Lesson video

Hello, my name is Ms. Gilyeat, and I'm your Geography teacher for today.

Today's lesson is called "An introduction to the Anthropocene." Our lesson outcome for today is that you can describe the meaning of the term Anthropocene and can explain why it is debated by scientists.

We have got five keywords for today's lesson.

The first one is atmosphere, which is the layer of gases that surround Earth.

It includes the oxygen we need to breathe, so it is essential for life on Earth.

Hydrosphere includes all the water on Earth, such as oceans, rivers, lakes, glaciers, groundwater, and water vapour in the atmosphere.

Geosphere is the solid parts of Earth, including the crust, mantle, and core, as well as rocks, soil, mountains, and other landforms. And the biosphere is life on Earth, encompassing all living organisms, plants, animal, bacteria, and the ecosystems they form.

And our final keyword, which is about what our lesson is, Anthropocene is a proposed geological epoch that marks when human activity has had a significant impact on Earth.

So we've got two learning cycles.

First of all, we're going to look at the human impact on Earth's physical systems, and then we're going to look at the actual term, the Anthropocene.

So let's get going with the first learning cycle.

Now, human activities have had significant impacts on Earth's physical systems. Earth is made up of four interconnected systems that work together to support life and shape our planet.

These systems are called spheres, which are the atmosphere, the geosphere, the biosphere, and the hydrosphere.

We've just gone through what these spheres mean in the keywords, but just as a quick reminder, so the atmosphere is the gases that surround Earth.

The geosphere is the rocks on Earth and all the solid things, such as landforms, mountains, et cetera.

The biosphere is all living things, and the hydrosphere is all the water on Earth.

Okay, let's check our understanding.

Can you name the four physical systems on Earth? They are the atmosphere, the geosphere, biosphere, and hydrosphere.

Well done if got that correct.

Now, population increase has put more pressure on natural resources and speeded up environmental changes.

Population growth increases the demand for lots of different resources, including food, actual space to live and have things that we need, water, and energy, okay? So the more people there are on the planet, the more of these resources that we need.

This all puts more stress on Earth's physical systems, making them more vulnerable to breakdown and degradation.

Okay, let's check our understanding.

A rise in population has led to an increase in demand for.

Tick all that apply.

That is food, water, and energy.

Well done if you got those right.

Industrialization significantly increased the human impact on Earth's system, okay? Now, industrialization is when more people and more things were created in factories, okay? And this led to mass production of certain items. Now, alongside this, a lot of people during this period moved from the countryside to cities to work in these factories, okay? However, they weren't always very good for the environment.

So as it says there, the rise of factories and mass production led to a huge increase in fossil fuel burning.

And fossil fuels include coal, oil, and gas.

When we burn those, it releases CO2.

So yeah, as I've just said, this released large amounts of greenhouse gases like CO2, contributing to climate change.

Industrialization significantly increased the human impact on Earth's systems as well, okay? So, rivers and lakes became polluted by toxic waste, heavy metals, and chemicals.

Demand for raw materials led to mining, quarrying, altering the natural landscapes.

And industrialization drove deforestation to make ways for cities and agriculture.

So we can see here that the rivers and lakes becoming polluted has affected the hydrosphere.

Demand for raw materials led to mining, which has affected the geosphere.

And deforestation is affecting the biosphere.

Okay, let's check our understanding.

True or false? Industrialization significantly increased the human impact on Earth's systems. That is true, and can you tell me why? The rise of factories and mass production led to a huge increase in fossil fuel burning, coal, oil, and gas.

This released large amounts of greenhouse gases like CO2, contributing to climate change.

Okay, let's have a look at some of the human impacts on the different spheres in a little bit more detail.

So to start with, we're gonna think of human impacts on the atmosphere.

Now, more people means more energy use, especially from burning fossil fuels for electricity, transport, and industry.

This increases greenhouse gas emissions, contributing to climate change and extreme weather.

It also leads to air pollution, especially in urban areas.

This can affect the air quality, and poor air quality can be bad for human health.

Okay, let's have a look at human impacts on the hydrosphere.

Demand for water for drinking, farming, and industry can lead to over-extraction of rivers, lakes, and aquifers.

Increased urbanisation leads to flooding due to loss of natural drainage.

And pollution from people and industries contaminates water sources, harming ecosystems. Okay, let's have a look at human impacts on the geosphere.

More land is cleared for housing, roads, and agriculture, often through deforestation.

Increased mining and construction alter landscapes and disturb natural landforms. Now, both of these things can cause soil erosion, desertification, and the loss of fertile land.

Desertification is the process of land turning into a desert because it's getting hotter and drier.

This is quite bad for farmers 'cause it means that you can't farm on that land anymore because there's not enough, the soil isn't of good enough quality.

Okay, let's have a look, human impacts on the biosphere.

Now, habitat destruction from expanding cities and farmland reduces biodiversity.

Demand for food leads to overfishing, deforestation, and farming, disrupting ecosystems. And human-induced climate change affects plants and animal life across the globe, okay? All of those things are massively affecting all the living things on our planet.

Okay, let's check our understanding.

On the left, we have got human impacts, okay? The words on the right are the physical systems of our planet.

What I would like you to do is match the key sphere, so hydrosphere, biosphere, et cetera, with the human impact.

Okay, let's have a look.

So the first one, habitat destruction from expanding cities and farmland reduces biodiversity, that is affecting the biosphere.

Demand for water can lead to over-extraction of rivers, lakes, and aquifers, that is affecting the hydrosphere.

More energy use increases greenhouse gas emissions, contributing to climate change, effects on the atmosphere.

And increased mining and construction alters landscapes and disturbs natural landforms, that is effects on the geosphere.

Well done if you got those correct.

Okay, we're on to our first task for today's lesson.

What I would like you to do is look at the graph of population increase and CO2 in the atmosphere.

Then, I'd like to describe what the graphs show and explain the relationship between them.

Pause the video and have a go at this first task.

Okay, your second task is I'd like you to fill in the table with examples of how humans are having an impact on Earth's physical systems. Okay, let's have a look at the answers here.

So here's an example answer for the first task.

So I have put: The graph shows the population has increased by approximately 6 billion people from 1950 to present day and is expected to increase.

Annual CO2 emissions have also drastically increased from 1950.

As population increases, more people use more energy.

This relies on burning fossil fuels, which releases large amounts of greenhouse gases like CO2, contributing to climate change.

Now, you didn't have to write exactly that, but hopefully you should have something similar along those lines.

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

So, in the atmosphere, there's an increase in greenhouse gas emissions are trapped in the atmosphere, contributing to climate change and extreme weather.

For hydrosphere, pollution from people and industries contaminates water sources.

Geosphere, increased mining and construction alters landscapes and disturbs natural landforms. And for the biosphere, demands for food leads to overfishing, deforestation, and farming, disrupting ecosystems. Now, those were not the only answers that you could have put in for that task, so if you've got other ones, that is absolutely fine.

Okay, let's get on with our second learning cycle, which is looking at the term Anthropocene.

Now, Earth is approximately 4.

6 billion years old.

Earth's history can be divided into geological timescales.

Now, we are currently in, now, I do apologise if I get these pronunciations wrong, but I will have my best go, so the Phanerozoic aeon, (chuckles) the Cenozoic era, the Quaternary period, and the Holocene epoch, which began about 11,600 years ago, okay? So, we can split geological timescales into aeons, which are the largest ones, eras, periods, and then epochs, which are the smallest ones, okay? So those are the geological time periods that we are in.

Right, so, let's check our understanding of this.

Which geological period are we in? Well done if you got that right.

We're in the Quaternary period.

The other ones aren't periods of time, they are aeons and eras.

Okay, now, the Anthropocene is a proposed geological epoch, so that's the closest or the smallest period of time that we looked in those different stages, that marks the period in Earth's history during which human activity has had a significant impact on climate, ecosystems, and the planet's physical systems. The term Anthropocene comes from anthropos, which is Greek for human.

Now, there are two different proposed start dates for the Anthropocene.

No, well, there are many actually, but here are some of the main two.

So the first one that scientists have proposed is the Industrial Revolution, which was between 1750 and 1800.

And this was marked by the rise of fossil fuel use, especially coal, factories, and widespread atmospheric CO2 increase.

So this was the first period of time, really, that we were pumping CO2 into the atmosphere.

The second proposed date is the Great Acceleration, which was in 1950.

Now, this was when there was a rapid increase in human population, consumption, nuclear testing, fossil fuel use, and wide-scale environmental change, okay? So these are the two main start dates proposed for the Anthropocene epoch.

Now, the Anthropocene is characterised by these things: Rapid urbanisation, so that's more and more people living in towns and cities.

Climate change, so we're seeing more extreme weather and increased global temperatures.

Mass extinction of species.

Alteration of natural landscapes.

And widespread pollution of land, sea, and air.

Let's check our understanding.

True or false? The Anthropocene is the period of Earth's history during which Homo sapiens first evolved? That is false, and can you tell me why? The Anthropocene is a proposed geological epoch that marks the period in Earth's history during which human activity has had a significant impact on Earth.

Now, the term Anthropocene is debated among scientists, especially regarding its definition, start date, and whether it should be officially recognised as a geological epoch altogether.

I want you to have a quick chat with your partner.

What do you think? Do you think we should recognise it as a new geological epoch? Okay, let's see what Jacob has to say.

So, Jacob says, "As a scientist, I strongly believe that we are now living in the Anthropocene.

Human activity is reshaping the planet faster than any natural process.

From climate change to plastic pollution, the evidence is everywhere, even in the soil and ice! It's time we recognise this new epoch and take responsibility for our impact on Earth." Fantastic answer from Jacob there.

Let's see what Laura has to say, "I'm not convinced we should label this period the Anthropocene just yet.

Yes, humans are changing the planet, but a geological epoch needs clear evidence in the rock players that can be seen around the world.

Until we have that, it's too early to make it official." Okay, so, those are some different viewpoints on the term the Anthropocene.

Now, true or false? The term Anthropocene is widely agreed amongst scientists.

That is false, and can you tell me why? The term Anthropocene is debated among scientists, especially regarding its definition, start date, and whether it should officially be recognised as a geological epoch.

Okay, we're on to our final tasks for this lesson.

The first thing I'd like you to do is read the statements and organise them into reasons for and against the term Anthropocene in the table.

Okay, and your second task for this is I want you to put, do you agree or disagree with the statement "we are currently living in the Anthropocene epoch." Put a cross on the opinion line that we've got in the green box there.

I would then like you to explain why, okay? So why have you put yourself at that point along the opinion line? Now, you can use these sentence starters in the box below to help you out.

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

Okay, so here are the answers for against the term Anthropocene.

So changes started earlier.

Some believe human impact started thousands of years ago, not recently.

We need more proof.

There's not enough evidence in rocks yet to call this a new epoch.

There's no official recognition.

It hasn't been officially accepted as a new time period by scientists.

And these are some of the statements for.

The evidence is all around us.

Pollution, including nuclear waste, is a proof of humans' impacts.

Humans are changing Earth.

Pollution and deforestation have changed the climate.

There's been big changes since 1950.

Pollution and other human activities have accelerated worldwide changes.

So, well done if you put those in the correct column of your table.

Okay, now, this is what I have put for my answer.

So I have mostly agreed with the term the Anthropocene, or that we are currently living in the Anthropocene epoch.

However, you did not need to put where I have put for this.

This is your own opinion.

But I'll explain what I have put in my explanation: The Anthropocene is the idea that we are living in a new time period where humans are the biggest influence on Earth's systems. I mostly agree with this because humans have caused major changes to this planet, especially since the 1950s.

For example, burning fossil fuels has led to climate change, and pollution can now be seen in the air, water, and land.

Scientists have even found radioactive minerals in the ground from nuclear testing, which proves humans are leaving a mark on Earth.

Some people argue that the Anthropocene hasn't officially started or that it began earlier, like during the Industrial Revolution.

But I think the damage humans have done recently shows we are clearly in a new and different era.

Okay, so, that's my answer.

It might be worth pausing the video and seeing if you can improve your own from looking at this.

Okay, here's a summary for today's lesson.

Human activity affects Earth's physical systems. Population increase has significantly increased the human impact on Earth's physical systems. Industrialization significantly increased the human impact on Earth's systems. The Anthropocene is a term used to describe a new geological age shaped by humans.

And the term Anthropocene is debated by scientists.

Now, well done for today's lesson.

There was quite a few tricky concepts there, so fantastic job.

That's it from me, and I'll see you next time.

Bye.