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

[00:00:00] Jordan Dunbar: Hello and welcome to the climate question. I'm Jordan Dunbar. We're a weekly podcast from the BBC World Service and we speak to experts, activists, businesses and reporters from all over the world about the biggest issues when it 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. Mines are being blown. And sometimes, slightly unexpected. [00:00:32] Speaker 2: Are you okay? It's good now. All right. I just put it back into the water. [00:00:36] Jordan Dunbar: 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? Okay, we've got Dr. Rose Matiso. Rose, [00:00:53] Dr. Rose Matiso: 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 Housefather, what do you do? I'm a research [00:01:07] Dr. Zeke Housefather: scientist at Berkeley Earth, which helps produce one of the global temperature records. Adam, [00:01:10] Adam Levy: complete the trio. Adam Levy. My surname is pronounced Levy, like leave me alone. So I suppose climate scientist and YouTuber. Thanks guys. Okay, a lot of people are too afraid to ask the really simple [00:01:25] Jordan Dunbar: 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? [00:01:44] Dr. Zeke Housefather: 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 that we dig up from underground, or as we cut down forests that have been standing for hundreds or 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. [00:02:09] Jordan Dunbar: And that's why it's called a greenhouse effect. Wait a minute, I said simple. Adam, what are these [00:02:14] Adam Levy: 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. And 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. [00:02:55] Jordan Dunbar: 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, [00:03:07] Dr. Rose Matiso: 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. The energy sector is the biggest part of the problem. How we produce and use energy is 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. [00:04:05] Jordan Dunbar: Okay, some people will be thinking, I like hot weather. What is so bad about the world heating up? [00:04:11] Adam Levy: 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 Africa. [00:04:49] Dr. Zeke Housefather: Yeah, we were hearing that. [00:04:51] Jordan Dunbar: Also, the heat comes in the wake of COVID too. So you've got COVID and then you've got heat. Yeah, 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. [00:05:20] Adam Levy: 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. [00:05:39] Jordan Dunbar: On the climate question, we've seen firsthand the effects that these impacts can have. We go around the world to speak with people on the front line of climate change. [00:05:47] Speaker 2: Floods have destroyed much of my country, Pakistan. The waters have killed some 1,500 people and displaced millions. [00:05:55] Dr. Zeke Housefather: So sea levels rising, there's actually a couple different factors driven by climate change that cause that. You know, 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 than the sea levels to rise because of that. But in addition to that, warmer temperatures cause ice sheets to melt, 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. [00:06:38] Jordan Dunbar: And it's not just the wet stuff. We also go from floods to fires. [00:06:43] Adam Levy: 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. [00:07:03] Jordan Dunbar: 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. [00:07:17] Adam Levy: In 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. If 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. [00:08:30] Jordan Dunbar: 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? [00:08:42] Dr. Rose Matiso: Obviously, we need to continue to, you know, run off factories and power transportation systems that can get us from A to B, you know, just because it's climate change doesn't mean that we stop needing to eat or to work or to create things that depend on 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 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. [00:09:56] Jordan Dunbar: 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 the point where we can't live in it? But is that right? Is it too late? [00:10:12] Adam Levy: 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, OK, I only want to be punched 10 times. Anything more than that would be a catastrophe. OK, 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 in there and 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. [00:10:50] Dr. Zeke Housefather: 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 5 degrees warming this century or somewhere in between. And one thing that the climate science is pretty clear on is that every tenth of a degree matters. There's no threshold where we go from everything being fine to climate change spiraling 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 2 degrees, it becomes all the more important than not to end up at 2.1 degrees or 2.5 degrees. There's no point at which it's too late. [00:11:44] Jordan Dunbar: For me, after hearing all this, there is just one question that I have. What can I do to make a difference? [00:11:51] Dr. Rose Matiso: Go and vote. Get engaged in your politics at the local level, at the national level. Get involved. And I know it seems almost like a silly thing to say, but I cannot emphasize how important it is to vote because the people that you vote in, policymakers, legislators, they have so much sway over how we tackle climate change, right? And 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 favorite 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. [00:12:52] Jordan Dunbar: 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. [00:13:09] Adam Levy: I would say there are 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 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. So, 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 were 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, from 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. [00:14:21] Jordan Dunbar: 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 we 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 can 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.