"Eliminating water shortages depends on a global attempt to raise water productivity similar to the effort launched a half-century ago to raise land productivity, an initiative that has nearly tripled the world grain yield per hectare." –Lester R. Brown, World Facing Huge New Challenge on Food Front in Plan B 3.0: Mobilizing to Save Civilization
Chapter 10. Stabilizing Population by Reducing Fertility: Introduction
World population has more than doubled since 1950. Those born before 1950 are members of the first generation in history to witness such a doubling during their lifetime. Stated otherwise, more people have been added to the world's population since 1950 than during the 4 million preceding years since we first stood upright.1
Throughout most of these 4 million years, we were few—numbering only in the thousands. When agriculture began, world population was estimated at 8 million—less than a third the size of Tokyo today. After farming got under way, population growth slowly gained momentum. With the Industrial Revolution, it accelerated further. After 1950, it soared.
We are struggling to understand the dimensions of population growth over the last half-century. We can relate to 100,000 people, the number filling a large stadium for an athletic event or a concert, but relating to an annual increase of 80 million is difficult. To grasp the dimensions of this growth, we can equate it to the combined population of the United Kingdom, Belgium, Denmark, and Sweden today. As someone who spends more time than I would like in planes and airports, it is easier for me to relate population growth to the passenger capacity of a jumbo jet. It takes the world's growing population less than 3 minutes to fill a jumbo jet with 400 passengers.
Despite the stresses associated with continuing population growth, the United Nations projects that our numbers will grow from 6.1 billion in 2000 to 9.3 billion in 2050. Of even more concern, all of the 3.2 billion additional people will be added in developing countries. Given the analysis in this book, there is reason to doubt that this will actually happen. What is unclear is whether the projections will not materialize because we accelerate the shift to smaller families in time or because we fail to do so and death rates begin to rise.
Many countries that have experienced rapid population growth for several decades are showing signs of demographic fatigue. Governments struggling with the simultaneous challenge of educating growing numbers of children, creating jobs for swelling ranks of young job seekers, and dealing with the environmental effects of population growth are stretched to the limit. Without a concerted effort by national governments and the international community to shift quickly to smaller families, land scarcity and water shortages could become unmanageable—leading to political instability, economic decline, and rising death rates.
In this situation, when a major new threat arises—such as the HIV epidemic or aquifer depletion—governments often cannot cope. Problems routinely managed in industrial societies are becoming full-scale humanitarian crises in many developing ones. As the HIV epidemic continues to spread, rising death rates in some African countries will likely bring their population growth to a halt. This rise in the death rate marks a tragic new development in world demography.
The issue is not whether population growth will slow, but how. In its 1998 update of long-range population projections, the United Nations reduced the predicted population for 2050 by some 500 million. Two thirds of this reduction was due to fertility falling faster than projected. But the other one third was the result of a projected rise in death rates, largely because of HIV in Africa. For the first time in nearly half a century of world population updates, projections were being reduced by rising mortality. The challenge is to slow population growth in all developing countries by lowering birth rates, because if we fail, it will be slowed by rising death rates.2
1. All population data in this chapter, including per capita calculations and future projections, are from the United Nations, World Population Prospects: The 2000 Revision (New York: February 2001) unless otherwise noted.
2. United Nations, Long-range World Population Projections: Based on the 1998 Revision (New York: 1999).
Copyright © 2001 Earth Policy Institute