The premise of this blog is that lifestyles in affluent countries are unsustainable. If we want to end poverty in the developing world without destroying the environment, we need to reduce our consumption. But by how much? What’s the target?
It’s fairly easy to set a benchmark for sustainability. A sustainable lifestyle would be within the planet’s limits, and to be a just lifestyle too it would need to be one that everybody could have. To work that out, you need to know how much of the planet is available to each of us.
All of life’s processes require land. We need land to grow the plants and raise the animals that we eat, to source the timber and cotton and other resources that we use, and to absorb the carbon we emit. That land requirement for each of us is our ‘ecological footprint’. (The image below is from the . It’s not accurate in the proportions, but does illustrate the various components quite nicely)
Not all of the earth’s land is available to us to produce the things we need. Once you have subtracted deserts and mountains and so on, you get a total of 12 billion hectares of productive land. That’s the total planetary space we have to play in. Now we divide that between the world’s population of 7 billion, and we get an earth share of 1.7 global hectares (gha) each.
“If everyone on earth adopted an equitable 1.7 gha lifestyle, the entire human family would be living within the means of nature” say William Rees and Jennie Moore in , which I’m reading at the moment.
The good news is that over half the world already lives at or below that benchmark figure – most of Africa, Asia and Latin America. The bad news is that many others are a long way above it – European average footprints are around 5 or 6 hectares, American and Australian footprints higher still at 8 or 9. “To live fairly within the earth’s means” say Rees and Moore, “Europeans should be implementing policies that will reduce their per-capita ecological footprints by two thirds. Average Americans and Australians should be planning an 80% reduction.”
That’s the challenge, and it’s considerable.
There are a couple of things to note here. First, the simple calculation above assumes that all the world’s productive land should be used by humanity, and we might want to leave some for the other species that share our planet. And that 1.7 gha allowance depends on population, which is increasing. As population rises, the amount of productive land is spread more thin. If we reach 10 billion, we’ll only have 1.2 gha each to work with.
It’s also worth mentioning, since people are looking for things to object to, that an equitable 1.7 gha share is a benchmark figure. There can and will be degrees of inequality around it, and nobody is suggesting any kind of legally binding one planet share or global communism to manage it. But it is what we need to aim for. If we want to continue to live a 7 hectare lifestyle in a world where 1.7 is the fair share, (since I’m writing on the train), we’re like a guy on a packed commuter train who wants a seat for his bag.