The idea that a rapidly growing population would inevitably result in economic and resource crisis has been part of the popular imagination since Rev. Thomas Malthus published his essay Principle of Population in 1798. Malthus has been largely disproven but the idea that population is the greatest threat remained influential and was seen repeated in the work of writers like Paul Ehrlich.
The Malthusian theory allowed aspects of public discourse to shift the focus from any major behavioural changes for the developed world, shifting blame away from high income regions responsible for much of the environmental damage, to the actions of less developed countries, the ever-present “them”.
The human population of earth reached 7.3 billion in 2016. Population rate of growth peaked in the 1960s at just over 2% annually but despite the fact that fertility rates have fallen in 48% of the world to less than 2.1 (2.6 is needed to replace population) the upward trend in population growth is not expected to peak for another 40 years. It is this fact that is causing concern among environmentalists given the perceived rate of climate change and the challenge this presents for sustainable development.
Economic development usually includes a predicable set of social changes, standards of health and education rise, consumption increases and the social position of women changes leading to a reduction in birth rates. This is a paradox for sustainable development as while population falls with economic growth consumption per capita increases. Consumption and carbon emissions are considerably higher among wealthier countries who score highly on the Human Development Index, but this relationship is not consistent.
Consumption as a percentage of GDP in the UK is twice that of Singapore but both countries score almost the same on the HDI. This means that social and cultural norms can have a significant influence on consumption habits and simple population figures are not an accurate indication of the capacity of a society to achieve sustainable development.
Consumption and environmental degradation have to be placed in the context of global inequality. Race and class are major influences on the likelihood of communities to experience the ill-effects of pollution and industrial activities. Poor people are often highly dependent on their environment for livelihoods and suffer most acutely the effects of pollution and climate change. Resources for reacting to increased environmental instability, even inside developed states, are influenced by social divisions, such as race and class, as was seen in the aftermath of Hurricane Katrina.
Another aspect of this are the debates between the Global North and South about which nations should potentially bear the brunt of curbing their economic development in order to cut carbon emissions. Per capita carbon dioxide emissions are 10-50 times higher in high income countries than in low income countries and energy insufficiency is a major component of poverty in low income countries. As a result, there is political resistance in many developing countries to signing up to international environmental treaties for fear of stunting their economic growth. Tying environmental regulations to debt relief or releasing holds on agricultural patents can make it easier for developing countries to participate in international environmental protection without risking their economic security. This could also assist developing countries to develop without causing the same ecological damage as the current highest income states.
The disproportionate effect of climate change on poorer and more agrarian communities is effecting food security. The desertification of previous pastoral land disproportionally effects poor regions. Food insecurity is linked to both a low level of economic development and to rapid population growth. There is an argument that it is already possible to feed the current population on the food produced but that resources are poorly distributed.
Even by 1976, the USA had experienced a serious shift to intensive farming, with the number of separate farms changing from 6.8 million in the 1930s to 2.8 million by the 1970s and 1% of cattle feed lots raising 60% of beef cattle. Competition between land uses (between food and biofuel say) and this intensive farming is having a negative impact through rising carbon emission, reduced biodiversity, deforestation and degraded soil. This environmental impact in turn reduces the available arable land for food production. The globalised food economy relies on a great deal of import/export. This meant that when oil prices doubled in 2008 food prices rose by about 66% sparking civil unrest in a number of poorer nations.
The unregulated nature of many the companies involved in this food export results in a focus on short term interests to maximise profits causing environmental harm and food insecurity. There are a number of modern situations reminescient of the Irish famine where food continued to be grown for export but this food was not available to Irish farmers who worked the land but did not own it. The monopolisation of land and natural resources is contributing to food insecurity through break-down of the distributive function of human economic systems.
It is also possible that negative population growth could hinder sustainable development. A negative growth rate results in aging populations which can slow economic growth. There are measure it is possible to build into a society to mitigated the negative economic effects of an aging population, such as employment policies for older people and a stable health system, these systems are not in place in most of the world. Therefore, to simply slow or halt population would not assure wellbeing without addressing the underlying infrastructure, income inequalities and global consumption rates currently at play .
Population growth can exacerbate environmental degradation through pollution, carbon emissions and resource consumption. This environmental damage in turn hinders sustainable development in many of the world’s least developed regions, especially food and water security. But focusing on population growth and fertility rates distracts from the need to reform resource distribution to give weight to the potential hidden costs of environmental and social damage outside of short-term profit; then the subsequent economic and social development could lead to a natural slowing of population growth which could in turn lead to a more sustainable future.
George, Susan (1976) How the Other Half Dies Penguin: England
Jacskson, Tim (2009) Prosperity without Growth: Economics for a Finite Planet Earthscan
Mohai, Paul; Pellow, David and Roberts, J. Timmons ‘Environmental Justice’ Annual Review of Environment and Resources 34 p. 405-430
Remoff, Heather (2016) ‘Malthus, Darwin, and the Descent of Economics’ The American Journal of Economics and Sociology 75:4 p. 862–903
UN (2011) World population prospects: the 2010 revision Department of Economic and Social Affairs United Nations: New York
UNDP (2011) Human development report 2011. Sustainability and equity: a better future for all United Nations Development Programme: New York, NY
Urdal, Henrik (2005) ‘People vs. Malthus: Population Pressure, Environmental Degradation, and Armed Conflict Revisited’ Journal of Peace Research42:4 p. 417-34