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The Case of the Phenomenal Weather

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Subido el 28 de mayo de 2007 por EducaMadrid

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NASA Why? Files video containing the following twelve segments. NASA Why? Files segment explaining how air pressure affects weather. NASA Why? Files segment describing different cloud types and how they form. NASA Why? Files segment explaining how the fut

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Hi, I'm Tony Perkins, weatherman for ABC's Good Morning America. 00:00:00
Every day I try very hard to give you an accurate, up-to-date forecast. 00:00:18
But weather forecasting is not always easy. 00:00:22
That's why I rely on math, science and technology to determine what the weather will be like 00:00:25
around the nation and in your neighborhood. 00:00:30
So tune into the NASA Y-Files, learn about meteorology and watch the Treehouse Detectives 00:00:33
as they solve the mystery of the case of the phenomenal weather. 00:00:39
On the Y-Files Club, we yearn to learn and want to see everything that we can be. 00:00:59
So come join us on our journey, don't you touch that dial, and welcome to the NASA Y-Files. 00:01:06
In the case of the phenomenal weather, join the Treehouse Detectives as they answer the 00:01:19
following questions. 00:01:24
How do clouds form? 00:01:26
What are the three main types of clouds? 00:01:29
What is air pressure? 00:01:32
And remember, when you see this NASA Y-Files logo, it's a sign that the answer is near. 00:01:34
Okay, done. 00:01:43
What are you building? 00:01:46
Oh, I'm building a roller coaster, so we'll all be prepared for the physics fair. 00:01:47
That's right, the physics fair at Busch Gardens Williamsburg. 00:01:51
Can you believe we get to spend the entire day riding roller coasters and figuring out 00:01:55
the physics behind it? 00:01:58
Here, use this tool. 00:02:00
Thanks. 00:02:02
I just happen to have my encyclopedia with me. 00:02:03
Is he joking? 00:02:06
I don't think so. 00:02:08
Did you know that on the Apollo's chariot, it drops 210 feet on the first hill, and it 00:02:10
reaches top speeds of 73 miles per hour, and you experience 26 seconds of weightlessness. 00:02:16
Wow, that's 26 seconds of feeling like a NASA astronaut. 00:02:22
Are you okay? 00:02:27
Yeah, I just can't wait to go to the physics fair next week. 00:02:28
We're not getting rained out this time, you're wet. 00:02:32
From the Weather Channel, I'm Lisa Moser. 00:02:35
The forecast calls for lots of sunshine, warm temperatures, and no rain, so get out there 00:02:37
and enjoy the nice weather. 00:02:42
However, down south, there is some activity in the tropics, a tropical wave located several 00:02:44
hundred miles off the coast of Africa is moving northwest currently. 00:02:49
This mass of thunderstorms is very unorganized, so further development is not likely at this 00:02:54
time. 00:03:00
Our weather team will closely monitor the progress of this system. 00:03:01
At least she didn't say rain. 00:03:05
I think we need to try and figure out the long-range forecast. 00:03:08
We might get to go to Florida if we win the environmental contest. 00:03:11
But that tropical depression might head to Florida. 00:03:14
Have you heard yet for the winners? 00:03:17
Not yet, but they'll be announcing it soon. 00:03:19
This is looking better. 00:03:21
What are the chances of it raining next week? 00:03:23
Weather isn't always predictable. 00:03:25
There are so many different things that could change a forecast. 00:03:26
I think we need to play it safe. 00:03:30
Let's organize what we know. 00:03:31
Let's go to the problem board. 00:03:32
What do we know? 00:03:37
We know the problem. 00:03:38
A tropical wave is now located hundreds of miles off the coast of Africa. 00:03:39
I heard that on our weather report. 00:03:43
And we also know that the tropical wave is not a threat to us. 00:03:45
I'll look outside. 00:03:48
No clouds in the sky. 00:03:49
That's a good sign. 00:03:50
Sometimes there are a lot of clouds, but it doesn't rain. 00:03:52
That's true. 00:03:55
I never thought of that. 00:03:56
Maybe we need to know more about clouds. 00:03:58
I'm looking at the NASA Langley website. 00:04:00
There's a program listed called School. 00:04:02
My school participates in that program. 00:04:04
And it's really cool. 00:04:06
We make weather observations and describe the types of clouds. 00:04:07
Well, what are we sitting around for? 00:04:10
Let's print off a get-up-and-go sheet from the NASA Wildflowers website. 00:04:12
We're supposed to meet Dr. Lynn Chambers. 00:04:16
There she is. 00:04:18
Hello, Dr. Chambers. 00:04:20
Treehouse detectives? 00:04:21
I've been expecting you. 00:04:22
Thanks for seeing us. 00:04:24
Well, we wanted to learn more about clouds and what they mean. 00:04:25
Do you know how a cloud is formed? 00:04:28
Not really. 00:04:30
I always thought it was when the sun sucks up a lot of water. 00:04:31
Then the clouds are formed. 00:04:34
Good guess. 00:04:36
But maybe I can explain it to you a little better if I make a cloud for you. 00:04:37
You can make a cloud? 00:04:40
Do we get to go up in an airplane? 00:04:42
No. 00:04:44
We can do it right here. 00:04:45
First, we'll fill this jar with water. 00:04:46
We need about 2 centimeters of water. 00:04:48
Did you know that 2.5 centimeters is equal to 1 inch? 00:04:50
Then we place some ice cubes in this metal tray and place it on top of the jar. 00:04:54
The air inside the jar will cool and the water vapor in the air will condense. 00:04:58
What does condensed mean? 00:05:03
Have you ever been outside on a really cold day? 00:05:05
No. 00:05:07
What happens when you breathe? 00:05:08
My breath looks like smoke. 00:05:10
That's condensation. 00:05:12
Your breath contains water vapor just like the air does. 00:05:13
Oh, that reminds me. 00:05:16
We forgot to add particles. 00:05:17
Do you see a cloud yet? 00:05:19
I see water drops forming. 00:05:20
The water condensation on the jar is not a cloud. 00:05:22
We need to add something for the water to condense on. 00:05:25
Any ideas? 00:05:28
Um, how about some dust from my room? 00:05:29
Or how about chalk dust? 00:05:32
How about some dust from my room? 00:05:34
Or how about chalk dust? 00:05:36
It might work. 00:05:38
We could use a number of things. 00:05:39
In the real world, it would be sea salt, dust, volcanic aerosols, or man-made pollution. 00:05:41
Since we don't have any of those here, I'm going to use a match. 00:05:47
This is the part where you need an adult. 00:05:50
So what will happen? 00:05:52
Let's give it a try. 00:05:54
I can see a cloud forming. 00:06:04
How do we know that's just not the smoke from the match? 00:06:06
We can shut off the condensation and make the cloud disappear by simply taking the ice away. 00:06:09
Do you want to try it? 00:06:14
Sure. 00:06:15
It vanished. 00:06:20
The cloud we made looked very wispy. 00:06:21
But in the sky, we see all different kinds of clouds. 00:06:23
Are there different types? 00:06:26
Yes, there are three main cloud types. 00:06:27
Cirrus, cumulus, and stratus. 00:06:29
Cirrus clouds are high clouds that form above 6,000 meters. 00:06:32
What are those round, puffy clouds that look like cotton candy? 00:06:36
Those are cumulus clouds. 00:06:39
They're found at different heights. 00:06:41
They're often seen on dry, sunny days. 00:06:43
What do you call those little clouds that cover the sky? 00:06:45
Those are stratus clouds. 00:06:47
Their base is usually found at low levels below 500 meters, 00:06:49
and they form a layer or sheet across the sky. 00:06:52
Do different types of clouds indicate different types of weather? 00:06:54
Some clouds do indicate different types of weather. 00:06:57
Some clouds do indicate different types of weather. 00:06:59
One of our treehouse detectives' class belongs to your cloud club? 00:07:01
Yeah, it's called School for Students' Cloud Observations Online. 00:07:04
We have 1,000 schools around the world where students observe clouds. 00:07:08
They send their data to a NASA computer, 00:07:12
and their observations are compared to those from Sirius instruments flown on satellites. 00:07:14
So kids actually help NASA? 00:07:19
Yes, we use the students' data to help us identify clouds 00:07:22
that the satellite has trouble seeing. 00:07:25
That is way too cool. 00:07:27
Just think, kids are actually helping NASA. 00:07:29
Thanks, Dr. Chambers. 00:07:31
Wow, we learned a lot from Dr. Chambers. 00:07:35
I wrote this for my trip. 00:07:38
Don't forget to add water vapor and condensation. 00:07:40
I know that's a clue, because it's how rain is made. 00:07:43
Hi, where's Dr. D? Is he here today? 00:07:46
We haven't seen him yet. 00:07:48
Hi guys, I'm here. 00:07:50
You have that look like you're working on something. 00:07:52
We're concerned about missing our physics fair because of the storm. 00:07:54
We don't want to miss riding those roller coasters. 00:07:57
Can you give us some clues on how to understand the weather? 00:08:00
Sure. Something you definitely need to understand is energy. 00:08:03
There's an electric motor that provides the energy to raise a roller coaster car 00:08:06
to the top of the first hill, and then gravity takes over. 00:08:10
What energy source makes the weather happen? 00:08:13
Do you mean what makes the winds blow? 00:08:16
Or what raises the rain into the clouds, just like the roller coaster was lifted? 00:08:18
Exactly. 00:08:23
I don't know. 00:08:24
I think you do. It's the same energy source that makes the plants grow. 00:08:25
Oh, the sun. I knew that. 00:08:29
When the sun heats the earth, some areas become hotter than others. 00:08:31
It's this uneven heating that produces the winds. 00:08:34
Wind? It can make wind? 00:08:37
Air always moves from a region of higher pressure to a region of lower pressure. 00:08:39
Wait, Dr. D, we haven't learned about pressure yet. What's that? 00:08:43
I guess I better slow down a little bit. 00:08:47
Air is made up of molecules like oxygen and nitrogen. 00:08:49
They're constantly in motion, traveling in straight lines until they bounce off of something. 00:08:52
So you mean right now we're being bombarded with molecules? 00:08:56
That's right. 00:08:59
Molecules bounce off of something, and they apply a force to that object. 00:09:03
This force creates what we call air pressure. 00:09:06
Let me show you an example. 00:09:09
These hemispheres have molecules bouncing off the outside. 00:09:10
I've taken most of the air out of the middle, 00:09:13
so there are very few molecules on the inside pushing out. 00:09:15
Here, try to pull it apart. 00:09:17
Wow, this is really hard. 00:09:19
That force you talked about is very real. 00:09:22
Now, if I let the air back into the middle, 00:09:25
we'll have molecules both pushing out and pushing in. 00:09:28
The pressure on the outside is the same as the pressure on the inside. 00:09:31
It shouldn't be a problem. 00:09:34
It's much easier now. 00:09:36
Let's try something else. 00:09:38
Put on your goggles and safety glasses. 00:09:40
I'm going to heat the air inside this can. 00:09:42
There's a little bit of water in it. 00:09:45
I'm going to turn the can upside down into the pan of water, 00:09:47
and the pressure in the can is going to drop very, very quickly, 00:09:51
and the higher pressure air on the outside is going to crush the can. 00:09:54
Watch this. 00:10:01
That's amazing! 00:10:04
Now, when I blow up this thing, 00:10:08
now, when I blow up this balloon, 00:10:10
I'll be increasing the density of the air inside. 00:10:12
That means the molecules will be more tightly packed. 00:10:14
This makes the pressure on the inside 00:10:17
greater than the pressure on the outside. 00:10:19
I knew that was going to happen. 00:10:28
So that's what you meant when you said 00:10:30
the air went from a region of higher pressure, like the balloon, 00:10:32
to a region of lower pressure, like this room. 00:10:35
Very good. 00:10:37
Now, suppose you're at the beach in the summer. 00:10:39
The sand is hot, and it warms the air above it. 00:10:41
The warmer air has a lower pressure than cooler air, 00:10:43
because it's less dense. 00:10:45
Now, the air above the ocean is cooler, 00:10:47
therefore it has a higher pressure than air above the sand. 00:10:49
What happens? 00:10:52
Well, I would think, just like the balloon, 00:10:54
that the wind would blow from the higher pressure air 00:10:56
across the ocean toward the lower pressure air on the beach. 00:10:58
Very good. That's what's called a sea breeze. 00:11:00
Here's an update from the Weather Channel. 00:11:02
Hey, look, there's an update from the Weather Channel. 00:11:04
...that we reported earlier has slightly strengthened 00:11:06
and become more organized, 00:11:08
with maximum sustained wind now at 30 mph. 00:11:10
This system has been upgraded 00:11:12
to a tropical depression. 00:11:14
It is currently located 00:11:16
at 15 degrees north 00:11:18
and 40 degrees west, 00:11:20
and it is moving northwest 00:11:22
at 20 mph. 00:11:24
Here's a globe. 00:11:26
Look, here are the Antilles Islands. 00:11:28
I think we should start tracking the storm. 00:11:30
Don't you? 00:11:32
Oh, I don't think so. It's far away. 00:11:34
Yes, we do. 00:11:36
The storm has turned into a tropical depression. 00:11:38
I don't want to miss the physics fair 00:11:40
or our trip to Florida. 00:11:42
Okay, where do we go from here? 00:11:44
Why don't you visit my friend, Dr. Lyons? 00:11:46
He's a meteorologist at the Weather Channel. 00:11:48
Dr. Lyons, I've seen him on TV before. 00:11:50
He's a hurricane expert. 00:11:52
We interrupt this broadcast 00:11:54
to bring you this breaking news. 00:11:56
We go now to the EPA Beach Cleanup Awards 00:11:58
and our reporter, I Am Listening. 00:12:00
Ted, we're about to hear 00:12:02
the winners of the Beach Cleanup Contest. 00:12:04
Let's listen in. 00:12:06
Um, we'll be back 00:12:12
with the announcement right after this. 00:12:14
So what's up? 00:12:16
Will the tropical depression become a hurricane? 00:12:18
Will the clouds help the detectives 00:12:20
predict next week's weather? 00:12:22
Is water vapor and condensation a clue? 00:12:24
Stay tuned for the next episode 00:12:26
of The Case of the Phenomenal Weather. 00:12:28
It's getting stormy in a treehouse. 00:12:34
Stick around 00:12:36
and help the treehouse detectives 00:12:38
answer the following questions. 00:12:40
Where is the eye 00:12:42
of the hurricane located? 00:12:44
What is the Coriolis effect? 00:12:46
How does LIDAR 00:12:48
tell the amount of water vapor 00:12:50
in the air? 00:12:52
Ladies and gentlemen, 00:12:54
we've just received word 00:12:56
that the award is about to be, 00:12:58
um, awarded. 00:13:00
We're sending you back live 00:13:02
to the EPA Beach Cleanup Awards. 00:13:04
And now, 00:13:06
the award 00:13:08
for 00:13:10
the Best Beach Cleanup 00:13:12
with 00:13:14
a record 00:13:16
16 tons 00:13:18
of trash. 00:13:20
The 00:13:22
Treehouse 00:13:24
Detectives. 00:13:26
There you have it, Ted. 00:13:28
There you have it, Ted. 00:13:30
Our own treehouse detectives 00:13:32
are going to SeaWorld. 00:13:34
Great job, kids. 00:13:36
I can't believe we won. 00:13:38
And get to go to SeaWorld in sunny Florida. 00:13:40
Now I'm really worried 00:13:42
about the tropical depression. 00:13:44
My grandparents live in Florida and they get a lot of hurricanes. 00:13:46
That's not good. 00:13:48
I don't want to miss out on the physics fair 00:13:50
or the SeaWorld trip. 00:13:52
We better do a lot more research on weather. 00:13:54
Yeah, especially hurricanes. 00:13:56
Over the past six hours, 00:13:58
the tropical depression has become 00:14:00
considerably better organized 00:14:02
and has strengthened into a tropical storm, 00:14:04
Ichabod. 00:14:06
The center of the storm is located near 00:14:08
a latitude of 13.3 north 00:14:10
and a longitude of 00:14:12
38.5 west. 00:14:14
Now Ichabod is moving toward the northwest 00:14:16
at 20 miles per hour. 00:14:18
It has maximum sustained wind 00:14:20
at 45 miles per hour. 00:14:22
Now some strengthening is expected 00:14:24
for the next 24 hours 00:14:26
and Ichabod could become a hurricane 00:14:28
in a day or two. 00:14:30
We will continue to closely watch this storm 00:14:32
from the Weather Channel. 00:14:34
I'm meteorologist Lisa Moser. 00:14:36
What? Did she say hurricane? 00:14:38
We're over here. 00:14:40
We had better start plotting the track 00:14:42
of tropical storm Ichabod. 00:14:44
This is getting serious. 00:14:46
Let's look at the map. 00:14:48
Remember, latitude lines run from east to west 00:14:50
and are divided at the equator into north and south. 00:14:52
13.4 degrees north. 00:14:54
That's above the equator. 00:14:56
And longitude lines run from north to south 00:14:58
and are divided by the promeridian into east and west. 00:15:00
38.5 degrees 00:15:02
west 00:15:04
is... 00:15:06
right there. 00:15:08
The storm is located where the two lines intersect. 00:15:10
But Sea World is located in Orlando, Florida. 00:15:12
Do you really think we need to worry about that? 00:15:14
Yes, I do, but I've got to go. 00:15:16
Later. 00:15:18
The variables in our problem are changing 00:15:20
and it could become a hurricane. 00:15:22
One variable that's changing is the storm's wind speeds. 00:15:24
I wonder what makes the wind speeds change. 00:15:26
It can be the sun 00:15:28
because storms have a lot of clouds 00:15:30
and rain. 00:15:32
I don't know. 00:15:34
Remember what Dr. D said about air pressure 00:15:36
and how wind is created? 00:15:38
I think we need to learn more about hurricanes. 00:15:40
We saw in the weather update 00:15:42
that the storm in the Atlantic Ocean 00:15:44
is now tropical depression. 00:15:46
We're afraid that it's going to affect 00:15:48
the Atlantic Ocean and the Tampa, 00:15:50
so we need to know how does a storm grow 00:15:52
and become a hurricane? 00:15:54
First you need to know a little bit about 00:15:56
pressure systems and how they form on Earth. 00:15:58
We learned about air pressure from Dr. D. 00:16:00
Is this the same thing? 00:16:02
There are two types of air pressure systems, 00:16:04
high and low. 00:16:06
The uneven distribution of the Earth's surface 00:16:08
causes them to form. 00:16:10
So you mean that's why it's hotter at the equator 00:16:12
than at the north and south poles? 00:16:14
Exactly. 00:16:16
These local temperature variations 00:16:18
cause air to rise in some areas 00:16:20
and to sink in other areas. 00:16:22
This rising and sinking motion 00:16:24
causes high and low pressure areas in the atmosphere. 00:16:26
What do high and low pressure systems 00:16:28
have to do with the tropical storm? 00:16:30
We have regions in the tropics 00:16:32
that are warmer and cooler than other regions. 00:16:34
Low pressure forms in the warm regions 00:16:36
and once they form they move from east to west. 00:16:38
I remember we learned 00:16:40
in the case of the mysterious red light 00:16:42
that winds in the tropics are called trade winds. 00:16:44
Trade winds? 00:16:47
These winds move from the east to the west. 00:16:49
Is that why they move in a westerly direction? 00:16:51
Yes, and as low pressure areas 00:16:53
move over the warm tropical oceans 00:16:55
they gather heat and moisture from the ocean 00:16:57
and cause thunderstorms. 00:16:59
The rain and the thunderstorms 00:17:01
warms the atmospheric air column 00:17:03
that causes the surface pressure to lower 00:17:05
thus strengthening the low pressure area. 00:17:07
So as the warm air rises 00:17:09
the pressure in the system gets cooler? 00:17:11
Something like that. 00:17:13
We take away air from the low pressure areas 00:17:15
and deposit them in the high pressure areas 00:17:17
and we end up with 00:17:19
very small but intense low pressure areas 00:17:21
and very weak but large 00:17:23
high pressure areas. 00:17:25
And what's the third way? 00:17:27
That happens when a hurricane forms an eye. 00:17:29
An eye? I know he doesn't mean a real eye. 00:17:31
No. 00:17:33
No, it's the 00:17:35
center of the hurricane 00:17:37
where there is no cloud. 00:17:39
Air is sinking near the center of the hurricane 00:17:41
and it warms up dramatically. 00:17:43
That warming causes the hurricane to intensify 00:17:45
rather dramatically. 00:17:47
Dr. V told us that wind is formed 00:17:49
when air moves from an area of high pressure 00:17:51
to an area of low pressure. 00:17:53
Do the winds of a hurricane increase as the pressure drops? 00:17:55
Yes, and the winds typically increase 00:17:57
as you move toward the eye or the center of the hurricane. 00:17:59
In strong hurricanes 00:18:01
the winds can vary rather dramatically. 00:18:03
About 20 mph on the outskirts of the hurricane 00:18:05
to more than 150 mph 00:18:07
near the center 00:18:09
of the eye wall of a hurricane. 00:18:11
Is the wind the fastest in the eye? 00:18:13
Actually, that's a common misconception. 00:18:15
It isn't. 00:18:17
The winds are strongest just outside the eye 00:18:19
and decrease rather dramatically 00:18:21
toward the circulation center 00:18:23
where they're oftentimes light and variable. 00:18:25
Sounds like a place to be in a hurricane. 00:18:27
Is there a particular time of year hurricanes are more likely to form? 00:18:29
That's a great question. 00:18:31
And in the northern hemisphere 00:18:33
it's June through November 00:18:35
when the sea surface temperatures are warmest 00:18:37
to hottest. 00:18:39
It's ideal for hurricane formation. 00:18:41
You've given us a lot to think about. 00:18:43
You're welcome. I'm glad I could help. 00:18:45
Be sure to watch the Weather Channel 00:18:47
for all the tropical storm and hurricane advisories and updates. 00:18:49
You also might want to visit the NASA 00:18:51
Y-Files website's research rack 00:18:53
and check out the link to the Weather Channel. 00:18:55
We will. Thanks. 00:18:57
Goodbye. 00:18:59
Dr. D said he was going to meet us 00:19:03
here at MOSI. 00:19:05
Look. There he is. 00:19:07
Riding a bicycle in a tightrope. 00:19:09
How is he doing that? 00:19:11
Hey, Dr. D. 00:19:13
How do you keep from falling? 00:19:15
The laws of physics make it impossible 00:19:17
for me to fall. 00:19:19
The huge counterweight below makes all the difference. 00:19:21
Are you sure you can trust those laws 00:19:23
all the time? 00:19:25
Don't worry about me. 00:19:27
I'll meet you in the hurricane room as soon as I get off the bicycle. 00:19:29
I've never been in a hurricane before. 00:19:37
Are you sure this is safe? 00:19:39
Of course it's safe. 00:19:41
In here, we'll feel one of the most tremendous 00:19:43
forces of nature. 00:19:45
It will only be a minimal hurricane, 00:19:47
but at 74 miles per hour, 00:19:49
it'll still be quite an experience. 00:19:51
Here we go. 00:19:53
Wow. 00:20:07
That was really amazing. 00:20:09
Are you sure that was just a minimal hurricane? 00:20:11
You bet. 00:20:13
Now, it's estimated that a really major hurricane 00:20:15
with 148 mile-an-hour winds 00:20:17
or twice what you just experienced 00:20:19
can produce 250 times 00:20:21
the property damage of a minimal hurricane. 00:20:23
Wow. That's a lot of energy. 00:20:25
Dr. Lyons told us 00:20:27
the sun evaporates water 00:20:29
and provides energy for the hurricane. 00:20:31
Yes, and the energy is given to the hurricane 00:20:33
when the evaporated water condenses into raindrops. 00:20:35
It turns out 00:20:37
if you condense just one liter of water, 00:20:39
it will give up enough energy 00:20:41
to power a 60-watt light bulb 00:20:43
for 11 hours. 00:20:45
But an average hurricane will condense 00:20:47
20 trillion liters of water in a day. 00:20:49
That's a 20 followed by 12 zeros. 00:20:51
Wow. 00:20:53
That's way too big a number for me to comprehend. 00:20:55
That's as much energy 00:20:57
as all the world's electrical generating plants 00:20:59
produce in 200 days. 00:21:01
Wow. Now I'm really impressed. 00:21:03
Hurricanes have a lot of energy. 00:21:05
Let me show you something else about hurricanes. 00:21:07
It's pretty interesting. 00:21:09
It turns out that hurricanes in the northern hemisphere 00:21:11
all have a counterclockwise rotation. 00:21:13
All of them? 00:21:15
That's right. It's because the hurricane 00:21:17
is a low-pressure region. 00:21:19
When the air in the higher-pressure region around it 00:21:21
rushes in, it gets bent to the right 00:21:23
because of the rotation of the Earth. 00:21:25
This causes the counterclockwise rotation of the hurricane. 00:21:27
I don't get it. 00:21:29
Does the rotation of the Earth make any difference? 00:21:31
We just happen to have a very interesting device 00:21:33
here at the museum to help us understand how it works. 00:21:35
Each of you sit on opposite ends of the board 00:21:37
and I'll give you a spin. 00:21:39
Hope you don't get too dizzy. 00:21:41
Now Bianca, toss the ball over to Katherine. 00:21:47
It didn't even come close. 00:21:52
Try it again. 00:21:54
It curved to the right after I threw it. 00:21:56
The ball appeared to curve for the same reasons 00:21:58
the winds are bent to the right 00:22:00
when they rush in toward the center of a hurricane. 00:22:02
It's called the Coriolis effect 00:22:04
and it exists in any rotating system. 00:22:06
I see the ball traveling in a straight line, 00:22:08
but as you see it on the rotating board, 00:22:10
it really is curving. 00:22:12
Wow, this is so much fun. 00:22:14
I could sit on this all day. 00:22:16
Not me. I'm getting dizzy. 00:22:18
I need to get off this thing. 00:22:20
If you like conducting experiments, 00:22:22
you need to check out Dr. D's lab 00:22:24
on the NASA Wi-Fi's website. 00:22:26
That was so amazing. 00:22:28
I can't believe I was actually 00:22:30
in hurricane force winds. 00:22:32
Sounds like it was really a blast. 00:22:34
It was a blast, a blast of wind at 74 miles per hour. 00:22:36
But the good thing is it ended. 00:22:38
I would never want to be in a real hurricane. 00:22:40
Me either. 00:22:42
I'm Lisa Moser from the Weather Channel 00:22:44
with an important update on Ichabod. 00:22:46
In the last 24 hours, 00:22:48
the storm has strengthened 00:22:50
and is now at maximum sustained wind 00:22:52
of 79 miles per hour, 00:22:54
making it a Category 1 hurricane. 00:22:56
Based on satellite information, 00:22:58
it is continuing 00:23:00
in a northwest direction 00:23:02
at 20 miles per hour. 00:23:04
The center of the storm 00:23:06
is located near a latitude 00:23:08
of 15.3 north 00:23:10
and a longitude of 43.9 west. 00:23:12
In a few hours, 00:23:14
the U.S. Air Force 00:23:16
is expected to send in 00:23:18
reconnaissance aircraft 00:23:20
to get an update on Ichabod. 00:23:22
Meanwhile, the National Hurricane Center 00:23:24
has issued a hurricane watch 00:23:26
for the islands of the Lesser Antilles. 00:23:28
Stay tuned for updates 00:23:30
as we continue to follow this storm. 00:23:32
Oh no, it's now a hurricane. 00:23:34
We better get busy 00:23:36
and figure this problem out. 00:23:38
I wonder what Category 1 means. 00:23:40
Do you know what it is? 00:23:42
I've got it on the map. 00:23:44
It says latitude 15.3 north 00:23:46
and a longitude of 43.9 west. 00:23:48
I think we need to go 00:23:50
to the problem board. 00:23:52
We know that the Tropical Depression 00:23:54
is now a hurricane. 00:23:56
And we know about clouds 00:23:58
and its storms are low pressure systems. 00:24:00
And we know that hurricanes 00:24:02
usually move from east to west 00:24:04
and they get bigger with higher winds 00:24:06
when they move over warm waters. 00:24:08
And we know that water vapor 00:24:10
feeds this storm. 00:24:12
Do you think we need a hypothesis? 00:24:14
With what we know, 00:24:16
I think our hypothesis should be 00:24:18
if the storm continues to increase in strength, 00:24:20
then it will hit Florida. 00:24:22
It sounds like we need to know 00:24:24
if the storm is going to get any stronger. 00:24:26
I read about Dr. Brow. 00:24:28
He's with NASA Langley Research Center 00:24:30
using some LiDAR to find 00:24:32
how much water vapor is in a hurricane. 00:24:34
That's a good idea, 00:24:36
since we know that water vapor 00:24:38
feeds a storm. 00:24:40
Wait, I found hurricane hunters 00:24:42
Let's break into small groups 00:24:44
and do some investigating. 00:24:46
Don't forget your get up and go sheet. 00:24:48
We can write down everything and then share it. 00:24:50
Hello, Dr. Brow? 00:24:52
Oh, hello. 00:24:54
You must be one of the treehouse detectives. 00:24:56
I just spoke with Dr. D on the phone 00:24:58
and he said you were coming over. 00:25:00
We're trying to figure out how scientists 00:25:02
can predict if a tropical storm will get bigger or smaller. 00:25:04
I definitely can help you with that. 00:25:06
We learned about LiDAR before, 00:25:08
but we could use a review. 00:25:10
Can you help us? 00:25:12
Certainly. LiDAR is an acronym 00:25:14
that stands for Light Detection and Ranging. 00:25:16
It's a pulsating instrument 00:25:18
that is used to probe the atmosphere. 00:25:20
Let's take a look now at how laser light 00:25:22
scatters in the atmosphere. 00:25:24
You've seen a laser pointer before. 00:25:26
If you would pass the beam from the pointer 00:25:28
through this plume from the vaporizer, 00:25:30
you'll see the scattering from the small particles 00:25:32
just like a LiDAR sees in the atmosphere. 00:25:34
Wow, this is neat. 00:25:36
And if you would imagine 00:25:38
using a pulsed laser, 00:25:40
we could see where the scattering is 00:25:42
and how much is there, 00:25:44
much like a laser radar. 00:25:46
But how do you measure water vapor with a LiDAR? 00:25:48
Come on, let me show you. 00:25:50
Take a look at these two laser beams. 00:25:54
Now you can slide the container 00:25:56
of colored water into the two beams 00:25:58
and see what happens. 00:26:00
The green laser light almost disappears. 00:26:04
Exactly. 00:26:06
By comparing the intensity 00:26:08
and how much changes in the green light, 00:26:10
we can calculate how much dye is in the cell. 00:26:12
So you mean you can 00:26:14
detect the amount of water vapor 00:26:16
by comparing how two laser lights change 00:26:18
when water vapor is present? 00:26:20
Exactly. Let's go see a LiDAR 00:26:22
that's flown around a hurricane. 00:26:24
This LiDAR system is called LASE. 00:26:29
LASE stands for 00:26:31
LiDAR Atmospheric Sensing Experiment 00:26:33
and it was designed to go 00:26:35
into a very high altitude airplane. 00:26:37
When LASE is flown on an airplane 00:26:39
around a hurricane, we can make 00:26:41
measurements of how much water vapor 00:26:43
is flowing into the hurricane. 00:26:45
We learned that water vapor feeds the storm. 00:26:47
You're right. Water vapor is the 00:26:49
primary energy source that drives the hurricane. 00:26:51
Why would NASA want to fly 00:26:53
around hurricanes? 00:26:55
The information we gather with our experiments 00:26:57
should help us to better predict hurricane behavior. 00:26:59
And we hope to develop 00:27:01
very small LiDAR systems 00:27:03
available on unmanned aerial vehicles 00:27:05
or UAVs, which are small model aircraft. 00:27:07
Why would you want to put 00:27:09
LiDAR on such small planes? 00:27:11
Well, a UAV can fly around 00:27:13
a hurricane for several days 00:27:15
and get the information we need 00:27:17
to help better predict what the hurricane 00:27:19
will do. In the future, 00:27:21
we hope to develop a LiDAR system to go 00:27:23
into space to do the same thing. 00:27:25
Wow. That would be really awesome. 00:27:27
Thanks, Dr. Brower. You've been a big help. 00:27:29
This is the plane that hurricane hunters 00:27:31
use to chase storms. 00:27:33
Let's check it out. 00:27:35
Hi. You must be one of the treehouse detectives. 00:27:37
Yes, I'm RJ. 00:27:39
We're going on a mission right now. You want to go? 00:27:41
You bet. 00:27:43
Alright. I'll get you in a flight suit and I'll let you talk to our 00:27:45
pilot, Captain Ford. Let's go. 00:27:47
Hello, RJ. 00:27:51
How's our newest hurricane hunter today? 00:27:53
I'm fine. But why are you guys called the hurricane hunters? 00:27:55
Our mission is weather reconnaissance. 00:27:57
But our most famous type of mission 00:27:59
is to fly into hurricanes. 00:28:01
Why do you need to fly into a hurricane? 00:28:03
We fly into hurricanes to gather data 00:28:05
which will help determine the location and intensity 00:28:07
of the hurricane. If the storm is well 00:28:09
developed, we can locate the center 00:28:11
and the rain bands using satellites. 00:28:13
If the hurricane is less developed, 00:28:15
then it's harder to locate the center of the storm 00:28:17
and it becomes more of a hunt. 00:28:19
Are we going to fly through a hurricane? 00:28:21
Not this time. But you better get strapped in. 00:28:23
We're almost ready to go. 00:28:25
Captain Gibson, 00:28:29
what's your job on this mission? 00:28:31
I'm a meteorologist or what they would call 00:28:33
an aerial reconnaissance weather officer. 00:28:35
What we do is collect 00:28:37
all the data about the storm 00:28:39
such as where it's located and how strong 00:28:41
it is. We take all the information 00:28:43
and we send it via satellite to the National Hurricane Center 00:28:45
where they can start working on their forecasts. 00:28:47
How does the data you collect 00:28:49
help meteorologists? 00:28:51
The National Hurricane Center sends us out 00:28:53
to gather all the data. 00:28:55
You see, RJ, when we fly into a storm 00:28:57
system, not only do we have weather sensors 00:28:59
dotting the aircraft all the way around, 00:29:01
we also release 00:29:03
sensors called drop sonnets. 00:29:05
What's happening? 00:29:09
It looks like we found our tropical disturbance. 00:29:11
Not quite a tropical storm yet, but we'll have to 00:29:13
keep our eye on it. It does decrease 00:29:15
in intensity and perhaps become a hurricane 00:29:17
a little later on this week. That's so cool. 00:29:19
What other types of storms are there? 00:29:21
RJ, there are four main types of storms. 00:29:23
First, you start out with a tropical wave. 00:29:25
That's just an area below pressure. 00:29:27
It just causes a lot of rainfall 00:29:29
and doesn't have high wind speeds. 00:29:31
But as the storm intensifies, it becomes 00:29:33
a tropical depression. Those have wind 00:29:35
speeds up to 38 miles per hour. 00:29:37
It doesn't quite have a closed circulation 00:29:39
of winds. Once it reaches 00:29:41
39 miles per hour, all the way up to 00:29:43
73 miles per hour, 00:29:45
it becomes a tropical storm. 00:29:47
It does have a closed circulation of air. 00:29:49
When does a tropical storm become a hurricane? 00:29:51
A hurricane begins when the winds 00:29:54
reach 74 miles per hour. 00:29:56
There's five different categories of hurricanes. 00:29:58
Category 1 starts at 74 00:30:00
and goes up to 95 miles per hour. 00:30:02
Then you have Category 2. 00:30:04
That goes from 96 miles per hour 00:30:06
to 110 miles per hour. 00:30:08
Then Category 3, 111 00:30:10
to 130 miles per hour. 00:30:12
Wow, that's a powerful storm. 00:30:14
Have you had very many 00:30:16
Category 3 hurricanes? 00:30:18
Yes, we've had several that reached Category 4 00:30:20
hurricanes. That's when the winds get 00:30:22
from 131 to 155 00:30:24
miles per hour. Has there ever been 00:30:26
a Category 5 hurricane? 00:30:28
Yes, but only two have ever made landfall in the last 00:30:30
century. It requires the winds 00:30:32
to be above 155 miles 00:30:34
per hour, and the conditions have to be 00:30:36
just right for that to happen. 00:30:38
Well, I'm glad there aren't very many Category 00:30:40
5 hurricanes. Me too. 00:30:42
Do you guys have a bathroom on the plane? 00:30:44
Yes, we do. 00:30:46
It's in the back. 00:30:48
RJ, 00:30:52
did you find it yet? 00:30:54
I think I'll wait. 00:30:56
Thanks a lot. 00:30:58
This was awesome. Anything for the 00:31:00
Treehouse Detectives. 00:31:02
Wow, 00:31:04
I actually flew with the Air Force Reserve 00:31:06
Hurricane Hunters. Wait till the 00:31:08
guys read my get up and go sheet on this one. 00:31:10
So what's up? 00:31:14
Will Hurricane Ichabod continue to receive 00:31:16
water vapor? Will it become a 00:31:18
Category 2 hurricane? 00:31:20
How will its strengthening affect the people living along 00:31:22
the coast? Don't miss the next 00:31:24
chapter of The Case of the Phenomenal Weather. 00:31:26
The Treehouse Detectives 00:31:34
are getting warmer. 00:31:36
Keep your eyes open and 00:31:38
answer the following questions. 00:31:40
What is probability? 00:31:42
What force 00:31:44
holds satellites in orbit 00:31:46
around the Earth? 00:31:48
How will GIFs help meteorologists 00:31:50
predict storms earlier? 00:31:52
The center 00:31:54
of the storm is located near a 00:31:56
latitude of 18 north 00:31:58
and a longitude of 53 west. 00:32:00
It now has maximum 00:32:02
sustained wind at 108 00:32:04
miles per hour. Ichabod is 00:32:06
now a strong Category 2 00:32:08
hurricane. The National Hurricane 00:32:10
Center has issued a hurricane 00:32:12
warning now for the northernmost 00:32:14
islands of the Western Antilles and 00:32:16
the Virgin Islands. And a hurricane 00:32:18
watch for the islands of the Bahamas. 00:32:20
Wow, the hurricane is moving closer 00:32:22
to Florida. I think our hypothesis 00:32:24
is correct. It's getting stronger and 00:32:26
closer. Look, I just put the coordinates on the map. 00:32:28
Guys, the hurricane is still 00:32:30
a long way away. I don't think we should jump 00:32:32
to any conclusions. 00:32:34
And we learned from the hurricane hunters that a Category 2 00:32:36
storm can do some major damage. 00:32:38
I wonder if anyone in the NASA Y-Files 00:32:40
Kids Club has experienced a hurricane. 00:32:42
I don't know, but I think it would be good 00:32:44
if we could speak to someone who has. 00:32:46
I already asked some of our club members. 00:32:48
In this hurricane book, it says that 00:32:50
wind isn't the only thing that causes damage 00:32:52
during a hurricane. The storm surge 00:32:54
and rain can also cause flooding. 00:32:56
Storm surge? What's that? 00:32:58
When the wind pushes seawater 00:33:00
towards the shore, the water piles 00:33:02
up, creating a wall of water that can be up to 00:33:04
24 feet high. It also says 00:33:06
that tornadoes can even occur during a hurricane. 00:33:08
Tornadoes? 00:33:10
Like in The Wizard of Oz? 00:33:12
We're not in Kansas. 00:33:14
And I'm not Dorothy. 00:33:16
You don't have to be in Kansas to have tornadoes. 00:33:18
Even though Kansas is in Tornado Alley. 00:33:20
Hey look guys, I'm getting an email 00:33:22
back from Jonathan Juarez in Miami. 00:33:24
His home was destroyed by Hurricane Andrew. 00:33:26
I'm sure he has a lot of information. 00:33:28
Let's contact him. 00:33:30
Hi, my name is Jonathan Juarez 00:33:36
and I'm here with my cousin Jimena Valdez 00:33:38
and we are both Hurricane Andrew survivors. 00:33:40
Hi Jonathan, will you tell us 00:33:42
what it was like to go through Hurricane Andrew? 00:33:44
Yes, I was 5 years old 00:33:46
at the time. I was getting ready for my first day 00:33:48
of kindergarten when Hurricane Andrew 00:33:50
hit my neighborhood outside of Miami. 00:33:52
I can't believe you survived a hurricane. 00:33:54
Did you hide in your house or run? 00:33:56
Well, our family stayed inside the bathroom 00:33:58
since it was the only room in the house 00:34:00
without any windows. It seemed like 00:34:02
a good idea, but we didn't take any shoes 00:34:04
with us. So after the storm, we 00:34:06
went over to Jonathan's house 00:34:08
barefoot because all our shoes had been 00:34:10
blown away during the hurricane. 00:34:12
I don't remember that much about 00:34:14
what happened during the storm 00:34:16
because it's pretty amazing, but 00:34:18
I fell asleep for 00:34:20
most of the storm and when I woke up 00:34:22
it was over. 00:34:24
You fell asleep? 00:34:26
Yeah, but when I woke up I noticed that 00:34:28
the whole top floor of my house 00:34:30
was ripped off. Do you still live in the same 00:34:32
neighborhood? No, but the neighborhood 00:34:34
looks pretty normal now. It doesn't look 00:34:36
anything like it did ten years ago 00:34:38
and there's no way to describe the damage. 00:34:40
My advice would be to stay 00:34:42
in the safest place of your house, preferably 00:34:44
away from windows, and 00:34:46
put up plywood shutters if you 00:34:48
don't have the steel ones. Also, 00:34:50
remember to bring a change of clothes and an 00:34:52
extra pair of shoes. 00:34:54
Wow, you would never think a hurricane 00:34:56
could destroy your entire house. 00:34:58
Yeah, your house and everything in it. 00:35:00
That'd be just my luck to go 00:35:02
to Florida and get stuck in a hurricane. 00:35:04
I just finished entering our notes that we took 00:35:06
at MOSI from our problem log. 00:35:08
You can download your own problem log from the NASA 00:35:10
Wi-Fi's website. 00:35:12
We have a lot of new information. I think we need 00:35:14
to go to the problem board. 00:35:16
We know the tropical depression is now a hurricane. 00:35:18
We know that hurricanes 00:35:20
generally move from the east to the west. 00:35:22
And we know that water vapor is the 00:35:24
primary source of energy that drives a hurricane. 00:35:26
What we need to know is more 00:35:28
about the probability that the hurricane will 00:35:30
actually hit Florida. 00:35:32
Where should we go? Let's go talk to Dr. D. 00:35:34
I'm sure he can help us out. 00:35:36
Hi, Dr. D. 00:35:40
What are you doing? 00:35:42
Working on a tornado box. Your work on hurricanes 00:35:44
inspired me to start this project. 00:35:46
Are tornadoes just mini hurricanes on land? 00:35:48
Hey, guys. Have we missed 00:35:50
anything? Just showing them my tornado box. 00:35:52
Oh, cool. 00:35:54
Tornadoes and hurricanes are different from each other, 00:35:56
but it turns out they're very similar in that 00:35:58
they're both low-pressure regions, 00:36:00
and they have counter-clockwise wind patterns. 00:36:02
They also both have tremendous energy. 00:36:04
I'm concerned if the hurricane is going to ruin 00:36:06
our fun. How can we predict 00:36:08
where it will hit land? 00:36:10
You've asked one of the biggest questions a meteorologist asked. 00:36:12
To find an answer to this question, they ask such 00:36:14
questions as, where has the hurricane 00:36:16
been? Are there high and low pressure 00:36:18
systems that affect the hurricane? 00:36:20
And what are the speed and directions of the steering winds? 00:36:22
Steering winds? 00:36:24
Yes, those are the winds that push the hurricane a lot. 00:36:26
That's a lot of variables. 00:36:28
Remember, with the scientific process, 00:36:30
we have to keep track of all the variables. 00:36:32
We're pretty good at making predictions. 00:36:34
Let's see. We have a number of 00:36:36
objects. I want you to pick them up one at a time 00:36:38
and see if you can tell which ones will float. 00:36:40
That's easy. 00:36:42
I think this apple will definitely float. 00:36:44
I played bobbing for apples before, and I remember 00:36:46
seeing the apples float in the bucket. 00:36:48
Yep, I was right. 00:36:52
You used your previous experience to make a prediction. 00:36:54
Hurricane forecasters also rely 00:36:56
upon their previous experiences. 00:36:58
They look upon what previous hurricanes 00:37:00
had in similar situations. 00:37:02
Okay, let's try this golf ball. 00:37:04
I think it will float. 00:37:06
Oops, it sank. 00:37:08
Well, try this bowling ball. 00:37:10
I think you made this one too easy. 00:37:12
It will definitely sink, because it's too heavy. 00:37:14
Alright, let's see. 00:37:16
Wow, two in a row wrong. 00:37:20
I guess you can't tell just 00:37:22
whether something will sink or float. 00:37:24
What are some other ways we can tell if something will sink or float? 00:37:26
You need to know both the mass and the volume of each object. 00:37:28
If the mass of the object 00:37:30
expressed in grams is greater 00:37:32
than the volume expressed in milliliters, 00:37:34
it will sink, because it's denser 00:37:36
than water. The problem with hurricanes 00:37:38
is there are so many variables, it's a very complex 00:37:40
problem. And even if we knew 00:37:42
all the variables precisely, we're not 00:37:44
quite sure how they all fit together. 00:37:46
So, what do they do? 00:37:48
Instead of being able to make an exact prediction, 00:37:50
all weather forecasters can do 00:37:52
is to talk about probabilities. 00:37:54
We need to learn more about probabilities. 00:37:56
Let's look at an example. 00:37:58
When we flip this coin, 00:38:02
will it come up heads or tails? 00:38:04
We don't know. 00:38:06
That's right, because it's a random event. 00:38:08
But what's the likelihood that it'll come up heads? 00:38:10
I guess it'll come up heads about half the time. 00:38:12
That's right. And probability says 00:38:14
it'll come up heads about 50% of the time. 00:38:16
Let's try it. 00:38:18
I get heads, 00:38:20
tails, 00:38:22
tails, 00:38:24
and another tails. 00:38:26
Wait, it didn't come up heads half the time. 00:38:28
Well, that's alright, because probability says 00:38:30
if we do a lot of trials, 00:38:32
it'll abruptly be 50%. 00:38:34
Let's keep trying. 00:38:36
Got heads, 00:38:38
another heads, 00:38:40
a tails, 00:38:42
and heads. 00:38:44
Yes, it's looking better. I think I remember the weatherman 00:38:46
saying last week that there was a 60% probability 00:38:48
of rain. Does that mean 00:38:50
it's going to rain 60% of the day? 00:38:52
No, I think that means that if there are 10 similar 00:38:54
days, then it would rain on 6 of them. 00:38:56
I think you're catching on. 00:38:58
Hurricane forecast will give the most probable 00:39:00
landfall time and location. 00:39:02
They also want to predict the strength of the hurricane. 00:39:04
The more confident they are, 00:39:06
the higher the percentage of the probability. 00:39:08
But can't some of the variables change 00:39:10
after they make a prediction? 00:39:12
You bet. That's the problem. For example, 00:39:14
if a hurricane's steering winds slow down 00:39:16
and the hurricane stalls over very warm water, 00:39:18
it might not only change the landfall 00:39:20
time, but it might also allow the hurricane 00:39:22
to gain its strength. 00:39:24
So how do they get the exact measurements? 00:39:26
And how many variables do they have to measure? 00:39:28
Hold on now. Weather satellites are a great 00:39:30
tool for making predictions and tracking hurricanes. 00:39:32
Why don't you talk to Nita Rapp 00:39:34
at NASA Langley Research Center? 00:39:36
Just get an email from her. She's right now at the 00:39:38
Air and Space Center in Hampton, Virginia. 00:39:40
I don't live too far from there. I'll ask my mom to take me. 00:39:42
Hi, Ms. Rapp. 00:39:44
Thanks for meeting us. Sure. 00:39:46
What's the problem? We need to learn more about 00:39:48
collecting weather data. Yeah. 00:39:50
We're worried about Hurricane Igobot in the Atlantic Ocean. 00:39:52
And we want to make sure it doesn't 00:39:54
ruin our trip to Florida. Well, that wouldn't be good. 00:39:56
Weather data is collected in 00:39:58
many ways, but one way is by a weather satellite. 00:40:00
What is a weather satellite? 00:40:02
A weather satellite is a man-made object 00:40:04
that's put into orbit around a planet 00:40:06
to help gather data all around the globe. 00:40:08
It helps improve weather forecasting. 00:40:10
That's just what we need. 00:40:12
How do satellites get into space? 00:40:14
They're launched into orbit by rockets 00:40:16
and sometimes even the shuttle takes them up. 00:40:18
Okay, but how do they stay up there? 00:40:20
Why don't they fall back down to Earth? 00:40:22
Satellites are held in orbit by a force called gravity. 00:40:24
Here, let's do an experiment. 00:40:26
But first, I need a ball. 00:40:28
Thanks. 00:40:30
Now, pretend that you're the Earth 00:40:32
and the ball is a satellite 00:40:34
and swing it around your head. 00:40:36
This is cool, 00:40:38
but satellites don't have strings 00:40:40
attached to them, do they? 00:40:42
No. Gravity is the string 00:40:44
that holds a satellite in orbit. 00:40:46
By swinging the ball, you are giving it 00:40:48
forward motion, or momentum, 00:40:50
just like the rockets do for the satellites. 00:40:52
If the string weren't attached to it, 00:40:54
it would fly off in one direction. 00:40:56
Oh, I get it. So if we didn't have gravity, 00:40:58
the satellites would fly off into space. 00:41:00
Very good. And when the momentum 00:41:02
and the gravity are equal, 00:41:04
the satellite stays in its orbit. 00:41:06
I saw on the NASA Langley website 00:41:08
that they use geostationary satellites. 00:41:10
But what does geostationary mean? 00:41:12
Well, if you break the word apart, 00:41:14
you have geo, which means Earth, 00:41:16
and stationary, which means fixed at a point. 00:41:18
So a geostationary satellite 00:41:20
orbits at a speed that matches 00:41:22
the speed of the Earth's rotation, 00:41:24
so it always stays over the same latitude and longitude. 00:41:26
Are there other kinds of satellites? 00:41:28
Yes, there are several types 00:41:30
of weather satellites, but the most common 00:41:32
besides geostationary are the polar orbiting satellites. 00:41:34
These constantly circle the Earth 00:41:36
in an almost north-south orbit. 00:41:38
Why are polar orbiting satellites important? 00:41:40
Because they cover the entire globe, 00:41:42
unlike geostationary satellites 00:41:44
that only see the same portion of the globe all the time. 00:41:46
How many weather satellites are there? 00:41:48
Well, counting only the geostationary 00:41:50
and polar orbiting satellites, 00:41:52
there are about 18. 00:41:54
However, there are about 00:41:56
2,671 satellites 00:41:58
of all different types in space. 00:42:00
Wow, that's a lot of satellites. 00:42:03
They must be important. 00:42:05
Yes, they are, and especially weather satellites. 00:42:07
They help us monitor storm development 00:42:09
and track the movement of storms. 00:42:11
Are they just used for hurricanes and tropical storms? 00:42:13
No, they're also used 00:42:15
to help our local meteorologists forecast our weather. 00:42:17
This helps them issue warnings 00:42:19
for thunderstorms and hurricanes. 00:42:21
We can now see that meteorologists 00:42:23
have a lot of help collecting data from satellites. 00:42:25
If you want to learn about a really 00:42:27
cool satellite that will be launched in the future, 00:42:29
you need to go see Bill Smith. 00:42:31
That sounds like our man. 00:42:33
Thanks for your help. 00:42:35
But first, before we go, 00:42:37
let's go check out another hurricane room. 00:42:39
Bye. 00:42:41
Hi, Dr. Smith. 00:42:47
I'm Kaylee, one of the triage detectives. 00:42:49
We've heard that you've developed 00:42:51
a new satellite that will be able 00:42:53
to predict weather more accurately. 00:42:55
That's right. It's called the GIFS. 00:42:57
Is the satellite present? 00:42:59
No. GIFS is an acronym that stands 00:43:01
for Geostationary Imaging Foyer Transform Spectrometer. 00:43:03
Or more simply, 00:43:05
GIFS is a digital camera 00:43:07
placed on a satellite 00:43:09
high above the Earth. 00:43:11
Why is it important that the satellite remain in place? 00:43:13
Oh, because if the camera is in a geostationary position, 00:43:15
we can make 3-D movies 00:43:17
of the atmosphere. 00:43:19
Do you need to wear 3-D glasses 00:43:21
to see them? 00:43:23
No, it's not that kind of a movie. 00:43:25
Why is 3-D important? 00:43:27
Most geostationary satellites provide 00:43:29
2-dimensional movies, 00:43:31
but the GIFS adds a third dimension, 00:43:33
altitude. 00:43:35
So with the GIFS, we can tell the height of the storm 00:43:37
as well as its geographical location. 00:43:39
The 3-dimensional data from GIFS, 00:43:41
such as temperature, water vapor, and winds, 00:43:43
will be fed into computer models, 00:43:45
and this will greatly improve 00:43:47
forecasts of weather, climate, and air pollution. 00:43:49
Will GIFS help meteorologists 00:43:51
predict storms even sooner? 00:43:53
GIFS, unlike any other satellite camera, 00:43:55
can observe the upward spiraling 00:43:57
motion of air molecules 00:43:59
and alert meteorologists that storms 00:44:01
will form long before they're observed 00:44:03
on radar or in other satellite pictures. 00:44:05
So we would know not to go 00:44:07
to Florida way before the storm 00:44:09
even gets there. 00:44:11
How will GIFS predict the path of a hurricane? 00:44:13
GIFS senses the motion 00:44:15
of air molecules and clouds 00:44:17
at different altitudes in the atmosphere. 00:44:19
It provides a measure of the 00:44:21
atmospheric winds that steer the storm's movement. 00:44:23
In other words, the winds 00:44:25
tell us where the storm will go. 00:44:27
Given the speed and the velocity 00:44:29
of the wind, we can predict 00:44:31
the future position of a hurricane. 00:44:33
We talked to a family in Miami 00:44:35
whose house was destroyed by Hurricane Andrew. 00:44:37
I wonder if GIFS would have helped them. 00:44:39
Most definitely. 00:44:41
The earlier we can warn people, the more time they have 00:44:43
to prepare for the storm. 00:44:45
This will result in less property damage 00:44:47
and fewer deaths. 00:44:49
GIFS can even help save millions of dollars. 00:44:51
Wow! How can it do that? 00:44:53
Well, for each mile of coastline 00:44:55
that is warned of a hurricane coming ashore, 00:44:57
a million dollars is spent in preparing 00:44:59
for the hurricane's landfall. 00:45:01
So if you knew exactly where the hurricane 00:45:03
was going to hit, fewer people 00:45:05
would have to spend money preparing for it. 00:45:07
Right. The average error predicting 00:45:09
where landfall will occur 00:45:11
24 hours in advance 00:45:13
is 125 miles. 00:45:15
So if we were able to reduce that error 00:45:17
by, say, a small 10%, 00:45:19
well, how many miles would that be? 00:45:21
Well, 10% of 125 00:45:23
is 12.5 miles. 00:45:25
So that would be 00:45:27
12.5 million dollars. 00:45:29
That's correct. 00:45:31
We expect even much greater improvements with GIFS. 00:45:33
That's going to be awesome. 00:45:35
But I wish you had it right now 00:45:37
so we would know if the hurricane was going to be 00:45:39
anywhere near SeaWorld in Florida. 00:45:41
I'll let you know when it gets close, 00:45:43
but it won't be in the next couple of weeks. 00:45:45
Thanks, Dr. Smith. 00:45:47
You're welcome. 00:45:49
Bye. 00:45:51
So what's up? 00:45:53
Will satellites help the Treehouse Detectives 00:45:55
predict where the storm is heading? 00:45:57
Do you think there's a strong probability 00:45:59
that the storm will hit Florida? 00:46:01
Should the area be evacuated? 00:46:03
We'll be back for the conclusion 00:46:05
of The Case of the Phenomenal Weather. 00:46:07
The Treehouse Detectives 00:46:09
are close to cracking 00:46:11
the case of the phenomenal weather. 00:46:13
Let's answer these final questions. 00:46:15
How are hurricanes named? 00:46:19
What is the difference between 00:46:21
a hurricane watch and a hurricane warning? 00:46:23
How can past hurricanes 00:46:25
help to predict the track 00:46:27
of future hurricanes? 00:46:29
I'm just finishing up 00:46:33
fixing Jacob's roller coaster. 00:46:35
That's so cool. 00:46:37
Pretty soon we'll be learning the physics behind the coaster. 00:46:39
Yes, in just a few days we'll be enjoying 00:46:41
the new weather. 00:46:43
Thank goodness that hurricane isn't strengthening very fast. 00:46:45
Don't forget, we still have to worry 00:46:47
about our trip to Florida next week. 00:46:49
I'm reading this book on hurricanes. 00:46:51
And I think that if we learn something 00:46:53
about the past hurricanes, 00:46:55
then maybe we can do something 00:46:57
about the future ones. 00:46:59
That's a good idea. 00:47:01
Let's watch Dr. Tech's book. 00:47:03
He has a segment on the history of hurricanes. 00:47:05
Hello. 00:47:07
Did you know that it was not until 1953 00:47:09
that scientists like myself 00:47:11
even gave names to hurricanes? 00:47:13
Of course. 00:47:15
Back then it was 00:47:17
ladies first. 00:47:19
Now, the first tropical storm ever named 00:47:21
began with the letter A. 00:47:23
After that came the letter B 00:47:25
and then so on and so forth. 00:47:27
You get the idea. 00:47:29
In 1979, it was decided 00:47:31
to add men's names to the list. 00:47:33
Hello, my name is Bob. 00:47:35
I want a hurricane named after me. 00:47:37
In 1900, 00:47:39
the Great Galveston Hurricane 00:47:41
was the worst natural disaster 00:47:43
in U.S. history. 00:47:45
The hurricane pounded the island 00:47:47
with great force off the coast of Texas. 00:47:49
It killed many, many people. 00:47:51
It had wind forces 00:47:53
of 125 miles per hour, 00:47:55
much of what I'm going 00:47:57
to demonstrate right now. 00:47:59
Oh, well. 00:48:01
At any rate, 00:48:03
2,600 homes were devastated 00:48:05
and it destroyed 00:48:07
over three-quarters of the city. 00:48:09
On August 26, 1992, 00:48:13
Hurricane Andrew 00:48:15
hit south of Miami 00:48:17
with wind gusts of up to 00:48:19
195 miles per hour. 00:48:21
I need a fan that works. 00:48:23
Hurricane Andrew 00:48:27
cut a 25-mile-wide path 00:48:29
through the Everglades National Park. 00:48:31
And there's more. 00:48:33
A huge path of destruction. 00:48:35
62 people dead. 00:48:37
25,000 homes destroyed. 00:48:39
Another 100,000 00:48:41
damaged. 00:48:43
Well, be that as it may, 00:48:45
I will now demonstrate 00:48:47
the power of hurricanes! 00:48:49
Uh-oh. 00:48:51
What a very good idea. 00:49:01
This has been 00:49:05
The History of Hurricanes 00:49:07
with Dr. Textbook. 00:49:09
Scary. 00:49:11
See you, Dr. Textbook. 00:49:13
I'm glad we have lots 00:49:15
of satellites. 00:49:17
Isn't technology a wonderful thing? 00:49:19
But those are the hurricanes 00:49:21
from the past. 00:49:23
We still need to figure out 00:49:25
how to predict the probability 00:49:27
of the hurricane 00:49:29
that's coming to Florida. 00:49:31
Hi, I'm Ashandria. 00:49:33
And I'm Molly. 00:49:35
And we are both here from 00:49:37
Mrs. Shigley's 5th grade class 00:49:39
at Thompson Elementary School 00:49:41
in Vero Beach, Florida. 00:49:43
The hurricane game gives 00:49:45
our class the experience 00:49:47
of tracking a hurricane 00:49:49
and predicting its possible landfall. 00:49:51
How do you track hurricanes 00:49:53
in your game? 00:49:55
We use a tracking chart 00:49:57
that has lines of longitude 00:49:59
What do you mean by landfall? 00:50:02
Landfall is where a hurricane 00:50:04
is expected to strike land. 00:50:06
In the game, we issue watches 00:50:08
and warnings to land areas 00:50:10
that are in the path of the hurricane, 00:50:12
just like we're meteorologists. 00:50:14
What is the difference 00:50:16
between a watch and a warning? 00:50:18
A hurricane watch means 00:50:20
that hurricane conditions 00:50:22
are possible within 36 hours. 00:50:24
A hurricane warning means 00:50:26
that hurricane conditions 00:50:28
What are some of the forces 00:50:31
that affect a hurricane's path? 00:50:33
The hurricane in our game 00:50:35
is heading right for Cuba. 00:50:37
We have a hurricane watch 00:50:39
to issue right away. 00:50:41
But to answer your question, 00:50:43
there are some people at NOAA 00:50:45
who could definitely help you. 00:50:47
Thank you so much 00:50:49
for your very valuable help. 00:50:51
No problem. 00:50:53
So long from the Wack Wiles 00:50:55
Kids Club in the sunshine 00:50:57
Don't forget your get-up-and-go sheets. 00:51:00
Hi, I'm Kaylee, 00:51:02
and my friends and I 00:51:04
are concerned about the hurricane 00:51:06
in the Atlantic Ocean. 00:51:08
We have a trip planned to SeaWorld 00:51:10
that we don't want to miss, 00:51:12
so we need to learn more 00:51:14
about how to predict 00:51:16
when a hurricane will strike land. 00:51:18
Well, you've come to the right place. 00:51:20
The National Oceanic and Atmospheric 00:51:22
Administration began in 1970 00:51:24
to help track and predict 00:51:26
You sometimes use information you already have. 00:51:29
Do you ever use the tracks of past storms? 00:51:31
Yes. In short terms, 00:51:33
such as days or hours, 00:51:35
a storm's track may be influenced 00:51:37
by a preceding one. 00:51:39
A hurricane turns the ocean 00:51:41
as it moves over the ocean's surface, 00:51:43
bringing cold water from the bottom 00:51:45
to the top. 00:51:47
Oh, I get it. 00:51:49
We learned that a storm needs 00:51:51
warm water for energy, 00:51:53
so if the water on the surface is cold, 00:51:55
We use computers to show us 00:51:58
the track of hurricanes have taken in the past 00:52:00
as a guide to show us 00:52:02
where the current storm may go. 00:52:04
Historical records of hurricanes 00:52:06
go back to about 1492, 00:52:08
the time of Christopher Columbus. 00:52:10
In analyzing the data, 00:52:12
scientists have found that every 10 to 30 years, 00:52:14
hurricanes appear to come in different numbers. 00:52:16
This is called the decadal scale. 00:52:18
Scientists study this record 00:52:20
so that they can figure out 00:52:22
where we are in the cycle. 00:52:24
Wow, that's a lot of hurricanes. 00:52:27
Yes, it is. 00:52:29
And fortunately, not all of them become strong storms. 00:52:31
Some of them don't even make landfall. 00:52:33
We're wondering if a high-pressure system 00:52:35
could prevent hurricanes 00:52:37
from falling on land. 00:52:39
It is possible. 00:52:41
Think of a hurricane as a block of wood 00:52:43
floating in a river. 00:52:45
Where the river's currents go, 00:52:47
so goes the block of wood. 00:52:49
A hurricane is a storm in a river of air 00:52:51
which moves around the globe. 00:52:53
It's caused by areas of high and low pressure. 00:52:55
Since air circulates clockwise 00:52:57
around a high-pressure system, 00:52:59
a storm approaching it might be turned 00:53:01
to the north or northwest. 00:53:03
If the hurricane does make land, 00:53:05
how much land will be affected? 00:53:07
It depends on the size of the storm. 00:53:09
Most storms are about the size of a state, 00:53:11
200 to 300 miles across. 00:53:13
However, in the Pacific Ocean, 00:53:15
there are monster storms 00:53:17
reaching 1,000 miles in diameter. 00:53:19
Why are they so much bigger 00:53:21
The Pacific Ocean is the largest ocean, 00:53:23
so there's a lot more warm water 00:53:25
for them to move over, feeding their growth. 00:53:27
Is there more damage on one side 00:53:29
of the storm versus the other? 00:53:31
Yes, a hurricane is strongest 00:53:33
on its right-front quadrant 00:53:35
because it rotates counterclockwise 00:53:37
and the speed of a hurricane 00:53:39
must be added to its wind speed. 00:53:41
So the right-front quadrant 00:53:43
is moving faster toward you. 00:53:45
I don't think we want to be 00:53:47
on that side of the storm for sure. 00:53:49
Good luck with your project. 00:53:51
Thanks so much. Bye. 00:53:53
In another weather development, 00:53:57
there is a high-pressure system 00:53:59
over the central area of the United States. 00:54:01
It is moving towards the southeast. 00:54:03
I'm meteorologist Lisa Moser with this update. 00:54:05
I think we need to form a new hypothesis. 00:54:07
Why? 00:54:09
Because now there's a high-pressure system 00:54:11
that might keep the hurricane away. 00:54:13
So what's your new hypothesis? 00:54:15
I think it should be if the high-pressure system 00:54:17
moves to the southeastern part of the United States, 00:54:19
then the hurricane will not hit Florida. 00:54:21
I don't want to take my chances and go to Florida. 00:54:23
Dr. Dean knows a lot about pressure. 00:54:25
Maybe we should go talk to him. 00:54:27
That's a great idea. 00:54:29
But first, I think I just fixed my coaster. 00:54:31
Check it out. 00:54:33
Hi, Dr. Dean. 00:54:39
Hi, guys. 00:54:41
I have my tornado box finished. 00:54:43
Do you want to see it? 00:54:45
How does it work? 00:54:47
Remember, we went over probabilities 00:54:49
last time we were here. 00:54:51
You've been talking about hurricanes for too long. 00:54:53
Here we go. 00:54:55
That is really interesting. 00:55:03
How does it work? 00:55:05
In this case, it doesn't spin 00:55:07
because of the Coriolis effect. 00:55:09
The fan pushes the air out the top, 00:55:11
and then air going through the slots on the sides 00:55:13
will form into a vortex with a counterclockwise rotation. 00:55:15
So what's happened? 00:55:17
We think it's going to be okay to make our trip to Florida. 00:55:19
How do you know? 00:55:21
Let's start with clouds. 00:55:23
We learned that clouds form as warm moist air rises and cools. 00:55:25
This cool air condenses to form clouds. 00:55:27
It's this condensation that gives energy to hurricanes. 00:55:29
Do you know why the air cools when it rises? 00:55:31
No, I hadn't thought about it. 00:55:33
Moist air rises to a higher elevation 00:55:35
with less pressure, it expands. 00:55:37
Expansion is a cooling process. 00:55:39
Let me show you. 00:55:41
Blow on your hand like this. 00:55:43
It's pretty warm. 00:55:47
Now blow with your lips like this 00:55:49
so the air has to expand. 00:55:51
Neat. 00:55:53
It's much cooler. 00:55:55
Isn't science wonderful? 00:55:57
I'm sorry I interrupted you. Keep going. 00:55:59
We've been watching hurricanes very carefully 00:56:01
and plotting its location on the hurricane tracking chart. 00:56:03
We know that hurricanes in our part of the world 00:56:05
start in the Atlantic tropical waters 00:56:07
and move to the west. 00:56:09
Dr. Brown taught us 00:56:11
how LIDAR measures the amount of water vapor in a hurricane. 00:56:13
That's important 00:56:15
because the amount of water vapor 00:56:17
determines the strength of the storm. 00:56:19
Don't forget what the hurricane hunters were able to find out. 00:56:21
We learned that there are a lot of factors used 00:56:23
to predict the probability of landfall. 00:56:25
But we think the key to this case 00:56:27
is a high pressure region 00:56:29
in the southeast part of the United States 00:56:31
that may block the approach of the storm. 00:56:33
What do you think, Dr. D? 00:56:35
It sounds like you've really worked hard on this. 00:56:37
We're going to talk about the probability of a hurricane. 00:56:39
But remember, we can only talk about probabilities. 00:56:41
You can't know for sure. 00:56:43
Wait. Here comes a Weather Channel report. 00:56:45
Hurricane Ichabod has been quite active 00:56:47
the last 12 hours. 00:56:49
The eye of the storm was tracking northwestward. 00:56:51
But if you recall, 00:56:53
a high pressure system building in the southeast 00:56:55
is becoming stronger 00:56:57
and moving towards the hurricane's path. 00:56:59
Now when these two systems collide, 00:57:01
the ridge of the high pressure 00:57:03
is causing the storm to curve its track 00:57:05
into a northeasterly direction. 00:57:07
Therefore, the hurricane watch 00:57:09
has been discontinued over Florida. 00:57:11
The News Channel just confirmed our hypothesis. 00:57:15
We think there's a high probability 00:57:17
that the high pressure system 00:57:19
will keep the storm off the shore. 00:57:21
So we've decided to go to Florida. 00:57:23
Well, I certainly hope that you're right. 00:57:25
I was going to a conference in Florida. 00:57:27
I decided to stay here instead. 00:57:29
You may be missing some nice weather. 00:57:31
Well, I don't think I want to take any chances. 00:57:33
Okay, Dr. D. 00:57:35
You may be sorry. 00:57:37
Yeah! 00:57:39
This is awesome! 00:57:41
We're so lucky to have such great weather. 00:57:43
Too bad Dr. D. 00:57:45
didn't go to his conference. 00:57:47
Sunny skies, no rain, 00:57:49
and the temperatures are just right. 00:57:51
Oh, I should have taken my chances 00:57:55
and gone to Florida. 00:57:57
Okay, I mean, that's... 00:57:59
Was he good? 00:58:01
Look forward to even more exciting mysteries 00:58:03
next season when the NASA Wi-Files 00:58:05
becomes the NASA Sci-Files. 00:58:07
In the hurricane, I mean... 00:58:09
I think he feels like it because 00:58:11
he's soaking wet. 00:58:13
I'm getting a little wetter here. 00:58:15
Well, I mean, it's a storm. 00:58:17
I mean, people don't go out in storms dry. 00:58:19
I mean, this is realism here. 00:58:21
What's that? 00:58:23
The NASA Wi-Fi files 00:58:25
The NASA Wi-Files is made possible 00:58:27
through the generous support of 00:58:29
Bush Gardens, SeaWorld, 00:58:31
and NASA Langley Research Center's 00:58:33
Aerospace Vehicle Systems Technology Office. 00:58:35
All right, all right. 00:58:37
Valoración:
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Idioma/s:
en
Niveles educativos:
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Autor/es:
NASA LaRC Office of Education
Subido por:
EducaMadrid
Licencia:
Reconocimiento - No comercial - Sin obra derivada
Visualizaciones:
459
Fecha:
28 de mayo de 2007 - 15:33
Visibilidad:
Público
Enlace Relacionado:
NASAs center for distance learning
Duración:
58′ 42″
Relación de aspecto:
4:3 Hasta 2009 fue el estándar utilizado en la televisión PAL; muchas pantallas de ordenador y televisores usan este estándar, erróneamente llamado cuadrado, cuando en la realidad es rectangular o wide.
Resolución:
480x360 píxeles
Tamaño:
351.18 MBytes

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