Lesson video

Hello, geographers.

My name's Mrs. Homagio and I'm looking forward to teaching you today.

I hope you're going to enjoy the lesson and learn lots.

Let's get started.

Today's lesson is about how we try to reduce the risks of tropical storms and we look at how we can use technology to predict them, how we can design buildings to protect us from the effects of them, and how we can educate and prepare people for the possibility of tropical storms and teach them how to keep themselves safe.

So by the end of the lesson, you'll be able to understand how monitoring, prediction, protection, and planning can reduce the effects of tropical cyclones.

There are four key words for today's lesson: forecast, meteorologist monitoring, and mitigate.

Forecast is the use of technology to predict the likelihood of a tropical storm, including its path, intensity, and speed.

Meteorologist is a person who studies the causes of weather conditions and using information from land, sea, and the atmosphere, and creates forecasts.

Monitoring is the continuous observation and recording of atmospheric conditions to detect changes.

And mitigate is taking actions to reduce the effects of a tropical storm.

There are three parts to today's lesson.

The first is what methods are used to monitor and predict.

The second, what strategies are used for protection? And the third, how can planning mitigate the impacts? Let's get started with our first section.

Meteorologists can monitor and predict tropical storms to help manage their potential impacts.

Satellites orbit the earth and take detailed images of weather patterns.

Satellites can track cloud formations, and this image here shows where a tropical storm is forming.

It's a very typical image with that rotating motion of the clouds.

Sea surface temperatures and wind shear are key factors in the formation of tropical storms. This map here shows sea surface temperatures and any anomalies from what they would expect to see.

So you can see the dark orange shows where sea surface temperatures are warmer than you would expect, and warm sea surface temperatures can lead to the formation of tropical storms. So this indicates an area where meteorologists would keep an eye on and monitor.

So meteorologists will monitor any changes to expected sea surface temperatures and wind shear that increase the likelihood of tropical storms falling.

Check for you now, true or false? Cloud formations are the only indicator of tropical storms that meteorologists monitor.

True or false? Pause the video and decide what your answer is.

Did you say false? If so, well done.

That's correct.

But why? Pause the video again and decide what made you choose false.

You might have said something like, "They also monitor sea surface temperature anomalies and wind shear as these are key factors in tropical storm formation." So they need to keep an eye on all the different conditions that lead to tropical storms forming in order to be certain of predictions or more certain of predictions that they might make.

Computer models process satellite data and other weather information to predict the storm's path, speed, and intensity.

So everything that they are observing and monitoring is fed into these computer models and they can produce these predictions.

These models help to estimate where the storm will make landfall and how powerful it will be.

And you can see on this image you've got a predicted path and speed and then direction of movement of this particular storm.

Four case, sorry, forecasts are updated regularly as the storm moves.

So you can see there the name of the tropical storm and the date when the forecast was issued.

You've got the predicted track area, so where the storm is forecast to go, potential track area for the first three days, and then day four and five.

Current location, so where the storm currently is.

And what conditions are forecast, for example, the wind speed.

So prediction and monitoring can help to reduce the effects of tropical storms. Prediction systems give people and authorities enough time to evacuate and prepare.

They can issue early warnings via social media, radios, or in-person.

Forecasting based on monitoring data and computer modelling predicts when and where a storm will hit, and this allows governments to prepare emergency services and protect vulnerable infrastructure.

It's giving them time to get ready and do what they can in order to try to stay safe, move people, and prepare buildings.

The National Hurricane Centre in the USA provides forecasts and warnings days in advance of storms, helping people to prepare.

And this image here is the hurricane evacuation route and where they can find extra information by tuning into a certain radio station.

So during Hurricane Katrina back in 2005, this advanced warning allowed many, many people to be saved as they could make these evacuations to safer areas further inland.

The challenges of monitoring and predicting.

So predictions are not always perfect.

Tropical storms can change direction or intensity very quickly, and some countries may lack the resources for effective monitoring and forecasting systems. Izzy says, "Higher income countries have better access to technology and education, so therefore the monitoring and the prediction is likely to be at a higher level and more effective." Which of these are benefits to monitoring and predicting tropical storms? Let's have a check.

Is it A, early warnings can be given out? B, tropical storms can be diverted? C, emergency services can be prepared? Pause the video and see which answer you think is correct.

If you said A and C, early warnings can be given out and emergency services can be prepared, then you were correct.

Well done.

First, sorry, onto your first task.

Let's have a look at this forecast of a hurricane, the one that we explored a little bit earlier in the lesson.

Can you use it to find answers to these questions? What is the name of the hurricane? When was the forecast issued? Where has the hurricane already made landfall? What direction is it moving in? Which coast of the USA is it predicted to make landfall on? And number six, what wind speeds are forecast for its landfall in the USA? So pause the video, use the resource, and see if you can find the answers to those six questions.

Did your answers look something like this? The name of the hurricane, Hurricane Joaquin.

When was the forecast issued? Thursday, the 1st of October, 2015.

Where has the hurricane already made landfall? The Bahamas.

What direction is it moving in? North/Northeast.

Which coast of the USA is it predicted to make landfall on? East coast.

And what wind speeds are forecast for its landfall in the USA? Between 74 and 110 miles per hour.

If you manage to extract that information from the resource, that's fantastic, well done.

Second part of the lesson says what strategies are used for protection.

So protection against tropical storms involves building design, coastal defences, which can be artificial or natural, and storm resistant infrastructure.

Investing in these protection measures can significantly reduce the damage caused by tropical storms, saving lives and limiting economic losses.

Let's have a look at the building design.

So buildings would have shatterproof glass that can reduce the risk of injury if windows break.

Materials like reinforced concrete and steel are used to make the building stronger.

Special roof designs that are sloped or tied down can prevent roofs from being blown off in the strong winds.

Storm shutters over the windows helps protect homes from flying debris and stops the windows getting broken.

And raising up buildings on pillars or stilts reduces the damage from flooding.

So these designs will help to minimise the effects that strong winds, heavy rain, and storm surges can cause.

How many of these design features are used depends on the resources, the money, and the technology available in a country.

Check for you now.

Which of these building design approaches would help protect people during a tropical storm? Is it A, using stilts to elevate the building? Use of shatterproof glass, or B? Or C, use of natural materials for building? Pause the video and see if you can work out which are correct.

Did you say A and B, using stilts to elevate the building and using shatterproof glass? If so, well done.

Andeep says, "Reinforced concrete and steel provides strength.

So in this case, natural building materials are not the ideal resource to use.

So artificial coastal defences, building flood barriers and levees and sea walls can protect coastal areas from storm surges and flooding.

So sea walls, as you can see in that image, are large barriers built along the coastline to protect against storm surges and high waves.

They can absorb the force of incoming water, reduce the risk of flooding in coastal areas.

However, they are expensive and they need to be maintained.

All of these artificial defences will cost a lot of money and have to constantly be looked after to ensure they're going to be effective.

Natural coastal defences.

So coastal ecosystems such as mangrove forests and coral reefs can act as natural barriers to storm surges and waves.

Got two images there of a mangrove forest and a coral reef.

So mangrove forests and coral reefs reduce wave energy, protect shorelines from erosion, and provide habitats for wildlife as a bonus.

And they will too absorb the energy of the waves and protect the coastal areas from damage.

Storm-resistant infrastructure.

A storm shelter is a specially designed structure built to protect people during tropical storms. We've got an image of one here in Bangladesh.

Bangladesh is a lower income country that's very low lying and it's prone to tropical storms. You can see here that it's large, so it's designed to hold a lot of people.

So it's a refuge for entire communities.

They've been built from very strong materials.

It's made out of concrete.

And it's elevated above ground.

So it's designed to be above the flood levels.

You can see there the stilts that it's built on.

And within them they'd be equipped with water, food, sanitation, and medical supplies so that people would be able to go there and feel safe and be looked after for the time during the tropical storm.

True or false? All methods of storm protection are made by humans.

Pause the video and see what you think the answer to this is.

Did you say false? If so, correct.

Well done.

But why? Pause the video again and see what you think.

You might have said something like this.

"Not all methods of storm protection are made by humans.

For example, mangrove forests are naturally occurring form of protection for coastlines from storm surges and high winds." You might also have mentioned coral reefs in the same way.

Well done.

Let's move on.

For your first task, can you describe two key features of a storm shelter and explain why each is important for the safety of the people inside? This question uses command words that you would commonly see in an exam question.

So Aisha says here, "This is an exam-style question, you have to describe and explain.

This means identify a feature and then say why it is important in protecting people." Pause the video and see if you can have a go at answering this.

So your answers might have looked something like this.

They have reinforced structures as they are built with reinforced concrete and steel.

These strong materials reduce damage from high winds and debris.

So you can see in that section of the answer, we've got a description and an explanation.

The buildings are raised up on columns like stilts to reduce damage from floods.

This keeps people safe from flooding during storm surges.

Or you might have said they are equipped with water, food, sanitation, and medical supplies.

This means people can stay safe there until the effects of the storm pass.

You might have used two of those examples there.

If you had a different one, make sure you've described and explained.

Well done.

For the third part of the lesson, we're going to look at how can planning mitigate the impacts.

So planning can mitigate the impacts of a tropical storm.

It helps communities become more resilient and reduce the loss of life and property during tropical storms. Many countries are impacted by tropical storms, but the country's level of development will affect how well they are able to mitigate the impacts.

This is due to differences in resources, technology, money, and education.

As we've mentioned previously, Bangladesh is a lower income country so its attempt to mitigate the impacts will be very different to the USA, a high income country, which is also very prone to tropical storms. Let's just check our understanding of the word mitigate.

What does mitigate the impacts of a tropical storm mean? Is it A, the formation and development of a tropical storm? Is it B, increasing the severity of a tropical storm? Or is it C, taking actions to reduce the effects of a tropical storm? Pause the video and let's see which of those you think is correct.

Did you choose C, taking actions to reduce the effects of a tropical storm? Well done if so.

That's great.

Educating the public on the dangers of tropical storms and how to stay safe is critical.

Individuals are encouraged to have a disaster kit ready should they need to evacuate.

What do you think should be in it and why? Jun says, "First aid kit in case they are injured, food and water, possibly bottled water in case water supplies are cut off, tinned food so you can keep it and it won't go off, and battery-powered radio to hear updates." Some great ideas from Jun there.

You might have had some others as well.

In Japan, a higher income country where typhoons are common, the government regularly holds disaster drills and citizens are well-informed about how to respond to storm warnings.

So in some cases, schools will perform disaster drills so that they know what to do should a tropical storm make landfall.

Authorities should have clear evacuation routes and shelters so people know where to seek safety.

And this sign here would help people to know where to go if they were trying to evacuate.

Land-use zoning can help to reduce the number of properties and businesses at risk of damage.

Areas that are vulnerable to storm surges or flooding, for example, the low-lying coastal areas, should be zoned for limited or restricted development.

So in doing that, you're stopping a lot of development happening where the damage is likely to be greatest.

Building codes set the standards for construction.

So buildings have to be designed and constructed with measures to withstand tropical storms. So stopping cheap buildings going up that'll be easily destroyed by tropical storm.

This helps people stay safe and is more sustainable.

Those buildings will last further into the future.

Conserving or protecting mangroves, coral reefs, and sand dunes as they all act as natural buffers against storms and can reduce the impact of the storms when they make landfall and reduce the size of storm surges.

So using the natural environment to help protect us as well.

It's really important.

Check for you now.

What aspects of planning for tropical storms do these images represent? Pause the video and see what you think.

Did you say, first one, emergency kits, second one, building standards or building codes, and the third one, land-use zoning.

Well done if so.

The USA and Haiti are both vulnerable to tropical storms that develop over the North Atlantic.

We can see them located on the map below.

The USA is a higher income country.

This means it has a strong economy and access to many resources.

Haiti is a lower income country.

Its economy is much weaker and many of its population live in poverty.

How these countries plan to mitigate the effects of a tropical storm will be very different.

Can you think how they may be different and why? So Laura says, "The USA will have better technology.

This means they're able to predict storms better and communicate the risk to people at risk.

The infrastructure is better so it's easier to evacuate and look after people." That's a great answer, Laura.

Well done.

And Sam, Sam says, "Haiti has fewer resources.

This means it's harder to build strong buildings and make use of technology to inform people.

So information might not reach the people who need it in time." Another great answer.

Well done, Sam.

You might have had some other ideas to contribute to that as well.

So task C, explain how planning can help to mitigate the impacts of tropical storms. In your answer, you should try to consider at least two of these ideas.

Land-use planning, building codes, education, and conservation of natural ecosystems. Pause the video and have a go.

Right, let's see how you got on.

Your answer might have looked something like this.

Land-use planning helps by restricting development in high risk areas such as low-lying coasts.

This mitigates or reduces the risk of homes and infrastructure being destroyed by storm surges or flooding.

Building codes ensure that buildings are constructed to withstand strong winds and heavy rains.

For example, building codes have, buildings, sorry, have reinforced roofs and shatter-resistant glass in windows to reduce the damage from high winds and flying debris.

This mitigates the risk of damage to buildings and people.

You may have considered some of the other ideas, but hopefully your answers were similar in their structure.

Well done.

So a lot of learning today.

Let's have a look at the summary.

Meteorologists use data, satellite imagery, and computer modelling for the prediction and monitoring of tropical storm formation.

Building design and coastal defences can help to protect communities from the impacts of tropical storms. Planning in areas that are prone to tropical storms can help mitigate the impacts.

This includes educating communities, creating clear evacuation routes and accessible shelters, and ensuring the development follows building codes and avoids high risk areas.

Well done, geographers.

I hope you have enjoyed the lesson and you have understood how we try to reduce the risks from the effects of tropical storms. I hope to see you again soon.