Aren’t overconsumption in developed countries and climate change the problems, rather than numbers of people? Industrialised countries are responsible for 80 per cent of the global carbon dioxide build up in the atmosphere while having only 20 per cent of the world’s population.
It is not a question of either reducing carbon emissions or stabilising and reducing populations. Both are necessary if we are to work towards a sustainable future.
It is vital for less developed countries to stabilise their numbers. Otherwise it will be impossible for them to improve their quality of life within the resources available. China and India, for example, the world’s most populous nations, are increasing their consumption as they become more affluent and their per capita emissions will in time become similar to those of economically developed countries.
Isn’t the real problem the fact that consumption is grossly unequal, even within countries, while commercial and governmental decisions are driven by short term competitive pressures rather than long term societal interests?
We would support reductions in inequality and excessive personal consumption, as well as measures to encourage more efficient and environmentally sensitive commercial and governmental practices. However, we believe that human numbers are a major and long term driver of consumption and hence human impact and that therefore a reduction in human numbers can make a contribution to a sustainable future.
Won’t any slowdown in population growth or even reduction in human numbers be too slow to affect the impact of humanity on the environment and limited resources?
It is true that there are real concerns about the short-term outlook for biodiversity loss, climate change and resource availability. Additionally, while birth rates can change relatively quickly, population momentum and increasing longevity delays any effect. Nevertheless, humanity will survive and a substantial reduction in our numbers from projected levels will have a significant and sustained impact on human impact. Moreover, a reduction in human numbers should be seen, not as a stand alone solution, but as a contribution alongside other initiatives promoting sustainability.
Given that larger families are mainly limited to poorer communities, won’t any reduction in family size have little effect on human impact?
Even poorer communities affect the environment through over-exploitation of limited local environments. However, the real impact of growing numbers in poorer communities comes when their situation changes, either through migration to wealthier nations or through development. Moreover, larger families are not uncommon in wealthier communities and we should encourage smaller families in those communities, too.
Global food production has consistently outpaced population growth so isn’t hunger just an issue of fairer distribution rather than too many mouths to feed?
According to the UN, over one billion people throughout the world already suffer from hunger. Increases in agricultural productivity cannot continue indefinitely. Global agriculture now relies heavily on declining non-renewable resources, in particular fuel and artificial fertilisers. Many countries, wealthy ones included, are already consuming more food than they can sustainably produce themselves. This is a problem both of distribution and of total food production. In addition, biofuel crop production is increasingly competing for the land needed to grow food.
There is also the impact of climate change, driven by population growth and industrialisation. Warming oceans and the accelerating melt of the polar ice caps is likely to cause a rise in sea levels threatening many of the world’s major cities and fertile crop-growing deltas. Freshwater glaciers that feed major rivers are shrinking. Climate change is also predicted to adversely affect agricultural productivity in many areas inhabited by rapidly growing populations, eg sub-Saharan Africa.
Won’t better technology help us accommodate the forecast population increase?
More efficient technology should of course be encouraged. It can enable reasonable living standards to be obtained with smaller per capita consumption of resources, but more efficient technology can also lead to increasing extraction rates — chainsaw logging of forests and industrial scale deep sea fishing, for example.
IPAT – A good view of the relationship between technology and environmental impact is given by the IPAT equation of Paul Ehrlich, where I = PAT, i.e. environmental Impact is the product of Population, Affluence (consumption of goods and services) and Technology. There is very little chance of better technology alone solving the I=PAT problem in the foreseeable future. Even if we also reduce our affluence drastically, a sustainable future will be much easier to achieve with fewer people and looks increasingly implausible with more.
Next: Optimum population size