1.4 World Population and Associated Impacts

Real life situations follow the pattern of exponential growth. The most familiar of the these is the world population graph, which you have probably seen before:

Figure 1.4.1 World Population since 1850

Source Menninger [see reference 4]

Figure 1.4.1 sourced from Slideshare.net (Author: Toni Menninger) under a creative commons attribution-non commercial license
http://www.slideshare.net/amenning/growth-in-a-finite-world-sustainability-and-the-exponential-function    

Global population has just reached 7 billion people. 100 years ago there were about 1.6 billion people in the world and in the 1960's there were about half the people there are today. In the last 50 years the population has doubled, and this trend shows no signs of changing. Each person on the world requires resources to survive so naturally there will follow exponential graphs for world resource use over the same time period.

Although a bigger population generally means more mouths to feed, there is not an even distribution of consumption patterns throughout the world. One of the biggest indicators of unsustainability is in the misdistribution of wealth. Over a third of the world still live in poverty with limited access to energy, water or food.

In 2006, a team of scholars with the United Nations University’s World Institute for Development Economics Research published the first paper to tally, for the entire world, all the major elements of household wealth, everything from financial assets and debts to land, homes, and other tangible property.

This research, based on year 2000 data, found that the richest 1 percent of the world’s adult population, individuals worth at least $514,512, owned 39.9 percent of the world’s household wealth, a total greater than the wealth of the world’s poorest 95 percent, those adults worth under $150,145 who hold, together, just 29.4 percent of the world’s wealth. [see reference 5]

Personal wealth is distributed so unevenly across the world that the richest two per cent of adults own more than 50 per cent of the world’s assets while the poorest half hold only 1 per cent of wealth [see reference 5]. The USA consumes 25% of the world's energy with a share of the world population of 4.5% [see reference 6]. The figures for material, water and food consumption between the richest nations and the poorest display a similar level of disparity.

Population growth is much higher in developing countries, while resource consumption and pollution is higher in developed countries. The gap between the ends of the spectrum have been increasing in a similar exponential fashion.

The focus of sustainability is as much on humanity (the social corner of the sustainability triangle) as it is on nature (the ecological), and to reduce this inequality and provide a basic standard of living conditions for the earth's inhabitants is paramount to the sustainability challenge.