What ails the globe?

Top ecologist Norman Myers offers his list of the Earth's top 10 environmental problems

ORTING OUT THE GLOBE'S many environmental challenges is no easy task. Extinctions, toxic-chemical contamination, lead poisoning, garbage dumps and a myriad other images swarm across our thoughts and TV screens with kaleidoscopic disorder. How do we make sense of this welter of disturbing environmental news? And which of these issues should concern us most? To examine the priorities, International Wildlife turned to British economist and environmental expert Norman Myers. His charge: Compile his personal list of the Earth's 10 most pressing environmental problems.
Myers is well equipped for such a task. A consultant to governments and international agencies, he won the Volvo Environment Prize in 1992, the largest monetary award of its kind outside the United States. He is also author of numerous environmental books including, most recently, Ultimate Security (W.W. Norton, 1993), which outlines the growing social impact of environmental breakdowns.
Here, from Myers' extensive files, is his list, complete with explanations, solutions and various related commentary.

1 Global Warming

It affects more people in more ways than any other problem; indeed, it will affect virtually everyone. Global warming occurs as pollutants such as carbon dioxide, a by-product of the burning of wood and of fossil fuels such as oil and coal, accumulate in the atmosphere, forming a gaseous blanket around the globe. This blanket holds in a portion of the sun's warmth that normally would radiate back into space. Because the gases act like the glass roof and sides of a greenhouse, this is often called the greenhouse effect.
According to the United Nations' Intergovernmental Panel on Climate Change, comprised of hundreds of topflight climatologists, present trends in greenhouse-gas emissions will increase the planet's average temperature by roughly 2.5 degrees Centigrade by the middle of the next century, if not before.
A 2.5 degree rise might not sound like much, but as U.S. Vice President Albert Gore recently pointed out, a 4-degree shift the other way during the last ice age meant the difference between having a nice day and finding a mile of ice on your head.
Solution: First and foremost, get off our fossil-fuel binge. We shall have to do that soonish as concerns oil anyway, since they ain't making any more of it. By weaning ourselves from fossil fuels, we can cut back on carbon dioxide, the greenhouse gas that accounts for half of global warming, and do our economies a power of good.
Since the mid-1970s, Americans have practiced enough energy conservation to save $150 billion a year, equivalent to half the federal deficit and worth $600 per citizen. They could double that amount merely by exploiting existing technologies.
New droughts
Certain regions look likely to experience both higher temperatures and lower rainfall - a sure-fire recipe for unending droughts of unprecedented severity. They feature several of the main bread-baskets of the world, and by the middle of the next century we shall have nearly twice as many people to feed.

Evidence For Global Warming
1. Greenhouse gases, particularly carbon dioxide, hold in heat, and the amount of greenhouse gases has risen since the Industrial Revolution. Prior to the Industrial Revolution, carbon dioxide concentrate in the atmosphere stood at 280 parts per million. Today it measures more than 350 parts per million.
2. Experts concluded in a 1992 report that global warming must be on its way if only because of the carbon dioxide and other greenhouse gases that we have been kicking into the global skies during the past industrialized century. We keep on spewing effluents in ever-greater amounts.
3. Since 1980 we have had eight of the ten hottest years on record. Is the globe trying to tell us something?

2 Biodepletion

This is the mass extinction of species throughout the globe. We seem set to eliminate between one-third and two-thirds of Earth's species, plus a similar proportion of subspecies. It will be the biggest extinction spasm since the demise of the dinosaurs and associated creatures 65 million years ago. The result: a massive draining of the planetary gene pool.
Wild species and their genetic resources make many contributions to our daily welfare by providing products used in medicine and agriculture. The National Cancer Institute estimates that at least a dozen plant species in tropical forests possess the capacity to generate superstar drugs against various types of cancer. Such valuable resources should be protected, but we are losing several plant species in the forests every day.
Peter Principe, an economist with the U.S. Environmental Protection Agency, says that the cumulative market value of plant-based drugs in developed nations up to the year 2000 is an estimated $500 billion (in 1984 dollars).
Solution: In the short term, we need to establish many moreparks and reserves, especially in the developing tropics. This is only an interim solution to a more cohesive attempt to protect the biosphere, because we know that even if we were to turn the whole of Amazonia into one huge park and build a fence around it 50 meters high, it still would not be protected from multitudes of landless peasants, nor from acid rain and global warming. Jeff McNeely, one of the most innovative scientists at the International Union for Conservation of Nature and Natural Resources-The World Conservation Union, says that 50 years from now we may find that very few parks exist, either because they have been overrun by land-hungry farmers and climate upheavals, or because we have found a way to manage our landscapes in a manner that automatically leaves room for wildlands and their biodiversity.
In the long term, the only way to save biodiversity is by saving the biosphere - for us humans as well as for our fellow species.
The minimum length of time it will take evolution to come up with a replacement stock of species to match today's stock: 5 million years.

We are effectively saying that people of the future can get by without the lost species. Suppose the sustainable global population of the net 5 million years is 2.5 billion people, less than half today's total. This means that people alive today are making a decision on the unconsulted behalf of the 100 trillion people who will come after them (If you have trouble imagining a figure of that size, ask yourself how longis one trillion seconds; answer 32,000 years.)

3 Consumption

The amount of minerals used by Americans since 1940 equals the amount consumed by all humankind prior to 1940. People dump 70,000 synthetic chemicals into the environment annually, after only minimal testing against only a few recognized threats. In 1987, the United States released 1.2 million tons of toxic chemicals into the atmosphere, 670,000 tons into the soil and 250,000 tons into water bodies, plus 1.4 million tons into landfills and public sewers.
Rich nations account for a quarter of the world's human population but consume three-quarters of the world's natural resources and generate three-quarters of its waste and pollution.
Most developed nations are experiencing some population growth, albeit at a much lower level than that of developing nations. For example, Great Britain is increasing at only a twelfth the rate of Bangladesh. But, because each Briton consumes 30 times more commercial energy than a Bangladeshi, British population growth contributes 3.9 times as much carbon dioxide to the global atmosphere and hence contributes more to global warming. Ironically, unplanned births account for all of Britain's population growth. The effective size of the average American family in terms of per capita pollution and consumption of critical resources is the equivalent of 30 citizens of the developing world.
Solution: Recycle like crazy. The United States recycles a little more than half as much paper as does Japan. Germany requires companies to take back packaging supplied with their products.
A U.S. company, 3M Corporation, shows the way: Since 1975 it has saved $1.2 billion by recycling waste and preventing pollution. Recycling could be an economic boom for the U.S. economy, with a potential for growing from a $50 billion-a-year industry in 1989 to a $200-billion-a-year industry in 2000.
We also need to put a priority on eliminating pollution. Right now, in nations that show concern about pollution, priorities are often backwards. For example, the United States spends $9 billion a year on contamination cleanup but only $200 million yearly to prevent contamination in the first place.
Fuel Frugality
The U.S. economy could run on half of the fossil-fuel energy used today, possibly less. Amory Lovins of the Rocky Mountain Institute, a nonprofit group that studies resource use, says, "Our industrial performance will leap ahead, our pollution flows will decline (so will our monthly bills), and our showers will still be hot and our beer cold.

4 Population

So many people, so few resources.
It took 10,000 lifetimes for the world's population to reach two billion people. Now, in the course of a single lifetime, world population is increasing to three times that figure. Within another lifetime it may double again.
Nine out of ten new arrivals are in developing nations. A British population expert, Paul Harrison, has calculated that this population growth caused 79 percent of the tropical deforestation that occurred from 1973 to 1988, leading to tens of thousands of species extinctions during each of those years. Harrison also declares that population growth accounted for 69 percent of the increase in livestock numbers that occurred from 1961 to 1985, resulting in widespread soil erosion and desertification from overgrazing. The growth also underlay the 46 percent rise in carbon dioxide emissions from fossil fuels from 1960 to 1988.
Providing food for a growing human population is another problem. Some analysts protest that agrotechnology will keep on expanding the Earth's ability to feed people. But consider: From 1950 to 1984, we achieved a 161 percent increase in world grain output, while since 1985 we have managed only a 6 percent annual increase. Moreover, today's harvests are only a little higher than those of 1985, yet we have an extra 700 million people to feed. While world population has increased by 14 percent, grain output per person has declined by 9 percent since 1985.
Fortunately, future population growth is only a projection of recent trends, and we can alter those trends. Demography is not destiny. For example, Thailand's average family size in 1969 stood at 6.5 children; in 1989 it was two children. Even in India, where the average family size of almost four children has seen little change for years, Kerala State has achieved replacement level fertility.
Solution: Fully 300 million couples in developing countries want to practice family planning, but they lack the means to do it. We of the developed world, through financial support, must help these people to meet their goals so we can cut the future global population by more than 2 billion. We also need to help upgrade the status of women in the developing world by funding projects that will put these women into school, win them jobs and enhance their social standing. Such measures usually result in smaller family size.

Calculations of the World Hunger Project

Total world population today:
5.5 billion

Number of people on a vegetarian diet that the Earth can sustainably support with present agrotechnologies and equal distribution of food supplies:
5.5 billion

Number of people that the world can support on a diet deriving 15 percent of calories from meat and milk products, as do many people in South America:
3.7 billion

Number of people that the world can support on a diet deriving 25 percent of calories from animal protein, as is the case with most people in North America:
2.6 billion

5 Third World Poverty

At least half the Third World's environmental problems, such as deforestation, desertification and soil erosion, is caused by one-quarter of the population of developing nations. These are the "bottom billion" people who live on a cash income of a dollar a day. At least 400 million of them are so impoverished that they are chronically undernourished - in plain language, semi-starving. Bypassed by development, these "marginal" people see no alternative but to scratch a living from marginal environments - those too wet, too dry or too steep for normal agriculture. They wreak fearsome damage in their efforts to keep body and soul together.
Their numbers are growing. They have the biggest families by far, because they think of children as an economic measure: more hands to help with farm work. Having many children also helps to ensure that enough survive to support parents in old age.
Solution: If rich nations were to open their markets to exports from the developing world, as they do to one another's exports, Third World revenues would skyrocket by $lOO billion yearly, twice as much as all foreign aid presently offers. Ending Third World poverty would in turn strengthen the global economy because developing nations would offer many new markets.


When poor people torch Amazonia and Borneo, the greenhouse gasses will disrupt climate worldwide. When they turn grasslands into deserts, the climatic dislocations could again reach around the globe. Isn't Third World poverty something none of us can afford? There's some sense to the notion that by taking care of people, we help take care of the population problem.

Proportion of U.S. citizens to citizens of all other nations:

Proportion of U.S. pollution to global pollution:

Amount of junk discarded yearly by the average American, as a percentage of body weight:
What's the Good Life?
Does the good life really consist of accumulating ever-more goodies? How many people on their death beds ever say they wish they had lived higher on the hog?

6 Soil Erosion

Wind and storm-water runoff carry away about 25 billion tons of topsoil yearly, worldwide. At this rate, by the middle of the next century we shall have lost virtually all our topsoil, and no substitute for soil exists.
Erosion occurs even in the world's most prosperous nations. It is as bad in parts of Indiana, one of America's agricultural states, as in India. Loss of soil in the United States leads to loss of farmland fertility; this and other on-farm costs from erosion amount to $18 billion a year. Off-farm costs, such as disruption of downstream water systems, are worth another $10 billion a year. That amounts to almost three-quarters the value of America's $42-million corn crop.
Solution: Instead of effectively fostering erosion through agricultural subsidies that encourage overuse of farmlands, nations with serious erosion problems could adopt a U.S. approach, offering economic incentives to farmers who protect topsoil. Result of the U.S. program: Erosion dropped by a third between 1985 and 1990 and may do the same again by 1995.
Developing nations with hilly terrain and heavy rainfall should work to ensure that watersheds retain tree cover. Trees can reduce flooding and supply renewable stocks of timber and fuelwood. Impoverished Ethiopia has found it worthwhile to build more than a million kilometers (670,000 mi.) of anti-erosion terraces and bunds to safeguard steeply sloping croplands, though even that fine effort helps a mere 6 percent of threatened highland areas.
Dirty Deal
The topsoil the world loses every year theoretically could grow 9 million tons of grain, enough to feed 200 million undernourished people or half of all the semi-starving on Earth.

7 Water Shortages

One of the main sources of water for drinking and crop irrigation worldwide is underground aquifers. This is water that has accumulated in vast caverns and in porous sediments for thousands of years, seeping in from the planet's surface. This source of water is used even in areas of heavy rainfall, such as Florida. The U.S. farming regions in the Midwest draw water from aquifers 10 to 50 times faster than nature replaces it. China is also mining its water, meeting the needs of China's billion residents with aquifers that can sustain only 650 million people.
Agricultural irrigation produces a third of our food from a sixthof our croplands. In the future, we will need to grow three times as much food if we are to take care of population growth and increase nutritional levels.
Solution: All nations need to protect their sources of fresh water and to safeguard water quality and aquatic ecosystems. Industry should encourage the development of water-saving devices, and water-use plans should highlight the need to minimize waste. In some nations, for example the United States, government so heavily subsidizes water that incentive to use it sparingly and efficiently is scant.


If Earth were the size of an egg, the size of the total volume of water would be about one drop. Of this total, only about one-third is actually available to humans as fresh water for drinking and irrigating (water in lakes, rivers, and the accessible water table below ground). Source: The Cousteau Almanac.

Sick, Sick, Sick
The economic cost through workdays lost to sickness in the developing world is reckoned to be $125 billion a year, or roughly 10 percent of the economies in question.
Running out
In the United States, farmers are taking water from the Ogallala aquifer underlying the great wheat states at rates averaging 40 times that of natural replenishment.
Thirst Quenching
Providing clean water to the globe would be a prime means for cutting child deaths in the Third World, presently equivalent to a jumbo-jet load of children every quarter hour. During the 1990s we could save 100 million children.

Amount of money it would take to supply clean water to all people:
$36 billion per year.
Amount the world spends on military activities:
$36 billion every two weeks.

The daily amount of water available per person for basic household needs in the developing world as a proportion of the amount of water an American uses each time he or she flushes the toilet:

Number of people who suffer water shortages today: more than 1 billion
Number of people expected to suffer such shortages 20 years from now:
3 billion

Diseases caused by water shortages:
150 million cases of schisstosomiasis, 200 million cases of diarrhea, 300 million cases of roundworm

8 Ozone Depletion

Ozone is an atmospheric oxygen compound that shields the Earthfrom lethal solar rays. The release into the atmosphere of chemical compounds containing chlorine - including coolants used in refrigerators and air conditioners - is destroying the atmospheric ozone layer because escaping chlorine molecules combine with the ozone to form acid compounds.
Data accumulated during the past decade have led a United Nations panel of several hundred leading climatologists to the unanimous conclusion that ozone depletion poses a grave threat to many living creatures, including people. The experts differ among themselves only on the amount and rate of ozone loss - and time after time they have found it is worse than expected. In 1992, ozone loss in temperate regions, including North America and Europe, turned out to be twice as great as expected. In 1993, the U.S. National Aeronautics and Space Administration reported that ozone depletion over North America was the worst on record. Even if production of the chief ozone-destroying chemicals ends, the chemicals already in the atmosphere will continue to destroy ozone molecules for at least 60 years.
Solution: The best solution is to put an end to the chemical culprits immediately. Unfortunately, most producer nations are deferring final phaseout until the end of 1995. However, some producers of the chemicals have voluntarily stopped production, and the ozone layer already shows signs of recovering. Some possibly better news: In summer 1993, scientists were surprised to find a sudden slowdown in the accumulation of ozone-depleting chemicals in the atmosphere.
Most of the world's governments have agreed to phase out the destructive chemicals by the end of the century. If the phaseout is completed, the ozone layer should begin to recover within a few decades. But emergent industrial powers such as China and India, seeking to install refrigerators in every home, may continue to use cheap, ozone-depleting refrigerants. They are asking for technical and economic help to avoid this, and it is in the developed world's interest to provide all the assistance possible.


Without the planned phaseout of the harmful chemicals the United States alone could eventually suffer an additional 350 million cases of skin cancer and tens of millions of additional cases of eye cataracts. Just the first could entail economic costs reckoned at $40 trillion, while prevention would cost $36 billion. There would also be suppression of immune systems, with great increase in infectious diseases.
These health damages would be compounded by ecological injury to major crop plants. Scientists have tested some 200 plant species, most of them crops, and have found that two-thirds are harmed by increased ultraviolet radiation through ozone-layer depletion.
Sizable damage also could occur to marine fisheries. In the Antarctic Ocean, located beneath the atmosphere's biggest ozone "hole" and the site of one of the world's most bountiful fisheries, the productivity of phytoplankton - tiny plants that form the basis of marine food chains - has already been reduced by 6 to 12 percent.

9 Synergisms

"Synergism" is the interaction of two or more processes in such a way that the total effect of the combined processes is greater than the sum of the individual effects. For example, if low sunlight reduces a plant's photosynthesis, the plant becomes more susceptible to the effects of cold weather; similarly, cold weather may increase the plant's vulnerability to low sunlight. In this case, the compounded effect is greater than the total effect produced by the separate low-light and cold-weather impacts simply added together. In some cases, the compounded impact, or synergism, can be 10 times greater than the sum of the component parts.
When we consider all environmental disruptions together, we find a multitude of potential synergies that may have a deeply impoverishing impact upon us. If this is so, we should expect an environmental debacle both greater and sooner than most data predict based on studies examining only individual environmental threats.
Solution: We need an intensive scientific effort to investigate synergisms in their full scope. If we fail to anticipate the synergisms that lie ahead, our best efforts to tackle environmental problems may fall far short.
At the same time, environmental safeguards can offer constructive synergisms. For example, tree planting in the humid tropics, undertaken to generate a sink for atmospheric carbon to counter global warming, could supply many spinoff benefits, including commercial plantations that will reduce logging on remaining natural forests. In addition, reduced deforestation would help preserve the abundant stocks of species in tropical forests. And, both tree plantations and surviving natural forests in upland catchments would regulate downstream water flows and thus reduce flood-and-drought cycles.
We know all too little about environmental synergisms. If we could better predict potential synergisms in the environmental upheavals that lie ahead we would be better able to anticipate, and even prevent, some of their adverse repercussions.
Consider, for example, the synergism of ozone-layer depletion and global warming. Marine phytoplankton, which are important absorbers of carbon dioxide, are exceptionally sensitive to ultraviolet radiation, which ozone depletion intensifies. Were marine phytoplankton to be markedly reduced, the ocean's capacity to serve as Earth's leading "sink" of carbon dioxide would decline significantly, thus accelerating greenhouse-effect processes. Conversely, ozone-layer depletion cools the stratosphere, which could increase global warming in the lower atmosphere.

10 Unknown Unknowns

Amongst all the uncertainty about our world, we can be all but sure that some unrecognized environmental processes have the capacity to generate major environmental problems in the future. Because we know next to nothing about these processes, I call them "unknown unknowns."
The name might seem a contradiction in terms. How can we know what wedo not know? But consider: While we know all too little about global warming, and still less about when it will arrive in full scope and with what regional variations, we do know for all intents and purposes that it is on its way. It is a "known unknown." Until recently, however, we hardly knew of its very existence: It was an unknown unknown.
As we impose multitudes of further assaults on the Earth, what new unknown unknowns are working up momentum in our environments, waiting to leap out on us at some stage of the future? The question surely ranks among our most difficult environmental challenges, yet it receives next to no attention. We need to initiate investigations into the workings of our planet, to go boldly, as it were, where no scientist has gone before. We need to troubleshoot the planet, looking for pings and dings that we do not yet know are there.
Solution: Mount a sizable scientific program to tackle the challenge. Regrettably, not all scientists are inclined to invest time and effort on taking shots in the dark, but those willing to accept the challenge need full financial support. More important, we should throttle back on the myriad insults we impose on our one and only Earth. But we know that anyway. Or do we?
Acid rain did not appear on our radar screens during the decades that it was building up unseen and unsuspected. Our unknowing has been costly: Europe's forests may suffer annual damage worth $30 billion for decades. Nor did we suppose there could be anything amiss with the ozone layer until, after many years of chemical attack, its thinning became all too apparent.