Population Matters

The following is a reflection on this overshoot index produced by Population Matters.

I have a considerable interest in environmental sustainability issues. I believe it is abundantly clear that people on earth in general are not taking remotely seriously enough the medium- and long-term impacts of many of the habits of modern lifestyle on the planet's overall ecological systems and natural environment. We consume far too much, and we consider much of this a kind of basic right - whether it be blithely devouring meat as a daily staple or feeling entitled to fly away for a foreign holiday. We also throw away too much, and the two are of course closely connected. The modern ubiquitous use of plastics which took off around the middle of the last century seems to me a particular case where a sense of romantic nostalgia for an earlier time is hard to criticise. With paper bags and, even, mahogany furniture, one could have at least in theory regulated fairly straightforwardly for sustainable management of the resource of woodland. Of course we have to look back rather further for an age before industrial pollution; further and further for before the eradication of wolves, bears, lynx (or *loxes as we might call them had we retained any folk-memory of them; I rather feel the word "lox", for "lynx" (which is Greek), should be revived if they are ever successfully reintroduced), aurochs, or whatever other animal we have long since forgotten that people once managed to live alongside in this country.*

On the particular idea of population overshoot however, I wish only to say that I sense a certain problem with this sort of measure because it seems to essentially ignore trade: this is deliberate, but I think it is nevertheless a failing. Ecological overshoot at the national level is essentially (population density / renewable resources) x (levels of consumption): but because of global trade systems, for wealthy temperate-climate countries, I think it can perhaps be misleading to attach too much importance to such figures. They present at best an unattainable ideal, where population size is carefully calculated for each country to match its capacity: it is of course far too late for that, modern countries' natural growth rates and net migration are not controlled by this understanding and probably never will be. Presumably, there will or at least can always be trade, including in renewable resources; but in sophisticated modern economies, sustainable or indeed non-renewable natural resources do not limit the value of what a country can export. Therefore, ecological overshoot at the level of individual countries is of relatively little significance: what really matters is the ecological overshoot of the human population of the planet (and I rather think this would probably not be measured in precisely this way).

Nevertheless, ecological overshoot at the national level does have some importance, because countries who are dependent on others for natural resources (renewable or not) surely must assume some responsibility for their responsible management - for example, ensuring their supply chains live up to acceptable environmental standards. (This principle applies to non-environmental ethical consumption considerations as well of course.) The overshoot index could therefore serve as a valuable blueprint for the magnitude of an individual country's duty to defend the environment and promote ecological causes abroad, as well as at home.

As a British person, and one with a perspective which begins quite consciously at the national level of Britain, I am thinking of the example of the United Kingdom; we may be in ecological overshoot, but our population increased by only about ten million between 1950-2000. (It has so far increased by about five million since.) This is of course a very substantial number, but it surely does not come close to explaining the catastrophic collapse in biodiversity during that period - and it certainly nowhere near accounts for the great increases in consumption and pollution during that period. Clearly in such cases we must point to changes in human activity (e.g. land use, use of energy, use of water) rather than human numbers.

On the other hand, the populations of many countries have increased by a vastly greater proportion over this period; others are predicted to see such increases in this half-century. The population of Britain increased by 20%, from about fifty to about sixty million, over the period 1950-2000. Over the same period, the world population increased by 120%, from about two and a half to over six billion. Since around 1950 we have continued to hit the next billion at a rather alarming rate (of course this becomes ever easier as you have more billions to start with, even if birth rates decline): on average, every fourteen and a bit years.

It is this historical perspective that provides the real drama. The rate of population growth has indeed slowed; yet it has continued to increase at a high rate for long enough to have by now (in 2015, at 7.3 billion) almost tripled the world population since 1950. 

Our resource consumption and corresponding waste production, too often confused with standard of living, has advanced far too far and must be scaled back; there is no excuse for inaction at home in one's own life and spheres of influence to do what one can to reduce one's destructive impact on the environment. However, there is also a very great danger now that the global population increase of the last half century or so, taking place largely in what are now developing countries, looking at rich countries as the globally promoted ideal lifestyle, will, in seeking that, help create an environmental crisis far worse even than that which we currently anticipate. The world population must be stabilised.


*This comment is not an argument for reintroduction. On principle I like the idea of reintroduction; in particular for wolves, as I am very fond of them. But for animals which could pose a reasonable risk to humans, however slight, reintroduction does not seem sensible (in my opinion, at the moment).