Interview: As World Population Hits 7 Billion, How Many More People Can The Earth Sustain?

A World Food Program worker walks past bags of relief food at a distribution center at a refugee camp near the Kenyan-Somali border in August.

The world's population has hit 7 billion and the rate of growth shows no sign of slowing down. RFE/RL correspondent Antoine Blua asked Gilles Pison, senior researcher at the French National Institute for Demographic Studies, about the implications for human well-being and the fate of the Earth.

RFE/RL: On October 31, the world's population is projected to reach 7 billion, and that figure is expected to rise to at least 10 billion by 2100. Such demographic pressure poses mighty challenges for easing poverty and conserving the environment, and some people are questioning whether we are too many and how large a number the Earth can sustain. What do these figures mean for human well-being and the fate of the planet?

Gilles Pison:
The world population continues to rise but at a decreasing rate year after year. Population rise reached a maximum, in terms of speed, 50 years ago. At the time, the population was increasing by more than 2 percent a year. The growth rate has since decreased by half -- it's a little more than 1 percent a year -- and it should continue to decrease in the coming years. The population may be almost stabilized in 100 years.

The challenge is to welcome an additional 1 to 4 billion [people] by 2100 while maintaining a livable planet. We don't know what the maximum capacity of the planet is. The 1 billion inhabitants who live in developed countries have been the main source of resource consumption and of global warming. So, if tomorrow's 10 billion people adopt the way of life of the Europeans or Americans, it would not be tenable for a long time.

It is illusive to think that we can impact a lot on the number of people over the next decades. However, it's possible to change our way of life to make it more economic and respectful of the environment. And this has to be done right now.

RFE/RL: The world population crossed the 6 billion mark in 1991, when there was little apparent reason to believe that the march of human progress would be slowed any time soon by population growth. The world looks very different today, with rising commodity prices, lower economic expansion, setbacks in reducing hunger and severe poverty, and deflated hopes that the pace of progress would continue unimpeded by resource limits or environmental restraints. Has the past decade given support to the Malthusians, who thought a rising population would create an age of scarcity?

Pison:
From a demographic point of view, fertility has diminished since the 1990s. Today, on average, a woman gives birth to 2.5 children, [which is] half the 1950 figure. So the size of the families continues to diminish. Economic expansion is occurring at variable speed: Asia and Latin America [have] experienced strong economic growth rates, [while] in Africa, the growth has been lower, but there was growth.

The challenge is that most demographic increase will take place in Africa. In the next 100 years, Africa's population will probably multiply by four. The countries of Africa and a number of others in Asia will still experience quick demographic growth and the challenge is to manage this increase while developing economically. It's manageable.

In some countries, very high growth rates like in sub-Saharan Africa are probably not favorable to economic development. However the population factor is probably not behind the economic slowing down observed here and there.

As for hunger, the planet globally produces enough food to nourish 7 billion people. Famines often occur [in conflict zones,] when food aid and the market are incapable of delivering food which has not been produced locally. More and more, the market and food aid allow countries which experience bad harvests not to experience a mortality increase.

RFE/RL: The solutions proposed by the United Nations Population Fund to remedy the problems linked to world population growth, such as education, family planning, and the fight against global warming -- will they be sufficient?

Pison:
Humanity is engaged in a great movement which started two centuries ago, according to which more and more families are of small size everywhere on the planet. Parents have fewer children but invest so that they have a better life than theirs. It means going to school and having a good job.

This evolution is going on everywhere. The countries' population policies can help the movement, accompany it, but are not at the origin of this movement. So there's no doubt that humanity will have its population stabilize and the reason is that couples want to have fewer children.