We need an economy that doesn't choke the Earth
James Renwick is a climate scientist at Victoria University of Wellington, and worked as an author for the Intergovernmental Panel on Climate Change. He has published a book, Under The Weather. OPINION: We live on a finite planet. One with a fixed number of square metres of land, and with a fixed number of tons of copper and lithium and oil and all other resources. We have only so much room to move and only so much stuff to feed into our economic activity. On a finite planet, never-ending growth of anything is unsustainable. Eventually, we will run out of space, of food, of goods to house and clothe and feed everyone. And of biodiversity that sustains us all. To take the most basic example, think about human population. Currently, there are about 8 billion people on the planet. And there are around 150 trillion square metres of land available (thats all the land surface, including mountains and deserts, the lot I am being generous here). So right now we each have around 18 thousand square metres each, around two and a half rugby fields, if the worlds land was divided up equally. That sounds enough to grow some food to live on, and even to provide the resources needed for housing, for energy production, for communications, and for all the add-ons in what weve come to know as civilisation. All good, today, for those of us who have access to at least that much land and resources. Lets imagine that global population growth is 1% per year, roughly what it has averaged in recent years. Then, by the end of this century we would be down around to one rugby pitch each, in terms of available land. Seventy years later, half a rugby pitch each, and so on. I am not sure how much land each person really needs to live on, but pretty soon (after a few generations) things would be getting tight. Left alone at 1% increase per year, there would be as many people as square metres of ground on earth within 1000 years roughly 30 to 40 human generations. Our population, and the existence of most species, would crash long before that point. Already, humanity and its farm animals make up over 95 percent of the mammal biomass on land. As our numbers increase, and those of our domestic animals, we will squeeze out more and more of whats left of natural habitats. Thats why its good news population growth appears to be slowing. The UN predicts that global population could plateau below 11 billion by the end of this century possibly a sustainable number. Even so, a stable population isnt sustainable if its using up an unsustainable fraction of the earths resources each year. Because most countries rely on the model of never-ending economic growth, we use more of these resources every year. The idea of overshoot has been used for 50 years to tell us where we are with resource use. Currently, its estimated that the global community uses up a years worth of sustainable resources by late July , while it was in December back in the early 1970s. That date is much earlier for developed countries like New Zealand, where the overshoot date is now in mid-April . Many of the least-developed countries dont have an overshoot date, as they use a sustainable fraction of the earths resources every year. So, as a global society, to become sustainable, we have to cut down rapidly on our resource use. And ideally, we remove some of the international inequities in the process. Not only that, we need to stop growing our economies. Economic growth eats up more and more of the worlds resources every year, even if populations are stable. There is no law of nature that says we have to have growth in GDP every year, it is just what we have got used to. But we have to move away from that model to have any chance of stabilising resource use, greenhouse gas emissions, biodiversity, and our effect on the planet. To have any chance of our civilisation, of our nation-states, surviving. The degrowth movement describes how we might achieve this. It involves moving towards a sharing economy that doesnt need to grow. Resources are distributed more evenly, with widespread government support, cooperatives and local commerce thrive, goods are reused and recycled as much as possible. Working hours are reduced so we work less and enjoy the rest of our lives more. A little like the experience many of us had in the Covid lockdowns in 2020. That all sounds great to me, but it is a model of social and economic activity that is the opposite of the direction developed countries have moved in recent decades. It would be strongly opposed by many I expect, as we have become very used to the way our current economy and lifestyles run. We seem to depend on all that production, all those goods coming in from around the world, all that resource use, all that shopping. But, it doesnt have to be that way. As the author Ursula K. LeGuin once said, We live in capitalism. Its power seems inescapable; so did the divine right of kings. Humanity has the power to change the way it lives, it has certainly happened in the past. We can change the model if we want to. And if we dont get away from economic growth, we will eat up all the earths resources at some point, just like wed eat up all the earths land if we let population keep growing. It is not just an interesting idea, it is an imperative if our current civilisation is going to endure for centuries into the future. Based on current trends, well be lucky to endure to the end of this century. So, stop population growth. Stop economic growth. Find ways to use a truly sustainable fraction of the earths resources every year. Easy I dont think so. Can we do it? I hope so, because I believe in us, in the value of humanity. I want my children and their children, and their children, to have a good future to look forward to.