Lesson video

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

In today's lesson, we are going to be learning about what our future climate is going to look like.

Okay, let's get going.

Our lesson outcome for today is that you can describe how the climate may change in the future and what the impacts of that could be.

So we have got four keywords for today's lesson.

The first one is climate model, which is a computer programme that uses maths and science to predict how Earth's climate might change in the future.

Extreme weather is a severe weather event or any weather significantly different from the average.

Food security is when people have regular access to enough safe, nutritious food to live healthy lives.

Migration is moving from one place to another with the intention of staying there.

Those key words are highlighted in bold throughout the lesson if you need to refer back to them.

We've got three learning cycles.

So first of all, we're gonna look at what temperature rise is going to happen and some of the extreme weather associated with that.

We're then going to focus on sea level rise and finally looking at the social impacts of climate change.

Okay, so let's get started with our first learning cycle, looking at temperature rise and extreme weather.

Now climate models show that Earth is likely to face rising temperatures and more extreme weather events in the future.

These changes are driven by human activity, especially the burning of fossil fuels.

So as a quick recap, fossil fuels include coal, oil, and natural gas.

When we burn those to make energy, they release greenhouse gases into the atmosphere which is contributing to our planet getting hotter.

Now in the Anthropocene where humans are the main force shaping the planet, these predictions highlight the urgent need to reduce our impact and take action to protect Earth's systems. Now the IPCC, which stands for the Intergovernmental Panel on Climate Changes, uses climate model to predict how Earth's climate may change.

They show that if we continue to burn fossil fuels, global temperatures could rise by more than two degrees Celsius by the end of the century.

So if we have a look at the slide here, on the right, we have a graph which shows different predictions of what our climate is going to look like.

Okay.

So on the x-axis we've got time.

So this is a prediction from 2000 to 2100, so looking into the future.

And on the y-axis we've got the amount of CO2 in the atmosphere, which is measured in PPM, which starts with parts per million.

Now, those different lines on the graph represent different predictions.

Okay.

So, the first one we're going to look at is RCP 2.

6, which is the most optimistic prediction, let's say.

So if we have a look at the purple box, we've got a description of what that is there.

So this is a low emission scenario where the world takes strong action to cut greenhouse gases.

Global warming stays below two degrees Celsius, and this is the most optimistic pathway.

So if we can, that would be the one that we want to aim for the most.

Okay.

The next prediction from a different model is the RCP 4.

5.

Now, this is a medium emission scenario where some action is taken.

Emissions peak around the mid-century, and then they start to decline, and warming is moderate.

So it's likely to be between two and three degrees C.

The next model is called the RCP 6.

0.

Okay.

Again, this is another medium emission scenario where some action is taken.

Emissions peak around 2060, and then they decline.

Warming is moderate likely between 2.

5 to 3 degrees C by 2100.

Now, the worst prediction and the worst kind of climate model, which we really, really don't want to happen, is the RCP 8.

5.

This is a high emission scenario where emissions continue to rise.

This leads to the most severe global warming, possibly over four degrees Celsius, causing major climate impacts.

Okay.

So these are different models which predicts what's going to happen in the future.

And ideally, we would like to get to the RCP 2.

6 model.

Okay, let's check our understanding.

What does that graph show? You could either write it in your book or you can have a quick chat with your partner.

Okay, so the graph shows global temperature increase in the century based on different climate models.

This one uses greenhouse gas emissions.

So it's looking at CO2 in the atmosphere.

Now, extreme weather events are becoming more frequent and more intense, causing significant economic and social impacts for people across the world.

Okay.

So we can see here we've got a bar chart with number of extreme events increasing basically over time.

So this isn't a prediction.

This is what has happened already from 1980 to 2015.

Now, the different colours represent different types events.

So, the orange ones are geophysical events.

The kind of turquoisey colours are meteorological events.

The blue is hydrological events, and the orangey colour is a climatological event.

Quite hard word to say, that one.

Okay, so geophysical events, so these are the purple ones, include Earth movements such as earthquake, tsunamis, and volcanic action.

And we can see there that on the bar chart that they state relatively the same kind of amounts over the year.

There's potentially a slight increase, okay, but they are a small proportion of all extreme events.

They have increased very slightly, but in general, they stay quite the same.

Okay.

The next one are meteorological events, and these include things like storms, hurricanes, things like that.

Okay.

We can see over time that there has been an increase in meteorological events.

Okay.

And they do hold quite a proportion of overall events.

The blue ones are hydrological events such as floods.

So this is extreme weather to do with water basically, and we can see that there is a definite increase in the amount of these events over time.

And finally, climatological events are longer term climate events such as extreme temperature, drought, and wildfires.

And again, over time, there has been an increase in those types of extreme weather.

So, overall, we can see that there is an increase in frequency of nearly all the types of events apart from geophysical ones.

Now, of all the extreme weather events in 2024, 74% were more likely or more severe due to climate change.

9% were less likely or less severe.

And overall, 83% were influenced by human-caused climate change.

So if we have a look at the slide here, we've got a world map, and the circles show the proportion or the number of extreme weather events in those different continents.

So we can see, for example, that Europe had 116 events that were more severe or more likely due to climate change.

Okay.

So overall, globally, they are becoming more severe due to climate change.

Okay, let's check our understanding.

In 2024, climate change did not affect extreme weather events.

That is false, and can you tell me why? Overall, 83% of the extreme weather events in 2024 were affected by climate change? 74% were made more severe or more likely, and 9% were made less likely or less severe.

Well done if you got that right.

Now, different parts of the world will experience different types of extreme weather.

Some places will experience stronger storms and heavier rainfall.

Some will experience powerful heat waves and longer droughts, and some places will experience more wildfires.

Okay, so different parts of the world aren't going to experience the same thing.

Okay.

Some places may see more floods, and some places may see more droughts, okay, depending on where in the world you are, and there are lots of different things which can influence this.

The 2019, 2020 bushfire season in Australia, known as the Black Summer, saw wildfires across the country fueled by extreme heat and prolonged drought.

Over 18 million hectares burned, devastating forests and wildlife habitats.

Around 3 billion animals were affected, reducing biodiversity.

And particular emissions from burning vegetation reduced air quality in the area.

Burned areas suffered increased erosion, degrading soil, and water quality.

Okay.

So these wildfires didn't just affect the people that were living there, but they had a massive impact on the ecosystem.

And you can see in the picture there, there's a firefighter in one of the areas that was affected.

So you can see how horrendous it would be to be where there is a wildfire.

Now, extreme weather is damaging ecosystems, destroying homes, and disrupting lives.

Clear signs of how human-driven climate change is reshaping the planet in the Anthropocene.

For example, more intense storms can pollute rivers, erode soil, knock down trees, destroy habitats, and damaged coastal ecosystems. We've got on the slide here an image of the flooding caused by Hurricane Harvey in Texas in 2017.

Now, obviously, that is going to have massive social impacts.

People are going to lose their homes, businesses.

Okay.

However, people often forget about the environmental impacts of that as well, which can last for a very, very long time after the event.

Okay, let's check what we've learned so far.

Can you give three examples of extreme weather that are more likely due to climate change? So, you could have had stronger storms and heavier rainfall, powerful heat waves, and longer droughts or more wildfires.

Well done if you got those right.

Okay, we're onto our first tasks for the lesson.

First of all, what I'd like you to do is look at the graph that we looked at earlier and describe what the graph shows.

Secondly, I'd like you to look at this image and annotate the photograph with environmental effects.

Okay, let's have a look at some answers.

So my description of the graph is that the graph shows an overall increase in the frequency of extreme weather events, while geophysical events remain relatively steady.

Meteorological and hydrological events have risen the most and make up the majority of all recorded extreme events.

So well done If you have got something similar to what I have put.

Okay, so annotations that I've got of the wildfire.

So we've got smoke causes the air pollution, trees and vegetation are destroyed by the wildfire.

Animal habitats have been destroyed and wildlife is likely to have been killed as well.

Okay, we're on to our second learning cycle, which is looking at sea level rise.

Now, ice in polar regions is melting rapidly.

Arctic Sea ice has been monitored by satellites for the past 46 years, and they have observed persistent trends of more melting in the summer and less ice formation in the winter.

In 2024, the area of Arctic Sea ice shrank almost 2 million kilometres squared below the average area for 1981 to 2010.

So if you have a look at the image that we've got on here, which is a satellite image, the yellow line represents the average amount of ice expansion in 1981 to 2010.

Okay.

But we can see there that actually the ice area that is covered, there's a lot less of it.

Okay.

Now, monitoring sea ice changes has revealed wide ranging impacts on arctic ecosystems, including losses and changes in polar wildlife habitat.

This is threatening species like polar bears who rely on the sea ice for hunting.

Now, melting sea ice does not directly contribute to sea level rise as the water in the ice form is already in the sea.

Much like a melting ice cube in a drink doesn't cause the drink level to rise, okay? Because the ice is floating in the sea, when the ice melts, it's already there, so it doesn't contribute to the actual rise.

However, sea ice reflects the sun's radiation protecting the sea from the heat.

Okay, so because sea ice is white, the colour of the white reflects the heat back out into the atmosphere.

Now as the sea ice melts, it exposes the sea to sun's radiation, contributing to ocean warming, which in turn contributes to sea level rise.

Okay? So if you imagine there was an area that was covered in white ice, which reflects some of the sun's heat, that ice has now melted.

You've got a dark blue ocean which absorbs heat that leads to the ocean water getting warmer 'cause it's absorbing more of the sun's heat.

And that in turn leads to more sea level rise.

Now, the warming of oceans causes sea water to expand, contributing to sea level rise through thermal expansion.

Melting ice sheets and glaciers, particularly in Greenland and Antarctica, release large volumes of water into the oceans, further raising sea levels.

Okay.

So we've got a world map on the board here, and we can see that the different colours represents where there has been sea level change.

So the darker the red colour shows an increase in the sea level of that area.

So you can see that some areas particularly in the Arctic are seeing quite an increase in the sea level and especially also on the East Coast of America.

Now, this will have global effects with low-lying coastal areas and islands the most vulnerable.

Okay, let's check our understanding.

True or false? The environmental effects of climate change are affecting the survival of polar bears.

That is true, And can you tell me why? Arctic sea ice is declining due to global warming.

Polar bears use the sea ice for hunting, therefore it is harder for them to feed themselves and their young.

Well done if you got that right.

Now, low-lying areas such as Bangladesh and small islands, for example, Tuvalu, are at risk of being submerged.

That means that they're being covered with water.

Okay.

So if we have a look at the map that I've got here, we've got the country of Bangladesh.

Now, the colour that has been shaded in shows the elevation above sea level.

So you can see that nearly half of the country is less than 10 metres above sea level.

With a good chunk of the country being less than seven metres above sea level.

Those areas are very vulnerable to sea level rise, because if the water rises, then that's going to cover quite a chunk of that land.

Now, higher sea levels lead to faster erosion of cliffs and beaches as well.

Habitats can be destroyed and species lost as wetlands, mangroves, and salt marshes are lost to coastal flooding and erosion.

Sea water can move into rivers and underground water supplies called salt water intrusion.

So that fresh water that's in the river or the groundwater mixes with the salty water, and then it's turned salty.

This makes the water too salty for drinking and harms fresh water ecosystems. Okay.

In areas like Bangladesh, they do a lot of farming, so the crops there can suffer as well because they can't grow in salty water.

Now, some areas are actually choosing to grow plants that can grow in salty water.

So they're having to manage and diversify to deal with this impact of salt water intrusion.

Okay, we're onto our first, sorry, second task for this lesson.

So what I would like you to do is have a look at that flow diagram, and see if you can put the following statements into the correct part of the diagram.

Pause the video and have a go.

Okay, here are the answers.

So we've got global temperature increase at the top, and that's leading to the warming of oceans causing sea water to expand and polar ice in the Arctic and Antarctic melting.

Both those things together can create sea level rise, which can lead to salt water intrusion, which affects ecosystems, faster erosion of cliffs and beaches, and habitats destroyed and species loss.

So well done if you've got those.

Okay, finally, for this lesson, we're going to look at the social impacts, so how these things are going to affect us as humans.

Okay, so there are lots of different ways that climate change is going to affect people, and now here are some of them.

There's gonna be the economic impact of extreme weather events.

If you imagine if you have a tropical storm or a flood, there's the cost of rebuilding, there's the cost of businesses going under.

Health impacts.

Okay.

Displacement of populations, that's people having to leave their homes.

Conflict over the resources, and also threats to food security.

So that's enough food available for the people that live there.

Now, climate change can lead to conflict by putting pressure on vital resources, like water, food, and land.

As droughts, floods, and extreme weather events become more common, some communities may struggle to survive.

Okay.

So as these resource is becoming less available, people tensions can rise up basically.

So this can lead to tensions between groups or even countries, especially where resources are already scarce.

Now, in the Sahel region of Africa, rising temperatures and frequent rounds have made it harder for farmers and herders to find water and grow food.

This has led to competition over land and resources, increasing tensions between communities.

In some areas, these environmental stresses have added to existing conflicts and made them worse.

So the area that's shaded on there is the Sahel, which used to be a really good farmland area.

It used to have, yeah, good soil for growing crops.

But as you can see in the picture, a lot of the area is turning to desert, which means there's not enough water and people can't grow crops anymore.

So resources are becoming more scarce.

Okay, can you answer this question? How can climate change lead to conflict? So we've got an answer from Jacob here.

"Climate change can lead to conflict by putting pressure on vital resources like water, food, and land.

This can lead to tensions between groups or even countries, especially where resources are already scarce." Spot on, Jacob, well done.

Now, climate change is forcing more people to leave their homes.

Extreme weather is making some places unlivable.

Families may lose their homes, farmland, or access to clean water, pushing them to move within their country or across into a different country.

Now, in the Anthropocene where human activity is changing the planet, climate-related migration is becoming a major global challenge.

So we're going to have to think where a lot of the people that can't live where they are from, because it's becoming unlivable, where those people are going to go, and how we are going to settle them into their new homes.

Now, in 2020, 30 to 40 million people were displaced due to climate events such as sea level rise, floods, and storms. So already, over the world, we are seeing people having to flee their homes because of the impacts of climate change.

Now, Tuvalu is a Pacific island nation.

It has an average height of just two metres above sea level, making it very vulnerable to rising sea levels.

So we can see the location of Tuvalu northwest of Australia in the Pacific Ocean.

In recent years, 80% of Tuvalu's land has experienced flooding, and salt water intrusion has damaged crops, threatening food security.

Many Tuvaluans have been forced to migrate with over 4,000 already resettling in New Zealand.

They can't live there anymore because it's becoming submerged or they can't grow crops.

So New Zealand has taken a few of those people in.

Okay, let's check what we've learned.

How can climate change lead to migration? We've got an answer from Laura here.

"So climate change is forcing more people to leave their homes.

Extreme weather is making some places unlivable.

Families may lose their homes, farmland, or access to clean water, pushing them to move within their country or across borders." Okay, we're on to our final task for this lesson.

What I'd like you to do is annotate the world map to show the effects of climate change on people and the environment in specific regions.

Now you can use examples provided in this lesson, but you may want to research or you may know some of your own already.

I'd like to try and get at least three examples on your world map.

So pause the video and have a go at this final task.

Okay, here are some of my annotations.

So increased temperatures and prolonged droughts have affected food security in Sub-Saharan Africa.

Rising sea levels are displacing people in low-lying coastal areas and small islands, for example, in Tuvalu and Bangladesh.

And melting of ice in the Arctic is affecting species who use it for hunting and breeding, for example, polar bears and seals.

Okay, well done if you've got some great examples onto your map.

So we've got a summary of today's lesson.

Climate models predict rising temperatures and more extreme weather.

Sea levels are expected to rise due to melting ice and thermal expansion.

Some regions may face drought while others experience more flooding.

Climate change may increase migration and conflict over resources.

And actions taken now will influence how severe future climate change becomes.

Now that's it from me today.

Well done on this lesson, and I'll see you next time.

Bye.