Lesson video

Hello, my name is Ms Gilyeat and I'm going to be your geography teacher for today.

In today's lesson, we're going to learn how we can show height and relief on a map.

It is the sixth lesson of becoming a geographer topic.

I'm looking forward to teaching you, let's get going.

Our lesson outcome for today is that you can use an OS map to describe the height and relief of the land.

Now we have four keywords for today's lesson, which will be highlighted in bold throughout the lesson if you need to refer back to them.

The first one is sea level.

So this is the average level of the world's oceans, which we use as a baseline to measure the height of the land.

Contours, so lines on an OS map that show areas of equal height.

Spurs, which are elongated ridges that extend downwards from a hill or a mountain.

And valleys are lower-lying areas of land between two higher areas of land.

We have got two learning cycles for today's lesson.

Our first learning cycle is we are going to learn how is height shown on an OS map.

We are then going to learn about how do contours show the relief of the land.

Let's get going with learning cycle one, "How is height shown on an OS map?" Now, maps show us what the world looks like.

But because maps are on a flat surface, it's hard to share the height and the actual shape of the land.

Okay, so maps are 2D, but of course we know that real life is not flat and it's full of shapes and different sizes.

So I've got a photograph on the boards and on the slide of a beautiful mountain range.

I want you to have a think, how could those mountains be shown on a map? So how could we get the idea across that the land can be of lots of different shapes and heights? How can we share that on something which is flat or two-dimensional? Now there are different ways that height can be shown on a map.

Small-scale maps, now as a quick recap, a small-scale map shows a large area but in not much detail.

So small-scale maps often use colours to identify the height of the land.

Okay, so if we have a look at this slide here, we've got a map of Europe.

Now the Europe map has been shaded in different colours, so there's green, yellow, and grey.

Now if we have a look here, we have got a key, so we can see that the different colours represent different heights of land.

So areas have been shaded in green are not high above sea level, they're between 0 and 200 metres, or 199 metres above sea level, okay? If the area has been shaded in a lighter yellow colour, the land is above 200 metres but less than 1,000 metres above sea level.

If the area of land is shaded in a darker yellow, it's above 1,000 metres but less than 2,000.

Now the areas that have been shaded in a grey, those are the highest areas in Europe, okay? So those are mountain ranges, okay? And they are all over 2,000 metres above sea level.

So we can see there that there's parts of Norway, Sweden, Switzerland, Italy, and Austria which have been shaded in that, have got part of the country at least shaded in that grey colour, so those are the highest areas located in Europe.

Now I want you to have a look at that map and I want you to find some areas of low land, okay? So pause the video, you could do this by yourself or you could have a chat with the person sat next to you.

Where's quite low-lying areas within Europe? Then, can you find any high or mountainous land? Okay, so let's have a look then.

So low, flat-lying land there, you've got some in northern Poland, there's quite a lot in the UK as well, there's quite a lot in France, Belgium, Holland, Denmark.

All of those areas have got a lot of flat low-lying land.

Mountainous, high land, now the main area is the mountain range called the Alps, and that's located in France, Switzerland, Austria and Italy.

Now larger-scale OS maps, now let's remember, a quick recap.

A larger-scale map shows a smaller area but in a lot more detail.

Now these types of maps tend to use something called contours to show us the height of the land.

Now contours are faint little orange lines.

So if we have a look at my slide, we've got a picture of a section of an OS map and those little orange lines there join up areas of equal height, okay? They are called contour lines.

So I've labelled two for you there.

Now you will notice that these contour lines have a number on them.

Now they don't all have numbers on them, but when you're looking at an OS map, at least some of the contour lines should have numbers.

If there's ones that don't, you can usually figure out what the number is from looking at the other ones, okay? Now that number tells us specifically how many metres above sea level you would be at that point, okay? So for example, that orange line there, that contour line, if you were stood anywhere on that line, okay, in real life, you would be 370 metres above sea level, okay? So if I stood there, if I stood there, exactly the same height, 370 metres.

It's a bit like dot to dot, it joins up areas of the same height.

If I stood anywhere at that height, I would be 350 metres above sea level.

Now you have to be careful, sometimes it's not always obvious to see where the number is, so you might have to follow the contour line for quite a long time until you find what number it is.

Let's check our understanding.

Which two of the following statements are true? A, maps are usually 3D, or three-dimensional.

B, contours show areas of equal height.

C, contours show the height of the land above sea level.

D, contours show the height of the land in feet.

Pause the video and have a go.

So the correct answers are B and C, contours show areas of equal height and contours show the height of the land above sea level.

Okay, so we have learned they show areas of equal height.

Now they often go up in intervals.

Now it's usually at 10-meter intervals, but not always.

Sometimes they might even go at 5-meter intervals or 20-meter intervals as well, okay? You just have to check the number.

Now, through this they create a clear way of showing the height but also the shape of the land on a 2D or a flat map, okay? So we know what the number is, we know what the height is, and we can actually start to look at the patterns of the lines to indicate what the shape is like.

Now, contour lines on maps near the sea will have a lower number, whereas contours on mountains will have much higher numbers.

Now, if I was stood on a beach next to the ocean or the sea, I would be at 0 metres above sea level because I am at the same height as the sea.

As you go further inland and you walk up a mountain, then you are gaining height above that sea level, okay? So then the contour line number would get higher.

Now, for example here, you've got Ben Nevis there, which is located, or the top of Ben Nevis, is at 1,345 metres.

That means it's 1,345 metres above the sea, okay? As you walked downhill and got closer to the ocean, the number decreases.

So at that point there you can see on the map you would be at about 40 metres above sea level.

Let's check our understanding, so true or false? Contours are only used for showing mountains and hills.

That is false, and can you tell me why? Contours are not only used on hills and mountains.

Contour lines show areas of equal height at 10-meter intervals above sea level.

Now the top of the hill or mountain will be shown by a ring, a ring contour, and sometimes a spot height.

Now that's what we mean by a ring, so it gives the circle, sorry, the contour line joins up to create a ring so you could go through it, okay? So that's an example of a ring contour there at 380 metres, okay? Now you've got a spot height there.

Now a spot height is a number with a little dot and it tells you the exact height at that point in metres above sea level.

Now often these spot heights are put at the tops of mountains on a map, okay? So you would know if you were going to walk up that hill how high above sea level you would be at the top of that mountain.

So for this one, if I was to walk up to the top, I would be 388 metres above sea level.

Okay, yeah, so, as we said, that point there could be anywhere between 370 and 380, and that point there could be anywhere between 350 and 360, but 388 is the exact point and the exact height of the land.

A ring contour is a circle which has no other contour lines within it.

This means it's the highest contour line, okay? So the reason there isn't any above it because there's no land that's higher than that point.

So there's a nice picture on the slide here which shows a mountain, okay? And where the contour lines would look like if the mountain in 3D compared to what it looks like on a map.

So there's the ring contour, okay? What it would look in real life compared to what it would look like in a map, so you get these kind of nice ring formation patterns.

What do you think the spot height would be at the top of this hill? So you can see there the highest ring contour is at 50 metres, okay? So 50 metres above sea level.

But there's actually a little bit of land which is higher than that contour line.

So I want you to take a guess.

How many metres do you think that you would be at if you were to be stood at the top of that hill? Now remember it has to be less than 60 metres because there's not a ring contour for 60, so somewhere between 50 and 60 metres.

Izzy here thinks, "I think the spot height would be about 53 metres," and I think Izzy's probably about correct.

Now at this point there's no exact way of knowing, but roughly we can see that it is just a little bit higher than 50.

Now spot heights aren't always at the top of the hill.

So I've got a picture of a section of a map there.

Now we can see here there are two spot heights, okay? Can you see which one's at the top of the hill and which one isn't? Okay, so we should be able to see that the spot height that isn't at the top of the hill is 389 metres, okay? First of all, because it's not in a ring contour, but also it's a lower number so it means it's lower down as well.

If you were to be at the top of the hill, you'll be at 792 metres above sea level.

Okay, let's check our understanding.

So what height above sea level is this contour line? You have to be really careful here because not all the contour lines have numbers on them.

So you might need to look at the ones that do have numbers on and then work out the difference of what intervals they are going up in.

So Laura is correct, it's at 520 metres above sea level, because we can see there the darker or the line that's been highlighted closest is at 500 and the lines are going up at 10-meter intervals.

Well done, Laura.

Where is the top of the mountain on the map and how high is it? So have a look, so where's the top and how high is it? So Laura's doing it again.

"This is the top of the mountain and it's at 751 metres high." Well done, Laura, again.

We've got another spot height there, okay, which is telling us how how you would be if you walked up that mountain.

Next one, roughly what height above sea level is this point? Okay, this is a tricky one.

Look at the contour lines, look at which ones it would be between, and then you're going to have to give a rough estimate because it's not exactly located on one contour line.

So Laura has put, "Anywhere between 520 metres and 530.

We don't know for sure." And you're right, Laura.

We don't know exactly at what point or what height that is because there isn't a number on it, but we know that it's somewhere between 520 and 530 metres above sea level, good work.

Right then, let's move on to our first task for the lesson.

What I would like you to do is label the following features on the map.

Now this is being put on a worksheet that's attached to this lesson.

So the labels are "a spot height not at the top of a hill," "a place at 310 metres," "a place between 330 and 340 metres," and "the top of a hill." Once you had found those places, I would then like for you to explain why you have placed each label below where you have, okay? Now I've put a sentence starter to get you going.

So for example, for the first one, if you place "a spot height not at the top of the hill" and you found that, I want you to tell me why you've put that there, so, "I know this because.

." Pause the video and have a go at Task A.

Okay, let's go through the answers to this task.

So, between 330 metres and 340 metres.

I know this because it's between the 330-meter and 340-meter contour line, well done.

Top of the hill because there is a ring contour and it is the highest spot height, also correct.

310 metres as it is on the 310-meter contour line.

And a spot height not on a hill, I know this because it hasn't got a contour ring around it.

How did you do? Right then, let's move on to our second learning cycle, which is, "How do contours show the relief of the land?" Now the relief of the land is the shape, so that might be a new word that you've learned today.

So if we're thinking about the relief as land outside, it's not about, oh, feeling a sigh of relief, a totally different word.

It's about the shape of the land that we can see outside.

Now I've got a lovely picture on the slide here and we're gonna learn about some words that you might use to describe what the shape and the relief of the land look like, okay? So, spurs are elongated ridges that extend downwards from hill or mountain.

Okay, so on the slide there I've highlighted where a spur is, so it's a piece of land coming down to the valley bottom, so that is a spur.

Valleys are lower-lying areas of land between two or higher areas of land, okay? So a valley is like that.

Now you've got different types of valley.

You can have a V-shaped valley, so it might have a quite narrow bottom and look like that.

Or you could have a U-shaped valley, which is quite the shape of a U basically so it has quite a large flat bottom and then steep valley sides.

Now we're not going to learn this in today's lesson, but valleys are created by different processes.

Now I've got another lovely picture on the slide here.

So how would you describe the relief of this landscape? So think about descriptive words that you would use for the shape of things.

So steep, flat, gentle.

Can you pick out any of those keywords that we've just learned? So you could pause the video, you could even write your own answer down or you could have a chat with the person you are sat next to.

So Alex has given an answer here.

"This land has very steep-sided hills and a flat valley bottom." Perfect description there, Alex, well done.

How would you describe the relief of this landscape? Pause the video and have a chat with the person you are sat next to.

"This land is very flat." Well done, Sophia, you're absolutely spot on there.

If that was to be on a map, you wouldn't see many contour lines 'cause there's not much difference in the shape of the land.

Okay, let's check our understanding.

Which two of these statements are describing relief? So A, the area is close to the beach.

B, the area is hilly with steep-sided valleys.

C, the area has many trees.

Or D, the area is flat.

So which is talking about relief or the shape of the land? The answer is B and C.

The area is hilly with steep-sided valleys, and C, the area is flat.

Now practising using contours allows us to understand the relief of the land by looking at a map.

So the more that you understand and the more that you look at maps, you'll start to be able to pick out the little patterns in the contour lines, which helps you get an idea of what that area looks like in real life, okay? Now when the land is very steep, the contour lines in a map will be very close together.

Okay, so I've got a picture here with the accompanying map of the area, right? So contour lines that are really closely packed.

That basically is saying that there's a large difference in height in a small area because each of those contour lines represents a change in height of land, okay? So close together contour lines represents steep land.

When the land is very flat, there will be no contour lines or the contour lines will be very spread apart.

Now that tells us there isn't really much of a change of height in a large area.

So for example, the slide here, we've got a flat landscape.

Now there's an accompanying map.

Now it's not actually the same place, but it's the same idea.

So there's no contour lines there because there's no change in the shape of the land, okay? It's all completely at the same level.

Okay, so you've got steeper contour lines when they're close together, and when they are further apart it shows the land is more gently sloping.

Now what we can do is we can draw two-dimensional profiles of a hill by looking carefully at the contour lines and thinking about where is high and where is low.

So I'm gonna show you a simple example of this.

So on the slide we can see some ring contours, okay? Now as we have learned, ring contours represent mountains, because as you go up, okay, you get areas of the same height but in smaller circles.

So you've got high land up there and lower land down there.

Now if we were to put those onto or draw back what that looks like in real life, it would look something a little bit like this, okay? So you've got areas of the same height at the bottom and at the top, so you've got quite a uniform or a symmetrical mountain there, if you like.

Let's check our understanding.

Is location A or B in the least steep areas on this map? So look at the contour lines.

Are they close together or are they far apart? So area A is the least steep as the contour lines are spaced further apart.

Now drone footage can help us visualise the information on a map.

The video shows the land viewed from point A looking over to point B.

The land drops steeply to a lake and then steeply back to another point, okay? So we can look at this footage to see what that actually looks like on a map.

Features such as a river valley and a spur can be seen using contour lines, okay? So a valley looks like this.

So you've kind of got V-pointy things but they go uphill because that shows the further you got the valley, the further height you are gaining.

Spurs have a shape like this, so they look like Vs but they are going downhill, okay? So V-contour shapes pointing uphill shows a valley like that and V-shaped contours pointing downhill show a spur like that.

The valley, that's that one, and that is a spur, so that's what that actually looks like in real life.

Let's check our understanding.

Have a look at the section of a map here.

Can you see where is a valley on the map? There you go.

Did you get that right? So you've got Rest Gill there, there's a river running down, and let's check, that's because the Vs are going up like that.

Okay, next question.

Where is a spur on the map? Okay, there we've got a spur because they are pointing downhill like so.

Okay, we are moving on to our second task, so Task B.

What I would like you to do is draw a 2D profile of the hills shown by each of these set of contours.

Now there is a worksheet to go this lesson, so it might be useful for you to do this on the worksheet so you can get it as accurate as possible.

So pause the video and have a go at drawing the actual what the hill would look like for each of those set of contour lines.

Your second task here is to match each number to the following descriptions, okay? So we've got numbers 1 to 4 labelled on the map, okay? Right, and what you need to do is match each number with this description, or each of these different descriptions.

So summit of the mountain, very steep side of the mountain, valley with a river running down it, and spur leading to the summit.

Can you match 1, 2, 3, and 4 with each of those sentences? Okay, let's check our answers.

So for the first part of this task, that's what your first mountain should look like.

Because the rings are quite uniform and quite symmetrical, your mountain should look similar.

For the second one, the mountain is steeper on the left because the contour lines are closer together, and it's more gently sloping on the right because they are further apart, so your mountain should look like that too.

Now this was a tricky one.

We can see here there are two rings at the top.

Now that means there are two little hilltops on the mountain, so your mountain should have two little hilltops as so.

Okay, let's check our understanding for this task.

Now, number 1 was a valley with a river running down it.

Number 2, very steep side of the mountain we can see there because the contour lines are super close together.

There's 3, a spur leading to the summit.

And 4, you've got the summit of the mountain, so you've got a spot height there of 950 metres.

That's how high you would be if you were stood at that point.

Right then, let's get a summary for today's lesson.

So, first of all, contours show the height of the land on a map.

Spot heights give the exact height of a place in metres.

Contours that are far apart show an area of flat land.

And contours that are closer together show steeper land.

Okay, that's it for today's lesson.

Well done, it's been quite a lot of tricky concepts there, but you've done a great job.

Right, I'll see you later, bye.