An essay on the ecological and socio-economic effects of the current and future global human population size

Abstract

Since the dawn of civilization the world population has grown very slowly, but since the Industrial Revolution in 1750 and especially the Green Revolution around 1950 the growth rate increased dramatically. At the moment there are 7 billion people and in 2100 it is expected that there will be between 8.5 and 12 billion people. Currently we already overshoot the earth’s carrying capacity and this problem will become even larger in the future. Because of the global overpopulation many negative ecological and socio-economic effects occur at the moment. Land-use change, climate change, biodiversity loss, risk of epidemics, poor welfare distribution, resource scarcity and subsequent indirect effects such as factory farming and armed struggles for resources are caused by overpopulation. All these effects are long-lasting and many are irreversible. The longer we overshoot the carrying capacity of the earth and the larger the human population becomes, the worse the effects will be. It can thus be concluded that the global human population is and will probably remain too large to allow for a sustainable use of the earth’s resources and an equal distribution of the use of these resources. In order to achieve global sustainable use and an acceptable distribution of welfare, a world population of 2 billion people would be the maximum. Stabilization of the population is inevitable and therefore it is recommended to support policies to gradually reduce the population level in order to prevent self-regulatory mechanisms like catastrophic global food shortages, escalating armed conflicts about scarce resources or pandemic diseases, from happening.