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Hi geographers, my name is Mr. Lolledge and I'm looking forward to learning with you today.
Today's lesson is Living near Volcanoes and that's from the unit Mountains and Volcanoes, What, Where and Why? This is going to be a great lesson with some tricky concepts, but I'm here to help and we can learn together.
Let's get started, shall we? By the end of the lesson, you'll be able to describe and explain the impact of volcanic eruptions on people and understand why some people choose to live near volcanoes.
The keywords we will be using today are, minerals, geothermal energy and lahar.
Minerals are chemical substances that are formed naturally and are found in the ground or in rocks.
Geothermal energy comes from heat contained within Earth's crust.
A lahar is a mud flow formed when volcanic ash mixes with water, rain or melted glacier ice.
Our lesson today is going to be split into two parts.
The first part is "The Advantages of Living near a Volcano," and the second part is "The Disadvantages of Living near a Volcano." So let's begin with our first section.
What are the advantages of living near a volcano? 350 million people live in close proximity to an active volcano.
That's a volcano that could erupt at any minute.
This means one in 20 people live within dangerous range of a potential eruption.
Mount Etna is located in Sicily and is Europe's highest and most active volcano.
It is 3,357 metres high when measured in July, 2021.
Interestingly, its height changes whenever it erupts, which is quite frequently.
At one stage, Mount Etna erupted continually for 13 years.
That was between July, 1979 and December, 1992.
25% of Sicily's population, which is at 4.
8 million, live on Mount Etna's slopes.
On average, there are 20 active eruptions happening each day across the world, but not all of them are serious.
In Iceland, there are 130 volcanoes with one eruption approximately every 10 years.
Let's have a quick pause here just to check our understanding of what we've learnt so far.
How many people in the world live in close proximity to a volcano? Is it A, 150 million people? B, 250 million people? Or C, 350 million people? Pause the video now.
See if you can answer that question.
Welcome back.
The answer to that question was C.
350 million people live in close proximity to a volcano.
That's one in 20 people.
So that brings us to two really important questions here.
Why do some people choose to live near a volcano? Does everyone have a choice where they live? Let's find out, shall we? Unfortunately, not everyone does have a choice where they live.
Financial restrictions, family, jobs and dependency on the land are all reasons why some people are not able to move away from active volcanoes.
However, there are many advantages of living near a volcano and reasons why some people are willing to take the risk of living near to an active volcano.
Let's go through them.
Firstly, farming.
Volcanic rocks and ash contain magnesium and potassium.
Once weathered or broken down, they provide a rich, fertile environment for different types of agriculture to grow.
There are 180 vineyards in the foothills of Mount Etna, Sicily, due to fertile soils there and approximately 25 million bottles of wine are produced in Sicily in total each year.
That's a third of a bottle for everyone in the UK, or one very large glass.
Citrus trees, salad vegetables, tomatoes, herbs, market garden vegetables, coffee and flowers are all items that grow well due to their volcanic environment.
All those items can then be transported and sold around the world.
Okay, we've got another check for understanding here with a true or false question.
Volcanic soils are bad for growing crops.
True or false? Pause the video now.
See if you can answer that question.
Welcome back.
So the answer to that question is false.
Volcanic soils are not bad for growing crops.
Right, can we justify our answer here? Is it A, because volcanic soils are good for growing crops as volcanoes make the soil rich in minerals and very fertile? Or is it B, volcanic soils are bad for growing crops as they burn the crops? Pause the video now.
See if you can justify your answer.
Welcome back.
So the correct answer to that one was, yes, A.
Volcanic soils are good for growing crops as volcanoes make the soil rich in minerals and very fertile.
Well done if you answered that question correctly.
Another advantage of living near volcanoes is mineral extraction.
Yes, I'm talking about diamonds.
Graphite is a solid, black rock found in volcanoes.
When volcanoes erupt, graphite crystallises under the extreme heat and pressure inside volcanic vents.
This changes graphite into diamonds, which are then thrown to Earth's surface by the force of the eruption.
Without the extremes of heat and pressure that make a diamond graphite can be used in pencils for writing with.
Our next advantage of living near volcanoes is geothermal energy.
`Geo' means of the earth and `thermal' means heat.
Geothermal energy is heat that occurs naturally in the ground in volcanic areas.
Geothermal energy has been used for centuries for cooking, heating, washing clothes and bathing.
Some geothermal springs are as hot as a bathtub, but many are too hot to enter.
In geothermal plants, heat from underground water is used to drive turbines, which produces energy.
Energy can then be transferred into electricity, which can be used in your home or your school.
In 2021, there were 27 countries that used geothermal energy as an energy provider.
Tourism is another advantage to living near a volcano.
Wouldn't you want to see a volcano? People like to visit volcanoes and volcanic landscapes.
Tourism creates jobs and generates an income for the people who live there.
3 million tourists visit Yellowstone National Park, in the United States of America, every year to see the volcano and geothermal springs located there.
Okay, we've got another check for understanding here.
Which option below is not an advantage of living near a volcano? Is it A, mineral extraction like diamonds? B, geothermal energy? C, the risk of the volcano erupting? Or D, tourism? Pause the video now.
See if you can answer that question.
Welcome back.
So the correct answer to that question was C.
The risk of a volcano erupting is not an advantage of living near a volcano.
It is a disadvantage.
Well done if you got that question correct.
Can you remember the advantage missing? The one advantage that is not listed there? Pause the video now.
See if you can complete that question.
Okay, so the advantage missing was fertile soils, which are good for farming.
Well done if you got that one correct.
Okay, we're onto our first task for today's lesson.
Your task is to create your own advantage of living near a volcano cards.
On one side, I'd like you to write the title of the advantage On the other side, explain why it's an advantage.
Pause the video now to complete that task.
Welcome back.
Let's have a look together.
Does your work include the following advantages with similar information? Here, my first advantage is farming.
Farming is an advantage because volcanic soils are very fertile, which helps farmers grow crops.
My next advantage is mineral extraction.
It is an advantage because diamonds can be found near volcanoes that have erupted.
Diamonds are worth a lot of money.
My next advantage is geothermal energy.
It's an advantage because for centuries, heat from under Earth's crust was used for cooking and cleaning.
Geothermal energy can also be transferred into electricity.
And my last advantage is tourism.
It's an advantage because millions of people visit volcanoes each year.
Tourism generates income for people who live there.
Well done if you included all those four advantages and reasons why they're an advantage.
We're now on to our second part of our lesson, "The Disadvantages of Living near a Volcano." So, there are many disadvantages of living near an active volcano.
Can you think of any? I'm sure you can.
One pupil says, "It could be very dangerous!" And she's certainly right there.
Let's go through the disadvantages of living near a volcano one by one.
Our first disadvantage is lava.
Lava is an extremely hot liquid which reaches temperatures up to 1,200 degrees Celsius that can spill from volcanoes when they erupt.
The intense heat from lava burns everything in its path and can set everything on fire, even when the lava doesn't touch it directly.
While lava can flow quickly at the peak of a volcano, towards the lower slopes where the land flattens, it travels relatively slow, generally speaking through one kilometres and 10 kilometres per hour.
No faster than jogging speed.
However, death or injury can still occur when people choose not to leave an area and find their escape routes have been cut off.
Fortunately no lives were lost in La Palma in 2021.
The eruption of the Cumbre Vieja volcano in La Palma, Canary Islands, destroyed 3000 buildings.
The eruption lasted 85 days and lava reached the town of Los LLanos over 20 kilometres away.
The eruption caused a total of £750 million pounds worth of damage.
Another check for understanding here.
What temperature can lava reach? A, up to 800 degrees Celsius? B, up to a thousand degrees Celsius? Or C, up to 1,200 degrees Celsius? Pause the video now.
See if you can answer that question.
The correct answer there was C.
Lava can reach up to 1,200 degrees Celsius in temperature.
Well done if you've got that answer correct.
Another disadvantage of living near active volcanoes is the ash released from volcanic eruptions.
Ash is not soft and fluffy.
It is a hard and abrasive mix of rocks, minerals and glass.
Ash from volcanoes can bury homes, farmland and roads.
In fact, pretty much everything in its path.
In La Palma in 2021, 200 million cubic metres of ash were expelled.
That's approximately 150 Olympic sized swimming pools worth.
Wow, that's a lot of ash.
Our next disadvantage of living near volcanoes is to do with the gas released from volcanic eruptions.
Volcanoes give out large amounts of gas, which can rise tens of kilometres in the air.
The gases are primarily mixture of water vapour, steam, carbon dioxide and sulphur dioxide.
These gases can irritate the eyes, nose, and throat.
They can also cause permanent lung damage.
In some cases, breathing in the gas can be fatal.
Okay, we've got another check for understanding here.
True or false? Volcanic ash is soft and fluffy.
Is that true or is that false? Pause the video now to answer that question.
Welcome back.
The answer to that question is false.
Volcanic ash is not soft and fluffy.
But can you justify your answer? Is it because A, volcanic ash is a hard, abrasive mixture of rocks, minerals and glass? Or is it because B, volcanic ash is a soft, snow like mixture? Pause the video now to justify your answer.
The correct answer there was A.
Volcanic ash is hard, abrasive mixture of rocks, minerals and glass.
Well done if you answered both those correctly.
Lahar.
A lahar is a mud flow formed when volcanic ash mixes with water, rain or melted glacier ice.
While they may look like rivers of mud, they are similar to fast flowing concrete.
The energy of moving lahar can pick up and transport objects in its path, causing great destruction.
Let's just check our understanding again.
Which option below is not a disadvantage of living near a volcano, A, lava, B, mineral extraction, C, lahar or D, ash.
Pause the video now to answer that question.
Welcome back.
The correct answer there is B.
Mineral extraction is not a disadvantage of living near a volcano.
It is actually an advantage.
Can you think of the disadvantage missing? Pause the video now to answer that question.
The disadvantage missing is gas.
Well done if you got that correct.
Okay, another check for understanding before we take on our second task for today.
Can you match the term to the correct definition? The terms we have are lava, ash, gases and lahar.
The definitions we have are, magma that's erupted from a volcano, a fast flowing mix of water, ash and rocks, an abrasive mix of rocks, minerals and glass, and lastly, a dangerous mix of water vapour, carbon dioxide and sulphur dioxide.
Pause the video to match the term to the correct definition.
Okay, welcome back.
Let's see if you got those correct.
Firstly, lava is magna that has erupted from a volcano.
Ash is an abrasive mix of rock, minerals and glass.
Gases are a dangerous mix of water vapour, carbon dioxide and sulphur dioxide.
And lastly, lahar is a fast flow mix of water, ash and rocks.
Well done if you manage to match all those terms to their correct definition.
Okay, that brings us to our second task for today.
Can you make your own disadvantage cards.
On one side write the title of the disadvantage.
On the other side, explain why it's a disadvantage.
Pause the video now to complete that task.
Welcome back.
Let's have a little look.
Did you include the the following disadvantages with similar information? So my first disadvantage is ash.
It is a disadvantage because ash released from volcanoes is a hard mixture of rock, minerals and glass.
It can bury everything in its path.
My next disadvantage is gas.
It's a disadvantage because gas released from volcanoes is very harmful to the eyes, nose, throat and lungs.
My next disadvantage after that is lava.
Lava is a disadvantage because lava is a hot liquid that spills from volcanoes when they erupt.
Lava can reach up to 1,200 degrees Celsius and burns everything in its path.
And my last disadvantage is lahar.
Lahar is a disadvantage because it is a fast flowing concrete-like mixture of rock, water and ash.
It can pick up, move and carry objects in its way.
Well done if you managed to identify those four disadvantages and the reasons why they're disadvantages.
That takes us to the end of our lesson.
You've been fantastic.
Let us quickly summarise today's learning.
We have learnt that one in 20 of the world's population live close to an active volcano.
We've also learnt that advantages include the cultivation of fertile soils, income from tourism, mineral extraction and geothermal energy.
We've learnt that disadvantages include the danger posed to people and communities from the eruption of lava, lahars, poisonous gases and ash.
Well done for all your hard work today.
You've been fantastic.
I hope to see you again for some more fantastic geography.
Bye.