Lesson video

Hi everyone.

My name is Miss Dhillon.

And last lesson we were exploring the question.

What makes up the weather? Can you name all of the six components of weather? I know that's a challenge, but we love challenges because they really help us to grow.

So let me help you and start you off.

One of the components is temperature.

Can you name the rest of the five components of weather? Try your best.

Well done if you managed to name some of them.

So you should have said the six components are temperature, cloudiness, humidity, wind, precipitation and finally atmospheric pressure.

And that is a tricky one to remember.

So well done if you've got that.

Okay.

So the question we're exploring in today's lesson is why does it rain? This is what the structure of the lesson is going to look like.

We will be going through the star words.

Then we will start by looking at the concept of a hot air balloon and how warm air rises.

Then we will move on to looking at using a compass for directions.

Finally, we will look at why does it rain? and different types of rainfall.

And in today's lesson, we will be looking at three different types of rainfall.

Make sure you have a pencil or a pen, an exercise book, or paper and your brains ready for today's lesson On the screen, you can see the star words for today's lesson.

I will be explaining these star words in more detail throughout the lesson.

Let's start by saying them out loud using my turn your turn.

North, South, East, West, compass, precipitation convectional, frontal, orographic.

Wow, well done, you did a really good job, especially with the last four key words.

They are quite long and tricky to say, but don't worry.

You will get lots of practise to saying them in today's lesson.

One of the key things to remember when learning about rain is that warm air rises.

What does warm air do? Good it rises.

And the reason warm air rise is because it is less dense or it's lighter than cool air.

Cool air, however sinks.

What does cool air do? Good it sinks.

And this is because it's more dense than warmer air and therefore means it's heavier which means it sinks.

A hot air balloon rises because the air inside it is warmed by a what can you see on the screen? A flame, good job.

So when the flame inside the hot air balloon heats up, the warm air is less dense than the surrounding air.

And therefore the hot air balloon starts to rise.

Now, when you want to bring the hot air balloon back down the flame inside the hot air balloon is turned off.

And when this happens, the air slowly and gradually starts to cool down and get more and more dense.

Which means it gets more and more heavier.

And as a result, the hot air balloon starts to descend or come down.

So the key message here is that warm air rises.

Good job and cool air sinks.

Now let's think about the terminology of dense.

Can we add that to our explanation? So warm air rises because it is less dense and cool air sinks because it is more dense.

Good job.

Now we're going to make sure that we are remembering the key learning.

So I'm going to test you on it.

You will need to point up if you think it rises and you will need to point down if you think it sinks.

Are you ready? First one is cool air.

Does it rise or does it sink? Show me with your hands.

Can you challenge yourself to explain why? Okay, so you should have said cool air sinks.

Well done if you've got that correct.

And if you challenge yourself, you would have said it sinks because it's more dense or heavier than warm air.

Ready for the next one.

Warm air.

Does it rise or does it sink? Can you also explain why it does so? Okay, so you should have said warm air rises.

Well done.

And if you challenge yourself, you would have explained it rises because it is less dense, which means it is lighter than cool air.

And that's why it rises.

Good job.

Now I would like you to pause the video, to complete the task on the screen.

Use the keywords in the box to complete the sentences.

You can see the answers are now on the screen.

Did you manage to put the correct words in the missing gaps? Well done if you did.

I know it's tricky to remember if it's more or less dense.

So well done for paying attention.

Now as a geographer, it is really important to know how to use the compass directions.

Maybe you already know them.

Let's have a look at the four directions.

You have North, East, South and West.

Can you say that loud for me starting from the top at North and going clockwise.

North, East, South and West.

Good job.

Okay, these are the four directions and there's a clever way to remember the order on a compass.

The first letters of these words will help you remember the directions.

So let's look at the first one.

Never Eat Shredded Wheat.

So the letters, the word starts with the letters, N, E, S W.

And that stands for North, East, South, West.

So you can see how remembering, Never Eat Shredded Wheat, can remind you that you start with North and going clockwise you can write down East, South and West.

Now there's another one.

Maybe this one might appeal to you to help you remember the directions.

Never Eat Slimy Worms. Yuck! so maybe that one is more memorable for you.

So you can pick and choose which one will help you remember the directions.

So let's see if you can remember those.

Can you say them out loud for me starting at the top with N going clockwise to E to S to W.

Pause the video now, if you need a few seconds to think.

Okay, so you could have used, Never Eat Shredded Wheat or Never Eat Slimy Worms to help you.

And you should have said North East, South, and West.

High five, if you've got that correct.

Well done.

Now let's have a look at the make up of clouds.

Clouds are made up of tiny water droplets.

As more and more droplets join together, they become really heavy and start to fall from the cloud as rain.

Warm air can hold more moisture than cool air.

So when the warm air is cooled and cold moisture condenses.

What does condenses mean? Good condenses mean the gas turns into a liquid and this causes the rain to happen.

So, to recap that learning, can you now pause the video to complete the task on the screen.

Did you remember that correctly? Well done for listening.

Clouds are made up of tiny, tiny water droplets and rain is formed when they condense and they joined together and they fall as rain.

Let's now think about the question.

Why does it rain? We looked at the water cycle in last lesson and this explains why it rains Number one, the heat from the sun turns moisture or water in plants in leaves in oceans, lakes and rivers into water vapour through evaporation.

So the first stage is evaporation.

This water vapour then rises and cools and changes into tiny water droplets to form clouds.

The water droplets in the clouds join together to make bigger water droplets.

When it gets too heavy, they begin to fall as rain and we call this, good job precipitation.

Well done.

So this water cycle explains why it rains.

Now, how do we know it's likely to rain? Have you ever predicted that it's going to rain? What makes you think might rain? Well, maybe, you know, it's likely to rain, when you see dark clouds approaching.

They are dark because they offer full of water droplets that block out the sunlight from the sun.

That is why they are dark clouds.

Now we're going to move on to the types of rainfall.

There are three main types of rainfall.

We're going to say this out loud, using my turn, your turn.

Convectional rainfall, Frontal rainfall, Orographic rainfall.

Good job, you are starting to sound like geographers.

Now we're going to learn a bit more about these different types of rainfall.

Let's start with convectional rainfall.

This happens when the ground is heated up by the sun.

When the land warms up, it heats the air above it, and this causes the warm air to rise.

As the air rise, it cools and condenses, which means it turns into water droplets and forms clouds.

Water droplets then joined together, and when they get really heavy, they fall as rain.

This type of rainfall is very common in tropical areas, but in also areas such as the Southeast England, where they usually have quite warm sunny spells.

Pause the video now to complete the task on the screen.

Use the key words in the white box to help you fill in the missing gaps.

Here are the answers.

The key words are in bold.

So take a few moments to check your answers.

How did you do? Well done for using all the keywords in the white box.

I know you're paying very close attention to the new keywords that you're learning in today's lesson.

We are now going to be looking at Frontal rainfall.

Frontal rainfall occurs when the warm air mass meets the cold air mass and the warm air is forced to rise above the cold air, creating this front.

This is why it is called frontal rainfall.

As the warm air rises it cools and the water vapour condenses into water and falls as rain drops.

This is why it rains heavily along the front.

It's now time for you to complete a task.

Are the statements on the screen true? Or are they false? Perhaps you also want to challenge yourself that if you find a false statement, can you change it to make it true? Pause the video now to complete the task on the screen.

Did you realise that all of the statements were false.

Well done if you did.

If you change these into true statements, this is what you might have written.

For A, the correct statement should have been that frontal rainfall occurs when warm air mass meets a cold air mass.

And for B, the warm air is forced to rise over the cold air, not the other way round.

And this is what creates the front.

So well done if you wrote those statements.

Now we are going to look at Orographic rainfall.

My turn, your turn.

Orographic.

Mountains can help to form rain.

And when this happens, it is called orographic rain.

Orographic rainfall, if you look more closely at the diagram, if you look at the arrow going up the mountain, orographic rainfall is rain that is produced from the lifting of moist air over a mountain.

The moist air then rises, condenses, and this is what produces dark clouds, which then lead to precipitation.

So orographic rainfall is rain produced because moist air is lifted over a mountain.

So you might want to remember that for orographic, because it helps you remember that moist air is lifted over the mountain, and then it condenses to form clouds, and then that leads to precipitation.

So the key word orographic refers to anything to do with mountains.

So orographic means mountains.

It's referring to mountains.

So orographic rainfall occurs because of mountains.

Now, usually the side of the mountain that faces the sea receive most of the rain.

This, therefore creates a rain shadow.

Let's look a little bit closely at the diagram.

A rain shadow is created on the other side of the mountain, where there is not as much rain.

This means that this side of the mountain in the rain shadow usually has less vegetation.

Vegetation means plants and trees.

And this is what you can see on the diagram on the side of the rain shadow.

It is not green because none of the vegetation grows on that side because there is not enough rain.

This can be seen very clearly in the Himalaya Mountains.

The Himalayas stretch across the North Eastern portion of India, and they cover approximately 2,400 kilometres.

And they pass through the nations of India, Pakistan, Afghanistan, China, Bhutan, and Nepal.

In the white box, you can see a section of the Himalaya with the tallest points covered in snow.

Look at the red cross on the diagram.

Use the compass on the screen to help you follow.

On the South side, which direction is South side? Good, on the South side, the mountain is green.

This is because there is lots of orographic rain.

Why do you think it's green? Good, because there's lots of orographic rain.

That means there's lots of vegetation or trees and plants growing on that side.

And that's why it's green on this satellite image.

Now let's have a look at the cross on the diagram.

This time, you can see it's on the Northern side of the mountains.

Can you see that a rain shadow has been created? How can you tell that the rain shadow is created on the Northern side of the Himalayas? Say that a loud.

Good, you should have said that you can see that a rain shadow has been created because on this side it is not green.

And if it's not green, that means there are no plants or trees growing on that Northern side of the Himalayas.

Well done.

Really good recall.

Now because of the rain shadow, fewer plants can grow here and that's why it is not as green as the South side.

So the bottom part of that white box is the South side.

And it's very green because there's lots of orographic rain.

Well done.

And on the North side is a rain shadow.

Well done.

And here plants and trees do not grow because there's not enough rain.

And that's why is not green on this satellite image.

So team, it is now time for you to complete a task.

Pause the video now to complete the task on the screen.

Use as many keywords given to you to help you write your answer.

Here is an example of what you might have written.

All the key words used are in bold.

Take a few seconds to read the model answer.

How many of those key words were you able to use in your answer? Wow, well done.

I know you're trying really hard to use all the key words that you've learned so far.

Well done for putting so much effort into using them.

Now he is the final task for today's lesson.

Now that you know, all three types of rainfall, I would like you to match up the type of rainfall with the correct description.

Pause the video now to complete the task on the screen.

Here are the answers.

Take a few moments to check your answers against the answers on the screen.

Thank you so much for your effort today.

And I really hope you enjoy the rest of the day.

And I can't wait to see you again, lesson four, where we will be exploring the question.

Why does the UK have wild weather? Bye everyone.