It's become strangely normal to tell our kids that they're going to die from climate change. If sea-level rise doesn’t get them, then a wildfire will, or a global famine, or crop failures. Maybe a fatal heat wave, the insect apocalypse or the fishless oceans. These are the headlines we've all been told will be the end of humanity.
So we shouldn't be surprised, then, that young people today feel crippled with anxiety. A large international survey asked 10,000 young people about their attitudes to climate change. More than half said they think humanity’s doomed; three-quarters find the future frightening; and more than one in three are hesitant to have children of their own. Young people today truly feel like they could be the last generation. In fact, prominent activist groups actually take on this very name.
Now I get this feeling, I've been there. I used to feel like humanity was doomed, and despite having multiple environmental degrees, I felt completely helpless to do anything about it.
But I'm a data scientist, and after years poring over the data on how far humanity's come and how quickly things are now moving, my perspective on this has changed. I think we've got this framing upside down. Far from being the last generation, I think we will be the first generation: the first generation to be sustainable.
When we think about sustainability, we might imagine humans have only become unsustainable in the very recent past, that our ancestors lived in perfect balance with nature and only recently has that been knocked off. Unfortunately, this is not true. If we're nostalgic for sustainable paths to rewind back to, there is none. The world has never been sustainable.
Now I get that that's a controversial statement, so let me explain why. When we think about the definition of sustainability, we might imagine something like this: "having a low environmental impact to protect future generations." And it's true, by this definition, many of our ancestors were sustainable. They did have a low environmental impact. But the reason they had a low environmental impact is because the populations were tiny. And the reason their populations were tiny is because half of children died before reaching puberty. Half of children died. That, then, raises the question: Is that what we really think sustainability is? Is that the world we want to maintain and preserve, one where half of our children die? Hope your answer to that is no. If we care about human suffering, we need to add another dimension to this. We need to also provide a good life for everyone today.
Now that gives our definition two halves. If we fail on either half, we have failed to be sustainable. That's where our ancestors were never sustainable. They never achieved the first half of the equation. And over the last few centuries, the world has made amazing progress on the first half. As we've shown at Our World in Data, child mortality is now down to four percent. Extreme poverty used to be the default, now less than one in 10 people live there. Literacy and education used to be rare; now, most children in the world get the opportunity to go to school. But the world as it is today is still unacceptable. It's unacceptable that millions of children die every year, that hundreds of millions live on less than two dollars a day, which is an incredibly low poverty line. But pick almost any metric of human wellbeing, and you'll find that the world has become a much better place.
But that progress has come at a cost. It's come at a cost to the environment. We burn wood and fossil fuels for energy. We expanded farmlands at the cost of forests, and our insatiable appetite for meat means we now use half of the world's habitable land for farming. We kill billions of animals every year. These are the trends that make us feel doomed. We see these lines rising, and we assume they might never stop.
But more recent data tells us a slightly different story. A more hopeful story, that we can turn things around. This is per-capita CO2 emissions in the UK since 1750. Over the last few decades, emissions in the UK have halved. That means that my carbon footprint today is less than half that of my grandparents' when they were my age. That's despite the fact I live a much more extravagant lifestyle, or, as they'd put it, "You youngsters just don't know how good you've got it these days."
(Laughter)
Now, you might think the UK's cheating here. It used to be this industrial powerhouse, now it gets China, India and Bangladesh to produce its stuff for it. Maybe it's just offshored all these emissions. There's a bit of truth to this -- when we adjust for trade, emissions in the UK are higher -- but we still see this dramatic decline over the last few decades. Offshoring is a bit of the story, but it's not the entire story. At the same time, the UK has increased its GDP. GDP has gone up, while emissions have come down. And it's not the only country to achieve this. You will see the same for the US, for Germany, France, Spain, Portugal. A long list of countries have increased GDP while reducing their emissions. And again, this is not just because they've offshored them. The notion that economic growth has to be incompatible with reducing our environmental impact is simply wrong.
Now rich countries are reducing their emissions, but low- and middle-income countries are increasing theirs. What does this mean at a global level? Well, total CO2 emissions are now beginning to flatline, but actually, emissions per person already peaked a decade ago. That means the emissions of the average person in the world today have peaked, and are now falling. And we will see a peak in total CO2 emissions soon.
Now, why is this happening? A big driver has been technological change. Here, we see coal production in the UK since 1700. Now the UK was the birthplace of industrial coal, and it has now died there. When I was born, more than half of the UK's electricity was coming from coal. This is now less than two percent. And it’s dying in many other countries too. You will see the same for the US, Germany, Denmark, Spain, Portugal, Greece, Ireland. In many countries in the world, coal is dying. Taking its place are renewables, where costs are plummeting. The cost of solar has fallen by 99.8 percent since 1970, fallen by 90 percent in the last decade alone. And if you're worried that it looks like this price trend is leveling off, don't be. When we zoom in, we see that the price of solar continues to fall. And the same is true for wind. Go back a decade, and solar and wind were among the most expensive energy technologies we had. That is why the world was not making progress, that is why countries were not deploying them -- they were far too expensive. But just ten years on, and that script has flipped. In many countries in the world, solar and wind are now the cheapest.
Now if we're going to have renewables, we're going to need energy storage. But there's good news there too. The price of batteries has fallen by 98 percent since 1990. If you take the battery you'd find in a Tesla today, go back to 1990, it would have cost one million dollars. It now costs just 12,000. That’s completely transformed the world of energy storage and completely transformed the world of transport. Global sales of petrol and diesel cars have already peaked -- they peaked in 2017, and they are now falling. Taking their place are electric cars, where, in a space of just a few years, sales are going through the roof.
And from energy and transport to the food we eat, you might imagine that global deforestation is at its highest level ever. But actually, global deforestation peaked decades ago and is now falling. But actually, it's better than that, because many countries are now regrowing their old forests, such that the net decline is even more impressive.
Now, why is this happening? A big driver has been increases in crop yields. For all of our agricultural history, crop yields were low and stagnant. Farmers had basically no opportunities to increase them. Over the last century, across many countries and many different crop types, crop yields have skyrocketed. Here, we see it for the US, for corn, where yields have grown sixfold, from two tonnes to 12 tonnes. Now what this means is we can grow a lot more food from a lot less land. The amount of land used to produce corn in the US has not increased in over a century, but look at the change in corn production.
My main point here is that in the past, human progress had to come at the cost of the environment. If we wanted energy, we had to burn wood or we had to burn fossil fuels. If we wanted to grow more food, we had to expand farmland, often at the cost of forests. But technology and innovation means we're very quickly decoupling these impacts, such that this conflict is no longer true.
Let's then think about the world that we can have. We need to achieve the first half of our equation. We need to end global poverty. And here, I'm not talking about raising everyone above a two-dollar-a-day poverty line. That is simply not good enough. We need to provide everyone with a good, comfortable life. No child should die from a cause that’s preventable. Every child should get the opportunity to go to school and get an education. At the same time, we need to peak and reduce our CO2 emissions; we need to move away from fossil fuels; and we need to end deforestation, while feeding eight, nine, ten billion people, at the same time.
How do we do that? How do we become the First Generation? First, our low-carbon technologies need to become the default. There's two ways to do this. The first is to make sure that they are affordable, to make sure that they are the cheapest option. Solar and wind are already cheaper than coal, electric cars will soon be cheaper than gasoline, and alternative proteins need to be cheaper than meat. The other way to do this is to make sure these technologies are better. Environmental products have often been promoted as this happy gimmick, but they need to go mainstream, and for that, they need to be better than the high-carbon alternatives.
Now my brother recently got an electric car. He didn't get an electric car because he really cares about the environment. He does not want to be the next Greta Thunberg. And he definitely does not want to be like me.
(Laughter)
He got an electric car because the design and the driving experience were far better than the petrol alternatives. That is how we make low-carbon technologies the default. We need to reframe the way we talk about sustainability as often promoted as a sacrifice. Environmental messaging is often built on scarcity. It’s about reducing our lives back to the bare minimum and no more. But this is not a vision that inspires anyone. This is not the future we want to build. We need to reframe sustainability as an opportunity, because it is an opportunity. It's an opportunity to provide clean, abundant energy for everyone, whether that's powering cities or countries, or getting rural communities connected for the very first time. It’s about not being at the whims of fossil-fuel markets or having millions plunged into fuel poverty when dictators invade neighboring countries. It's about breathing clean air. Here, we see the decline in harmful air pollution in the US, from 2005 to 2021. Stopping people from dying is not a sacrifice.
Finally, it's a way to rethink the way we live our lives, the way we design our cities and our communities. Here, we see Copenhagen, with bikes on the road, or Amsterdam, where you have layer upon layer of bike rack. Now I'm not saying this is how our cities have to look. We can design them in any way we want. What I'm saying is that sustainability gives us the shelf to rethink the way we do things.
Finally, we need to rethink the way we use data. As a data scientist, I take this very seriously. The environmentalists have done an amazing job of waking the world up to these problems. Those charts of rising CO2 and rising temperature have been absolutely critical. They're why I'm on the stage today, they're why I got involved in this in the first place. But there's a limit. When that's all we see, we become paralyzed. We see these lines rising, and we assume that they might never stop. We assume that no progress has been made, that nothing good is happening. But as we've just seen, this couldn't be further from the truth. We need to use data to inspire, to show what the problems are, also what the solutions are, and we need to show real signs of progress from countries, individuals, companies.
Historically, our sustainability equation went like this. It was one or the other. You could not have both at the same time. We can be the first generation that does achieve both. Now the emphasis here is on "can." None of this is inevitable. It's not even inevitable that we'd have this opportunity in the first place. We're only here because of the relentless work of environmentalists, activists, scientists, engineers, entrepreneurs, communicators, determined to make the world a better place. They have brought us here, and we need to take that forward. We need to do it bigger, and we need to do it much, much faster.
But we do have the opportunity to be the first generation that builds a sustainable world. Let's take it.
Thank you.
(Cheers and applause)
