A Sustainable World

From the Foundation's 1994 Annual Report

[Photo of Bat star at low tide]
Half-way through the last decade of this millennium, human society appears set on a course that will test the very nature of its relationship to the planet.

Our population expands inexorably. Resource extraction and its incumbent impacts accelerate. Pollution grows in volume, and in risk created. According to scientists, we may soon confirm that the Earth's capacity to absorb these assaults is finite -- learn not by theory or calculation but through our own arduous experience. The consequences for people and indeed for the wealth of life on earth will be challenging, at best. Even without fulfilling the direst of predictions the result may erode severely the bases of human well-being.

Why are we in this predicament? First, there is magnitude: human activities have grown to a scale where we now have measurable impacts on global processes. Second, there is ignorance: we appreciate only dimly the complex dynamics of global ecosystems, even after the remarkable advances in science that have taken place during this century. Third are the time-lags: years may intervene before we discover the full consequences of our activities. Indeed, the effects may play out over decades.

Nothing illustrates these points more clearly than the effect of chlorofluorocarbons, or CFCs, on stratospheric ozone. The machinery of modern industrial chemistry produced CFCs in ever increasing volume during the decades between their invention and the scientific verdict that found them guilty. Little did anyone imagine that these "safest of chemicals" were undermining a key component of the earth’s life support system.

Thomas Midgely first synthesized CFCs in 1928. Quite independently, that next year W.P. Goetz began a series of experiments in which he discovered stratospheric ozone's role in protecting the earth from ultraviolet radiation. The possibility of a link between the two was beyond imagination. In 1941, Midgely won the highest prize in American chemistry for his pioneering work. Even then, the likelihood that concentrations of any synthetic gas might be building in the stratosphere and might pose a risk to the planetary radiation shield was not under remote consideration. At the ceremony Midgely went so far as to inhale vaporized CFC and then blow out a candle with CFC-laden breath, demonstrating their safety, he claimed, with theatrical finality. Only in 1970 did strong evidence emerge that CFCs had spread throughout the atmosphere. Then in 1974, at a time when CFCs had been on the market for more than 40 years, scientists calculated a theoretical threat to stratospheric ozone. Derided by industry at first, this prediction was later confirmed in the 1980s with the discovery of a massive "ozone hole" over Antarctica.

The CFCs' story may end happily, if international resolve to eliminate their production and use holds steady against what is now a dismaying and blatant misrepresentation of science. The dynamics of atmospheric chemistry will allow for recovery; it was caught soon enough even with the time-lag. And industrial concerns joined in the effort, finding substitutes with less damaging impacts. Thus, while ozone depletion will continue into the next millennium, its pace will slow and the ozone shield will gradually rebuild.

This same story has many variants. Some involve other synthetic chemicals whose production reached enormous scale before we became aware of the consequences. Today, for example, every person on the planet bears a burden of polychlorinated biphenyls, or PCBs, some at health-threatening levels. Likewise the infamous DDT: even today new health impacts of DDT are being discovered, effects perhaps more dangerous than those that led to dramatic restrictions on its use in the 1970s. The persistent nature of these and related chemicals means that their impacts will be felt for generations.

But these variants go beyond case after case of synthetic chemical or toxic contaminants. At their most vexing, they involve the impact of everyday human life, magnified by the 5-plus billion of us that inhabit the planet -- impacts scaled up so abundantly that they are no longer benign or inconsequential at a global scale.

Consider carbon dioxide. This gas, exhaled with each breath we release, exists as a "trace gas" in the natural atmosphere. In animals it is a normal byproduct of metabolism. It is also produced by people engaged in daily life, especially when deriving energy from fossil fuels. As early as the late 1800s, chemists speculated that the Industrial Revolution fueled by coal and oil might increase atmospheric carbon dioxide enough to alter the planet's temperature. Now, as anticipated, human-made carbon dioxide is altering the atmospheric balance from sources as large as coal-fired power plants and as small but ubiquitous as individual cars. And as predicted, average global temperatures are rising. As predicted, extreme climatic events are becoming more common. As predicted, sea level is rising.

These predictions and their confirming measurements have become immensely sophisticated, each year incorporating greater detail and new understandings of atmospheric physics. In 1994, their advances shed new light on how different patterns of pollution interact to affect atmospheric temperature. Through the greenhouse effect, carbon dioxide causes global temperatures to rise. But scientists were perplexed by the fact that the observed rise was not as great as the rise predicted. This deviation was seized upon by skeptics who asserted that because the increase was small compared to the predicted rise global warming, if real at all, would be minimal.

Scientists achieved a breakthrough in this argument when they incorporated other pollutants, especially sulfate particles, into the computer models. They discovered that these air-borne pollutants were acting as a shield, cutting down on the amount of incoming sunlight, at least in the most polluted regions. When this effect was incorporated into the computer models, the predicted global warming dropped to match the observed. The scientists found that by including past patterns of sulfate production in their calculations, they could reproduce all of the major trends in global temperature since the mid-1800s.

Their analyses suggested that industrialization's first impact was local atmospheric cooling, resulting from large-scale release of sulfate particles into the air. Over time, however, the same industrial activities produced ever more carbon dioxide which, because of the slower-starting but larger greenhouse effect, ultimately overcame the sulfate cooling to heat the earth and destabilize the climate. Here, as with CFCs, time-lags confuse the picture. As with CFCs and other contaminants, the time-lags also mean that preventative action must come long before the impacts are realized because by then it will be too late to avoid catastrophic disruptions.

The needed cutbacks will be difficult but not impossible. They will require major advances in making energy use more efficient. They will demand large shifts to renewable energy -- from the sun, from wind, from biomass -- and to new, cost-efficient technologies for decreasing carbon emissions from uses of fossil fuels. They will require leveling the playing field of financial incentives that currently provide immense comparative subsidies for fossil and nuclear energy. They will take time -- decades at a minimum -- and because of time-lags some amount of climatic disruption may be inevitable. But this problem, like that created by CFCs, can be reversed.

Not so the loss of biological diversity, at least within the likely course of human existence. Biodiversity lost cannot be recovered. Evolution may create new diversity over time, but this time scale is measured in millions of years, and the life forms that arise from that process will almost certainly differ from those that inhabit the earth today. The extinctions now underway will affect all succeeding human generations.

The loss of biodiversity, like the carbon problem, results from the daily cumulative effect of the human enterprise. It spreads far and wide across forests and prairies, wetlands and desert, tundra and reef, to virtually every region on earth. For the most part, it is caused one acre at a time as human needs, aspirations and, sometimes, greed combine to gnaw away at habitats essential for life. Ultimately, it is fraught with irony, for as we contribute to the elimination of habitat, the degradation of ecosystems and the extinction of species, we diminish our own prosperity and future.

Scientific advances in 1994 reveal that time-lags are important for biodiversity loss as well. These delays are of two quite different types. One involves the gradual release of synthetic chemicals, especially persistent organochlorine pollutants, into the global ecosystem. Decades after their initial release, these compounds are still working their ways through food chains and along different distribution pathways. The general trends are threefold: into the oceans; toward colder regions -- up mountains and toward the poles -- because of cycles in which the compounds evaporate and then condense; and to the highest levels of the food chain via the process known as "bioaccumulation." This puts high latitude marine mammals and other fish-eaters, including people, at greatest risk. Widespread marine mammal die-offs in the late 1980s are now understood to be a result of the cumulative impact of pollutants undermining the immune systems of seals and dolphins. Experiments show, for example, that the very same herring sold in some fish markets in Europe will weaken seals' ability to resist disease.

The second time-lag is part of the extinction process caused by habitat destruction. Extinction rarely waits until elimination of the very last patch of habitat. It occurs at some time interval past the moment when the remaining habitat is no longer able to support a viable population. As the habitat of a healthy species is gradually destroyed and its land (or sea) base is eroded, the species passes a threshold. Individuals remain -- they may even be reproducing -- but their long-term fate has been sealed. Thus, a time-lag separates the point at which extinction becomes a certainty and the moment the last individual disappears.

How many of today’s species are caught in this time-lag, present now but already fated for extinction? How many more may be drawn in if current trends continue? Neither question can be answered with precision. Scientific specialists in the field are convinced, however, that the numbers are large and profoundly troubling to human well-being. Our fate is inextricably intertwined with other life on the planet and the ecosystems that are the sum of its collective parts.

These issues -- debilitating patterns of contamination, climatic instability, the loss of biodiversity -- are parts of the test that we have now put to the planet. Where are the limits? It is worth remembering that we are all engaged in this test, together. We are its implementors and its subjects. No one can opt out, for the test reaches to every corner of the globe. Such is the current scale of human activity.

How wise is this test? Consider the panels that exist in every university and state college and hospital in the United States, panels charged with weighing the ethics of experiments on humans and animals. Not one of these panels would pass favorable judgment on the global experiment in which we are now engaged. Yet we march on, almost unimpeded, undaunted by what we have already begun to experience.

The Foundation supports efforts to understand and solve these central problems.

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