What is climate change? - The Climate Question, BBC World Service

Summary

In this episode of 'The Climate Question' podcast, host Jordan Dunbar explores the concept of climate change with experts Dr. Rose Mutiso, Dr. Zeke Hausfather, and climate scientist Adam Levy. They discuss the greenhouse effect, the impact of human activities on global temperatures, and the consequences of a warming planet, including extreme weather events and sea-level rise. The conversation also touches on the importance of transitioning to renewable energy sources and the role of individual and political action in combating climate change.

Takeaways

• 🌍 Climate change refers to the addition of heat to the Earth's system, primarily due to human activities such as burning fossil fuels and deforestation.
• 🌡️ Greenhouse gases, including carbon dioxide, trap the sun's heat in the atmosphere, leading to a warmer Earth surface—a phenomenon known as the greenhouse effect.
• 🔥 The increase in greenhouse gases is due to human activities, which have significantly amplified the natural levels, causing more heat to be trapped.
• 🏙️ The energy sector, particularly the burning of fossil fuels for electricity, heat, and transportation, is a major contributor to carbon dioxide emissions.
• 🌡️ Global warming leads to more extreme weather events, including heatwaves, floods, droughts, and wildfires, which are already affecting various regions around the world.
• 💧 A warmer atmosphere can hold more water, leading to heavier rainfall and increased flooding during downpours.
• 🌊 Rising sea levels are caused by thermal expansion of warming oceans and the melting of ice sheets, which can displace coastal and island communities.
• 🔥 Drought conditions can exacerbate wildfires, as hotter and drier vegetation provides more fuel for fires to spread rapidly.
• 🌿 Climate change impacts are global, with potential long-term effects on habitability, agriculture, and the need for significant adaptation and mitigation efforts.
• ♻️ Transitioning to cleaner and more efficient energy sources, such as solar and wind power, and adopting electric vehicles can help reduce reliance on fossil fuels and mitigate climate change.

Q & A

What is the primary focus of The Climate Question podcast?

The Climate Question podcast, hosted by Jordan Dunbar, focuses on discussing the biggest issues related to climate change with experts, activists, businesses, and reporters from around the world.

What is the greenhouse effect and how does it relate to climate change?

The greenhouse effect is a natural process where certain gases in the Earth's atmosphere trap heat from the sun, keeping the planet warm enough to sustain life. However, human activities, such as burning fossil fuels and deforestation, have increased the concentration of these greenhouse gases, leading to more heat being trapped and causing global temperatures to rise, which is the essence of climate change.

Why is carbon dioxide considered a greenhouse gas?

Carbon dioxide is considered a greenhouse gas because it has the ability to trap heat in the Earth's atmosphere. When humans burn fossil fuels or cut down forests, carbon dioxide levels increase, enhancing the greenhouse effect and contributing to global warming.

How does the burning of fossil fuels contribute to climate change?

Burning fossil fuels releases carbon dioxide as a byproduct. This increase in carbon dioxide adds to the greenhouse effect, trapping more heat in the atmosphere and leading to a rise in global temperatures, which is a key aspect of climate change.

What are some of the direct effects of the world getting hotter mentioned in the podcast?

Some direct effects of the world getting hotter include making already hot places even hotter, leading to difficulty in living conditions, and turbocharging extreme weather events such as heatwaves, floods, droughts, and wildfires.

How does a hotter atmosphere contribute to more intense rainfall and floods?

A hotter atmosphere can hold more water, acting like a more effective sponge. This results in more water being available in the atmosphere during heavy downpour events, leading to increased intensity of rainfall and potential flooding.

What factors are driving the rise in sea levels due to climate change?

The rise in sea levels is driven by two main factors: thermal expansion, where warming ocean water takes up more space, and the melting of ice sheets, particularly in Greenland and parts of Antarctica, which flow faster into the oceans.

Why are some regions experiencing more drought as a result of climate change?

Climate change can cause some regions to experience more drought because it alters weather patterns and leads to the redistribution of water. Hotter and drier conditions can result in vegetation losing moisture, making it easier for fires to start and spread.

How can individuals make a difference in combating climate change?

Individuals can make a difference by getting engaged in politics, voting for leaders who prioritize climate action, and making lifestyle changes that reduce their carbon footprint, such as using renewable energy, adopting energy-efficient practices, and supporting policies that combat climate change.

What technological advancements are mentioned in the podcast that could help mitigate climate change?

The podcast mentions the significant drop in cost and increased efficiency of renewable energy sources like solar and wind power, as well as the rise of electric vehicles and innovations in urban planning that reduce the need for driving.

Why is it important to continue fighting climate change even if some impacts are already being felt?

It's important to continue fighting climate change because every degree of warming matters, and the impacts get progressively worse with more warming. Even if some impacts are already being felt, it's crucial to prevent further damage and limit the extent of climate change.

Outlines

00:00

🎙️ Introduction to The Climate Question

The first paragraph introduces the podcast *The Climate Question*, hosted by Jordan Dunbar from the BBC World Service. It highlights the diverse range of contributors including experts, activists, and businesses, discussing climate change. Jordan sets the tone by describing an exciting scenario atop a reactor, and humorously notes a sea creature encounter. The main theme of the episode revolves around answering the most searched question: *What is climate change?* The hosts and experts, including Dr. Rose Mutiso and Dr. Zeke Hausfather, introduce themselves and discuss their roles in climate and energy research.

05:06

🌡️ Defining Climate Change

The second paragraph dives into the definition of climate change. Zeke explains that climate change involves the heating of the Earth’s system due to human activities such as burning fossil fuels and deforestation. Carbon dioxide (CO2), a greenhouse gas, traps heat, leading to a ‘greenhouse effect’. Adam Levy simplifies the concept, explaining how greenhouse gases naturally insulate the Earth but human activities are intensifying this effect, causing global temperatures to rise. The paragraph also addresses the pressing question of why we haven't stopped exacerbating this ‘nice warm blanket’ of greenhouse gases despite understanding its dangers.

10:10

🌍 The Effects of a Hotter World

This paragraph addresses the direct impacts of global warming on already hot regions and how rising temperatures exacerbate extreme weather events like heatwaves, floods, and wildfires. The hosts and experts describe how rising sea levels and thermal expansion are contributing to widespread devastation in countries like Pakistan. In addition, they discuss how hotter, drier conditions lead to more intense wildfires. The hosts express concern about the long-term effects, including the potential uninhabitability of certain regions, and highlight the growing global consequences of climate change.

🌧️ How Warming Causes Floods

In this section, the hosts explain how global warming leads to more frequent and intense flooding. A warmer atmosphere holds more moisture, resulting in heavier rainfall during storms. They reference Pakistan’s devastating floods, which have killed thousands and displaced millions. Additionally, they explain thermal expansion (warmer oceans expanding) and ice sheet melting, which both contribute to rising sea levels. The paragraph transitions to the discussion of droughts, where certain areas become drier, creating ideal conditions for wildfires. They emphasize that the impacts of climate change are interconnected and affect regions worldwide.

🔥 Droughts, Fires, and Climate Change's Global Reach

This paragraph emphasizes the far-reaching and escalating impacts of climate change, from droughts in some areas to deadly heatwaves in places like Western Europe, where many thousands have already lost their lives. It warns that previously cooler regions are not immune, and regions like the Mediterranean and the Middle East are at risk of becoming too hot to live in. Rising sea levels also pose a threat to low-lying island nations, which may face total submersion if climate change continues unchecked. The experts highlight the vulnerability of coastal areas and the urgent need for climate action.

🔋 Energy Systems and Clean Alternatives

This section discusses the challenge of reducing greenhouse gas emissions while maintaining modern life, which heavily depends on fossil fuels for energy, transportation, and industry. Rose emphasizes that while fossil fuels have historically powered the world, they also produce harmful CO2 emissions. However, the conversation shifts toward optimism as the experts highlight exciting developments in renewable energy, including solar and wind power, and the growing adoption of electric vehicles. The hosts emphasize the importance of transforming energy systems to reduce dependence on fossil fuels and make sustainable living more accessible.

🚨 Is It Too Late to Act?

In this paragraph, the experts dismiss the notion that it's too late to address climate change. Zeke uses the analogy of getting punched in the face to explain that regardless of how far the damage has gone, stopping it remains crucial. Every fraction of a degree of warming prevented makes a significant difference. The conversation highlights the importance of continued efforts to limit warming, emphasizing that there is no single tipping point. Instead, the effects of climate change worsen progressively, and every action taken to reduce warming is valuable in mitigating its future impact.

🗳️ What Can We Do to Make a Difference?

This final paragraph focuses on individual actions to combat climate change, particularly through political engagement. The hosts stress the importance of voting for policymakers who prioritize climate action, as they have a profound influence on how governments address the crisis. The experts urge listeners to stay informed, hold politicians accountable, and advocate for clean energy solutions. They conclude on a hopeful note, mentioning how renewable energy has become increasingly affordable and how public awareness of climate change has surged in recent years. This growing momentum gives them hope for the future.

Keywords

💡Climate Change

Climate change refers to the long-term alteration of temperature and typical weather patterns in a place. In the script, it is described as a result of human activities, such as burning fossil fuels and deforestation, which add greenhouse gases to the atmosphere. This leads to global warming, which has wide-ranging impacts on weather, ecosystems, and human life.

💡Greenhouse Gases

Greenhouse gases, like carbon dioxide, trap heat in the Earth's atmosphere, functioning like a 'warm blanket.' While they are naturally present and essential for maintaining a livable climate, the script explains that human activities are increasing their concentration, leading to excessive warming and climate change. Examples include emissions from burning fossil fuels.

💡Fossil Fuels

Fossil fuels are energy sources like coal, oil, and natural gas, formed from the remains of ancient plants and animals. In the video, fossil fuels are highlighted as a major cause of climate change, as burning them releases carbon dioxide, a key greenhouse gas. They are described as historically efficient energy sources but with detrimental environmental impacts.

💡Greenhouse Effect

The greenhouse effect is the process by which greenhouse gases trap heat from the sun in the Earth's atmosphere, warming the planet. In the script, this concept is linked to climate change, as human activities are intensifying the effect, leading to more heat being trapped and causing global temperatures to rise.

💡Renewable Energy

Renewable energy refers to energy derived from sources that are replenished naturally, like solar and wind power. The script emphasizes that renewable energy is key to mitigating climate change, as it offers cleaner alternatives to fossil fuels. Advances in renewable energy technologies, particularly the reduced costs of solar and wind power, provide hope for a sustainable energy future.

💡Global Warming

Global warming is the gradual increase in the Earth's average surface temperature due to human activities that add greenhouse gases to the atmosphere. The script frequently references global warming as the central issue driving climate change, leading to extreme weather events, sea-level rise, and shifts in ecosystems.

💡Sea Level Rise

Sea level rise refers to the increase in the global average sea level, mainly due to the thermal expansion of water and the melting of ice sheets and glaciers caused by global warming. The script mentions how rising sea levels threaten low-lying island nations, which could become uninhabitable due to this phenomenon.

💡Extreme Weather Events

Extreme weather events are abnormal or severe weather conditions, such as heatwaves, floods, droughts, and wildfires. The script explains how climate change intensifies these events, with warmer temperatures leading to more frequent and severe occurrences of natural disasters across the globe.

💡Thermal Expansion

Thermal expansion is the increase in water volume as it warms, causing sea levels to rise. In the script, it is explained as one of the factors driving rising sea levels, alongside the melting of ice sheets. This concept helps illustrate how global warming impacts the world's oceans and coastal regions.

💡Energy Transition

Energy transition refers to the shift from fossil-fuel-based energy systems to renewable, cleaner sources of energy, such as solar and wind power. The script highlights this transition as necessary for reducing greenhouse gas emissions and tackling climate change, with examples like solar panels and electric vehicles representing the shift in energy production and consumption.

Highlights

Introduction to The Climate Question podcast and its focus on climate change.

Description of the podcast's setting atop a reactor, symbolizing the energy and climate discussion.

Introduction of Dr. Rose Mutiso and her work on energy, climate, technology, and policy in developing countries.

Introduction of Dr. Zeke Hausfather and his role in producing global temperature records.

Introduction of Adam Levy as a climate scientist and YouTuber.

Explanation of climate change as the addition of heat to the Earth's system due to human activities.

Discussion on the role of greenhouse gases in the atmosphere and their impact on global warming.

The necessity of energy in modern life and the challenge of transitioning from fossil fuels.

The direct effects of a hotter world on living conditions, especially in already hot regions.

Climate change's role in intensifying extreme weather events like heatwaves, floods, droughts, and wildfires.

Explanation of how a warmer atmosphere can lead to increased flooding due to its capacity to hold more water.

Testimony from someone affected by climate change, detailing the devastating floods in Pakistan.

Discussion on sea level rise due to thermal expansion and melting ice sheets.

The impact of droughts on regions experiencing hotter and drier conditions, increasing wildfire risks.

The potential for certain regions to become uninhabitable due to extreme heat.

The importance of transitioning to cleaner and more efficient energy production methods.

The role of electric vehicles and renewable energy in reducing reliance on fossil fuels.

The importance of continuous action against climate change, emphasizing that it's never too late to make a difference.

Advice on how individuals can make a difference by engaging in politics and supporting climate action.

Optimism about the progress in renewable energy affordability and public awareness of climate change.

Conclusion and invitation to join the podcast for more insights on climate change.

Transcripts

Hello and welcome to The Climate Question – I’m Jordan Dunbar. We’re a

weekly podcast from the BBC World Service.

We speak to experts, activists, businesses and reporters from all over the world about the biggest issues when to comes to climate change.

It’s always interesting.

Really, really, really looks like a James Bond film. I'm slightly nervous. We're standing on top

of the reactor. Atoms are being split, minds are being blown.

And sometimes slightly unexpected!

Ah! Are you OK? It's gone now I'm alright. I just throw it back into the water. That was some kind of sea creature

came for you? Yeah.

In this special episode I'm joined by experts and friends of our show to answer one of the most commonly searched

questions: What is climate change?

OK we’ve got Dr Rose Mutiso - Rose what do you do? I'm the research director at the Energy for Growth Hub. I work on

energy and climate, technology and policy in developing countries.

Dr Zeke Hausfather - what do you do? I'm a research scientist at Berkeley

Earth which helps produce one of the global temperature records.

Adam - complete the trio. Adam Levy. My surname is pronounced Levy, like, leave me alone. So I suppose

a climate scientist and YouTuber.

Thanks guys. A lot of people are too afraid to ask the really simple questions when it comes to big

news stories as they don’t want to look stupid - but not me! Think of me as an

inquisitive five year old – I'm just going to keep asking ‘Why why why?’ on your behalf.

But first a what.... What is climate change? Zeke what does that term actually mean?

So when we talk about climate change, what we're really talking about is heat

being added to the Earth system. So as humans burn fossil fuels, we dig up

from underground, or as we cut down forests that have been standing for

hundreds of thousands of years, we are putting carbon dioxide into

the atmosphere. Carbon dioxide is a greenhouse gas,

and the more greenhouse gas you have in the atmosphere the more of the sun's heat

gets trapped in the atmosphere and the warmer the surface gets and that's why

it's called a greenhouse effect.

Wait a minute! I said simple. Adam, what are these greenhouse gases people keep talking about?

Greenhouse gases on their own are actually great, they exist naturally in the atmosphere. And if they didn't,

the world would be way too cold for comfort. So greenhouse gases on their own good,

they work like a nice, warm blanket, keeping the Earth from the cold space

around us helping insulate the planet. The problem is that we're adding to them hugely.

So it doesn't take a doctorate in climate science to understand that

if something insulates the planet and you add a whole bunch

more of it to the atmosphere, then you're going to have more of that insulation effect

and things are going to start to heat up. And that's exactly what we're seeing.

There’s been so much coverage of climate change and this global warming

you’d think this is something we’d have changed by now. Another basic question.

Why haven’t we just stopped adding to this ‘nice warm blanket?’

All of the systems that underpin our lives, so how we produce food to eat, how we

create energy to heat our homes, how we create electricity to power our devices and our

machines, how we fuel our cars. All of these processes require energy inputs.

I focus on the energy sector, my energy sector is the biggest part of the problems.

How we produce and use energy, really a massive chunk of it. And so

for the most part, historically, we burn fossil fuels to produce energy,

whether it’s heat, whether it's electricity, whether it's fuel, so think of your petrol or your jet fuel.

Fossil fuels are essentially remains from plants and animals from millions of years ago,

under heat and pressure and time create really efficient sources of energy. And so we

burn them. And we can create heat and electricity and everything. But then we

also produce carbon dioxide as a side effect.

OK some people will be thinking I like hot weather, what is so bad about the world heating up?

So the world getting hotter will have some very direct effects on places which are

already pretty hot, you know, if you're in a particularly hot city, and that

suddenly gets a chunk hotter, that's going to make it a lot harder to live in that city.

But beyond that, around the world, we're seeing a whole host of

really scary impacts of climate change already happening today. For example,

climate change is turbocharging all sorts of extreme weather events,

whether that's things like heatwaves, floods, droughts, wildfires.

Someone here was saying it was hotter here than in Africa.

Also the heat comes in the wake of Covid too, so you have Covid, then you have heat, it’s almost biblical.

The effects that Adam mentioned are terrible. Floods, droughts and wildfires. But it’s not

clear to me how the Earth warming would actually create them. It’s ‘why’ time again...

Explain to me how the world getting warmer causes floods. That seems

to be the opposite of what I would have thought would happen.

So a hotter atmosphere works like a more effective sponge, it can hold more water.

And that means when you have really heavy downpour events, there's actually just

more water there in the atmosphere waiting to be rained out. And so when it rains, it pours.

On The Climate Question we have seen first-hand the effects that these impacts can have - we go around the world

to speak with people on the front line of climate change.

Floods have destroyed much of my country, Pakistan. The waters have killed some 1500 people, and displaced millions.

So sea levels rising, there's actually a couple different

factors driven by climate change that cause that. One very simple one that

people don't often appreciate is that as the oceans warm

warm water takes up more space than cold water. And so you get this thing called thermal expansion,

where the warming of the oceans literally causes the water to take up

more space and the sea levels rise because of that. But in addition to that

warmer temperatures cause ice sheets to melt, and not just melt from the top down, but

also to flow faster into the oceans. And we've already seen a huge increase in the

rate of ice loss from Greenland in particular, but also parts of Antarctica

over the last few decades. And so that's been increasingly driving the sea level rise

that we've been seeing globally.

It’s not just the wet stuff we also go from floods to fire.

Some parts of the world are also experiencing more drought as more water gets carried away from those areas.

And so if you have hotter and drier vegetation, if a fire starts it's easier for that fire to find enough

fuel to grow bigger and to spread much more rapidly and much more widely.

Some people will be listening and thinking that all sounds terrible but it hasn’t hit them yet.

Life is busy.

There’s constantly things on the news to be worried about. But climate change will affect all of us...

Europe, for example, a lot of regions around the Mediterranean could potentially become

too hot for people to live in the way that they currently live in these regions.

But heat waves don't just affect regions we currently associate as hot.

Extreme heat is already affecting different parts of the world, the world over today.

And in fact, heat waves in the last couple of years in Western Europe

have claimed many thousands of lives. And these are relatively rich, relatively

cool parts of the world. You then extrapolate that to parts of the world,

which are really hot already, for example, certain Middle Eastern countries,

then you're risking these countries simply becoming too hot for habitation

in coming years. Sea level rise will affect coastal regions, but particularly

vulnerable to sea level rise are countries which we call low-lying island nations,

which are islands which aren't that high above sea level.

And if we can't control climate change, we're looking at these nations effectively

ceasing to exist, the people who live in them needing to relocate their way of

life being extinguished by climate change.

Modern life depends on energy – electricity or fuel. As Rose mentioned, the problem is the system that underpins

nearly all of our life. So do we just stop...you know doing everything?

Obviously, we need to continue to, you know, run our factories and power transportation

systems that can get us from A to B, you know, just because there's climate change

doesn't mean that we stopped needing to eat or to work or to create things that

underpin our modern existence, right. And so the opportunity is that they're kind of

cleaner more efficient, better ways to create energy, right. And so for example,

in electricity sector, so instead of the traditional power plant that, say uses

coal, which is a very kind of, extremely polluting fuel, burns coal to

create electricity, we can make electricity from the sun, using solar panels.

Or we can make electricity with wind turbines right.

But the pace of technological change is really, really exciting. Similarly, for transportation, so

instead of, you know, putting petrol in your cars, now we have electric vehicles

and there's a lot of innovation around that. The way we're designing our cities

to reduce the need for driving, folks are biking, walking, public transit

they're just all of these great approaches that we're taking to try and reduce our reliance on fossil fuels.

Lots of changes are already happening and we’ll each have seen technology improving in our own lives,

so why are some people saying actually it’s too late for solar panels or for electric vehicles. That the world will warm to a point where we can't live in it.

But is that right? Is it too late?

Climate change isn't like that. Climate change, I always say, is more like getting punched in the face.

It doesn't matter how long you've been being punched in the face, you still want that punching to

stop. And so say you set a limit for okay, I only want to be punched 10 times

anything more than that would be a catastrophe. Okay, now you've been punched

11 times. Well, 12 punches are still worse than 11 and 13 is still worse than 12.

And so throwing our hands up and then saying 'Oh, it's too late now'.

That's just not good enough. There's still so much we can do to stop punching ourselves in the face.

We are ultimately in control of our climate destiny, we can decide if we're

going to have 1.5 degrees warming this century, or five degrees warming this century,

or somewhere in between. And one thing that the climate science is pretty clear

on is that every 10th of a degree matters. There's no threshold where

we go from everything being fine to climate change spiralling out of control and

the end of the world. It's not like 1.4 degrees centigrade globally is great and 1.6 degrees

is an apocalyptic hellscape. Rather it gets progressively worse

the more warming we have. And in many ways, the more warming we get, the more worse it gets.

And so if we do end up stuck in a world of 1.8 degrees, or even two degrees, it becomes all

the more important not end up at 2.1 degrees or 2.5 degrees.

There's no point at which it's too late.

For me, after hearing all this, there’s just one question that I have – what can I do to make a difference?

Go and vote. Get engaged in your politics at the

local level of the national level, get involved.

And I know it seems almost like a silly thing to say. But I cannot emphasise how

important is to vote because the people that you vote in - policymakers,

legislators - they have so much sway over how we tackle climate change.

So all of this stuff is really decided at the level of policy and behind policy

are politicians and I know they're not always our favourite people, but that's on us

because we pick them. And so I just say, always get engaged. You know, do

your civic duty, read up on the candidates, make sure that people that are getting

voted into power are people who have, you know, practical solutions, understand the issues.

And that’s actually a question we get asked a lot on the podcast

and you can hear an entire episode on changes you can make to help – find it wherever

you get your podcasts. Adam, please tell me things are changing for the better or there’s at least some hope!

I would say they're two really huge changes since I started working on climate change

around 12 years ago. The first is back then when I started

renewables were still pretty expensive. And so the big question was, well we

know we need to make this shift, how can we? How can we get people to spend more money to make

this electricity? Well, that has been turned absolutely on its head in the

last years, as solar and wind have become just breathtakingly cheap.

On top of that, the big, big change that I've seen is that when I started working on climate

change, people weren't really talking about it. And it often felt like us

climate scientists was screaming into a void.

Well, it's not like that anymore. People are talking about climate change more and more with each other.

People are acting on climate change in their personal lives and pushing for climate

action from governments and companies. And climate change is now ranked world over

as one of people's top concerns. And so the fact that we're all now taking

this more seriously, talking about it more and acting on it more, gives me a

huge amount more hope than I had a few years ago.

So that’s our answer to ‘What is climate change?’

If you’ve enjoyed this episode - good news! We do this every week. We take a question about climate change

and answer it. The Climate Question tackles these issues with a global

perspective, so wherever you live we'll be finding out how climate change is

affecting you and what could be done about it.

Join us as we meet experts, activists, actors, businesses, scientists and everyday people as they deal

with the world’s biggest challenge – climate change.