|
|
Before you begin measuring, look at this sample humidity graph and answer the questions to be sure you understand how to read it.
The units are percent. 0 percent means there is no water vapor in the air at all. 100 percent means the air has as much water vapor as it can hold at that temperature.
on the right.
|
9
|
|
|
|
Record it in the table below, in the bottom row marked control, under the humidity column.
Record it in the table below, in the bottom row marked control, under the humidity column.
|
10
|
|
|
|
Record it in the table below, in the bottom row marked control, under the humidity column.
|
11
|
|
|
|
Record it in the table below, in the bottom row marked control, under the humidity column.
|
12
|
|
|
|
|
13
|
|
|
|
Record it in the table below, in the bottom row marked control, under the humidity column.
Remember it is okay if your prediction and results are different! This is a chance for you to learn something because of the measurements you took.
|
Explain
|
14
|
|
|
|
Elaborate
|
15
|
|
“Heat islands” are created when growing cities change the
environment by substituting forests with roads, parking lots, and
roofs of buildings. Trees provide shade and cool the air through
evaporation. The hard, dark surfaces like pavement in this picture
store heat during the day, heat that is then released at night,
keeping the city hotter for longer periods of time.
|
|
16
|
|
17
|
|
The city of Chicago is experimenting with a new architecture
they call “green roofs.” On several city buildings they
replaced the black tar surface with soil and plants. The
photo shows the roof of the Chicago City Hall. These green
roofs have worked well to keep the buildings cooler in the
summer.
|
|
18
|
Congratulations! You have completed this activity. Click on the Home button below, then ask your teacher for further instructions.
|
What does humidity have to do with clouds?
|
|
1
|
|
In this activity you will explore a computer model that shows how water goes into the air and forms clouds. |
|
Engage
|
2
|
|
The atmosphere consists of many gases including water vapor.
Water vapor is invisible until it forms clouds. And even
though you can't see it, there is dust in the atmosphere. Dust
plays an important role in condensation that forms clouds.
|
|
|
3
|
|
All matter in the universe is made of very tiny particles,
called atoms. Atoms are grouped in special ways to form
slightly larger (but still very tiny) particles, called
molecules. Suppose you have special glasses and can see the
individual water molecules in a puddle.
|
|
One molecule on each side has a dotted line that shows its path as it moves.
You can also use the "Stop" and "Reset" buttons to control the model.
In your Lab Book, add a note describing your snapshot.
|
Explore
|
4
|
|
|
This model was created using Molecular Workbench created by
the Concord Consortium.
|
|
5
|
| In the model, the left side represents a LIQUID . The molecules slither and slide around, but stay close to each other. |
|
| In the model, the right side represents a GAS . The molecules are far apart and are moving very fast all the time. They bounce off each other. |
|
|
6
|
|
|
This model was created using Molecular Workbench created by
the Concord Consortium.
|
Run the model.
While the model is running, click the Add heat energy button five times and notice the changes.
In your Lab Book, add a note describing your snapshot.
|
7
|
|
|
This model was created using Molecular Workbench created by
the Concord Consortium.
|
We usually call this cooling, but it is more accurate to think of it as a loss or removing of heat energy.
Run the model.
While it's running, click the Add heat energy button ten times.
In your Lab Book, add a note describing your snapshot.
|
8
|
|
You probably noticed that when the gas on the left side is
cooled down, the molecules clump together because they aren't
going as fast. This is called condensation. This is what
happens when water vapor forms into water droplets.
When these "clumps" are big enough, we can see them as water droplets. That's what fog and clouds are -- water droplets in the air. The water droplets are usually so small that they float in the air. And when they are big droplets, they can fall as rain! |
|
|
Explain
|
9
|
|
This model is slightly different than the last one. It has a
temperature slider.
Run the model and experiment with the temperature slider. Take snapshots at different temperatures and note the differences in your Lab Book. |
This model was created using Molecular Workbench created by
the Concord Consortium.
|
|
10
|
|
11
|
You responded:
Here's a chance to show what you've learned from this activity. How do you answer the same question now?
|
12
|
Notice that the model now has an "Add Dust Particles" button.
Run the model and while it's running, add dust by clicking the Add Dust Particles button. (Click it only once.)
Add a note in your Lab Book describing your snapshot.
|
Elaborate
|
13
|
|
|
This model was created using Molecular Workbench created by
the Concord Consortium.
|
|
14
|
|
Congratulations! You have completed this activity. Click on the Home button below, then ask your teacher for further instructions.
|
How are clouds formed?
|
|
1
|
|
Have you ever heard a weather forecaster say, "Today it will be partly cloudy"? How many clouds does it take to be partly cloudy? In this activity, you will develop a method to calculate cloud cover in the sky. |
|
Engage
|
2
|
Go outside and look at the sky but not directly at the sun. Caution: Severe damage to the eyes may result! Try estimating the cloud cover.
|
3
|
|
|
- 0 = almost no cloud
- 1 = about half cloud
-
2 = mostly all cloud
|
4
|
|
|
Percent Cloud Cover Table
|
|
Explore
|
5
|
Now take your
own
measurement of cloud cover. First set
up your mirror.
|
|
Remember to not look directly at the sun. Caution: Severe damage to the eyes may result!
Note: you can avoid looking at the reflected sun by keeping the mirror in your own shadow.
- 0 = almost no cloud
- 1 = about half cloud
- 2 = mostly all cloud
|
6
|
|
|
|
7
|
|
|
Percent Cloud Cover Table
|
|
Explain
|
8
|
|
Elaborate
|
9
|
Congratulations! You have completed this activity. Click on the Home button below, then ask your teacher for further instructions.
|
How much of the sky is cloudy?
|
|
Why are there clouds?
|
1
|
|
Now it's time to review and summarize what you have learned
about clouds. To help, you can show all of your snapshots and
some of your written answers from the activities. They are all
in your Lab Book.
Review the questions on the following pages. There is a separate page for each activity that you worked on. Be prepared to share your answers with the rest of the class. |
|
|
Story: Wondering about clouds
|
2
|
|
Water cycle model
|
3
|
|
Making clouds
|
4
|
|
Cloud detectives
|
5
|
|
Humidity
|
6
|
|
Cloud cover
|
7
|
|
Summary
|
8
|
|
9
|
Let your teacher know that you are done. Your teacher will give you a password so you can take a short test.
| Password: |
|
Wrapping up
|
|
1
|
Press the Right Arrow below to go to the next page.
|
2
|
Press the Right Arrow below to go to the next page.
|
3
|
Press the Right Arrow below to go to the next page.
|
4
|
Press the Right Arrow below to go to the next page.
|
5
|
Press the Submit button when you are done.
|
What have you learned about clouds?
|