Population: A Problem for Sustainability?
It is estimated that on 31 October 2011 the human population reached 7 billion individuals. It was only 1999 when there were 6 billion people, and it is estimated to reach 8 billion around the year 2025. One billion people added in only 14 years, when it took all of human history until 1804 to reach the first billion. Fortunately the growth rate is slowing. However, despite this seemingly good news, the population is estimated to DOUBLE approximately every 70 years.
Perhaps, then, it is unsurprising that people express grave concern about population generally, and more specifically when we talk about sustainability. Some observations.
Couple together a) the current levels of population growth, doubling as they are every 70 years, and b) near universal mortality reductions, and c) higher birth rates in many developing countries, we are presented with a population growth curve that currently appears to be growing exponentially. University of Illinois’ Dr. Jonathan Tomkin summarises: “Pretty much by definition, an exponential growth curve is not sustainable.
One would find it difficult to disagree that the finite carrying capacity of the earth, in terms of some fairly important things like ecosystem services, land area available for food vs. people, etc. is a distinctly limiting factor on population. “No system is infinitely sustainable”, says Tomkin, but the trouble is, population keeps growing yet we don’t seem to have had the kind of catastrophic crash that Thomas Malthus predicted over two centuries ago.
“The industrial revolution has meant that the average person in the [west] has about 15 times as much wealth today as they did 200 years ago when Malthus wrote his predictions. So rising populations has not led to mass starvation.” Not only that, Tomkin says, “rising population has not made people poorer. In fact, in both of these cases the reverse has happened. … Globally there’s more wealth, there’s less illiteracy, there’s better health.”
But what this fails to recognise is that future trends don’t necessarily follow past trends. The issue is vastly more complex, than a rendering of historical and current data presents. Many of the countries where population is growing fastest are the same countries where there is less wealth, literacy, healthcare and fertility education.
Furthermore, closely related and equally urgent and problematic issues include: food availability, possibility for increased food production, limits of technological innovation, food production and population growth expanding at different ratios.
Availability and use of two principal, finite resources of Water and Energy (fossil fuels), are limiting factors to sustainable population growth.
Social instability, poverty, hunger, economic activity results from overpopulation and the related food and water issues.
Environmental/ecosystem degradation and pollution is also caused by the interconnected issues of population, agriculture, water, energy, however this does not preclude us from shifting away from business as usual towards a restorative system based prosperity as compared to endless growth.
As Tomkin says, “…no matter how you look at sustainability, population is very important because population is showing a growth curve … that is compatible with a J-curve hypothesis, and as we know, and if we have a J-curve hypothesis, and it turns out to be true, we’re headed for a big crash; we’re unsustainable.”
