Population and sustainability

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Our government has recently started handing out money to new mothers to encourage a baby boom, then crowing over the increase in birth rates. This was largely at the request of the business community, but did they stop to ask themselves whether it was even a good idea? Why is it that 'business leaders' want Australia's population to go up and insist that it would be good for the economy, while most scientists think we should try to halt population growth? Do the business leaders have it wrong, or is this a case of competing goals? I think it is the latter.

Most of what I like about Australia, and most of the problems I see overseas, are directly related to population density. The earth can only supply so much food, water, shelter etc. The more people there are, the less there is to go round. Our society is well past the population required for 'economies of scale' and is entering a situation where scarcity of resources is a driving factor. I suspect that most politicians and citizens, on hearing calls from the business community for more babies, assume it has something to do with economies of scale. It doesn't. As the population goes up, the gap between rich and poor tends to expand. Rent, food, clothes and water all become scarcer and more expensive. For the growing 'lower class' these basics take up most or all of the income earned. They become 'wage slaves' who are nominally free, but are enslaved by economic conditions. They become dependent on an efficient, complicated economy to supply scarce resources to those in need on a 'just in time' basis. Meanwhile, those people with enough wits are hard work to get ahead end up in control of a big economy geared toward supplying natural resources that used to be almost free because they were so abundant.

For a 'new' industrialised economy (think 1800-1900), what was good for the business community was often good for the society as a whole. However, as a society enters a scarcity driven economy, the goals of the business community and society as a whole tend to diverge. This is the key point that needs to sink in among the public and politicians.

You have probably thought of one or two main criticisms of this argument, which I will now address:

1) Australia is very wealthy so we are not approaching a scarcity driven economy

2) Technology will always save us

Australia is very wealthy, but it is more due good luck than good management. Rather than protecting us from unsustainable lifestyles, this wealth is more likely to blind us to issues of sustainability by allowing us to live for some time off various forms of capital that we have inherited. Technology will help us in the struggle for sustainability, but should not be viewed as having an infinite capacity to support us. Many of the trends from the past that people associate with generation of wealth are a result of wealth and should not be viewed as a fundamental cause of wealth.

Population vs quality of life

Part of the reason for our vast wealth is our relatively low population. The profits from selling our vast reserves of minerals, produce, tourist destinations etc are being shared between only a few people. The business community claims that we need more people to mine these resources, however that will just mean more people to share the cake between. Mining companies are paying a small fortune to get people to work in harsh conditions in the middle of nowhere. They don't want more people so that we can mine more and have more people earning a fortune in the outback. They want more people so they can pay them less.

Historical sources of wealth

A lot of our vast wealth has historical origins. We have built up a lot of social, engineering and financial capital over the generations. If our population gets too high, we will start eating into this capital. It will not be immediately obvious that this is happening. We won't realise until all this capital is vanishing quickly and is going to run out soon. Of course it won't actually run out. People will just have to work a whole lot harder in order to pay the rent and clothe their children. There won't be any time left to go fishing, or any fish to catch.

Exporting our negative impacts

We are currently exporting a lot of the impacts of our quality of life. We can buy resources we need from overseas. However, as the global population increases, and poor countries like china get their population problem sorted and experience an economic boom, those resources will be harder to come by and we will be forced to sustain our way of life from the land we live on. Obviously, this still allows for trade in some goods which, for a variety of reasons, Australia will always have a surplus of.

Mining renewable resources

Finally, we are eating away at a lot of nominally 'renewable' resources at a rate faster than they are being replenished. Groundwater and topsoil are examples that come to mind. Fish stocks are another good example. The productivity of the world's oceans has been dropping for quite some time, due to the collapse of overharvested stocks and the end of the one-off bounty of virgin stocks in the new world. These are global problems and they vary from place to place, but they impact on all of us as the price of food goes up.]


So far I have touched on the fundamental tradeoff between population and quality of life in a scarcity driven economy. The next factor to throw in is technology. To do this I need to get a bit mathematical, but I only need one equation:

IPAT: Impact=Population x Affluence / Technology

That is, impact (on the environment) is proportional to population, multiplied by affluence (quality of life), divided by technology.

This equation captures the fundamental tradeoff between population and quality of life, along with the role that technology plays. For a given population, more technology allows a higher quality of life for the same environmental impact. Of for a given quality of life, you can squeeze in more people. Many people assume that technology causes environmental problems, but it doesn't. It's just that we often breed faster and get richer at a pace that exceeds the rate at which technology is improving. This population increase is usually a direct result of the technology that enables it, which blurs cause and effect. However, there is no way that the earth could peacefully support the current population and standard of living on the technology from a century ago without destroying our environment.

For the western world technology has kept ahead lately, to the extent that many people have lost touch with the fundamental tradeoffs. In the past, and in poorer countries, a farmer has to split his land between his children and knows that if he has a lot of children, he won't be able to provide for them. Importantly, there is no fundamental reason for technology to continue to keep one step ahead. Jared Diamond has a nice way of explaining the role of technology - as an analogy of a two horse race. One horse represents population, which is increasing and putting us at risk. The other represents technology, which is saving us from self inflicted demise. No-one knows which horse is going to win, only that they keep getting faster and the stakes higher. Is this a gamble we want to make?

More historical sources of wealth

A lot of our affluence is not down to our technology outpacing population increase, it is down to a once-only historical 'blip' that saw a lot of land fall into our hands with little military effort (ie, Australia and America), combined with our ability to buy resources and labour from (comparatively) poor third world countries.


What role does globalisation play in this? It used to be that individual villages, cities or empires had to live sustainably. Over history, Cities and empires have risen due to some key advancement, then collapsed as the population exceeded what is sustainable and the society started cannibalising itself. The larger the society, the more spectacular the collapse. Bigger societies can afford more complicated systems to sustain themselves. But these systems rely on things like trust (a form of social capital). When these systems break down, the people have to get by on old systems that cannot support the population. They have to invest more in self defence, because the neighbours are getting hungry and eyeing off the food supply. What globalisation means is that we are one massive interconnected global society that cannot pillage from distant lands. We can no longer shield ourselves from the impact of the collapse of a small nation. The people of that nation simply become more dependent on neighbouring countries, at the same time as straining their military resources and their social capital. Think of what hordes of refugees does to the cohesiveness of our society, then image we weren't so lucky to be surrounding by shark infested waters. (OK the sharks have all been finned by illegal fishermen, but you get the picture).

How does this all relate to sustainability?

Going back to the IPAT equation (I=PA/T), sustainability is driven by impact on the environment. If it is greater than what the environment can support, then our society will eventually collapse. There can be long time delays in this, because there are various forms of capital that we can slowly eat away at. For example, we can get by for a long time by 'mining' environmental capital - depleting topsoil to grow lots of food, draining underground aquifers to irrigate and relying on polluting technology and pesticides that insects are adapting to. But that can't go on forever. Rather than causing and immediate disaster, living unsustainably means that we are slowly eating away at that capital. The complexity of our society and the long time delay (sometimes several generations) means that sustainability is difficult to define and even more difficult to measure. Even for obvious things like fish stocks, if each generation starts with an already depleted ocean they may not even notice the small loss with each generation, let alone the big loss that has occurred since their great grandparents first went fishing.

What do we risk losing?

So what are those luxuries that we risk losing due to our government's misguided baby bonus? It is not ipods or cars, as we can always make enough of those to keep us distracted. What we risk is losing the simple pleasures and having to make do with the expensive ones. Simple pleasures like

  • having a long shower and letting the kids play under the sprinkler in the back yard,
  • having a decent backyard without having to commute for an hour to get to work
  • owning that backyard, and the home on it (OK, maybe that's not a 'simple' pleasure)
  • eating beef, which takes up a lot of land and water and emits a lot of greenhouse gasses
  • being able to afford to eat fresh, good quality fruits and vegetables - maybe even ones grown in that large backyard with all that free time you get on the weekend
  • the ability to go fishing and catch a decent feed
  • the untouched wilderness that at the moment is only one hour from the CBD (or is it two? no, it's three now)
Basically, we risk losing the simple life. We risk losing our social diversity and living in strip malls and towns that look like a million other towns in the US. At the moment a lot of these simple pleasures are taken for granted, but gradually they are all going up in price and slipping out of the reach of many of our citizens, to be replaced with TV, the internet and frozen dinners. Many slightly wealthier countries that we look to as an example have already lost this intangible wealth, often without even noticing. So when you hear 'business leaders' calling for more Australians, think twice. It will increase our GDP, but only because they are now selling you what you could previously get for free.


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