Hello, my name is Mr. March, and I'm here today to teach you all about reducing risks from earthquakes and volcanoes.

So grab everything that you need for today's lesson and let's get going.

So by the end of today's lesson, you will be able to explain why people continue to live in areas at risk from tectonic hazard and how management can reduce the effects of a tectonic hazard.

There are three key terms for today's lesson.

Those are hazard risk, management, and monitoring.

Hazard risk refers to the likelihood or chance of being affected by a natural hazard such as an earthquake or volcanic eruption.

Management refers to techniques used to reduce hazard risk, including monitoring, and prediction, and planning, and preparation.

And finally, monitoring refers to techniques used to detect and record indicators of earthquakes and volcanic eruptions.

There are two learning cycles for today's lesson.

I'm gonna start with learning cycle one, which is why do people live where tectonic risk is high? Now if we look at the satellite image in front of you, what tectonic hazard can you identify? You may like to pause the video here whilst you look through that image and try to identify the tectonic hazard.

Well, here is that tectonic hazard.

And as Andeep correctly says, this feature looks like a volcano.

I think I can see a crater.

And as I said, Andeep is absolutely spot on.

And we're now gonna look at this volcano in a little bit more detail.

And just looking at the satellite image from above a little bit more, we can see that there are settlements around this volcano.

And so we're gonna try to understand why it is that people live where the tectonic risk is so high.

This volcano then is called Vesuvius, Mount Vesuvius.

It's located in central Italy.

And it last erupted during the Second World War in 1944.

Approximately 3 million people live near Mount Vesuvius, including nearly 1 million people in the city of Naples.

And we can see that on this 3D satellite image that you can see on the screen in front of you.

We can see Mount Vesuvius towering high behind the city of Naples, where 1 million people reside.

So why is it then that people live so near an active volcano? You may like to pause the video here whilst you consider your own answer to that question or perhaps even discuss it with someone near you.

There are a range of reasons why people continue to live in areas at risk of tectonic hazards.

And we can break these down into four main categories, economic opportunities, risk perception, disaster preparedness, and lack of alternative places to live.

Economic opportunities are for reasons such as fertile soils.

Volcanic eruptions produce, over time, very fertile soils which make excellent farmland.

That is one key reason why the area around Vesuvius has been so densely populated since Roman times and before.

Risk perception is also important.

A long time in human terms can pass between hazard events, especially between disaster level events.

And people can assume that the hazard will not affect them in their lifetimes.

Even when people have experienced a hazard, they may feel that since they survived it once, they can survive it again, or perhaps that now it has happened, it is not likely to happen again.

Disaster preparedness can mean that people feel protected from hazard risks.

They trust the early warning systems and they trust the evacuation procedures.

They trust that the building they live or work in will withstand the hazard, and they're insured against financial losses from a hazard event.

And people may just not have any alternative.

People may be too poor to relocate or too poor to live anywhere but in the high risk areas, for example, on steeply sloping land on the outskirts of a city, or there may not be other places to live, such as on volcanic islands, for example.

Where cities have grown up in areas at risk of tectonic hazards, then there is just too much invested in the settlement for it to be moved.

Imagine moving all of the operations and functions of a city like San Francisco or Tokyo.

These four categories can be linked as well, of course.

And in particular, risk perception will be strongly affected by people's confidence in disaster preparedness.

So a quick learning check, and it says people living near a volcano say they feel safe as it hasn't erupted since 1944.

What category of reasons would that go into? So what I'd like you to do then is pause the video here whilst you read through those four options and decide what you think is the correct answer.

And the correct answer was d, risk perception.

So really, really well done if you're able to identify that as the correct answer.

Our second learning check says the government in an area with a high hazard risk has set up evacuation routes for residents.

What category would this go into? So once again, I'd like you to pause the video here whilst you read through those four options and then decide what you think is the correct answer.

And the correct answers were b and d.

B, disaster preparedness, and d, risk perception.

So really, really well done if you're able to identify B or D as the correct answer.

So our final learning check says, why do you think people have always lived near Vesuvius? Now, once again, I'd like you to pause the video here whilst you try to recall that piece of information.

And the correct answers were fertile volcanic soils and economic opportunities.

Really, really well done if you're able to recall that piece of information.

So we have two practise tasks for learning cycle one.

And the first practise task says these GIS layers show city population, orange proportional circles, plus recent earthquake magnitude, the red proportional circles.

Now the question is suggests two reasons why so many people continue to live in Tokyo, Japan when this city experiences frequent earthquakes.

The second practise task says the photo on the left shows housing in Port-au-Prince, Haiti, which is the capital city of Haiti, today, while the photo on the right shows housing in Port-au-Prince after an earthquake in 2010.

I would like you to suggest two reasons why people continue to live in the same places and in the same housing type despite the earthquake hazard risk.

So what I'd like you to do then is pause the video here whilst you attempt these two practise tasks.

Best of luck Time now for some feedback.

So the first question said to suggest two reasons why so many people continue to live in Tokyo, Japan when this city experiences frequent earthquakes.

Now your answer may have included something like this.

Disaster preparedness could be one reason.

The government could have invested in earthquake-resistant buildings and evacuation plans.

A second reason could be that a city like Tokyo is so large and important that it would probably be very difficult for people to find the same opportunities elsewhere.

The second question said to suggest two reasons why people continue to live in the same place and in the same housing type despite the earthquake hazard risk.

Now, once again, your answer may have included the following.

Well, a lack of alternatives is likely to be one reason because these are houses built by poor people, possibly in areas that are cheap enough, because they're on steep slopes, for them to afford.

A second reason could be to do with risk perception.

Perhaps people, they feel they have always survived earthquakes before, so they can do so again.

Really, really well done if you're able to include anything like that in your own answer.

We're on now to our second and final learning cycle, and this is all about how can management reduce tectonic hazard risk? Well, the management of hazard risk can be broken down into four different areas.

The first area is monitoring, looking out for signs that a tectonic hazard is about to happen.

So trying to gain knowledge and understanding about when a tectonic hazard may actually occur is the first step.

With that then, we can predict, using monitoring data and records of past events to forecast when a tectonic hazard will occur.

Now this is a really important step.

Being able to predict when it will happen or where it will happen is a key bit of information.

We can then use that type of information to help us with protection, designing buildings and infrastructure that is resilient to hazard impacts.

And finally, planning, preparing ways to reduce hazard risks, such as training emergency services and organising evacuation shelters.

So a quick learning check.

It says, which of the following types of hazard management would building earthquake-resistant buildings come under? And you can see you have four options there.

So what I'd like you to do then is pause the video whilst you read through those four options and then select your answer.

And the correct answer was c, protection.

Really, really well done if you're able to identify c as the correct answer.

The second learning check says to complete the missing types of hazard risk management from the diagram you can see below.

You can see that there are three gaps missing.

What I need you to do then is pause the video here whilst you try to recall the pieces of information to fill those three gaps.

And the correct answers were monitoring, prediction, and planning.

Really, really well done if you're able to recall those pieces of information.

So let's start with how we can actually monitor volcanic activities, and there are four different ways that we need to know about.

The first one is measuring the seismic waves because the movement of magma can produce earthquakes and therefore we can pick up on those quakes in the earth by looking at these seismic waves using something called a seismometer.

Now, frequent shallow tremors suggest that magma is rising and therefore perhaps that a volcanic eruption is on its way.

The second then is ground deformation.

Well, rising magma causes the ground to swell, so we can actually see the ground swelling and see that ground deformation.

So we can use GPS and we can see, use, rather, tiltmeters as well to identify that changes in the land.

Although the changes may be small, these instruments are very sensitive and can pick up on those minute changes.

The next then is gas emissions.

And gases are emitted when an eruption is imminent.

So we can use gas sensors and we can use spectrometers.

And the increase in sulphur dioxide emissions means that rising magma is happening and once again is a key indicator of a possible volcanic eruption.

The fourth and final one then is thermal imaging.

So rising magma increases ground temperatures.

And so we can use a thermal camera to pick up on those changes.

Now heat changes in lava lakes and vents then can all indicate a possible volcanic eruption in the near future.

In terms of monitoring earthquakes then, seismometers measure the seismic waves raised by earthquakes, and seismographs plot those vibrations.

Global networks of seismographs identify the location and magnitude, or strength, of those earthquakes.

GPS networks measure small movements in Earth's crust, which may indicate stress is building up.

And finally, strainmeters measure the stress and pressure at faults in the crust.

Increased stress may indicate a potential earthquake.

So time now for a quick learning check, and it says, which of the following are instruments that can be used to monitor earthquakes, as well as volcanoes? So you have four options on the screen in front of you.

What I want you to do then is pause the video here whilst you read through four options, and select all answers that you think apply to this question.

Best of luck.

And the correct answers were b, GPS, and c, seismometer.

Really, really well done if you're able to identify b and c as the correct answer.

So monitoring is really, really important because it allows us to gather data that we can then use to predict where or perhaps when a volcanic eruption or indeed earthquake may actually occur.

So warning signs make it possible to predict a volcanic eruption perhaps weeks or even months in advance of when it actually happens.

Now what signs might those be? Well, as Izzy says, these signs can be lots of shallow earthquakes, ground swelling, gas emissions, and temperature rises.

This though isn't the case for earthquakes.

They're much more difficult to predict.

Measurements of stress building up give a long-term indication of increased earthquake risk, but there are no reliable short-term indicators that an earthquake is about to actually happen.

So a quick learning check, it says true or false.

Because we know the location of plate margins, scientists can predict when earthquakes will happen.

What I need you to do then is pause video here whilst you consider your answer to that statement.

And the correct answer was false.

Now, once again, I'd like you to pause the video whilst you consider as to why the statement is false.

And the reason it's false is, well, because while scientists can identify areas that are at high risk of earthquakes, exact predictions for when and where an earthquake will occur or what magnitude, or strength, it will be are simply not possible.

So really, really well done if you're able to identify those two correct answers.

So how can we protect ourselves from volcanic eruptions? Well, the first thing we can do is that we can actually channel lava away from settlements, for example.

So lava, we know, is very destructive, but channels and walls can be constructed to actually divert or change the direction of these lava flows away from people and settlements.

Buildings can also be strengthened so that their roofs can bear a greater weight of falling ash without those roofs collapsing and potentially killing or injuring those people inside.

Evacuation shelters can be constructed and constructed in areas at lower risk of lahars, lava flows, and pyroclastic flows, once again trying to protect people.

And finally, ventilation systems that can be sealed to block out ash as well.

So how can we protect ourselves from earthquakes? Well, we can build earthquake-resistant buildings which have shock absorbers at their base to absorb those seismic waves, as we can see on the diagram in front of you.

Those buildings can also be built with strengthened frames which can move with the ground shaking.

We can also ensure that they're built with strict building codes which prevent building in high risk areas and ensure buildings are strongly constructed.

Refuge parks and cities, large open areas where people will be safe from building debris and falling debris from those buildings which may be slightly damaged during the earthquake.

And finally, gas shut off valves that automatically cut off gas flow when the pipes break due to the shaking of the earth.

This is really key since it can actually prevent fires from breaking out across the city.

What about protection from tsunamis? And remember, tsunamis are a secondary hazard caused by an earthquake.

Well, sea walls safeguard coastal settlements and infrastructure from tsunamis if they're constructed high enough, and that is absolutely key in protecting settlements, for example.

Evacuation shelters can be built on high land so that people can escape tsunami flooding.

Mangroves can be planted, which helps absorb the force of those incoming tsunami waves.

We can see this being done on the image in front of you.

And finally, buildings can be raised on stilts to reduce damage from flooding.

Time now for a learning check.

It says match the hazard to the method of protection from that hazard.

So on the left-hand side, you can see you've got the hazard type, and on the right-hand side, you've got the method of protection.

What you need to do then is match those two together.

So pause the video here whilst you attempt this learning check.

And these are the answers that you needed to have got.

So lava flows matches with channels and walls to divert flows away from settlements.

Tsunamis matches with sea walls.

Ground shaking matches with earthquake-resistant buildings.

Ash in the air matches with sealable ventilation systems. And finally, ash buildup matches with reinforced roofs.

Really, really well done if you're able to identify those correct answers.

So we're now to planning.

How can planning be used to reduce hazard risk? Well, short-term relief is our first option.

For example, stocking up on emergency supplies, such as food and water, as well as those emergency shelters to provide that key critical emergency relief at the hours or days after the tectonic hazard.

Second then, training and resourcing emergency services.

Yes, ensuring that the emergency services are properly trained and equipped in order to be able to carry out those perhaps search and rescue efforts in the immediate days after the tectonic hazard.

The third then is educating people about how to prepare and react to hazards.

This is about giving training to people in schools or workplaces about how to react to perhaps an earthquake, about perhaps teaching them that they need to get underneath perhaps a desk or something with a hard surface so that they can protect their heads and their bodies from falling debris.

And this may be the difference between life and death.

The fourth then is investing in early warning systems and upgrading them.

Again, trying to give people as much advanced knowledge about this incoming tectonic hazard, be it a tsunami, a volcanic eruption, or indeed an earthquake.

Next then, developing and publicising evacuation routes so that people know where they need to go, where their nearest evacuation shelter is, what they need need to do, where's the nearest high land that they they need to get to, and drilling them on it as well.

Using data then from past events to map hazard risk and then use these maps to plan development.

For example, no new development in high risk areas.

This is one way that we can actually plan to protect people.

Although it's not possible to predict earthquakes, early warning systems are in fact possible.

And this can give people a few crucial minutes to prepare.

How is this though? Well, earthquakes release something called P-waves first.

And these are fast-moving but less destructive waves.

Seismometers then can detect these P-waves and set off warning systems, which can be linked to perhaps people's phones.

And these can be automatic alerts which warn people about a forthcoming earthquake.

The S-waves follow, and these are much more slow but are more destructive.

So by being able to detect these P-waves, it can give people a few crucial minutes to prepare.

If people know what to do, hazard risks can be lowered even if there are only a few seconds of warning.

For example, we can do a method called the drop, cover, and hold on.

And this then, as you can see on the image in front of you, can protect people from falling debris by ducking under a table.

Planning therefore involves regular practise so that everyone knows how to react to reduce their risk of death or injury.

So a quick learning check.

It says true or false.

Because it's not possible to predict exactly when an earthquake will occur, early warning systems do not work for earthquakes.

So you need to pause the video here whilst you consider as to whether that statement is true or false.

And the correct answer was false.

Now, once again, I'd like you to pause the video whilst you consider as to why the statement is false.

And the reason it's false is, well, earthquakes release two different types of seismic wave.

P-waves are released first.

These travel fastest but are much less destructive than the slower moving S-waves, which are released second.

The gap between the P-waves and the S-waves means there is time for an early warning system to alert people about the earthquake, although this may only be a few minutes or even seconds of warning.

Really, really well done if you're able to identify those two correct answers.

So we're on now to our two practise tasks for our final learning cycle.

And the first practise task says, this GIS layer uses data about past lava flows on Hawaii island to map hazard risk for future eruptions.

How could this information be used to manage volcanic hazards on Hawaii? The second practise task says, explain two ways in which planning could reduce earthquake hazard risk in Port-au-Prince, Haiti, an LIC, or developing country.

So what I'd like you to do then is pause the video here whilst you attempt these two practise tasks.

Best of luck.

And now for some feedback for the first practise question.

And your answer may have included the following.

Management of volcanic hazards is about reducing hazard risk and this GIS layer could be used in planning where existing buildings might need additional protection, for example channels and walls to divert lava flows.

The information could also be used for new development, making sure that this takes place in lower risk areas and not in high risk zones.

And the information could be used to plan evacuation routes and evacuation shelters, which need to lead people away from higher risk zones to the safest areas.

And for the second question, your answer may have included the following.

One planning option could be educating people about how to prepare and react to hazards.

This is effective because if everyone knows what to do to protect themselves and where to go to stay safe, then this could save many lives.

It is also quite low cost, which would probably be important for an LIC.

A second way would be to plan and publicise evacuation routes.

Cities are densely populated, so there needs to be an organised set of routes to get lots of people out of danger areas as quickly as possible.

Signs to tell people about these routes would probably be not too expensive to instal either.

So really, really well done if you're able to include anything like that in your own answer.

Time now for our learning summary.

And what do we need to know from today's lesson? Well, people continue to live in areas at risk from tectonic hazards for many, many different reasons, including economic opportunities, as well as how people actually perceive hazard risk.

Monitoring and prediction can reduce the risks from a tectonic hazard, although there is no way currently to reliably predict when an earthquake will occur.

Protection and planning can reduce hazard risk, for example through earthquake-resistant buildings or mapping zones of hazard risk.

So really, really well done during today's lesson.

It was a pleasure teaching you.

And I will see you again on the next lesson.

Goodbye.