Nature, we believe, takes forever. It moves with infinite slowness through the many periods of its history, whose names we can dimly recall from high-school biology—the Cambrian, the Devonian, the Triassic, the Cretaceous, the Pleistocene. At least since Darwin, nature writers have taken pains to stress the incomprehensible length of this path. “So slowly, oh, so slowly, have the great changes been brought about,” John Burroughs wrote in 1912. “The Orientals try to get a hint of eternity by saying that when the Himalayas have been ground to powder by allowing a gauze veil to float against them once in a thousand years, eternity will only have just begun. Our mountains have been pulverized by a process almost as slow.” We have been told that man’s tenure is as a minute to the earth’s day, but it is that vast day that has lodged in our minds. The age of the trilobites began six hundred million years ago. The dinosaurs lived for a hundred and fifty million years. Since even a million years is utterly unfathomable, the message is: Nothing happens quickly. Change takes unimaginable—“geologic”—time.
This idea about time is essentially misleading, for the world as we know it, the world with human beings formed into some sort of civilization, is of quite comprehensible duration. People began to collect in a rudimentary society in the north of Mesopotamia some twelve thousand years ago. Using twenty-five years as a generation, that is four hundred and eighty generations ago. Sitting here at my desk, I can think back five generations—I have photographs of four. That is, I can think back one-ninety-sixth of the way to the start of civilization. A skilled genealogist could easily get me one fiftieth of the distance back. And I can conceive of how most of those forebears lived. From the work of archeologists and from accounts like those in the Bible I have some sense of daily life at least as far back as the time of the Pharaohs, which is almost half the way. Three hundred and twenty generations ago, Jericho was a walled city of three thousand souls. Three hundred and twenty is a large number, but not in the way that six hundred million is a large number, not inscrutably large. And within those twelve thousand years of civilization time is not uniform. The world as we really know it dates back to the Renaissance. The world as we really know it dates back to the Industrial Revolution. The world as we feel comfortable in it dates back to perhaps 1945.
In other words, our sense of an unlimited future, which is drawn from that apparently bottomless well of the past, is a delusion. True, evolution, grinding on ever so slowly, has taken billions of years to create us from slime, but that does not mean that time always moves so ponderously. Over a lifetime or a decade or a year, big and impersonal and dramatic changes can take place. We have accepted the idea that continents can drift in the course of aeons, or that continents can die in a nuclear second. But normal time seems to us immune from such huge changes. It isn’t, though. In the last three decades, for example, the amount of carbon dioxide in the atmosphere has increased more than ten per cent, from about three hundred and fifteen parts per million to about three hundred and fifty parts per million. In the last decade, an immense “hole” in the ozone layer has opened up above the South Pole each fall, and, according to the Worldwatch Institute, the percentage of West German forests damaged by acid rain has risen from less than ten per cent to more than fifty per cent. Last year, for perhaps the first time since that starved Pilgrim winter at Plymouth, America consumed more grain than it grew. Burroughs again: “One summer day, while I was walking along the country road on the farm where I was born, a section of the stone wall opposite me, and not more than three or four yards distant, suddenly fell down. Amid the general stillness and immobility about me, the effect was quite startling. . . . It was the sudden summing-up of half a century or more of atomic changes in the material of the wall. A grain or two of sand yielded to the pressure of long years, and gravity did the rest.”
In much the same comforting way that we think of time as imponderably long, we consider the earth to be inconceivably large. Although with the advent of space flight it became fashionable to picture the planet as a small orb of life and light in a dark, cold void, that image never really took hold. To anyone of us, the earth is enormous, “infinite to our senses.” Or, at least, it is if we think about it in the usual horizontal dimensions. There is a huge distance between my house, in the Adirondack Mountains, and Manhattan—it’s a five-hour drive through one state in one country of one continent. But from my house to Allen Hill, near town, is a trip of five and a half miles. By bicycle it takes about twenty minutes, by car seven or eight. I’ve walked it in an hour and a half. If you turned that trip on its end, the twenty-minute pedal past Bateman’s sandpit and the graveyard and the waterfall would take me to the height of Mt. Everest—almost precisely to the point where the air is too thin to breathe without artificial assistance. Into that tight space, and the layer of ozone above it, are crammed all that is life and all that maintains life.
This, I realize, is a far from novel observation. I repeat it only to make the case I made with regard to time. The world is not as large as we intuitively believe—space can be as short as time. For instance, the average American car driven the average American stance—ten thousand miles—in an average American year releases its own weight in carbon into the atmosphere. Imagine every car on a busy freeway pumping a ton of carbon into the atmosphere, and the sky seems less infinitely blue.
Along with our optimistic perceptions of time and space, other, relatively minor misunderstandings distort our sense of the world. Consider the American failure to convert to the metric system. Like all schoolchildren of my vintage, I spent many days listening to teachers explain litres and metres and hectares and all the other logical units of measurement, and then promptly forgot about it. All of us did, except the scientists, who always use such units. As a result, if I read that there will be a rise of 0.8 degrees Celsius in the temperature between now and the year 2000, it sounds less ominous than a rise of a degree and a half Fahrenheit. Similarly, a ninety-centimetre rise in sea level sounds less ominous than a one-yard rise—and neither of them sounds all that ominous until one stops to think that over a beach with a normal slope such a rise would bring the ocean ninety metres (that’s two hundred and ninety-five feet) above its current tideline. In somewhat the same way, the logarithmic scale we use to determine the acidity or alkalinity of our soils and our waters—pH—distorts reality for anyone who doesn’t use it on a daily basis. Normal rainwater has a pH of 5.6. But the acidified rain that falls on Buck Hill, behind my house, has a pH of 4.6 to 4.2, which is from ten to fourteen times as acid as normal.
Of all such quirks, though, probably the most significant is an accident of the calendar: we live too close to the year 2000. Forever we have read about the year 2000. It has become a symbol of the bright and distant future, when we will ride in air cars and talk on video phones. The year 2010 still sounds far off, almost unreachably far off, as if it were on the other side of a great body of water. But 2010 is as close as 1970—as close as the breakup of the Beatles—and the turn of the century is no farther in front of us than Ronald Reagan’s election to the Presidency is behind. We live in the shadow of a number, and that makes it hard to see the future.
Our comforting sense, then, of the permanence of our natural world—our confidence that it will change gradually and imperceptibly, if at all—is the result of a subtly warped perspective. Changes in our world which can affect us can happen in our lifetime—not just changes like wars but bigger and more sweeping events. Without recognizing it, we have already stepped over the threshold of such a change. I believe that we are at the end of nature.
By this I do not mean the end of the world. The rain will still fall, and the sun will still shine. When I say “nature,” I mean a certain set of human ideas about the world and our place in it. But the death of these ideas begins with concrete changes in the reality around us, changes that scientists can measure. More and more frequently, these changes will clash with our perceptions, until our sense of nature as eternal and separate is finally washed away and we see all too clearly what we have done.
Svante Arrhenius took his doctorate at the University of Uppsala in 1884. His thesis earned him the lowest possible grade short of outright failure. Nineteen years later, the same thesis, which was on the conductivity of solutions, earned him a Nobel Prize. He later explained the initial poor reception: “I came to my professor, Cleve, whom I admired very much, and I said, ‘I have a new theory of electrical conductivity as a cause of chemical reactions.’ He said, ‘This is very interesting,’ and then he said, ‘Goodbye.’ He explained to me later that he knew very well that there are so many different theories formed, and that they are almost all certain to be wrong, for after a short time they disappeared; and therefore, by using the statistical manner of forming his ideas, he concluded that my theory also would not exist long.”
Arrhenius’s understanding of electrolytic conduction was not his only shrug-provoking new idea. As he surveyed the first few decades of the Industrial Revolution, he realized that man was burning coal at an unprecedented rate—“evaporating our coal mines into the air.” Scientists already knew that carbon dioxide, a by-product of fossil-fuel combustion, trapped solar infrared radiation that would otherwise have been reflected back to space. The French polymath Jean-Baptiste-Joseph Fourier had speculated about the effect nearly a century before, and had even used the hothouse metaphor. But it was Arrhenius, employing measurements of infrared radiation from the full moon, who did the first calculations of the possible effects of man’s stepped-up production of carbon dioxide. The average global temperature, he concluded, would rise as much as nine degrees Fahrenheit if the amount of carbon dioxide in the air doubled from its pre-industrial level; that is, heat waves in mid-American latitudes would run as high as a hundred and thirty degrees, the seas would rise several metres, crops would wither in the fields.
This idea floated in obscurity for a very long time. Now and then, a scientist took it up—the British physicist G. S. Callendar speculated in the nineteen-thirties that rising carbon-dioxide levels could account for the warming of North America and northern Europe which meteorologists had begun to observe in the eighteen-eighties. But that warming seemed to be replaced by a decline, beginning in the nineteen-forties; in any case, we were too busy creating better living through petroleum to be bothered with such long term speculation. And the few scientists who did consider the matter concluded that the oceans, which hold much more carbon dioxide than the atmosphere, would soak up any excess that man churned out—that the oceans were an infinite sink down which to pour the problem.
Then, in 1957, two scientists at the Scripps Institution of Oceanography, in California, Roger Revelle and Hans Suess, published a paper in the journal Tellus on this question of the oceans. What they found may turn out to be the single most important limit in an age of limits. They found that the conventional wisdom was wrong: the upper layer of the oceans, where the air and sea meet and transact their business, would absorb less than half of the excess carbon dioxide produced by man. “A rather small change in the amount of free carbon dioxide dissolved in seawater corresponds to a relatively large change in the pressure of carbon dioxide at which the oceans and atmosphere are at equilibrium,” they wrote. That is to say, most of the carbon dioxide being pumped into the air by millions of smokestacks, furnaces, and car exhausts would stay in the air, where, presumably, it would gradually warm the planet. “Human beings are now carrying out a large-scale geophysical experiment of a kind that could not have happened in the past nor be repeated in the future,” they concluded, adding, with the morbid dispassion of true scientists, that this experiment, “if adequately documented, may yield a far-reaching insight into the processes of weather and climate.” While there are other parts to this story—the depletion of the ozone, acid rain, genetic engineering—the story of the end of nature centers on this greenhouse experiment, with what will happen to the weather.
When we drill into an oil field, we tap into a vast reservoir of organic matter—the fossilized remains of aquatic algae. We unbury it. When we burn oil—or coal, or methane (natural gas)—we release its carbon into the atmosphere in the form of carbon dioxide. This is not pollution in the conventional sense. Carbon monoxide is pollution—an unnecessary by-product; a clean-burning engine releases less of it. But when it comes to carbon dioxide a clean-burning engine is no better than the motor in a Model T. It will emit about five and a half pounds of carbon in the form of carbon dioxide for every gallon of gasoline it consumes. In the course of about a hundred years, our various engines and industries have released a very large portion of the carbon buried over the last five hundred million years. It is as if someone had scrimped and saved his entire life and then spent everything on one fantastic week’s debauch. In this, if in nothing else, wrote the great biologist A. J. Lotka, “the present is an eminently atypical epoch.” We are living on our capital, as we began to realize during the oil crises of the nineteen-seventies. But it is more than waste, more than a binge. We are spending that capital in such a way as to alter the atmosphere.
There has always been, at least since the start of life, a certain amount of carbon dioxide in the atmosphere, and it has always trapped a certain amount of the sun’s radiation to warm the earth. If there were no atmospheric carbon dioxide, our world might resemble Mars: it would probably be so cold as to be lifeless. A little greenhouse effect is a good thing—life thrives in its warmth. The question is: How much? On Venus, the atmosphere is ninety-seven per cent carbon dioxide. As a result, it traps infrared radiation a hundred times as efficiently as the earth’s atmosphere, and keeps the planet toasty seven hundred degrees warmer than the earth. The earth’s atmosphere is mostly nitrogen and oxygen; it is only about .035 per cent carbon dioxide, which is hardly more than a trace. The worries about the greenhouse effect are worries about raising that figure to .055 or .06 per cent, which is not very much. But enough, it turns out, to make everything different.
In 1957, when Revelle and Suess wrote their paper, no one even knew for certain whether carbon dioxide was increasing. The Scripps Institution hired a young researcher, Charles Keeling, and he set up monitoring stations at the South Pole and on the side of Mauna Loa, in Hawaii, eleven thousand feet above the Pacific. His data soon confirmed their hypothesis: more and more carbon dioxide was entering the atmosphere. When the first readings were taken, in 1958, the atmosphere at Mauna Loa contained about three hundred and fifteen parts per million of carbon dioxide. Subsequent readings showed that each year the amount increased, and at a steadily growing rate. Initially, the annual increase was about seven-tenths of a part per million; in recent years, the rate has doubled, to one and a half parts per million. Admittedly, one and a half parts per million sounds absurdly small. But scientists, by drilling holes in glaciers and testing the air trapped in ancient ice, have calculated that the carbon-dioxide level in the atmosphere prior to the Industrial Revolution was about two hundred and eighty parts per million, and that this was as high a level as had been recorded in the past hundred and forty thousand years. At a rate of one and a half parts per million per year, the pre-Industrial Revolution concentration of carbon dioxide would double in the next hundred and forty years. Since, as we have seen, carbon dioxide at a very low level largely determines the climate, carbon dioxide at double that very low level, small as it is in absolute terms, could have an enormous effect.
And the annual increase seems nearly certain to go higher. The essential facts are demographic and economic, not chemical. The world’s population has more than tripled in this century, and is expected to double, and perhaps triple again, before reaching a plateau in the next century. Moreover, the tripled population has not contented itself with using only three times the resources. In the last hundred years, industrial production has grown fiftyfold. Four-fifths of that growth has come since 1950, almost all of it based on fossil fuels. In the next half century, a United Nations commission predicts, the planet’s thirteen-trillion-dollar economy will grow five to ten times larger.
These facts are almost as stubborn as the chemistry of infrared absorption. They mean that the world will use more energy—two to three per cent more a year, by most estimates. And the largest increases may come in the use of coal—which is bad news, since coal spews more carbon dioxide into the atmosphere than any other fuel. China, which has the world’s largest hard coal reserves and recently passed the Soviet Union as the world’s largest coal producer, has plans to almost double coal consumption by the year 2000. A model devised by the World Resources Institute predicts that if energy use and other contributions to carbon-dioxide levels continue to grow very quickly, the amount of atmospheric carbon dioxide will have doubled from its pre-Industrial Revolution level by about 2040; if they grow somewhat more slowly, as most estimates have it, the amount will double by about 2070. And, unfortunately, the solutions are neither obvious nor easy. Installing some kind of scrubber on a power-plant smokestack to get rid of the carbon dioxide might seem an obvious fix, except that a system that removed ninety per cent of the carbon dioxide would reduce the effective capacity of the plant by eighty per cent. One often heard suggestion is to use more nuclear power. But, because so much of our energy is consumed by automobiles and the like, even if we mustered the political will and the economic resources to quickly replace each of our non-nuclear electric plants with nuclear ones our carbon-dioxide output would fall by only about thirty per cent. The same argument would apply, at least initially, to fusion or any other clean method of producing electricity.
Burning fossil fuels is not the only method human beings have devised to increase the level of atmospheric carbon dioxide. Burning down a forest also sends clouds of carbon dioxide into the air. Trees and shrubby forests still cover forty per cent of the land on earth, but the forests have shrunk by about a fifth since pre-agricultural times, and the shrinkage is accelerating. In the Brazilian state of Pará, for instance, nearly seventy thousand square miles were deforested between 1975 and 1986; in the hundred years preceding that decade, settlers had cleared about seven thousand square miles. The Brazilian government has tried to slow the burning, but it employs fewer than nine hundred forest wardens in an area larger than Europe.
This is not news; it is well known that the rain forests are disappearing, and are taking with them a majority of the world’s plant and animal species. But forget for a moment that we are losing a unique resource, a cradle of life, irreplaceable grandeur, and so forth. The dense, layered rain forest contains from three to five times as much carbon per acre as an open, dry forest—an acre of Brazil in flames equals between three and five acres of Yellowstone. Deforestation currently adds about a billion tons of carbon to the atmosphere annually, which is twenty per cent or more of the amount produced by the burning of fossil fuels. And that acre of rainforest, which has poor soil and can support crops for only a few years, soon turns to desert or to pastureland. And where there’s pasture there are cows. Cows support in their stomachs huge numbers of anaerobic bacteria, which break down the cellulose that cows chew. That is why cows, unlike people, can eat grass. The bugs that digest the cellulose excrete methane, the same natural gas we use as fuel. And unburned methane, like carbon dioxide, traps infrared radiation and warms the earth. In fact, methane is twenty times as efficient as carbon dioxide at warming the planet, so even though it makes up less than two parts per million of the atmosphere it can have a significant effect. Though it may come from seemingly “natural” sources—the methanogenic bacteria—the present huge numbers of these bacteria are man’s doing. Mankind owns well over a billion head of cattle, not to mention a large number of camels, horses, pigs, sheep, and goats; together, they belch about seventy-three million metric tons of methane into the air each year—a four-hundred-and-thirty-five-per-cent increase in the last century.
We have raised the number of termites, too. Like cows, termites harbor methanogenic bacteria, which is why they can digest wood. We tend to think of termites as house-wreckers, but in most of the world they are housebuilders, erecting elaborate, rock-hard mounds twenty or thirty feet high. If a bulldozer razes a mound, worker termites can rebuild it in hours. Like most animals, they seem limited only by the supply of food. When we clear a rainforest, all of a sudden there is dead wood everywhere—food galore. As deforestation has proceeded, termite numbers have boomed; Patrick Zimmerman, of the National Center for Atmospheric Research, in Boulder, Colorado, estimates that there is more than half a ton of termites for every man, woman, and child on earth. Termites excrete phenomenal amounts of methane: a single mound may give off five litres a minute.
Researchers differ on the importance of termites as a methane source, but they agree about rice paddies. The oxygenless mud of marsh bottoms has always sheltered the methane-producing bacteria. (Methane is sometimes known as swamp gas.) But rice paddies may be even more efficient; the rice plants themselves act a little like straws, venting as much as a hundred and fifteen million tons of methane annually. And rice paddies must increase in number and size every year, to feed the world’s growing population. Then, there are landfills. Twenty per cent of a typical landfill is putrescible: it rots, creating carbon dioxide and methane. At the main New York City landfill, on Staten Island, the methane is pumped from under the trash straight to the stoves of thousands of homes, but at most landfills it just seeps out.
What’s more, some scientists have begun to think that these sources by themselves may not account for all the methane. For one thing, an enormous amount of methane is locked up as hydrates in the tundra and in the mud of the continental shelves. These are, in essence, methane ices; the ocean muds alone may hold ten trillion tons of methane. If the greenhouse effect warms the oceans, if it begins to thaw the permafrost, then those ices could start to melt. Some estimates of the potential methane release from the ocean muds run as high as six hundred million tons a year—an amount that would more than double the present atmospheric concentration. This would be a nasty example of a feedback loop: warm the atmosphere and release methane; release methane and warm the atmosphere; and so on.
When all the sources of methane are combined, we have done an even more dramatic job of increasing methane than of increasing carbon dioxide. Samples of ice from Antarctic glaciers show that the concentration of methane in the atmosphere has fluctuated between 0.3 and 0.7 parts per million for the last hundred and sixty thousand years, reaching its highest levels during the earth’s warmest periods. In 1987, methane composed 1.7 parts per million of the atmosphere; that is, there is now two and a half times as much methane in the atmosphere as there was at any time since the onset of the ice age preceding the most recent one. The level is now increasing at a rate of one per cent a year.
Man is also pumping smaller quantities of other greenhouse gases into the atmosphere. Nitrous oxide, the chlorofluorocarbons—which are notorious for their ability to destroy the planet’s ozone layer—and several more all trap warmth with greater efficiency than carbon dioxide. Methane and the rest of these gases, even though their concentrations are small, will together account for fifty per cent of the projected greenhouse warming. They are as much of a problem as carbon dioxide. And as all these compounds warm the atmosphere it will be able to hold more water vapor—itself a potent greenhouse gas. The British Meteorological Office calculates that this extra water vapor will warm the earth two-thirds as much as the carbon dioxide alone.
Most discussion of the greenhouse gases rushes immediately to their future consequences, without pausing to let the simple fact of what has already happened sink in: the air around us—even where it’s clean, and smells like spring, and is filled with birds—is significantly changed. We have substantially altered the earth’s atmosphere.
That said, the question of what this new atmosphere means must arise. The direct effects are unnoticeable. Anyone who lives indoors breathes carbon dioxide at a level several times the atmospheric concentration without suffering any harm; the federal government limits industrial workers to a chronic exposure of five thousand parts per million, or almost fifteen times the current atmospheric level. A hundred years from now, a child at recess will still breathe far less carbon dioxide than a child in a classroom. This, however, is only mildly good news. Changes in the atmosphere will change per the weather and that will change recess. The weather—the temperature, the amount of rainfall, the speed of the wind—will change. The chemistry of the atmosphere may seem an abstraction, a text written in a foreign language. But its translation into the weather of New York and Cincinnati and San Francisco will change the life of each of us.
Theories about the effects all begin with an estimate of expected warming. The wave of concern that began with Revelle and Suess’s article and Keeling’s Mauna Loa and South Pole data has led to the development of complex computer models of the entire globe. The models agree that when, as has been predicted, carbon dioxide (or the equivalent combination of carbon dioxide and other greenhouse gases) doubles from the pre-Industrial Revolution level, the average global temperature will increase, and that the increase will be one and a half to five and a half degrees Celsius, or three to ten degrees Fahrenheit. Perhaps the most famous of these computer models has been constructed by James Hansen and his colleagues at the National Aeronautics and Space Administration’s Goddard Institute for Space Studies. Even though it remains a rough simulation of the real world, they have improved it to the point where they are willing to forecast not just the effects of a doubling of carbon dioxide but the incremental effects along the way—that is, not just the forecast for 2050 but the one for 2000.
Take Dallas, for instance. According to Hansen’s calculations, the doubled level of gases would increase the annual number of days with temperatures above 100℉. from nineteen to seventy-eight. On sixty-eight days, as opposed to the current four, the nighttime temperature wouldn’t fall below 80℉. A hundred and sixty-two days a year—half the year, essentially—the temperature would top 90℉. New York City would have forty-eight days a year above the ninety-degree mark, up from fifteen at present. And so on. This would clearly change the world as we know it. One of Hansen’s colleagues told reporters, “It reaches a hundred and twenty degrees in Phoenix now. Will people still live there if it’s a hundred and thirty degrees? A hundred and forty?” (And such heat waves are possible even if the average global increase, figured over a year, is only a couple of degrees, since any average conceals huge swings.) These changes, Hansen and his colleagues said in a paper published last fall in the Journal of Geophysical Research, should begin to be obvious to the man in the street by the early nineteen-nineties; that is, the odds of a very hot summer will, thanks to the greenhouse effect, become better than even beginning now.
In recent years, there have, of course, been any number of doomladen prophecies that haven’t come true—oil is selling at eighteen dollars a barrel, half its price just a few years ago. Is the warming theory valid? The obvious way to check is to measure the temperature and see if it’s going up. But this is easier said than done. In the first place, the warming doesn’t show up immediately. The oceans can hold a lot of heat; the warming so far may be stored there, ready to re-radiate out to the atmosphere, the way the sun’s heat is held through the night by a rock. This “thermal lag” may be as little as ten years, as much as a hundred. And when you check the thermometers it won’t do to measure only a few places for only a few years, because climate is “noisy”—full of random fluctuations. (If you had spent this summer in Tucson, for example, you would have been sure that something was happening: the city set forty-seven high-temperature records. New York, by contrast, has had fairly normal summer temperatures.) To find what climatologists call the “warming signal” through the static of naturally cold and hot years requires an enormous effort. Two such studies have been done—one by Hansen and his NASA colleagues, the other at the University of East Anglia. The studies reach back to 1880, when scientists first began systematic weather observations. To find truly global averages, they include readings from thousands of land-based and shipboard monitoring stations. Both studies conclude that the earth’s temperature increased a little more than a degree Fahrenheit from 1880 to 1980. This is consistent with what most of the greenhouse models indicate. Updates of both studies show that the four warmest years on record occurred in the nineteen-eighties; the rise is accelerating as more gases enter the air, just as the models indicate. The British study lists the six warmest years on record as (in descending order) 1988, 1987, 1983, 1981, 1980, and 1986.
In 1988, the American drought hit the heart of the Grain Belt, where most of the nation’s and much of the world’s food is grown. It followed a dry fall and winter, so its effects were quickly evident; the Mississippi River, for example, sank to its lowest level since 1872, when the Navy began taking measurements. And just about the time that the pictures on television began to grab everyone’s attention it got very, very hot in the urban East, where those in the government and the media establishment, among others, have their homes. It happened that in late June, as the anxiety intensified—newscasters telling us that the next two weeks were crucial for corn pollination, meteorologists issuing pessimistic sixty-day forecasts—the Senate Committee on Energy and Natural Resources held a hearing on the greenhouse effect. It was actually the second part of the hearing. Part I had been held the previous November, when, according to the Louisiana Democrat J. Bennett Johnston, the senators listened with “concern” as they were told that one expected result of the greenhouse effect would be a drying of the Midwest and the Southeast. But now, “as we experience a-hundred-and-one-degree temperatures in Washington, D.C., and [reduced] soil moisture across the Midwest is ruining the soybean crops, the corn crops, the cotton crops,” Senator Johnston said, concern was giving way to “alarm.” Several of the senators said that they had already read the report of Dr. Hansen, the chief witness, and predicted that it would startle listeners. Hansen’s report, Dale Bumpers, of Arkansas, said, should be “cause for headlines in every newspaper in America tomorrow morning.” As it turned out, he was not exaggerating. Hansen testified that he was ready to state that the warming signal was beginning to emerge above the noise of normal weather, that there was only a one per cent chance that the temperature increases seen in the last few years were accidental, and that we now lived in the greenhouse world.
It was a claim no other established scientist had made—certainly not one on a government payroll. The reaction was much as the senators had expected. The next day’s Times, for instance, ran a story at the top of the front page under the headline “GLOBAL WARMING HAS BEGUN, EXPERT TELLS SENATE.” The message was finally getting across, nearly a century after Arrhenius and three decades after Revelle and Suess. But the heat of the day may have been a mixed blessing; though it focussed everyone’s attention on the issue, it also led most people to think that what Hansen had said was that the heat and drought of 1988 were greenhouse-related. Strictly speaking, that is not what he had testified to. “It is not possible to blame a specific heat wave or drought on the greenhouse effect,” he said—and, indeed, some experts think that the drought and heat of 1988 were mainly the result of a fluctuation of tropical ocean currents which steered the North American jet stream, with its cargo of rainstorms, north of the Great Plains.
What we can blame the carbon dioxide and the methane for is a longer range pattern. Even if the summer of 1988 had been cool and damp, even if there had been mushrooms growing in the wheat fields of Kansas, Hansen would have said the same thing. What had convinced him was not the devastation in the Midwest or the misery in the Eastern cities but the numbers that his computer kept spitting at him. “There are two time scales to consider,” he explained, some months after giving his testimony. “One is the last three complete decades, for which the natural variability in temperature has been calculated—it is about point thirteen degrees Celsius. This coincides roughly with the thirty years for which we have precise measurements of carbon dioxide and other gases. And our readings show that the global mean temperature has risen about point four degrees in the three-decade period. The other is the larger record—the observations back to the eighteen-eighties. Over that period, there’s been about a point-six-degree-Celsius rise. Now, over a longer period there’s also more natural variability—sources like fluctuations in solar activity, deep ocean circulation, and so forth.” The standard deviation over the longer period, he noted, was about .2°C. So in both cases Hansen’s observed rise was almost exactly three times the standard deviation. “There’s no magic point where you pick out the signal,” he said. “But when it gets to three sigma—when it gets to three times the standard deviation—you’re getting to a level where it’s unlikely to be an accidental warming.”
Some recent studies tend to agree with Hansen’s conclusion that the warming has already begun: precipitation appears to have increased above 35 degrees north latitude and decreased below it since the early nineteen-fifties, for instance—a result anticipated in the greenhouse models. And some investigators have found a “variable but widespread” warming of the Alaskan permafrost, which changes temperature much more slowly than the air and thus may provide a better record.
But not all scientists—not even all those committed to the greenhouse theory—believe that the warming has already begun. Hansen, though well respected, is out on a limb, if a fairly stout one. Some have taken issue with his use of statistics, and others with his outspokenness. At a workshop on global warming at Amherst College this spring, the assembled climatologists concluded that while it was “tempting to attribute” the recent warm years to the greenhouse effect “such an attribution cannot now be made with any degree of confidence.” Stephen Schneider, a senior scientist at the National Center for Atmospheric Research and a longtime proponent of the greenhouse theory, offers a gambler’s analogy: the warm years of the nineteen-eighties, he says, are not “proof” of a warming any more than a dealer’s drawing four aces “proves” that he’s dealing from the bottom of the deck. “Different tastes cause some people to accept the reality of a hypothesized climatic change at a low signal-to-noise ratio, whereas others might not believe in the reality of the change until a large signal has persisted for a very long time,” Schneider told the Senate two months after Hansen testified. “Quite simply, accepting any particular signal-to-noise ratio as ‘proof’ of global warming reflects the personal judgment of the investigator.”
Kenneth Watt, a professor of zoology and environmental studies at the University of California at Davis, says that studies such as Hansen’s fail to correct enough for the “urban-heat-island effect”—a phenomenon well known to meteorologists, in which, as cities grow up around thermometers, concrete and exhaust skew readings. There’s also no guarantee that other factors—solar flares, perhaps, which coincide with both warming and cooling trends, or the strong El Niño current of recent years—aren’t skewing the readings. Last January, Tim Barnett, a climatologist at Scripps, correctly forecast much cooler low-latitude temperatures for the first part of this year as a result of “La Niña,” a tropical “cold event” that is the opposite of El Niño. During the summer of 1988, in some parts of the ocean off equatorial South America the water temperature dropped 7°F. Hansen saw the dip in his computer data, and he agrees that it may make this year’s over-all readings go down. “But such things are bumps,” he says.
But few of the objections are to the theory as a whole. Everyone in the scientific community agrees that carbon dioxide is on the rise, and almost everyone believes that the rise cannot help having some effect. An occasional scientist says that the onset of the effect may be delayed as much as forty years, but this is considerably different from dismissing it. Last May, Hansen returned to Capitol Hill to tell the Senate’s Science, Technology, and Space Subcommittee that his studies showed a definite danger of future drought. The White House tried to alter his testimony, arguing that, in the words of the Presidential press secretary, Marlin Fitzwater, “there are many points of view on the global warming issue.” But Fitzwater didn’t cite any studies undercutting Hansen’s, and the same day Stephen Schneider assured the subcommittee that “there is virtually no scientific controversy” over the contention that more carbon dioxide in the atmosphere will produce higher temperatures. “That’s not a speculative theory,” he said.
There is debate, though, over the question of what will happen as the heating begins. A large-scale change in the climate will set off a series of other changes, and while some of these would make the problem worse, others might lessen it. Skeptics are inclined to argue that the warming will trigger some natural compensatory brake. S. Fred Singer, a professor of environmental sciences at the University of Virginia, has assumed a part-time role as greenhouse curmudgeon, expressing his doubts to reporters and on various Op-Ed pages. He grants that the earth’s temperature should increase “provided that all other factors remain the same.” But, he says, they won’t. “For example, as oceans warm and more water vapor enters the atmosphere, the greenhouse effect will increase somewhat, but so should cloudiness—which can keep out incoming solar radiation and thereby reduce the warming.” There are other possibilities. “The feedbacks are enormously complicated,” Michael MacCracken, of the Lawrence Livermore National Laboratory, in California, told Time in 1987. “It’s like a Rube Goldberg machine in the sense of the number of things that interact in order to tip the world into fire or ice.”
The computer models have tried to incorporate such factors. In some cases, Hansen admits, we simply don’t have enough knowledge to make more than educated guesses; the behavior of the oceans is something of a wild card, and so are the clouds. (The difficulty of estimating cloud feedback is a major reason that most warming predictions are expressed as a range of temperatures, and not as a single number.) But almost every doubt is double-edged. Low-level stratocumulus clouds reflect a lot of solar radiation and might tend to cool the earth. Monsoon clouds, on the other hand, are long and thin, and let in the sun’s heat while preventing its escape. Hansen’s work suggests that the over-all effect of clouds will be to increase the warming.
A variety of other feedback effects have also been identified and tallied up. For instance, every surface has an albedo—a degree to which it reflects light. A polar ice cap, or a white shirt, has a high albedo—a large proportion of the sun’s rays are reflected back into space. If the ice is replaced by dark-blue ocean, more heat will be absorbed. Tropical rain forests absorb a lot of heat now; if they turn to deserts, these deserts will reflect heat. The feedbacks are products of the warming signal, and are distinct from phenomena that always have affected and always will affect temperature—volcanoes, say, which can throw up so much dust that it acts as a veil, or El Niños, or solar flares. In any event, the warming estimates provided by the computer models are not worst-case scenarios. They are the middle ground. Stephen Schneider told the Senate energy committee last year that it was “equally likely” that the warming forecasts were too low as that they were too high.
Some of the potential feedbacks are so enormous that they may someday make us almost forget what originally caused the greenhouse warming. Twenty thousand years ago, the land that surrounds my house in the Adirondacks was covered by glaciers that had spread slowly down from Canada, and eventually retreated there. As the ice disappeared, “the fierce ruthlessness of nature gave way to a benevolent mood,” in the words of a local writer. “Rains came over the years to chasten the harshness of the landscape. The startling gaping holes in the earth were filled with crystal-clear water. Soft green foliage came to clothe the naked rock-hewn slopes.” This was a slow process, and is even now incomplete—some plant and animal species are still migrating up here. Great forests rose on the glacial till and soon created more soil for greater forests, and so on—a process that was first interrupted a couple of hundred years ago, when men began cutting down most of the Adirondack woods. But this interruption was only temporary; just before the turn of this century, New York State, in an early burst of environmental consciousness, began buying huge tracts of land in the Adirondacks and stipulating that they be “forever kept as wild”—off limits to loggers and real-estate developers alike. As a result, this area, though still threatened, is a happy exception—a reforested, replenished zone, a second-chance wilderness.
But the trees that live here don’t do so because of the laws; they do so because of the climate. They have slowly marched north as the climate warmed since the end of the last ice age, and if it continued slowly warming they would slowly keep marching; the convoy of pines might march right out of here, and the mass of hardwoods found in lower Appalachian latitudes might march in to replace them. But before we get too used to this marching metaphor it is worth recalling that trees are rooted in the ground; forests move only by the slow growth of new trees along their edges. In a year, a forest moves, naturally, a half mile at most. Which is fine, if that’s how slowly the climate is changing. The computer models, however, project an increase in average global temperature as high as one degree Fahrenheit per decade. An increase of one degree in average global temperature moves the climatic zone some thirty-five to fifty miles north. So if the temperature increases one degree per decade the forest surrounding my home would be due at the Canadian border by 2020, which is just about the time that we’d be expecting the trees from a hundred miles south to start arriving. They won’t—half a mile a year is as fast as forests move. The trees outside my window will still be there, but they’ll be dead or dying.
Eventually, perhaps within a few decades, forests—or, at least, scrub better adapted to the new conditions—will replace the forests that expired. But in the meantime those dead forests will release tremendous amounts of carbon to the atmosphere. Last year’s Yellowstone fires released carbon amounting to 2.8 per cent of this country’s annual emissions from fossil fuels; that is, in a dozen weeks, on only about a million and a half acres, the fires released as much carbon as ten days’ worth of driving, home heating, factory production, motorboating, and so on. The world’s forests, plants, and soil (which gives up its carbon much more rapidly as trees die) contain more than two trillion tons of carbon, probably more than a third of it in the middle and high latitudes. By contrast, the atmosphere at present contains only about seven hundred and fifty billion tons. So even a fairly small change in the forests could substantially increase the amount of carbon dioxide in the atmosphere, intensifying the warming.
This vast decline, this forest “dieback,” is not some distant proposition. A 1988 study issued by the World Meteorological Organization and the United Nations Environmental Program found that, given a fairly rapid warming, “reproductive failure and forest dieback is estimated to begin between 2000 and 2050.” A University of Virginia study predicts what Michael Oppenheimer, of the Environmental Defense Fund, calls “biomass crashes” in the pine forests of the southeastern United States over the next forty years if the warming continues. Last September, James Hansen told reporters that the birch trees and many of the evergreens of the Northeast “may have a hard time surviving, even in the next ten to twenty years.” There are signs—frightening signs—that some of the feedback loops are starting to kick in. In May, George Woodwell, a biologist at the Woods Hole Research Center, told the Senate’s science-and-technology subcommittee that the annual one-and-a-half-parts-per-million increase in atmospheric carbon dioxide seemed to have surged upward in the last eighteen months to two and a half parts per million. “I’m suggesting that the warming of the earth is increasing the decay of organic matter,” he said, adding that such an event had not been worked into the computer climate models—in other words, their estimates of future warming might well be too low.
For the moment, though, forget about the higher temperatures and the dead trees and the other effects. The physical consequences of increasing the level of carbon dioxide will be staggering, but no more staggering than the simple fact of what we have already done. Carbon-dioxide levels have gone up significantly, and globally. Elevated levels can be measured far from industry and miles above the ground. And the changes are irrevocable. They are not possibilities. They cannot be wished away, and they cannot be legislated away. To prevent them, we would have had to clean up our collective act many decades ago. We have done this ourselves—by driving our cars, running our factories, clearing our forests, growing our rice, turning on our air-conditioners. In the years since the Civil War, and especially in the years since the Second World War, we have changed the atmosphere—changed it enough so that the climate will change dramatically. Most of the major events of human history gradually lose their meaning: wars that seemed at the time all-important are now a series of dates that schoolchildren don’t even try to remember; great feats of engineering crumble in the desert. But now the way of life of one part of the world in one half century is altering every inch and every hour of the planet.
Most mornings, I hike up the hill outside my back door. Within a hundred yards, the woods swallow me up, and there is nothing to remind me of human society—no trash, no stumps, no fences, not even a real path. Looking out from the high places, you can’t see road or house; it is a world apart from man. But once in a while someone will be cutting wood farther down the valley, and the snarl of a chain saw will fill the woods. It is harder these days to get caught up in the timelessness of the forest, for man is nearby. The sound of the chainsaw doesn’t blot out all the noises of the forest, or drive the animals away, but it does drive away the feeling that you are in another, separate, wild sphere.
Now that we have changed the most basic forces around us, the noise of that chain saw will always be in the woods. We have changed the atmosphere, and that is changing the weather. The temperature and the rainfall are no longer entirely the work of some uncivilizable force but instead are in part a product of our habits, our economies, our ways of life. Even in the most remote wilderness, where the strictest laws forbid the felling of a single tree, the sound of that saw will be clear, and a walk in the woods will be changed by its whine. The world outdoors will mean the same thing as the world indoors, the hill the same thing as the house. An idea can become extinct, just like an animal or a plant. The idea in this case is “nature”—the wild province, the world apart from man, under whose rules he was born and died. We have not ended rainfall or sunlight. The wind still blows—but not from some other sphere, some inhuman place. It is too early to tell exactly how much harder the wind will blow, how much hotter the sun will shine. That is for the future. But their meaning has already changed.
The argument that nature is ended is complex; profound objections to it are possible, and I will try to answer them. But to understand what is ending requires some attention to the past. Not the ancient past, not the big bang or the primal soup—the European exploration of the New World is far enough back, since it is man’s idea of nature that is important to this discussion, and it was in response to that wild country that much of our modern notion of nature developed. North America was not unaltered by man when the Europeans arrived, but its previous occupants had treated it fairly well. Most of it was still wilderness on the eve of the Revolution, when William Bartram, one of America’s first professional naturalists, set out from his native Philadelphia to tour the South. Though some of the land through which he travelled had been settled (he spent a number of nights on plantations), the settlement was sparse, and the fields of indigo and rice gave way quickly to wilderness—not the dark and forbidding wilderness of European fairy tales but a blooming, humming, fertile paradise. Every page of his diary of the journey through “North & South Carolina, Georgia, East & West Florida, the Cherokee Country, the Extensive Territories of the M uscogulges, or Creek Confederacy, and the Country of the Chactaws” shouts of the fecundity, the profligacy, of that fresh land: “I continued several miles [over] verdant swelling knolls, profusely productive of flowers and fragrant strawberries, their rich juice dyeing my horse’s feet and ankles.” When he stops for dinner, he picks a wild orange, and stews a fresh-caught trout in its juice over his fire.
Whatever direction he struck off in, Bartram found vigorous beauty. His diary brims over with the grand Latin binomials of a thousand plants and animals (Kalmia latifolia, “snowy mantled” Philadelphus inodorus, Pinus sylvestris, Populus tremula, Rheum rhaponticum, Magnolia grandiflora) and also with the warm common names—the bank martin, the water wagtail, the mountain cock, the chattering plover, the bumblebee. But the roll call of his adjectives is even more indicative of his mood. In the account of a single evening, he musters fruitful, fragrant, sylvan (twice), moderately warm, exceeding pleasant, charming, fine, joyful, most beautiful, pale gold, golden, russet, silver (twice), ultramarine, velvet-black, orange, prodigious, gilded, delicious, harmonious, soothing, tuneful, sprightly, elevated, cheerful (twice), high and airy, brisk and cool, clear, sweet, and healthy. And where he can’t see, he imagines marvels: the fish disappearing into subterranean streams, “where, probably, they are separated from each other, by innumerable paths, or secret rocky avenues; and after encountering various obstacles, and beholding new and unthought-of scenes of pleasure and disgust, after many days absence from the surface of the world emerge again from the dreary vaults, and appear exulting in gladness, and sporting in the transparent waters of some far distant lake.” But he is no Disney—this is no “Fantasia.” He is a scientist recording his observations, and words like “cheerful” and “sweet” seem to be technical descriptions of the untouched world in which he wandered.
This sort of joy in the natural world was not a literary convention, a given. Much of literature regarded wilderness as ugly and crude until the Romantic movement of the late eighteenth century; Andrew Marvell, for one, referred to mountains as “ill-designed excrescences.” This silliness changed into a new silliness with the Romantics. Chateaubriand’s immensely popular “Atala” describes the American wilderness as full of bears “drunk with grapes, and reeling on the branches of the elm trees.” But the rapturous fever took on a healthier aspect in this country. Most of the pioneers, to be sure, saw a buffalo as something to hunt, a forest as something to cut down, a flock of passenger pigeons as a call for heavy artillery (farmers would bring their hogs to feed on the carcasses raining down in the slaughter), but there were always a good many—even, or especially, among the hunters and loggers—who recognized and described the beauty and order of this early time.
Of a thousand examples, my favorite single description comes from George Catlin, who travelled the frontier in the eighteen-thirties to paint the portraits of American Indians. In his journal he describes a valley, “far more beautiful than could have been imagined by mortal man,” in which he spent the night on a ride north from Fort Gibson to the Missouri River:
If this passage had a little number at the start of each sentence, it could be Genesis; it sticks in my mind as a baseline, a reminder of where we began.
Such visions of the world as it existed outside human history became scarcer with each year that passed. By 1929, when Bob Marshall, a co-founder of the Wilderness Society, set off to explore Alaska’s Brooks Range, every stretch of the lower forty-eight had been visited, mapped, and named. Each day of his trek brought eight, ten, a dozen ridges and streams and peaks under his eye, and hence into human history:
Marshall was very nearly the last person to see any part of this continent unpolluted even by the knowledge that someone had been there before. His explorations were a last echo of the journeys of discovery that had marked an earlier epoch. It is hard for us to believe that only a hundred and twenty years ago the valley of the Colorado River—the Grand Canyon—was a blank spot on maps of the Southwest, or that fifty years before that the Rockies were a rumor among white men. When Thoreau climbed Mt. Katahdin, in 1846, he could list the five white men who had preceded him to the peak. “I am reminded by my journey how exceedingly new this country still is,” Thoreau wrote. “Those Maine woods differ essentially from ours [in Concord]. There you are never reminded that the wilderness which you are threading is, after all, some villager’s familiar wood-lot, some widow’s thirds, from which her ancestors have sledded fuel for generations, minutely described in some old deed.” Nowadays, Katahdin, though preserved as a park, is so jammed with climbers that the authorities must limit their number; sometimes several hundred people are at the summit at once. On a holiday weekend, the trail up Mt. Marcy, the Adirondacks’ highest peak, is like Macy’s escalators with a heavy balsam scent.
Over time, though, we’ve reconciled ourselves to the idea that we’ll not be the first up any hill. The wonder of nature does not depend on its freshness. The Grand Canyon is so grand that we don’t mind not being the first people to see it. But still we feel the need for pristine places. We have legislated wilderness, set aside big tracts of land where, in the words of the federal statute, “the earth and its community of life are untrammelled by man.” Even if we don’t visit them, they matter to us. The Arctic National Wildlife Refuge, on Alaska’s northern shore, is reached by just a few hundred people a year, but it has a vivid life in the minds of many more, who are upset that oil companies want to drill there. They are upset not only because it might harm the caribou but because here is a vast space free of roads and buildings and antennas—a blank spot.
When Rachel Carson wrote “Silent Spring,” she was able to find some parts of the Arctic still untouched—no DDT in the fish, the beaver, the beluga, the caribou, the moose, the polar bear, the walrus. The cranberries, the salmonberries, and the wild rhubarb all tested clean, though two snowy owls, probably as a result of their migrations, carried small amounts of the pesticide, as did fat samples from several Eskimos who had been away to the hospital in Anchorage. In other words, as pervasive a problem as DDT was and is, one could always imagine that somewhere a place existed free of its taint. (And, largely as a result of Carson’s book, there are more and more such places.) As pervasive and growing as the problem of acid rain surely is, at the moment places still exist with a rainfall of an acceptable pH. And if we wished to stop acid rain we could: experimenters have raised tents over groves of trees to demonstrate that if the acid bath ceases a forest will return to normal. Even the radiation from an event as nearly universal as the explosion at the Chernobyl nuclear power plant has begun to fade, and Scandinavians can once more eat some of the vegetables they grow. The idea of wildness, then, can survive most of man’s destruction of nature. If the ground is dusty and trodden, we look at the sky; if the sky is smoggy, we travel to some place where it’s clear; if we can’t travel to some place where it’s clear, we imagine ourselves in Alaska or Australia or some other place where it is, and that works nearly as well. Nature is durable in our imaginations. The idea of wildness has outlasted the exploration of the entire globe. Standing in the middle of a grimy English mill town, George Orwell reflected, “In spite of hard trying, man has not yet succeeded in doing his dirt everywhere. The earth is so vast and still so empty that even in the filthy heart of civilization you find fields where the grass is green instead of grey; perhaps if you looked for them you might even find streams with live fish in them instead of salmon tins.”
But now the basis of that faith is lost. The idea of nature will not survive the new, global pollution—the carbon dioxide and the methane and the like. This new rupture with nature is different both in scope and in kind from salmon tins in an English stream. We have deprived nature of its independence, and that is fatal to its meaning. Nature’s independence is its meaning.
If you travel by plane and dog team and snowshoe to the farthest corner of the Arctic and it is a mild summer day, you will not know whether the temperature is what it is “supposed” to be or whether you are standing in the equivalent of a heated room. If the wind is howling and the temperature is twenty below, might it otherwise be forty below? Since most of us get to the North Pole only in our minds, our situation is more like this: if, in July, there’s a heat wave in London, it won’t be a natural phenomenon. It will be a man-made phenomenon—an amplification of what nature intended, or a total invention. Or it might be a man-made phenomenon, which amounts to the same thing. The storm that could have snapped the hot spell may never form, or may veer off in some other direction—not by the laws of nature but by the laws of nature as rewritten by man. If the sun feels sweet on the back of your neck, well, that’s fine, but it isn’t nature. What has happened is the extinction of summer and its replacement with something else that will be called “summer.” This new summer will retain some of the season’s relative characteristics—it will be hotter than the rest of the year, for instance, and it will be the time of year when crops grow—but it will not be summer, just as even the best prosthesis is not a leg. Those “record highs” and “record lows” that the weathermen are always talking about are meaningless now. They imply a connection between the past and the present which doesn’t exist. And, of course, climate determines an enormous amount of the rest of nature—where the forests stop and the tundra or the prairies begin, where the rain falls and where the arid deserts squat, where the wind blows strong and steady, where the glaciers form, how fast the lakes evaporate, and how high the seas rise.
About half a mile from my house, right at the head of a small lake, the town has installed a street light. It is the only one for miles, and it is a good thing that it is there; without it, a car or two each summer would miss the turn and end up in the drink. Still, it intrudes on the dark. Most of the year, once the summer people have left, there is not another light to be seen. On a starry night, the Milky Way stands out like a marquee; on a cloudy night, you can walk in pitch-black darkness, unable to see even the dog trotting at your side. But then, around a bend, there is the street lamp, breaking up the feeling of the night. And now it is as if we had put a huge lamp in the sky and cast that same prosaic light everywhere.
We will have a hard time accepting this new state of affairs. Even the most far-seeing naturalists of an earlier day failed to comprehend that the atmosphere, the climate, could be dramatically altered. Thoreau, complaining about the logging that eventually destroyed almost every stand of virgin timber between the Atlantic and the Mississippi, said that soon the East “would be so bald that every man would have to grow whiskers to hide its nakedness, but, thank God, the sky was safe.” And John Muir, the Scottish-born explorer of Yosemite, wrote one day in his diary, about following a herd of grazing sheep through the valley, “Thousands of feet trampling leaves and flowers, but in this mighty wilderness they seem but a feeble band, and a thousand gardens will escape their blighting touch. They cannot hurt the trees, though some of the seedlings suffer, and should the woolly locusts be greatly multiplied, as on account of dollar value they are likely to be, then the forests, too, may in time be destroyed. Only the sky will then be safe.” George Perkins Marsh, the first modern environmentalist, who knew over a century ago that cutting down forests was a disastrous idea, wrote, “The revolutions of the seasons, with their alternations of temperature, and of length of day and night, the climate of different zones, and the general condition and movements of the atmosphere and the seas, depend upon causes for the most part cosmical, and, of course, wholly beyond our control.”
Even as it dawns on us what we have done, there will be plenty of opportunity to forget—at least, for a while—that anything has changed. It isn’t natural beauty that is ended; in the same way that smog breeds spectacular sunsets, there may be new, unimagined beauties. What will change is the meaning that beauty carries, for when we look at a sunset we see, or think we see, many things beyond a particular arrangement of orange and purple and rose.
It is also true that this is not the first huge rupture in the globe’s history. Some thirty times since the earth formed, “planetesimals” at least ten miles in diameter and travelling at sixty times the speed of sound have crashed into the earth, releasing perhaps a thousand times as much energy as would be liberated by the explosion of all present stocks of nuclear weapons; such events, some scientists say, may have destroyed up to ninety per cent of all living organisms. Ice ages have come and gone. On a larger scale, the sun has steadily increased its brightness, growing nearly thirty per cent more luminous since life on earth began, forcing that life to keep forever scrambling to stay ahead (a race it will eventually lose, though not for some billions of years). Or consider an example more closely resembling the sharp divide we have now crossed. About two billion years ago, the spread of a particular kind of cyanobacteria caused, in short order, an increase in atmospheric oxygen from one part in a million to one part in five-that is, from one-ten-thousandth of a per cent to twenty-one per cent. Compared with that, the increase in carbon dioxide from two hundred and eighty to five hundred and sixty parts per million is as the hill behind my house to Annapurna. “This was by far the greatest pollution crisis the earth has ever endured,” the microbiologist Lynn Margulis writes in “Microcosmos.” Oxygen poisoned most microbial life, which, Margulis points out, “had no defense against this cataclysm except the standard way of DNA replication and duplication, gene transfer, and mutation.” And, indeed, these adaptations produced the successful oxygen utilizing life forms that now dominate the earth.
But each of these examples is different from what we now experience, for they were “natural,” as opposed to man-made. A pint-size planet cracks into the earth; the ice advances and retreats; the sun, by the immutable laws of stars, burns brighter until its inevitable explosion; genetic mutation sets certain bacteria to spewing out oxygen until they dominate the planet—a strictly “natural” pollution.
One could argue that the current crisis, too, is “natural,” since man is part of nature. This echoes the views of the early Greek philosophers who made no distinction between matter and consciousness: nature included everything. The British scientist James Lovelock wrote some years ago that “our species with its technology is simply an inevitable part of the natural scene”; that is, we are little more than mechanically advanced beavers. According to this view, to say that human beings have “ended” nature, or even damaged nature, makes no sense. But it is a debater’s point, a semantic argument. When I say that we have ended nature, I mean not that natural processes have ceased but that we have ended the thing that has—at least, in modern times—defined nature for us: its separation from human society.
That separation has been real. I sit writing here in my office. On the wall facing me is a shelf of reference books, and underneath them a typewriter and a computer. Visible through the window is a steep mountain, with nearly a mile of bare ridge and a pond almost at the peak. The mountain and the office are separate parts of my life; I do not think of them as connected. At night, it’s dark out there; save for the street lamp by the lake, there’s not a light for twenty miles to the west and thirty to the south. But in here the light shines. Its beams stretch a few yards into the night and then falter, turn to shadow and black. In the winter, it’s cold out there, but in here the fire burns until near dawn, and when it dwindles the oil burner kicks in. What happens in here I control; what happens out there has always been the work of some independent force. It is this separate nature I am talking about when I use the word—“nature,” if you like.
Scientists may argue that natural processes still rule, that the chemicals even now trapping the earth’s reflected heat or eating away the ozone or acidifying the rain are proof that nature is still in charge—still our master. Some have talked about God as present in the interstices of the atom, or in the mysteries of quantum theory, or in the double helix of DNA and other bits of “information.” To all but the few who really understand the math, though, this is a minor and second hand comfort—an occult, esoteric knowledge. We draw our lessons from what we can see and feel and hear around us. The nature that matters is not the whirling fuzziness of electrons and quarks and neutrinos, which will continue unchanged; it is not the vast fields and fluxes that scientists can find with their telescopes. The nature that matters is the temperature, and the rain, and the leaves turning color on the maples, and the raccoons around the garbage can.
The invention of nuclear weapons may have marked the beginning of the end of nature; we possessed, finally, the ability to overmaster it, to leave an indelible imprint everywhere, all at once. “The nuclear peril is usually seen in isolation from the threats to other forms of life and their ecosystems, but in fact it should be seen as the very center of the ecological crisis—as the cloud-covered Everest of which the more immediate, visible kinds of harm to the environment are the mere foothills,” Jonathan Schell wrote in “The Fate of the Earth.” And, indeed, at the time he was writing—less than a decade ago—it was hard to conceive of a threat of the same magnitude. Global warming was one obscure theory among many; nuclear weapons were unique—and remain so, if only for the speed with which they work. But the nuclear dilemma is at least open to human reason. We can decide not to use the weapons—even to reduce and perhaps eliminate them. And the horrible power of these weapons, which has been amply demonstrated in Japan and on Bikini and under Nevada and many times in our imaginations, has led us fitfully in that hopeful direction.
By contrast, the various processes that lead to the end of nature have been essentially beyond human thought. Only a few people, for instance, knew that carbon dioxide would warm up the world, and for a long time they were unsuccessful in their efforts to alert the rest of us. Now it is too late—not too late (as I shall discuss) to ameliorate some of the changes, and so perhaps avoid the worst of their consequences. But a shift in weather is inevitable.
Just how inevitable we can see from the remedies that some scientists have proposed to save us—solutions that might bring things back to “normal.” The most natural method anyone has suggested involves growing huge numbers of trees to take carbon dioxide out of the air. Consider, for argument’s sake, a new coal-fired electric-generating station that produces a thousand megawatts and operates at thirty-eight per cent thermal efficiency and seventy per cent availability. To counteract the carbon dioxide generated by that plant alone, you would need to cover the surrounding area to a radius of some fifteen miles with American sycamore trees—a fast-growing species—planted at four-foot intervals and “harvested” every four years. A government forestry expert told the Senate energy committee that, with genetic screening, spacing, thinning, pruning, weed control, fire and pest control, fertilization, and irrigation, net annual forest growth could be “very much higher than at present.” Lay aside for the moment the inconvenient fact that enough forests to sop up merely the American output of carbon dioxide would cover fifty per cent more territory than we actually possess. Would this tree plantation be nature? A walk through an endless glade of evenly spaced sycamores, with the weed-control chopper hovering overhead and the quiet gurgle of the irrigation pipes, represents a fundamental break with our idea of the wild world.
Other proposals are even odder. The Columbia geochemist Wallace Broecker has speculated about the use of “a fleet of several hundred jumbo jets” to ferry thirty-five million tons of sulfur dioxide into the stratosphere annually, in order to reflect sunlight away from the earth. Other scientists recommend launching “giant orbiting satellites made of thin films,” which could cast shadows on the earth, counteracting the greenhouse effect with a sort of venetian-blind effect. To deal with ozone depletion, Dr. Thomas Stix, a professor of physics at Princeton, suggests using a laser to scrub chlorofluorocarbons from the earth’s atmosphere before they have a chance to reach the ozone layer. Dr. Stix calculates that an array of infrared lasers spaced around the world could blast apart a million tons of chlorofluorocarbons a year—a procedure he refers to as “atmospheric processing.” Certain practical problems may hamper these various projects; Dr. Broecker, for instance, points out that injecting large quantities of sulfur dioxide into the atmosphere would increase acid rain and give a pale cast to the blue sky. Still, one or another of them just might work. And perhaps, as Dr. Broecker contends, “a rational society needs some sort of insurance policy on how to maintain a habitable planet.” But even if they do work—even if the planet remains habitable—it will not be the same. The whitish afternoon sky blessed by the geometric edge of the satellite cloud will fade into a dusk crisscrossed by lasers. There is no way to reassemble nature.
The passing of nature as we have known it, like the passing of any large idea, will have its recognizable effects both immediately and over time. In 1893, when Frederick Jackson Turner announced to the American Historical Association that the frontier was closed, no one was aware that the frontier had been the defining force in American life. But in its absence this was understood. One reason we pay so little close attention to the separate natural world around us is that it has always been there and we have presumed that it always would be. As it disappears, its primal importance will become clearer, in the same way that some people think they have put their parents out of their lives, until the day comes to bury them.
Above all else, the world displays a lovely order, an order comforting in its intricacy. And the most appealing part of this harmony, perhaps, is its permanence—the sense that we are part of something with roots stretching back nearly forever and branches reaching forward just as far. Purely human life provides only a partial fulfillment of this desire for a kind of immortality. But the earth and all its processes—the sun growing plants; flesh feeding on these plants; flesh decaying to nourish more plants, to name just one cycle—give us some sense of an enduring role.
John Muir expressed this sense of immortality beautifully. Born to a stern Calvinist father, who used a belt to help him memorize the Bible, Muir eventually escaped to the woods, travelling to the Yosemite Valley of California’s Sierra Nevada. The journal of his first summer there is filled with a breathless joy at the grandeur around him. Again and again in that Sierra June—“the greatest of all the months of my life”—he uses the word “immortality,” and he uses it in a specific way, designed to contrast with his father’s grim and selfish religion. Time ceases to have its normal meaning in those hills: “Another glorious Sierra day in which one seems to be dissolved and absorbed and sent pulsing onward we know not where. Life seems neither long nor short, and we take no more heed to save time or make haste than do the trees and stars. This is true freedom, a good practical sort of immortality.” To someone in a mood like this, space is no more of a limitation than time: “We are now in the mountains and they are in us . . . making every nerve quiver, filling every pore and cell of us. Our flesh -and-bone tabernacle seems transparent as glass to the beauty about us, as if truly an inseparable part of it, thrilling with the air and trees, streams and rocks, in the waves of the sun-a part of all nature, neither old nor young, sick nor well, but immortal.”
Some dim recognition that God and nature are intertwined has led us to pay at least lip service to the idea of “stewardship” of the land. If there is a God, He probably does want us to take good care of the planet, but He may want something even more radical. The Old Testament contains in the book of Job one of the most far-reaching defenses ever written of wilderness—of nature free from the hand of man. The argument gets at the heart of what the loss of nature will mean to us. Job is, of course, a just and prosperous man brought low. He refuses to curse God, but he does demand a meeting with Him and an explanation of his misfortune. Job refuses to accept the reasoning of his orthodox friends—that he has unknowingly sinned and is therefore being punished. Their view—that the earth revolves around man, and every consequence is explained by man’s actions—doesn’t satisfy Job, because he knows he is innocent.
Finally, God arrives, a voice from the whirlwind. But instead of engaging in deep metaphysical discussion He talks at some length about nature, about creation. “Where were you when I laid the earth’s foundation?” He asks. In an exquisite poem He lists His accomplishments, His pride in His creation always evident. Was Job there when He “put the sea behind closed doors”? Job was not; therefore, Job cannot hope to understand many mysteries, including why rain falls “on land where no one lives, to meet the needs of the lonely wastes and make grass sprout upon the ground.”
“Behold now Behemoth,” God roars. “He eateth grass as an ox. Lo now, his strength is in his loins. And his force is in the muscles of his belly. He moveth his tail like a cedar. . . . His bones are as tubes of brass. His limbs are like bars of iron. . . . Behold, if a river overflow he trembleth not. He is confident, though Jordan swell even to his mouth. Shall any take him when he is on the watch, or pierce through his nose with a snare?” The answer, clearly, is no: not all nature is ours to subdue.
Nature has provided a way for us to recognize God, and to talk about who He is—even, as in Job, a way for God to talk about who He is. So what will the end of nature as we have known it mean to our understanding of God and of man? For those of us who have tended to locate God in nature—who look upon spring, say, as a sign of His existence and a clue to His meaning—what does it mean that we have destroyed the old spring and replaced it with a new one, of our own devising? We as a race turn out to be stronger than we suspected—much stronger. In a sense, we turn out to be God’s equal, or, at least, His rival—able to destroy creation. This idea has been building for awhile. “We became less and less capable of seeing ourselves as small within creation, partly because we thought we could comprehend it statistically, but also because we were becoming creators, ourselves, of a mechanical creation by which we felt ourselves greatly magnified,” the essayist Wendell Berry writes. “Why, after all, should one get excited about a mountain when one can see almost as far from the top of a building, much farther from an airplane, farther still from a space capsule?” And our nuclear weapons obviously created the possibility that we could exercise godlike powers. But the possibility is different from the fact. Though we seem to have recognized the implications of nuclear weapons and begun to back away from them, we have shown no such timidity in our wholesale alteration of nature. We are in charge now, like it or not. When God asks, as He does in Job, “Who shut in the sea with doors . . . and prescribed bounds for it?” and “Who can tilt the waterskins of the heavens?” we must now answer that it is us.
With this new power comes a deep sadness. I took a day’s hike last fall, following the creek that runs by my door to the place where it crosses the main county road. It’s a distance of maybe nine miles as the car flies, but rivers are far less efficient, and endlessly follow time-wasting, uneconomical meanders. The creek cuts some fancy figures, and so I was able to feel a bit exploratory—a budget Bob Marshall. In a strict sense, it wasn’t much of an adventure. I stopped at the store for a liverwurst sandwich at lunchtime, the path was generally downhill, the temperature stuck at an equable fifty-five degrees, and since it was the week before the hunting season opened I didn’t have to sing as I walked. It isn’t Yosemite, this small valley, but its beauties are absorbing, and one can say, with Muir on his mountaintop, “Up here all the world’s prizes seem as nothing.”
And so what if it isn’t nature primeval? One of my neighbors has left several kitchen chairs along his stretch of the bank, spaced at fifty-yard intervals, for comfort in fishing. At one old homestead, a stone chimney stands at each end of a foundation now filled by a graceful birch. Near the one real waterfall, a lot of rusty pipe and collapsed concrete testifies to the mill that once stood there. But these aren’t disturbing sights; they’re almost comforting—reminders of the way that nature has endured and outlived and with dignity reclaimed so many schemes and disruptions of man. (A mile or so off the creek, there’s a mine where a hundred and fifty years ago a visionary tried to extract pigment for paint and pack it out by mule and sledge. He rebuilt after a fire; finally, an avalanche convinced him. The path in is faint now, but his chimney, too, still stands, a small Angkor Wat of free enterprise.) Large sections of the area were once farmed; but the growing season is not much more than a hundred days in a good year, and the limits established by that higher authority were stronger than the (powerful) attempts of individual men to circumvent them, and so the farms returned to forest, with only a dump of ancient bottles or a section of stone wall as a memorial. These ruins are humbling sights, reminders of the negotiations with nature which have established the world as we know it.
Changing socks in front of the waterfall, I thought back to the spring of 1987 when a record snowfall melted in only a dozen or so warm April days. A little to the south, a swollen stream washed out a highway bridge, closing the New York Thruway for months. The creek became a river, and the waterfall, normally one of those diaphanous-veil affairs, turned into a cataract. It filled me with awe to stand there then, on the shaking ground, and think, This is what nature is capable of. But as I sat there this time, and thought about the dry summer we’d just come through, there was nothing awe-inspiring or instructive, or even lulling, in the fall of the water. It suddenly seemed less like a waterfall than like a spillway to accommodate the overflow of a reservoir. That didn’t decrease its beauty, but it changed its meaning. It has begun, or will soon begin, to rain and snow when the chemicals we’ve injected into the atmosphere add up to rain or snow—when they make it hot enough over some tropical sea to form a cloud and send it this way. In one sense, I will have no more control over this process than I ever did. But the waterfall seemed different, and lonelier. Instead of a world where rain had an independent and mysterious existence, I was living in a world where rain was becoming a subset of human activity: a phenomenon like smog or commerce or the noise from the skidder towing logs on the nearby road—all things over which I had no control, either. The rain bore a brand: it was a steer, not a deer. And that was where the loneliness came from. There’s nothing here except us.
At the same time that I felt lonely, though, I also felt crowded—without privacy. We go to the woods in part to escape. But now there is nothing except us, and so there is no escaping other people. As I walked in the autumn woods, I saw a lot of sick trees. With the conifers, I suspected acid rain. (At least I have the luxury of only suspecting; in too many places, they know.) And so who walked with me in the woods? Well, there were the presidents of the Midwestern utilities, who kept explaining why they had to burn coal to make electricity (cheaper, fiduciary responsibility, no proof it kills trees), and then there were the congressmen, who couldn’t bring themselves to do anything about it (personally favor, but politics the art of compromise, very busy with the war on drugs), and before long the whole human race had arrived to explain its aspirations. We like to drive, it said, air-conditioning is a necessity nowadays, let’s go to the mall. Of course, the person I was fleeing most fearfully was myself, for I drive, and I’m burning a collapsed barn behind the house next week because it is much the cheapest way to deal with it, and I live on about four hundred times the money that Thoreau conclusively proved was enough, so I’ve done my share to take this independent, eternal world and turn it into a science-fair project.
Our local shopping mall has a club of people who go “mall-walking” every day. They circle the shopping center en masse—Caldor to Sears to J. C. Penney, circuit after circuit, with an occasional break to shop. This seems less absurd to me now than it did at first. I like to walk in the outdoors not solely because the air is cleaner but also because outdoors we venture into a sphere larger than we are. Mall-walking involves too many other people, and too many purely human sights, ever to be more than good-natured exercise. But now, out in the wild, the sunshine on one’s shoulders is a reminder that man has cracked the ozone, that, thanks to us, the atmosphere absorbs where once it released. The greenhouse effect is a more apt name than those who coined it can have imagined. The carbon dioxide and the other trace gases act like the panes of glass of a greenhouse—the analogy is accurate. But it’s more than that. We have built a greenhouse—a human creation—where once there bloomed a sweet and wild garden.
A hurricane draws its might from the heat transferred to the atmosphere when ocean water evaporates. The warmer the ocean’s surface, and the deeper beneath the surface the warm water runs, the more powerful the hurricane. If the sea turns cold a few metres down, the winds will soon churn up that frigid water, and the storm will brake itself. But if the warm water runs deep—and in the tropics it may extend down a hundred and fifty metres or more—the hurricane will continue to build. Under present conditions—tropical ocean-surface temperatures of about 80℉.—Hurricane Gilbert, which formed off the Windward Islands in September of 1988, approached what Kerry Emanuel, a professor of meteorology at the Massachusetts Institute of Technology, has calculated to be the upper limit of intensity for a hurricane. The atmospheric pressure at its center dropped to about eight hundred and eighty-five millibars, and so its wind speed reached two hundred miles per hour. A hurricane can’t get much worse than that—under present conditions. But a rise of three or four degrees in tropical sea surface temperatures could raise the upper limit of hurricane strength. In the middle of these warmer storms, atmospheric pressure could fall to eight hundred millibars; as a result, the destructive potential of a hurricane would grow between forty and fifty per cent—a Gilbert and a half.
In the place of the old nature rears up a new “nature” of our own making. This new nature may not be predictably violent. It won’t be predictably anything, and it will take us a long time to work out our relationship with it, if we ever do. The salient characteristic of this new nature is its unpredictability, just as the salient feature of the old nature was its utter dependability. We are used to thinking of the manifestations of nature—rain or sunshine, say—as devious, hard to predict. And over short time spans and for particular places they are. But on a larger scale nature has been quite constant, and on a global scale it has been a model of reliability.
Virtually all settlement patterns testify to the dependability of nature. Every year during the late summer, the Nile overflows its banks—or did until the Aswan Dam was built. A pilot knows how the air will behave along his flight path—that a tropical air mass in summer over the Southeast will breed thunderstorms. Even extreme events, weather emergencies, have been fairly predictable. Engineers calculate the ability of every drainage and wall to withstand the “hundred-year storm.” Every developer who builds a resort along the coast, every underwriter who insures a ship or a plane does so with a conscious dependence on the reliability of nature. And even more dependent are those of us who rely unconsciously on nature’s past performance. The farmer has always watched for rain, and sometimes his crops have shrivelled, but those of us who do our harvesting at the supermarket never doubt that enough rain will fall on enough farms, and always it has.
It is this very predictability that has allowed most of us in the Western world to forget about nature, or to assign it a new role, as a place for withdrawing from the cares of the human world. In some parts of the globe, nature has been more capricious, withholding the rain one year or two, pouring it down by the lakeful the next, and in those places people think about the weather—about nature—more than the rest of us do. But even in Bangladesh, say, people have known that for the most part nature would support them. We have had what Loren Eiseley called “an old contract, an old promise . . . that nature, in degree, is steadfast and continuous.” And this promise has enabled life to establish itself even in places we think of as harsh, since they have been harsh in a fairly dependable way. That promise was long ago broken for passenger pigeons, and for the salmon who ran into dams on the ancestral streams, and for peregrine falcons, whose eggshells were so weakened by DDT that they couldn’t reproduce. But now it is broken for us, too—nature’s lifetime warranty has expired.
Even if our knack for some sort of adaptation proves hardy—and, after all, boat people moving from Cambodia to Canada experience a much more severe climatic shift than anything the scientists predict—the stress will be continuous, unrelenting, because no one knows how all this will turn out. It will undoubtedly be worst for those already living on the edge, already subject to nature’s whim—out on the floodplains of Bangladesh. But it will affect, at the very least, the mind of each of us. We are not necessarily doomed to suffer some cataclysm, but we can no longer count on not being so doomed. Professor Emanuel points out that there is no certainty that an increase in global warmth will push up tropical ocean temperatures and thus hurricane strength; neither is there any certainty that it won’t. The uncertainty itself is the first cataclysm, and perhaps the most profound. When we can’t depend on enough snow falling to fill the reservoirs that feed our faucets, or when we have to worry about too much of that water evaporating in the heat, then the weather report is going to be leading off the evening newscasts. In the summer of 1988, while America sweltered, scientists on the staff of the Environmental Protection Agency were finishing up the most comprehensive assessment yet made of the possible effects of the climate change. Congress had requested the study two years earlier, and the E.P.A. had done its work diligently, studying four regions in great detail and compiling most of the available literature on the subject. The authors of the report, which was entitled “The Potential Effects of Global Climate Change on the United States,” inserted several caveats. “We have no experience with the rapid warming . . . projected to occur during the next century,” they wrote. “We cannot simulate in a laboratory what will happen over the entire North American continent.” And they added, with ominous modesty, “The results are also inherently limited by our imaginations. Until a severe event occurs such as the drought of 1988, we fail to recognize the close links between our society, the environment, and climate. For example, in this report we did not analyze or anticipate the reductions in barge shipments due to lower river levels, the increases in forest fires due to dry conditions, or the impacts on ducks due to disappearing prairie potholes.”
Let’s look at that last, small item, “the impacts on ducks,” for it sums up many of the lessons of this new, artificial nature. As the changes wrought by man have accelerated, so has the damage to other species. But there have been extensive efforts in recent years to save enough nature to accommodate at least some ducks (and bears and elk and eagles), and—to a certain degree, at least—these efforts have succeeded. In 1988, however, as ducks flew north in the summer they found very little water. Parts of North Dakota were ninety per cent dry, and one aerial survey of the Canadian prairie, Penny Ward Moser reported in Sports Illustrated, showed only seven of three hundred and thirty prairie potholes holding water. The potholes were a product of nature’s slow pace: when the glaciers retreated from the northern Great Plains ten thousand years ago, they left pockmarks. Over the last hundred years or so, men have drained many of them, and the drought of 1988 emptied most of the rest. “The strongest of the early arrivals,” Moser wrote of the ducks, “staked a claim, mated, and tried to raise a clutch in rapidly dwindling waters, surrounded by predators who congregated nearby, anticipating a summer-long feast.” Some ducks took one look and decided to forget about mating; they spent the summer floating unproductively on larger lakes. Others flew farther north and arrived finally at usable habitat, but by then they were too protein-starved to produce eggs. Meanwhile, ducks that had found marshes to nest in, and had survived the lurking predators, began to contract botulism. In the warm and shallow water, it became an epidemic. Other ducks—many other ducks—died when the United States Department of Agriculture, in an attempt to aid drought-stricken farmers, released millions of acres of “set aside” and conservation land they had paid the farmers not to touch. As the tractors roared through, nests and ducks were mowed and baled along with the hay. Millions of fish were dying, too, as temperatures soared in streams and lakes and as lowering water levels made fish more vulnerable to pesticides. Moser, on the farm in northern Illinois where she grew up, wrote, “We see no great blue herons in our streams this summer. There are barely any streams at all. The muskrats’ underwater tunnels are high in the banks above the water. . . . Hanging over a culvert along the road, we watch some minnows wriggle over mud shallows looking for a deeper pool. Then the minnows reverse direction, pushing over the mud again, back to where they had been. This is the deeper pool.”
Nature has always provided, as the Cape Cod essayist Robert Finch put it, the “deep, constant rhythms,” even if we have come to think that we are independent of its pulses. We still rely on the earth’s “basic integrity and equanimity” to give us a “safe and stable context,” Finch writes, and, in particular, we rely on the seasons. “The recurring cycles of the year . . . are not simply entertaining phenomena, to be noted at our convenience and for our enjoyment,” he writes, “but signs that the cosmos is still intact, that we remain included in something larger and more reliable than our own short-lived enthusiasms. It is for this that we need to know that insects will hibernate, that turtles and warblers will migrate and return, that the tide will retreat, the ice let go, the earth tilt back toward the sun, and the grass reawaken.” Despite dozens of new ways to look at the world—the genetic, the microscopic, the chemical—we are still very much the same people who built Stonehenge to make sure each year that the sun really did begin its retreat, the same people who trembled at eclipses. We need to be able to worry about our human affairs secure in our knowledge of the eternal inhuman. The certainty of nature—that God’s creation or Darwin’s or whoever’s will provide for us, bountifully, as it always has—is what frees us to be fully human, to be more than gatherers of food.
The single most talked-about consequence of a global warming is probably the expected rise in sea level as a result of polar melting. For the last several thousand years, sea level has been rising, but so slowly that it has almost been a constant. In consequence, people have extensively developed the coastlines. But a hundred and twenty thousand years ago, during the previous interglacial period, sea level was twenty feet above the current level; at the height of the last ice age, when much of the world’s water was frozen at the poles, sea level was three hundred feet below what it is now. Scientists estimate that the world’s remaining ice cover contains enough water so that if it should all melt it would raise sea level more than two hundred and fifty feet. This potential inundation is stored in the Greenland Ice Sheet (if it melts, it will raise the world’s oceans twenty-three feet), the West Antarctic Ice Sheet (another twenty-three feet), and East Antarctica (more than two hundred feet), with a smaller amount—perhaps half a metre—in the planet’s alpine glaciers. (Melting the ice currently over water, such as the sea ice of the Arctic Ocean, won’t raise sea level, any more than a melting ice cube overflows a gin-and-tonic.) The East Antarctic is relatively safe; the direst fears of a rising sea came as the result of a 1968 study concluding that the Ross and Filchner-Ronne ice shelves, which support the West Antarctic Ice Sheet, could disintegrate within forty years. Subsequent investigations, however, seem to have demonstrated that such a disintegration would take at least two centuries, and probably more like five (though several investigators have speculated that it might become irreversible within the next century).
But the salvation of the West Antarctic does not mean the salvation of Bangladesh, or even of East Hampton. A number of other factors may raise sea level significantly. Glaciers bordering the Gulf of Alaska, for example, have been melting for decades, and constitute a source of fresh water about the size of the entire Mississippi River system. And even if nothing at all melted, the increased heat would raise sea level considerably. Warm water takes up more space than cold water; this thermal expansion, given a global temperature increase of between one and a half and five and a half degrees Celsius, should raise sea level a foot, according to James Hansen. It is by now widely accepted that sea level will rise significantly over the next decades. The E.P.A. has estimated that it will rise between five and seven feet by 2100, and speculated about worst-case scenarios that might lead to an eleven foot rise; the National Academy of Sciences has been more conservative; other researchers have turned in even scarier numbers. Suffice it to say that included in the range of guesses of almost every panel and scientist studying the problem is an increase in global sea level of better than three feet over the next century.
That may not sound like very much, but it means that the sea would reach a height unprecedented in the history of civilization. The immediate effects of the swollen sea would be seen in a place like the Maldives. By most accounts, this archipelago of eleven hundred and ninety small islands about four hundred miles southwest of Sri Lanka is fairly paradisal. Its residents had never heard a gun fired in anger until last year, when a short-lived coup attempt was mounted by foreign mercenaries. They survived the downturn in the coir business (coir is an elastic fibre made from coconut husks); breadfruit and citron trees are abundant. But most of this happy nation rises only two metres above the Indian Ocean. If sea level were to rise one metre, storm surges would become an enormous, crippling danger; were it to rise two metres—well within the range of possibilities predicted by many studies—the country would all but disappear. In October of 1987, the Maldivian President, Maumoon Abdul Gayoom, went before the United Nations General Assembly. He described his country as “an endangered nation.” The Maldivians, he pointed out, “did not contribute to the impending catastrophe . . . and alone we cannot save ourselves.” A map drawn a hundred years from now may not show the Maldives at all, except as a danger to mariners.
Other nations, though not extinguished, would be very badly hurt. A two-metre rise in sea level would flood twenty per cent of the land in Bangladesh, much of which is built on the floodplains at the mouth of the Brahmaputra. In Egypt, such a rise would inundate less than one per cent of the land, but that area constitutes much of the Nile Delta, where most of the population lives. Nor is the danger only to the Third World. Several years ago, the E.P.A. distributed a worksheet to allow local governments to calculate their future position vis-à-vis the salt water. In Sandy Hook, New Jersey, for instance, add thirteen inches to the projected increase in sea level to account for local geologic subsidence, for a net ocean rise, in the next hundred years, of four feet one inch. In Massachusetts, between three thousand and ten thousand acres of oceanfront land worth between three billion and ten billion dollars might disappear by 2025, and that figure does not include land lost to encroaching ponds and bogs as the rising sea lifts the water table. But storm surges would do the most dramatic damage: in Galveston, Texas, ninety-four per cent of the land is within the plain that would be flooded by the worst storms. Such surges are the reason that Holland built many of its protective dikes. The most extensive barriers went up after the winter of 1953, when a surge breached the existing dikes in eighty-nine places along the central delta, killing nearly two thousand people and tens of thousands of cattle. Afterward, the Dutch decided to spend more than three billion dollars building new defenses.
As the Dutch effort indicates, much can be done to defend against increases in sea level. The literature abounds with studies of how much it would cost to protect coastal areas. The trouble is, spending the money to protect the shoreline would lead to ecological costs harder to calculate but easy to understand. Coastal marshes or wetlands exist in a nearly unbroken chain along the Gulf and Atlantic Coasts of the United States. Protected from the waves of the ocean by barrier islands or peninsulas, they are part land and part water, and are home to an abundance of plants and animals. They are more biologically productive than either the ocean or the dry land, in part because tidal flows spread food and flush out waste, it is a cycle that encourages quick growth and rapid decay. These communities support an immense variety of birds, fish, shellfish, and plants. Early settlers (with noble exceptions, like William Bartram) thought coastal marshes “miasmal,” and drained or filled many of them. In recent years, federal and state authorities have grudgingly begun to protect them. As King Canute demonstrated, however, the ocean disregards governments, and as its level rises the area of the wetlands will dwindle. This is not axiomatic: if the marsh has room and time enough to back up, it will, and the drowned wetland will be replaced by a new one. But, as another recent E.P.A. report pointed out, “in most areas . . . the slope above the marsh is steeper than the marsh; so a rise in sea level causes a net loss of marsh acreage.” That is, in many cases the marsh will run into a cliff it can’t climb. In a number of places, the cliffs will be man-made. If I have a house on Cape Cod, and my choice is to build a wall in front of it or let a marsh come in and colonize my basement, I will probably build the wall.
Should the ocean go up a metre, at least half the nation’s coastal wetlands will be lost one way or another. “Most of today’s wetland shorelines still would have wetlands,” according to the E.P.A. report to Congress. “The strip would simply be narrower. By contrast, protecting all mainland areas would generally replace natural shorelines with bulkheads and levees.” The relentlessly practical authors add that “this distinction is important because for many species of fish, the length of a wetland shoreline is more critical than the total area.” It’s also important if you are used to the idea of the ocean meeting the land with ease and grace instead of bumping into an endless concrete wall.
There are other reasons to fear a sea-level rise. In normal times, the water pouring out of a river pushes the ocean back. But in a drought the reduced flow creates a vacuum that the sea oozes in to fill. The “salt front” advances. In the drought of the nineteen-sixties, it nearly reached the point in the Delaware River where Philadelphia’s water intake is located. During a drought, New York City must release vast quantities of water from its reservoirs on the upper Delaware to keep the salt front from creeping upriver. New Yorkers, however, continue to take showers and wash their hands. In the summer of 1985, city officials made up for the diminished flow from reservoirs by pumping water straight from the Hudson. This worked well—the water turned out to be considerably cleaner than many had expected—except that as the flow of the Hudson was reduced the salt front began to move up that river, and the town fathers of Poughkeepsie grew worried about their supply’s getting salty. As the greenhouse warming kicks in, increased evaporation could steal from ten to twenty-four per cent of the water in New York’s reservoirs, the E.P.A.’s 1988 report continues. In addition, a one-metre sea-level rise could push the salt front up past the city’s water intake on the Hudson. In all, the report observes, “doubled carbon dioxide could produce a shortfall equal to twentyeight to forty-two per cent of planned supply in the Hudson River Basin.”
The expected effects of sea-level rise typify the many other consequences of a global warming. On the one hand, they are of such magnitude that we can’t grasp them. If there is significant polar melting, the earth’s center of gravity will shift, tipping the globe in such a way that sea level might actually drop at Cape Horn and along the coast of Iceland. (I read this in the E.P.A. report and found that I didn’t really know what it meant to tip the earth, though I was awed by the idea.) On the other hand, the changes ultimately acquire a quite personal dimension: Should I put a wall in front of my house? Does this taste salty to you? What’s more, many of the various effects of the warming compound one another. If the weather grows hotter and I take more showers, more water must be diverted from the river, and the salt front moves upstream, and so on. The complications multiply almost endlessly (more air-conditioning means more power generated means more water sucked from the rivers to cool the generators means less water flowing downstream, et cetera ad infinitum). These aren’t the simple complexities of, say, last summer, when everyone on the East Coast rushed to the beaches to escape the hot weather, only to discover a tide of syringes and fecal matter. These complexities are the result of throwing every single natural system into an uproar at the same time, so that none of nature’s reliable compensations can be counted on. For example, at the same time that sea level is increasing, and the warmer air is gathering up more water vapor and presumably increasing the over-all precipitation, the temperature is continuing to go up. The result, the computer modellers say, will be greatly increased levels of evaporation; in many parts of the world, there will be a drier interior to complement the sodden coasts.
It’s not simply a matter of heat. If the temperature rises, the number of days with snow cover will likely fall. When the snow-melting season ends, more of the sun’s energy is absorbed by the ground instead of being reflected back to space, and, as a result, the soil begins to dry out. In the greenhouse world, this seasonal change will begin earlier, because the snow will melt faster. In some areas, other weather changes may offset the evaporation. Roger Revelle, of the Scripps Institution, has estimated that flows in the Niger, the Senegal, the Volta, the Blue Nile, the Mekong, and the Brahmaputra would increase—probably with disastrous results in the last two cases—whereas flows might diminish in the Hwang Ho, in China; the Amu Darya and the Syr Darya, which run through the Soviet Union’s principal agricultural areas; the Tigris-Euphrates system; and the Zambezi. The United States, as usual, has been most closely studied. America is blessed with ample water; on an average day, four trillion two hundred billion gallons of precipitation fall on the lower forty-eight states. Most of that water evaporates, leaving only about one trillion four hundred and thirty-five billion gallons a day, of which in 1985 only about three hundred and forty billion gallons a day were withdrawn for human use. It seems like more than enough. However, as anyone who has ever flown across the nation (and looked out the window) can attest, the water is not spread evenly. In its report to Congress, the E.P.A. notes that total water use exceeds average stream flow in twenty-four of the fifty-three Western water-resource regions, a difference made up by “mining” groundwater stocks and importing water. Much of the Colorado River’s flow, for example, is dammed, diverted, and consumed by irrigation projects and by the millions upon millions of people living in places that would otherwise be too dry.
And matters may get worse. After studying the temperature and streamflow records, Revelle and the climatologist Paul Waggoner concluded that if a “conservative,” two-degree-Celsius increase in temperature occurs, the virgin flow of the Colorado could fall by nearly a third; the same study predicts that if, as some of the computer models suggest, this temperature rise is accompanied by a ten-per-cent decrease in precipitation in the Southwest because of new weather patterns, runoff into the upper Colorado could fall by forty per cent. Even if rainfall went up ten per cent, the runoff would still drop by nearly twenty per cent. Across the West, the picture is similar: in the Missouri, Arkansas, lower-Colorado, and Rio Grande irrigation regions, supply could fall by more than half. In the Missouri, Rio Grande, and Colorado basins, the estimated water needs in the year 2000 could not be met by stream flows after the expected climatic changes. One model predicts a twenty-five-per-cent increase in the demand for irrigation water from the Ogallala Aquifer, the subterranean lake that irrigates the Great Plains and is already badly depleted.
A compelling question is what all this means for agriculture. The answer comes on several levels, the first being that of the individual plant. Quite apart from heat and drought, the simple increase of atmospheric carbon dioxide affects plants. Ninety per cent of the dry weight of a plant comes from the conversion of carbon dioxide into carbohydrates by photosynthesis. If nothing else limits a plant’s growth—if it has plenty of sunshine, water, and nutrients—then increased carbon dioxide should increase the yield. And in ideal laboratory conditions this is what happens; as a result, some journalists have rhapsodized about “supercucumbers” and found other green linings to the cloud of greenhouse gases. But there are drawbacks. If some crops grow more quickly, farmers may need to buy more fertilizer, since leaves may become richer in carbon but poorer in nitrogen, reducing food quality not only for human beings but for nitrogen-craving insects, who may eat more leaf to get their fix. In the best case, direct effects of increased carbon dioxide on yield are expected to be small; the annual harvest of well-tended crops might rise about five per cent when the carbon-dioxide level reaches four hundred parts per million, all other things being equal.
But all other things won’t be equal. All other things—moisture, temperature, growing season—will be different. It is an obvious point, but worth repeating: most of what we eat spends its growing life in the open air, “exposed,” in the words of Paul Waggoner, “to the annual lottery of the weather.” About fifty million acres of America’s cropland and rangeland are irrigated, but even those fields depend on the weather over any long stretch. And we can’t just stick the wheat crop under glass.
It is a tricky business trying to predict what changes in the weather will do to crops. A longer growing season—the period between killing frosts—surely helps; a lack of moisture surely hurts. If temperatures stay warm, plants grow nicely. If temperatures get really hot, they wither. (A long stretch above ninety-five degrees Fahrenheit, for instance, can sterilize corn.) The climate models are too crude to project with any precision what will happen in a given area, and too many variables make even the broadest predictions difficult. The severe droughts of the Dust Bowl years provide scant guidance: on the one hand, the technological revolution in agriculture has tripled yields since then, but on the other, as a government report notes, “the economic robustness associated with general multiple-enterprise farms has long since passed from the scene on any significant scale,” and therefore “the current vulnerability of our agricultural system to climate change may be greater in some ways than in the past.” Most of the experts have simply thrown up their hands. The best guesses seem to be that the northern reaches of the Soviet Union and Canada will be able to grow more food and the Great Plains of the United States less—not so little that America couldn’t feed itself but enough below present production so that United States food exports, which earn the country some forty billion dollars in a good year, might fall by seventy per cent. “It has been suggested,” Stephen Schneider told the Senate energy committee last year, “that a future with soil-moisture change . . . would translate to a loss of comparative advantage of United States agricultural products on the world market”—a sentence to make an economist shiver on an August day.
This sounds like somewhat comforting news—as if we would still have enough to eat—but when computers are modelling something as complex as all of agriculture the potential for error is enormous (or the potential for accuracy is small). The effect of the heat and drought of 1988 made liars of most of the computer models in just a few weeks. They had concluded that the expected doubling of carbon dioxide in several decades might make the weather hot and dry enough to cut American corn and soybean yields as much as twenty-seven per cent, but in the summer of 1988, when the rains held off, the American corn crop fell thirty per cent—down by about two and a half billion bushels.
Even if, as seems likely, that heat wave had little to do with the greenhouse effect, we now have some idea what it will feel like once it is here. As of late August, the grain stored around the world amounted to only about two hundred and eighteen million metric tons—enough to last forty-seven days, and the lowest level since 1973. Worldwide consumption of grain outpaced worldwide production by sixty million metric tons last year. You can live with a budget deficit for quite a while, but when the food runs out there’s no central bank to mint some more.
The thing to remember is that all these changes may be happening at once. It’s hotter, and it’s drier, and sea level is rising as fast as food prices, and hurricanes are strengthening, and so on. And not least is the simple fact of daily life in a hotter climate. The American summer of 1988, when no one talked about anything but the heat and how soon it would end, was only a degree or two warmer, on average, than what we were used to. But the models predict that summers could eventually be five or six or seven degrees warmer than the old “normal.” Science has yet to devise a way of determining what percentage of people feel like human beings on any given August afternoon, or the number of work hours lost to the third cold bath of the day—or, for that matter, the loss of wit and civility in a population concerned mainly with keeping its shirts dry. These are important matters, and a future full of summers like that one is a grim prospect. Summer will come to mean something different—not the carefree season anymore but a time to grit one’s teeth and get through. To anyone who lived through the 1988 heat it seems unlikely that people will simply get used to it.
A certain number of people who didn’t get used to the heat died of it. Public-health researchers have correlated mortality and temperature tables. When the weather gets hot, they find, preterm births and perinatal deaths both rise. Mortality from heart disease goes up during heat waves, and emphysema gets worse. If, the E.P.A. notes, in its 1988 report to Congress, “climate change encourages a transition from forest to grassland in some areas, grass pollens could increase,” worsening hay fever and asthma. “A variety of other U.S. diseases indicate a sensitivity to changes in weather,” the report continues. “Higher humidity may increase the incidence and severity of fungal skin diseases (such as ringworm and athlete’s foot), and yeast infections (candidiasis). Studies on soldiers stationed in Vietnam during the war indicated that outpatient visits for skin diseases (the largest single cause of outpatient visits) were directly correlated to increases in humidity.”
That last sentence suggests that a useful place to look for information about American weather might be Vietnam. There is nothing wrong with the Vietnamese climate—it is not “better” or “worse” than the various American climates, or the weather in Britain, or the cold of Canada. And people have been able to move back and forth between all these zones, adapting to conditions. In fact, we often want to—a change of climate is perhaps the single biggest inducement to travel. But now the climate is travelling. A recent United Nations study estimates that sometime in the next century the climate of Finland will have become similar to that of northern Germany, that of southern Saskatchewan to northern Nebraska, of the Leningrad region to the western Ukraine, of the central Urals to central Norway, of Hokkaido to northern Honshu, and of Iceland to northeast Scotland. If we felt like keeping the weather we’re accustomed to, it’s we who would have to move, travelling north ahead of the heat.
The list of miscellaneous circumstances that might result from changes in the atmosphere looks to be infinite. In New York City, the heat of the summer of 1988 softened asphalt and caused thousands of “hummocks”—potholes in reverse—in the streets. “When it’s over ninety degrees for a prolonged period of time, the problem is virtually out of control,” Lucius Riccio, of the New York City Bureau of Highway Operations, told the Times. Steel expansion joints buckled along Interstate 66 around Washington, D.C., during the heat wave, and a hundred and sixty people were injured when a train derailed in Montana, apparently because the heat warped the rails. Coupled with the physical predictions are endless political and financial conjectures. Francis Bretherton, of the National Center for Atmospheric Research, told Time that if the Great Plains became a dust bowl and people followed the seasonable temperatures north, Canada might replace the United States as the Western superpower.
This game swings from the specific to the wildly speculative. There is no easy way to say that something can’t happen or is unlikely to happen; forecasts have to be based on the past, and there is no longer a relevant past. Jesse Ausubel, the director of programs at the National Academy of Engineers, told Fortune that it “may become difficult to find a site for a dam or an airport or a public transportation system or anything designed to last thirty to forty years,” and asked, “What do you do when the past is no longer a guide to the future?” We are left with a vast collection of “mights,” and only one certainty: we have changed the world, and therefore some of the “mights” are inevitable. I find myself thinking often of some purple-martin chicks that Penny Moser found “cooked to death” near her Illinois farm in 1988’s heat. This was an actual event and also a metaphor. The heat will cook the eggs of birds, and that destruction—and the hurricanes and the rising sea and the dying forests—will rob us of our sense of security. That the temperature had never reached a hundred degrees at the airport in Glens Falls, the city nearest my home, made it a decent bet that it never would. And then, in July of 1988, it did. There is no good reason anymore to say that it won’t reach a hundred and ten degrees. The old planet is a different planet. There is no reason to feel secure, because there is no reason to be secure.
Last summer, I paddled across a northern Adirondack lake with a state biologist to visit an eagle’s nest. Thirty years before, in an effort to curb black flies, communities in this area put big blocks of DDT in the streams. The black flies survived (they hung in clouds around us the whole morning), but the eagles, among others, didn’t. The chemical thinned the shells of their eggs; when the mother eagles sat on the eggs, the shells collapsed. Finally, last year, three pairs of eagles returned to the Adirondacks and built nests. We sat in the canoe and watched a big eagle circle above us with patient irritation, head ruffled. His mate was on the nest, and we were too close. He swooped nearby; we backed off; he rose with a beat or two of his six-foot wingspan and flew for the nest. When he got there, he flared his wings, stalled, and dropped softly down.
Had Rachel Carson not written when she did about the dangers of DDT, it might well have been too late by the time anyone cared about what was happening. She pointed out the problem; she offered a solution; the world shifted course. That is how this discussion should end, too. At this writing, the greenhouse effect shows every sign of becoming an important political issue. President George Bush has called for an international scientific workshop on the subject; there is talk of drawing up an international treaty on climate change modelled on the recent international accords to phase out production of chlorofluorocarbons. It all sounds promisingly rational. We ought to come up with a good practical response, a plan, a series of steps, a seven-point proposal to offset the greenhouse effect. That is our reflex. The minute the scientists at the June, 1988, congressional hearings finished explaining that we were heating up the earth, senators began talking about nuclear power; it was literally their first reaction. Senator Frank Murkowski, of Alaska, asked, “Is it indeed a reality that we must look more aggressively to nuclear as a release? Because I don’t see the public demanding any reduction in the power requirements that our air-conditioners run off of, everything else that we enjoy.” Not even the senator from Alaska can imagine life without air-conditioning, so we must come up with some solution, and fast. But is nuclear power a solution? Lay aside the questions of whether it’s safe and what we will do with the resulting waste (though it is a sign of the depth of our addiction that we would be willing to lay aside such considerations). Nuclear energy is, at the moment and for the foreseeable future, useful for generating electricity but not for, say, powering my Honda. We may well need to swallow our fears about safety and build more reactors, but doing so won’t make everything all right. Returning to the same mix of natural gas and coal that America used in 1973 could save as much carbon dioxide as expanding nuclear power fifty per cent. And we have no spare decades in which to build more Shorehams and Seabrooks; putting off the solution twenty or thirty or forty years would give us thirty or forty or sixty more parts per million of carbon dioxide.
But what about increasing efficiency—what about conservation? There is—no question—waste, even sixteen years after the energy crisis. For example, most of the electricity consumed by industry is used to drive motors; companies, anticipating expansion, tend to buy larger motors than they need; however, large motors are inefficient when they run at less than full speed. The latest edition of the World Resources yearbook estimates that if every industrial motor in the United States were to be equipped with available speed-control technology America’s total electricity consumption would fall seven per cent. We must end waste, the sooner the better. But will this kind of action solve the problem? Consider a few numbers supplied by Irving Mintzer, of the World Resources Institute. He describes a “base case” scenario that “reflects conventional wisdom in its assumptions about technological change, economic growth, and the evolution of the global energy system.” In this model, nations do not enact policies to slow carbon-dioxide emissions, nor do they provide more than minimal support for increased energy efficiency and solar research and development, though they do slow the rate of chlorofluorocarbon production. The result is an average global warming of up to 4.7℉. by the year 2000, and of up to 8.5℉. by 2030. This, Mintzer says, “is by no means the worst possible outcome.” If the use of coal and synthetic fuels is encouraged, and tropical deforestation continues to increase, the planet would be doomed to an increase of up to 12.6℉. by 2030, and, by 2075, to a nearly thirty-degree jump—a level with implications too sci-fi for us to imagine. The good news, such as it is, concerns Mintzer’s “slow buildup scenario.” In this one, strong international efforts to reduce greenhouse gas emissions “eventually stabilize the atmosphere’s composition.” Coal, gas, and oil prices are markedly increased, per-capita energy use declines in industrialized countries, and governments actively pursue the development of solar energy. The world embarks on “massive” reforestation efforts. And so on. If all these heroic efforts had begun in 1980, by 2075 we would experience a warming of between 2.5℉. and 7.6℉., which is still “greater than any experienced during recorded human history.”
Carbon dioxide and other greenhouse gases come from everywhere, so the situation they create can be fixed only by fixing everything. Small substitutions and quick fixes are not the answer. One common suggestion is to replace much of the coal and oil we burn with methane, since it produces considerably less carbon dioxide. But, as I have noted, any methane that escapes unburned into the atmosphere traps solar radiation twenty times as efficiently as carbon dioxide does. And methane does leak—from wells, from pipelines, from appliances; some estimates suggest that as much as three per cent of the natural gas tapped in this country escapes unburned. So converting from oil to natural gas might make the situation worse. The size and complexity of the industrial system we have built makes even small course corrections physically difficult.
Not only is that system huge but the trend toward growth is incredibly powerful. At the simplest level—population—the increase continues, if not unabated, then only slightly abated. In some of the developing countries, thirty-seven per cent of the population is under fifteen years of age; in Africa, the figure is forty-five per cent. Without a static population, even the most immediate and obvious goals, like slowing deforestation or reducing fossil-fuel use, seem far-fetched. Over the last century, a human life has become a machine for burning petroleum. At least in the West, the system that produces excess carbon dioxide is not only huge and growing but also psychologically all-encompassing. It makes no sense to talk about cars and power plants and so on as if they were something apart from our lives-they are our lives. Moreover, for any program to be a success we must act not only as individuals and as nations but as a community of nations. The trouble is, though, that some countries may perceive themselves to be potential winners in a climatic change. The Russians may decide that the chance of increased harvests from a longer growing season is worth the risk of global warming. And the United States, the Soviet Union, and China own about two-thirds of the world’s coal reserves, so anyone of them can scuttle progress. The possibilities of other divisions—rich nations versus poor nations, say—are large. Every country has its own forms of despoliation to protect; the Canadians, for instance, who complain loudly about their position as helpless victims of American acid rain, are cutting down the virgin forests of British Columbia at an almost Brazilian pace. And the fact that decisions must be made now for the decades ahad means that, in the words of Richard Benedick, our Deputy Assistant Secretary of State for Environment, Health, and Natural Resources, “somehow, political leaders and government processes and budget-makers must accustom themselves to a new way of thinking.” Of all the quixotic ideas discussed here, that may top the list.
The greenhouse effect is often compared to the destruction of the ozone layer, another example of atmospheric pollution with global implications. But the destruction of the ozone layer can and likely will be solved by our ceasing to produce the chemicals currently destroying it. Though this step won’t end the problem overnight, it will take care of it eventually. And, though the necessary international negotiations may be complex, steps like this are easy enough so that they will certainly be taken. Essentially, it’s like controlling DDT. The problem of global warming, however, does not yield to the same sort of solution. With aggressive action—as Mintzer’s numbers indicate—we can “stabilize” the situation at a level that is only mildly horrific, but we cannot solve it.
This is not to say that we should not act. We must act, and in every way possible, and immediately. We stand at the end of an era—the hundred years’ binge of oil, gas, and coal which has given us both the comforts and the predicament of the moment. Even those countries which wouldn’t object to a degree or two of warming for a longer growing season can’t endure endless heating. The choice of doing nothing—of continuing to burn ever more oil and gas and coal—is not a choice. It will lead us, if not straight to hell, then straight to a place with a comparable temperature. But even the scientists calling most vociferously for controls on emissions say they are doing so in order to slow down the warming so that we can adapt to it. That adaptation is all that remains to be discussed.
Adjustment to the greenhouse world will not be easy; our addiction to oil is deep. Our every comfort—especially the freedom from hard labor, for those of us who enjoy such freedom—depends on fossil fuels. They allowed us to dominate the earth, instead of letting the earth dominate us. Our impulse will be to adapt not ourselves but the earth—to figure out a new way to continue our domination, and hence our accustomed life styles, our hopes for our children. This defiance is our reflex. Our impulse will be to defy the doomsayers and press ahead into a new world.
The futurist Julian Simon has infuriated environmentalists by predicting that before we ran out of anything essential, scientists would discover new ways to produce it; if we started to run out of copper, say, we would find out how to make it from other metals. In a 1981 book called “The Ultimate Resource,” he writes that with knowledge, imagination, and enterprise “we can manipulate the elements in such fashion that we can have all the mineral raw materials that we need and desire at prices ever smaller relative to other prices and to our total incomes. In short, our cornucopia is the human mind and heart.”
This is not a scientific treatise—Simon has not discovered how to produce copper from other metals. It is, despite its reliance on “long-run economic indicators” and such, a religious argument, an article of faith. “The main fuel to speed our progress is our stock of knowledge, and the brake is our lack of imagination,” he writes. “To have more children grow up is also to have more people who can find ways to avert catastrophe.” The religiosity of this view can be seen as well in books like “The Hopeful Future,” of 1983, whose author, G. Harry Stine, argues that to make predictions based on current rates of growth and progress is absurd. Even a curve that shows the rate of human progress as increasing from its present mind-boggling pace is too conservative. Only “Curve E,” a “cubic curve that continues to turn upward ever more steeply with no limit in sight,” makes sense. “It means that we can expect eight times as much progress in the next fifty years as we have seen in the past fifty,” he says. This is not, strictly speaking, blind faith; the optimists can explain their reasoning. But it is faith, and it comes with other religious trappings—a dark view of people who think differently, for instance. (“Some of the ‘futurists’ making ‘downside’ forecasts don’t like people. That means they don’t like themselves either,” Stine chides.) And there is a vision of a not too distant utopia. In the twenty-first century, Stine writes, enormous orbiting satellites will beam down “enough energy for everybody to do everything.”
I am not dismissing the futurists. On the contrary, I think it possible that they are right: we can keep progressing, even in the teeth of the greenhouse effect. We will invent new tools, new technologies, to keep ourselves alive on the planet. We will figure out ways to extend our control so far that not even the rogue nature we have inadvertently created in our last century of progress will escape our domination. I can imagine scenarios—a nuclear war, for instance—that would cancel this future. But my guess is that the defiant optimists are likely correct in their assertion that we can have a “macromanaged” world—one that may well allow us to continue our ways of life even in the face of the coming heat. People with sincere and “progressive” ideas about man’s future profess their hope for such a world. Buckminster Fuller is probably the great example. He was not an enemy of the environment; his geodesic domes, for instance, are as stable as conventional buildings, at about three per cent of the weight. Were we all to live in them, there would be a lot more forests standing.
He was not an enemy of the environment, but he was a champion of man. “We have to deal with our spaceship, Earth, as a machine, which is what it is,” he wrote in “Approaching the Benign Environment.” I doubt whether Fuller would have viewed the end of nature with much trepidation, for he never believed that we would or should stay long in the surroundings we had grown accustomed to. Instead, we were like a chick in a shell. This shell had just enough food in it—enough coal and oil and oxygen and whatever—to allow us to develop to a certain point. “But then, by design, the nutriment is exhausted just at the time when the chick is large enough to be able to locomote on its own legs,” he wrote. “And so as the chick pecks at the shell seeking more nutriment it inadvertently breaks open the shell.” The analogy is somewhat selfish-that there are other species in the shell with us seems not to have crossed his mind—but it may well be correct. As a mild example of our hubris, consider a recent book: “Gaia—An Atlas of Planet Management.” Despite this title, it does not, I think, reflect fully the Gaia hypothesis, which was first outlined by James Lovelock in the nineteen-seventies; namely, that the earth is a self-sustaining, self-regulating organism. Instead, it argues that man should take ever more control of the planet. Its editor, Norman Myers, seems almost thrilled by the current state of affairs. The approaching crises represent “our final evolutionary examination.” We must rise to the occasion, pass the test. And we will: “We are grown up. We have acquired the power of life and death for our planet and most of its inhabitants. . . . Our ‘satellite vision’ means that all the planet’s resources—soils, forests, rivers, oceans, minerals—can be not only mapped in fine detail, but vetted for pollution, erosion, or drought; for changes in albedo or humidity . . . for movements of shoaling fish and migratory creatures.” We can process this data at high speed in our computers; we can communicate it around the world instantly. And we can act on it. “With the power of life in our hands, we could, for instance, make forests spring up on bare lands, safeguard species against the pressures for extinction.” It is time for us, “as incipient planet managers,” to “use this power and use it well,” Myers goes on. “The ancient Greeks, the Renaissance communities, the founders of America, the Victorians, enjoyed no such challenge as this. What a time to be alive!” The physician Lewis Thomas is quoted as saying that if we succeed “we could become a sort of collective mind for the earth.”
This is the defiant reflex, cloaked in a filmy veil of New Age ecological thinking. Many of the proposals of the planet managers are sound—the usual suggestions of environmentalists. In the world we have created, they may offer us our only chance. But the planet managers have respect mostly for man: they understand that the current methods of domination will overheat the planet, but they have new and improved methods. In their forests of the future, cloned Douglas firs and American sycamores will “sprout like mushrooms,” growing straighter, producing “denser wood.” Almost all wildlife can be “harvested” from preserves, so that “conservation and profit can go hand-in-hand.” Even at its most far reaching, though, “macromanagement” remains a fairly crude enterprise. You may be able to keep track of fish by satellite, but they are still wild creatures, growing at their own pace. The next step—the step we stand about to take—is much more radical.
The first time I gave much thought to biotechnology, I was a young reporter covering the weekly meetings of the city council of Cambridge, Massachusetts. For several years, the councillors debated how to regulate the genetic-engineering work then under way at Harvard and M.I.T. Week after week, Nobel Prize winners and brilliant young researchers would arrive at the meetings to answer questions; their biggest doubter was Alfred E. Vellucci, the councillor from Italian and Portuguese East Cambridge, who would long ago have won a Nobel himself if only they were awarded for local politics. Gifted with a strong imagination, Vellucci conjured up countless possible ways for “these bugs,” the reprogrammed organisms, to be accidentally released. Could they escape through the sewers? The air-conditioning? On the soles of people’s shoes? Eventually, and over the protests of the universities, the city enacted fairly strict regulations governing “containment”—the thickness of laboratory doors, and so on. I remember thinking that gene-splicing was something like nuclear power—potentially useful, albeit risky. It didn’t occur to me then to think much more deeply about it.
But genetic engineering is the first way to create new life. It is a staggering idea—“the second big bang,” as one biologist put it. Just in time—just as the clouds of carbon dioxide threaten to heat the atmosphere—we are figuring out a new method of domination, a method more thorough, and therefore more promising, than burning coal and oil and natural gas. It is the method that offers us the most hope of continuing our way of life, our economic growth. It promises crops that need little water and can survive the heat; it promises cures for the new ailments we are creating as well as the old ones we have yet to defeat; it promises a way to survive in almost any environment we may create.
And for this reason it is without a doubt the most important scientific advance ever, in conceptual and moral terms. When I say “moral,” I am not thinking primarily of the uses to which such technology might be put—eugenics, for instance. I am thinking of the very fact of technology. The environmental lobbyist Jeremy Rifkin, who has emerged as one of the few vigorous opponents of genetic engineering, says that for thousands of years human beings have lived “pyrotechnically,” burning, melting, mixing inanimate materials—coal, say, or iron. We have worked from the outside in, to alter our environment. Now we are starting to work from the inside out, and that changes everything. Everything except the driving force, the endless desire to master our planet. The British writer Brian Stableford declares in his celebratory book “Future Man” that genetic engineering “will eventually enable us to turn the working of all living things on earth—the entire biosphere—to the particular advantage of our own species.” No clearer and crisper definition exists of what I have been calling “defiance.”
Watson and Crick described the double helix of DNA in 1953. Just twenty years later, Stanley Cohen, of Stanford, and Herbert Boyer, of the University of California at San Francisco, took two unrelated organisms and cut out a piece of DNA from each. They knit the pieces together, and when they were done they had a new form of life, a kind of life that had not existed five minutes before. In 1981, scientists from the University of Ohio and from Jackson Laboratory, in Bar Harbor, Maine, transferred a gene that controlled the manufacture of part of the hemoglobin in rabbits to a mouse embryo, which they brought to term. The mouse was not exactly a mouse; it had a functioning rabbit gene, which it passed on to subsequent generations. This proof of the possibility of blends between unrelated species was soon followed by others. English researchers crossed a goat and a sheep, two animals that wouldn’t dream of mating in the barnyard (or, if they did—for dreams are widespread—nothing would come of it). At the University of Pennsylvania, biologists managed to insert human growth-hormone genes in the fetus of a mouse. After it was born, the mouse grew twice as fast as other mice and to twice their size. Having passed the gene on to its offspring, it made forever moot the question “Are you a man or a mouse?” These mice are both, and neither.
By the end of 1988, according to a tally in the Times, there were more than a thousand different strains of such “transgenic” mice, as well as twelve breeds of pig and several varieties of rabbits and fish. In the spring of that year, two Harvard researchers announced the creation of a mouse that was genetically altered to develop cancer, so that oncologists could use it for studying new treatments. Unlike the earlier inventions, this mouse had commercial possibilities and was awarded the nation’s first animal patent. The patent was licensed to Du Pont, and the mice will go on sale this fall, for fifty dollars apiece.
Even these mice, though, will be confined to laboratories (until they escape). A bigger barrier probably fell in April of 1987, when workers from a company called Advanced Genetic Sciences released the first genetically altered bacteria to the great outdoors—in a strawberry field in Brentwood, California. Trademarked Frostban, the bacteria—Pseudomonas syringae and Pseudomonas fluorescens—lacked an “ice-nucleating gene” in their DNA and were designed to prevent crop losses from frost damage. Environmental activists had ripped up many of the strawberry plants in an attempt to delay the test, but it was an empty gesture. A few days later, Steven Lindow, the man who discovered the operative gene, sprayed Frostban bacteria on a field of potato plants in Tule Lake, California, without any interference.
The pace of this revolution keeps speeding up. Genetically “improved” trees, for instance, already exist. A Seattle company selects “élite” redwoods from its wild stands, on the basis of such qualities as trunk straightness, height, “specific gravity” of the wood, and “proper branch drop.” Then it clones the trees and plants the seedlings; eventually, gnarly, crooked trees will be gone from its stands. Classical methods of improving seeds do not “adequately satisfy the criteria of the rapid availability of trees of superior quality,” according to a 1982 report by Congress’s Office of Technology Assessment. Christmas-tree growers are now attempting to clone trees with branches that rise at the proper forty-five-degree angle and carry thick needles that “do not fall off to litter the living room floor.” A company called Calgene has isolated a gene that gives tobacco plants some resistance to the herbicide glyphosate. The herbicide works by blocking a pathway in plants that synthesizes aromatic amino acids; once the tobacco plants have been genetically retuned, however, you can spray the herbicide on the surrounding weeds without hurting the tobacco.
The future—the fairly near future—holds much more, at least according to the most fanciful accounts. In his book, Brian Stableford promises that the “battery chickens” of tomorrow will look very different from the birds of the moment, and in fact the accompanying illustration shows them looking rather like hunks of flesh. This is because we may be able to design chickens without the unnecessary heads, wings, and tails. “Nutrients would be pumped in and wastes pumped out through tubes connected to the body,” Stableford says. Perhaps we could “grow” lamb chops on an “infinite production line, with red meat and fat attached to an ever-elongating spine of bone.” Eventually, all plants might “become unnecessary,” having been replaced by artificial leaves that would waste none of the sunlight they received on such luxuries as roots but instead would employ “the energy they trap to make things for us to use.”
And then there’s us. What about night vision, or sonar (although, Stableford says, “this would involve whole new anatomical structures being added to the head”), or double-glazed eyes for living in space, or the “very minor modification” that would allow us to digest cellulose? These developments, though in the future (and farther in the future, I would guess, than these authors predict), are not conceptually different from what we have begun to do in the last twenty years, and what we have started to do in a large way in the last two years. The line is not in the distance; the line is here and now, and we shall very soon be on the other side, if we’re not there already. And on the other side of the line is the second end of nature.
Some people tend not to worry very much about genetic engineering or other such developments, because they think of them as extensions of traditional practices-selective breeding, for example. But nature put definite limits on such activities. Mendel could cross two peas, but he couldn’t cross a pea with a pine, much less with a pig, much less with a person. We could pen up chickens in batteries, but they still had heads. Our understanding of the natural limits helped define nature in our minds. Such notions will quickly become quaint. The idea that nature—that anything—could be defined will soon be outdated. Because anything can be changed. A rabbit may be a rabbit for the moment, but tomorrow “rabbit” will have no meaning. “Rabbit” will be a few strands of genetic code, no more important than a set of plans for a 1940 Ford. Why not make a rabbit more like a dog, or a duck? Whatever suits us. In such a world, nothing will be impossible—including, perhaps, immortality. Why die? (Why age?) Whether eternal life will have any meaning is another matter. “Eventually,” Stableford says, “there may well be a complete breakdown in the distinction between the living and the non-living: the boundary between the two will be blurred and filled in by systems which involve both the machinery of life and the machinery of metal, plastic, and glass.”
All this is speculation, certainly. No one can say with any exactness what will result from a development as awesome as the cracking of the gene. But if that technology falters some other m.ay emerge. It is the logical outcome of our belief that we must forever dominate the world to our advantage. The problem, in other words, is not simply that burning oil releases carbon dioxide, which happens, by virtue of its molecular structure, to trap the sun’s heat. The problem is that nature, the independent force that has surrounded us since our earliest days, cannot coexist with our numbers and our habits. We may well be able to create a world that can support our numbers and our habits, but it will be an artificial world—a space station.
Or, just possibly, we could change our habits.
One very small example of an idea so large as to be unwieldy: To cope with the greenhouse world, people in the developed countries will probably begin to install much more energy efficient washing machines. That would reduce somewhat the amount of carbon dioxide each of us puffs into the atmosphere. But what if, instead, people got together with their neighbors and agreed to buy a single washing machine for the entire block (not such a novel concept to people in big-city apartment houses)? And what if they also decided that instead of continually buying fashionable clothes they would reduce their wardrobes to a comfortable, or even uncomfortable, minimum? What if, in other words, we began to reject a pervasive individual consumerism, and began to alter a basic way we look at ourselves? Mightn’t such a path, broadened to include other facets of daily life, offer the best way not only to avoid overheating the planet but also to keep from transforming it in the other sad ways I have discussed?
As long as the desire for endless material advancement drives us, there is no way to set limits. We are unlikely to develop genetic engineering to eradicate disease and then not use it to manufacture perfectly efficient chickens; there is nothing in the logic of our beliefs that would lead us to draw that line. If there is one item that virtually all successful politicians on earth—socialist and fascist and capitalist—agree on, it is that “economic growth” is good, necessary, the proper end of organized human activity.
Our present environmental troubles, though, just might give us the chance to change the way we think. Spurred by the realization of what we have done, we might begin to think and then behave more humbly. As the effects of man’s domination have become clearer in recent years, a new idea has begun to spread, both in America and abroad. Some environmentalists have begun to talk of two approaches to the world: the traditional anthropocentric view, and the biocentric vision of mankind as just another part of the world. This concept is foreign to most of us. My first sense of what it might mean came a couple of summers ago in Idaho, when I was camped next to a man who hikes almost every year from Mexico to Canada. A dozen times, he told me, he had met grizzly bears, the grandest mammals left on the continent: “The last one, he stood on his hind legs, clicked his jaws, woofed three times. I was too close to him, and he was just letting me know. Another one, he circled me about forty feet away and wouldn’t look me in the eye. When you get that close, you realize you’re part of the food chain.”
The idea that man doesn’t necessarily belong at the top—that the hierarchy we’ve spent many thousands of years establishing is dangerous to other species and also to ourselves—is a strange and powerful idea. The few philosophers and environmentalists interested in such a Copernican shift have taken to calling this alternative path “deep ecology”—as opposed to the “shallow ecology” of conventional environmentalism, which seeks merely to turn mankind into better stewards. Deep ecology suggests that instead of just giving better orders we learn to give fewer and fewer orders—to sink back into the natural world. Deep ecologists question the industrial basis of our civilization, the need to forever grow in wealth and numbers, the entire way we live. We should, they say, work toward a smaller world population—half the current one, maybe, or even less. And we should lay aside our desire for material advancement in favor of “doing with enough.”
Such ideas are not blueprints; they aren’t even outlines. But they are at least a starting point for those who seek to save a world fast vanishing. They are radical ideas, but we live at a radical moment. We live at the end of nature, the instant when the essential character of the world is changing. If our way of life is ending nature, it is not radical to talk about transforming our way of life. When I climb the hill out back, I often pause on a ledge from which I can see my house—the car in the driveway, the chimney above the stove. I love the life that that house represents, love it very much. But I love the hemlocks around me on the hill, too, and the coyotes, and the deer. And it seems that either that life down there must change or the life up here around me will change—the trees will wilt in the sun or else sprout in perfect, heat-tolerant, genetically improved rows.
Exactly what a humbler world would look like I cannot say. We are used to planning utopias, worlds engineered for human happiness. But this would be something different—an “atopia,” perhaps, where the integrity of the planet, and not our desires, would be the engine. If our thinking changed, the details would follow of their own accord. Perhaps we might all begin to use the “appropriate technology” of “sustainable development” which we urge on Third World peasants—solar cookstoves, or bicycle powered pumps. Probably many more of us would be growing our own food. Such solutions are not beyond our imagination. When we decided that accumulation and growth were our economic ideals, we invented wills and lending at interest and puritanism and supersonic aircraft. Why would we come up with ideas less powerful in an all-out race to do with less? The difficulty in accomplishing this transformation is almost certainly more psychological than intellectual—less that we can’t figure out major alterations in our way of life than that we don’t want to. The people whose lives may point the way—Thoreau, say, or Gandhi—we dismiss as exceptional, a polite way of saying that there is no reason we should be expected to go where they pointed. The challenge they presented with the example of their lives is much more subversive than anything they wrote or said, for if they could live that simply it’s no use saying we couldn’t. And maybe now we should—not just for moral or aesthetic reasons but for reasons of chemistry and physics.
Such a change would obviously be colossally difficult. For one thing, while we as individuals would have to change our habits, it would mean very little—save as a good gesture—for any one of us to, say, drive less. Most people have to be persuaded to drive less, and persuaded quickly; this is the first environmental crisis one can’t escape by heading for the woods. It’s also difficult for us to turn our backs on the idea of economic growth, because it has been sold as the answer to the poverty that afflicts most of the planet. For example, S. Fred Singer, the greenhouse skeptic, writes, “Drastically limiting the emission of carbon dioxide means cutting deeply into global energy use. But limiting economic growth condemns the poor, especially in the Third World, to continued poverty, if not outright starvation.” I am sometimes dubious about the actual depth of feeling for the Third World such arguments imply; they mesh too conveniently with our desires. An overheated, ozone-depleted world would probably be crueller to the poor than to the rich, and if our desire is to alleviate poverty, limiting our standard of living and sharing our surplus would likely work as well. But I have no doubt about the power of arguments like Singer’s to stall effective action of any sort if we are reluctant to take such action in the first place.
Still, problems like the inertia of affluence, the push of poverty, and the soaring population are traditional problems. We can think about them, deal with them, perhaps overcome them. In my lifetime, in this country, we have gone from Jim Crow to affirmative action, and there is no saying we can’t do something similar with regard to the planet.
I fear that we won’t, though, and for an entirely different set of reasons—reasons intimately linked to the unique and depressing moment in which we find ourselves. As we have seen, nature is already ending. And not only does its passing prevent us from returning to the world we previously knew but also, for a couple of powerful reasons, it makes any of the fundamental changes I’ve discussed even more unlikely than they might be in easier times.
In the first place, the end of nature is a plunge into the unknown, fearful as much because it is unknown as because the world may become hot or dry or whipped by hurricanes. But the type of shift in attitudes I’ve been describing—the deep-ecology alternative, for instance—would make life even more unpredictable. One would have to begin to forgo the traditional methods of securing one’s future—children, possessions, and so on. As the familiar world around us starts to change, every threatened instinct will have us scrambling to preserve at least our familiar style of life. We can—we may well—make the adjustments necessary for our survival. For instance, some of the early work in agricultural biotechnology has focussed on inventing plants able to survive heat and drought. It seems the sensible thing to do—the way to keep life as “normal” as possible in the face of change. It leads, though, as I have said, to the second end of nature: the imposition of our artificial world in place of the broken natural one.
I got a glimpse of this particular future a few years ago, when I spent some time along the La Grande River in sub-Arctic Quebec. It is barren land but beautiful—a taiga of tiny ponds and hummocks stretching to the horizon, carpeted in light-green caribou moss. There are trees—almost all black spruce, and all spindly, sparse. No one lived there save a small number of Indians and Eskimos—about the number the area could support. A decade or so ago, Hydro-Québec, the provincial utility, decided to exploit the power of the La Grande by building three huge dams along a three-hundred-and-fifty-mile stretch of the river. The largest is the size of fifty-four thousand two-story houses, a Hydro-Québec spokesman told me. Its spillway could carry the combined flow of all the rivers of Europe. Erecting it was a Bunyanesque task: eighteen thousand men carved the roads north through the taiga and poured the concrete. (Photographs show the cooks stirring spaghetti sauce with canoe paddles.) This is the perfect example of “environmentally sound” energy generation; the dams produce a tremendous amount of power without giving off any greenhouse gas. They are the sort of structure we will be clamoring to build as the warming progresses.
But environmentally sound is not the same as natural. The dams have altered an area larger than Switzerland. The flow of the Caniapiscau River has been partly reversed to provide more water for the turbines. In September of 1984, at least ten thousand caribou drowned trying to cross the river during their annual migration. They were crossing at their usual spot, but the river was not its usual size; it was so swollen that many of the animals were swept forty five miles downstream. Every good argument—the argument that fossil fuels cause the greenhouse effect, the argument that in a drier, hotter world we will need more water, the argument that as our margin of security dwindles we must act to restore it—will lead us to more La Grande projects, more dams on the Colorado, more “management.” Every argument that the warmer weather and increased ultraviolet are killing plants and causing cancer win have us looking to genetic engineering for salvation. And with each such step we will move farther from nature.
And as that happens the counter argument—the argument for nature—will grow ever fainter. Wendell Berry once argued that in the absence of a “fascination” with the wonder of the natural world “the energy needed for its preservation will never be developed”—that “there must be a mystique of the rain if we are ever to restore the purity of the rainfall.” This makes sense when the problem is transitory—sulfur dioxide emissions drifting over the Adirondacks. But how can there be a mystique of the rain, now that every drop—even the drops that fall as snow on the Arctic, even the drops that fall deep in the remaining forest primeval—bears the permanent stamp of man? Having lost its separateness, nature loses its special power. Instead of being a category like God—something beyond our control—it is now a category like the defense budget or the minimum wage, a problem we must work out. This alone changes its meaning completely, and changes our reaction to it. The end of nature probably also makes us reluctant to attach ourselves to its remnants, for the same reason that we usually don’t choose new friends from among the terminally ill. I love the mountain outside my back door—the stream that runs along its flank, and the stream that slides down a quartermile mossy chute, and the place where the slope flattens into an open plain of birch and oak. But I know that in some way I resist getting to know it better—for fear, weak-kneed as it sounds, of getting hurt. I fear that if I knew as well as a forester what sick trees look like I would see them everywhere. I find now that I like the woods best in winter, when it is harder to tell what might be dying, but I try not to love even winter too much, because of the January perhaps not so distant when the snow will fall as warm rain. There is no future in loving nature.
And there may not even be much past. Though Thoreau’s writings grew in value and importance the closer we drew to the end of nature, the time fast approaches when he will be inexplicable, his notions less comprehensible to future men than cave paintings are to us. Thoreau writes of the land around Katahdin that it “was vast, Titanic, and such as man never inhabits. Some part of the beholder, even some vital part, seems to escape through the loose grating of his ribs. . . . Nature has got him at a disadvantage, caught him alone, and pilfers him of some of his divine faculty. She does not smile on him as in the plains. She seems to say sternly, Why came ye here before your time. This ground is not prepared for you.” That sentiment describes perfectly the last stage of the relationship of man to nature; though we had subdued her in the low places, the peaks, the poles, the jungles still rang with her pure message. But what will this passage mean in the years to come, when Katahdin, the “cloud factory,” is ringed by clouds that are the work of man? When the great pines around its base have been genetically improved for straightness of trunk and “proper branch drop,” or, more likely, have sprung from the cones of genetically improved trees that began a few miles and a few generations distant on some timber plantation? When the moose that ambles by is part of a herd whose rancher is committed to the enlightened notion that “conservation and profit can go hand-in-hand”? Soon Thoreau will make no sense. And when that happens the end of nature, which began with our alteration of the atmosphere and continued with the responses of the planetary managers and the genetic engineers, will be final. The loss of memory will be the eternal loss of meaning.
I understand perfectly well that defiance may bring prosperity, and a sort of security—that more hydropower will mean less carbon dioxide, and that genetic engineering will help the sick, and that much progress can still be made against human misery. And I have no plans to live in a cave, or even in an unheated cabin. If it took twelve thousand years to get where we are, it will take a few generations to climb back down. But this could be the epoch in which people decide at least to go no farther along the path we have been following—when we make not only the necessary technological adjustments to preserve the world from overheating but also the necessary mental adjustments to insure that we will never again put our good ahead of everything else’s. This is the path I choose, for it offers at least a shred of hope for a living, eternal, meaningful world.
As birds have flight, our special gift is reason. Part of that reason drives the intelligence that allows us to master DNA or build big power plants. But our reason could also keep us from following blindly the biological imperatives toward endless growth in numbers and territory. Our reason allows us to conceive of our species as a species, and to recognize the danger that our growth poses to it, and to feel something for the other species we threaten. Should we so choose, we could exercise our reason to do what no other animal can do: we could limit ourselves voluntarily, choose to remain God’s creatures instead of making ourselves gods. What a towering achievement that would be, so much more impressive than the largest dam—beavers can build dams—because so much harder. Such restraint, not genetic engineering or planetary management, is the real challenge. If we now, today, began to limit our numbers and our desires and our ambitions, perhaps nature could someday resume its independent working. Perhaps the temperature could someday adjust itself down to its own setting, and the rain fall of its own accord. ♦
