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INTERNATIONAL CONFERENCE ON POPULATION
AND DEVELOPMENT Cairo, 5 - 13 September 1994 TOO
MANY RICH PEOPLE : Weighing Relative
Burdens on the Planet by Paul Ehrlich
Concern about population problems among citizens of rich
countries generally focuses on rapid population growth in most poor nations.
But the impact of humanity on Earth's life support systems is not just
determined by the number of people alive on the planet. It also depends on how
those people behave. When this is considered, an entirely different picture
emerges: the main population problem is in wealthy countries. There are, in
fact, too many rich people.
The amount of resources each person consumes, and the damage
done by the technologies used to supply them, need to be taken as much into
account as the size of the population. In theory, the three factors should be
multiplied together to obtain an accurate measurement of the impact on the
planet*. Unhappily, Governments do not keep statistics that allow the
consumption and technology factors to be readily measuredso scientists
substitute per capita energy consumption to give a measure of the effect each
person has on the environment.
USING AND CONSUMING
In traditional societiesmore or less in balance with
their environmentsthat damage may be self-repairing. Wood cut for fires
or structures regrows, soaking up the carbon dioxide produced when it was
burned. Water extracted from streams is replaced by rainfall. Soils in fields
are regenerated with the help of crop residues and animal manures. Wastes are
broken down and reconverted into nutrients by the decomposer organisms of
natural ecosystems.
At the other end of the spectrum, paving over fields and
forests with concrete and asphalt, mining the coal and iron necessary for steel
production with all its associated land degradation, and building and operating
automobiles, trains and aeroplanes that spew pollutants into the atmosphere,
are all energy-intensive processes. So are drilling for and transporting oil
and gas, producing plastics, manufacturing chemicals (from DDT and synthetic
nitrogen fertilizers to chlorofluorocarbons and laundry detergents) and
building power plants and dams. Industrialized agriculture uses enormous
amounts of energyfor ploughing, planting, fertilizing and controlling
weeds and insect pests and for harvesting, processing, shipping, packing,
storing and selling foods. So does industrialized forestry for timber and paper
production.
PAYING THE PRICE
Incidents such as Chernobyl and oil spills are among the
environmental prices paid for mobilizing commercial energyand soil
erosion, desertification, acid rain, global warming, destruction of the ozone
layer and the toxification of the entire planet are among the costs of using
it.
In all, humanity's high-energy activities amount to a
large-scale attack on the integrity of Earth's ecosystems and the critical
services they provide. These include control of the mix of gases in the
atmosphere (and thus of the climate); running of the hydrologic cycle which
brings us dependable flows of fresh water; generation and maintenance of
fertile soils; disposal of wastes; recycling of the nutrients essential to
agriculture and forestry; control of the vast majority of potential crop pests;
pollination of many crops; provision of food from the sea; and maintenance of a
vast genetic library from which humanity has already withdrawn the very basis
of civilization in the form of crops and domestic animals.
THE RELATIVE IMPACT
The average rich-nation citizen used 7.4 kilowatts (kW) of
energy in 1990a continuous flow of energy equivalent to that powering 74
100-watt lightbulbs. The average citizen of a poor nation, by contrast, used
only 1 kW. There were 1.2 billion people in the rich nations, so their total
environmental impact, as measured by energy use, was 1.2 billion x 7.4 kW, or
8.9 terawatts (TW)8.9 trillion watts. Some 4.1 billion people lived in
poor nations in 1990, hence their total impact (at 1 kW a head) was 4.1 TW.
The relatively small population of rich people therefore
accounts for roughly two-thirds of global environmental destruction, as
measured by energy use. From this perspective, the most important population
problem is overpopulation in the industrialized nations.
The United States poses the most serious threat of all to
human life support systems. It has a gigantic population, the third largest on
Earth, more than a quarter of a billion people. Americans are superconsumers,
and use inefficient technologies to feed their appetites. Each, on average,
uses 11 kW of energy, twice as much as the average Japanese, more than three
times as much as the average Spaniard, and over 100 times as much as an average
Bangladeshi. Clearly, achieving an average family size of 1.5 children in the
United States (which would still be larger than the 1.3 child average in Spain)
would benefit the world much more than a similar success in Bangladesh.
CLOSING THE GAP
Professor John P. Holdren of the University of California
has generated an "optimistic" scenario for solving the population-
resource-environment predicament. This envisages population growth halted at 10
billion a century from now, and rich nations reducing their energy consumption
to 3 kW a head. His population target is feasible with modest effort, and the
reduction in energy consumption could be achieved with technologies already in
handgiven the necessary political willand would produce an increase
in the quality of life. This would provide room for needed economic growth in
poor nations, which could triple their per-person energy use to 3 kW. Thus the
gap between rich and poor nations would be closed, while the total world impact
would increase from 13 TW to 30 TW (10 billion x 3 kW).
Will the environment a century hence be able to support 2.3
times as much activity as today? It's questionable, but perhaps with care it
could, at least temporarily. Success would require a degree of cooperation,
care for our fellow human beings, and respect for the environment that are
nowhere evident now. But society has shown it can change rapidly when the time
is ripe; let us hope that the United Nations International Conference on
Population and Development will help ripen the time.
* The relationship is summarized in the classic I=PAT
identity: Impact is equal to Population size, multiplied by per capita
consumption (Affluence), in turn multiplied by a measure of the damage done by
the Technologies chosen to supply each unit of consumption.
Mr. Paul R. Ehrlich is Bing Professor of Population Studies
and Professor of Biological Sciences at Stanford University in the United
States. His most recent books, both co-authored with his wife Anne, are "The
Population Explosion" (Simon and Schuster, 1990) and "Healing the Planet"
(Addison-Wesley, 1991). The feature originally appeared in Vol. 6, No.3, 1994
of "Our Planet". The views expressed herein do not necessarily reflect those of
UNEP.
UNEP Feature 1994/8
« It is the consumers of the rich nations
of the temperate northern regions of the world who are primarily responsible
for the ongoing loss of natural wealth in the tropics » said
Jonathan Loh,
editor of the Living Planet Report. |