Learning the Lessons of a Dying Earth: Future’s Now

Nature, we believe, takes forever, moving with infinite slowness through the many periods of its history, whose names we dimly recall from high school biology--the Devonian, the Triassic, the Cretaceous, the Pleistocene. Ever since Darwin, nature writers have taken pains to stress the incomprehensible length of this path.

We have been told that man’s tenure is as a minute to the Earth’s day, but it is that vast day which has lodged in our minds. The age of the trilobites began some 600 million years ago. The dinosaurs lived for nearly 140 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 mistaken.

Our reassuring sense of a timeless 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. Events, enormous events, can happen quickly. We’ve known this to be true since Hiroshima, of course, but I don’t mean that quickly. I mean that over a year or a decade or a lifetime big and impersonal and dramatic changes can take place. We’re now comfortable with the bizarre idea that continents can die in an atomic second; even so, normal time seems to us immune from such huge changes. It isn’t, though.

In the past three decades, for example, the amount of carbon dioxide in the atmosphere has increased more than 10%, from about 315 to about 350 parts per million. In the past decade, an immense “hole” in the ozone layer has opened above the South Pole. In the past half-decade, the percentage of West German forests damaged by acid rain has risen from less than 10% to more than 50%. According to the Worldwatch Institute, in 1988--for perhaps the first time since that starved Pilgrim winter at Plymouth--America ate more food than it grew.

In much the same comforting way that we think of time as imponderably long, we consider the Earth to be inconceivably large. From my house to the post office at the end of the road is a trip of 6 1/2 miles. On a bicycle, it takes about 25 minutes, in a car eight or nine. I’ve walked it in an hour and a half.

If you turned that trip on its end, the 25-minute pedal past Bateman’s sand pit and the graveyard and the waterfall and Allen Hill would take me a mile beyond the height of Mt. Everest, past the point where the air is too thin to breathe without artificial assistance. Into that tight space, and the layer of ozone just above it, is 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 same case I made with regard to time. The world is not so large as we intuitively believe. Space can be as short as time. For instance, the average American car driven the average American distance--10,000 miles--in an average American year releases its own weight in carbon into the atmosphere. Imagine each 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, some comparatively minor misunderstandings distort our sense of the world. Consider the American failure to convert to the metric system.

As a result, if I read that there will be an 0.8 degree Celsius rise in the temperature between now and the year 2000, it sounds less ominous than a degree-and-a-half Fahrenheit. Similarly, a 90-centimeter rise in sea levels sounds less ominous until one stops to think that over a beach with a normal slope such a rise would bring the ocean 90 meters (that’s 295 feet) above its current tide line. In somewhat the same way, the logarithmic scale that we use to determine the overall composition of our soils or waters--pH--distorts reality like a fun-house mirror for anyone who doesn’t use it on a daily basis.

For instance, normal rainwater has a pH of 5.6. But the acidified rain that falls on Buck Hill behind my house has a pH between 4.6 and 4.2--that is, it is 10 to 40 times as acid as normal.

Of all such quirks, though, the most ephemeral may be the most significant. It 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 though it were on the other side of a great body of water.

If someone says to me that a very bad thing will happen in 2010, I may feign concern but subconsciously file it away. So it always shocks me when I realize that 2010 is almost as close as 1970--closer than the breakup of the Beatles--and that the turn of the century is no further 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 for us to see the future.

Our comforting sense of the permanence of our natural world, our confidence that it will change gradually and imperceptibly if at all, is, then, the result of a subtly warped perspective. Changes that can affect us can happen in our lifetime in our world--not just changes like wars but bigger and more sweeping events. I believe that without recognizing it we have already stepped over the threshold of such a change: that we are at the end of nature. Not that it could happen, but that it has.

By the end of nature, I do not mean the end of the world. The rain will still fall and the sun shine, though differently than before. When I say “nature,” I mean a certain set of human ideas about the world and our place in it. But the death of those ideas begins with concrete changes in the reality around us, changes that scientists can measure and enumerate. More and more frequently, these changes will clash with our perceptions, until, finally, our sense of nature as eternal and separate is washed away, and we will see all too clearly what we have done.

Over the Earth’s history, great amounts of carbon dioxide have been chemically transformed into calcium carbonate, magnesium carbonate and organic matter. And almost all of this has been buried in sediments deep beneath the sea. There is about 100,000 times as much carbon dioxide buried beneath the ocean as in the atmosphere. When we drill into an oil field, we tap into a vast reservoir of this organic matter. We unbury it. When we burn that oil (or coal or natural gas) we release its carbon into the atmosphere in the form of carbon dioxide. This is not pollution in the normal sense of the word.

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 on a Model T. It will emit about 5.6 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 fires have released a substantial amount of the carbon that has been buried over time. It is as if someone had scrimped and saved his entire life, and then spent every cent on one fantastic week’s debauch.

We are living on our capital, as we began to realize during the gas crises of the 1970s. But it is more than waste, more than a binge. We are spending that capital in such a way as to alter the atmosphere. It is like taking that week’s fling and, in the process, contracting a horrid disease.

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 sunlight to warm the Earth. If there were no carbon dioxide, our world might resemble Mars. It would probably be so cold as to be lifeless. A little bit of greenhouse is a good thing, then--the plant that is life thrives in its warmth. The question is: How much?

On Venus, the atmosphere is 97% carbon dioxide. As a result, it traps infrared radiation a hundred times more efficiently than the Earth’s atmosphere, and keeps the planet a toasty 700 degrees warmer than the Earth. The Earth’s atmosphere is mostly nitrogen and oxygen; there’s currently only about .035% to .055% or .06%, which is not very much. But plenty, it turns out, to make everything different.

Carbon dioxide at a very low level largely determines the climate; carbon dioxide at double that very low level, even if it’s still small in absolute terms, could have enormous effect. It’s like misreading a recipe and baking bread for two hours instead of one: It matters.

The world’s population has more than tripled in this century, and, according to United Nations statistics released in May, 1989, is expected to double and perhaps nearly triple again before reaching a plateau in the next century. And the tripled population has not contented itself with using only three times the resources. In the past century, industrial production has grown fifty-fold. Four-fifths of that growth has come since 1950, and almost all of it, of course, has been based on fossil fuels. And in the next half century, the United Nations predicts, this $13 trillion economy will grow another five to 10 times larger.

These physical facts are almost as stubborn as the chemistry of infrared absorption. They mean that the world will use more energy--between 2% and 3% more each year by most estimates. And the largest increases may come in the use of coal.

That is bad news, since coal spews more carbon dioxide into the atmosphere than any other sort of energy (twice as much as natural gas, for instance). China, which has the world’s largest coal reserves and recently surpassed the Soviet Union as the world’s largest coal producer, has plans to almost double her coal consumption by the year 2000.

In other words, this is not something that has been happening for a long time. It is not a marathon or the 24 hours of Le Mans. It’s a 100-yard dash, a drag race, getting faster all the time. If energy use and other contributions to carbon dioxide levels continue to grow exponentially, a model devised by the World Resources Institute predicts that, by about 2040, carbon dioxide levels will have doubled what they were before the Industrial Revolution. If they grow somewhat more slowly, as most estimates predict, the level would double sometime around 2070.

Unfortunately, the solutions are neither obvious nor easy. For example, installing some sort of scrubber on a power-plant smokestack to get rid of the carbon dioxide would seem an obvious fix. But a system that removed 90% of the carbon dioxide would also reduce the effective capacity of the plant 80%.

Because so much of our energy use is for things like automobile fuel, if all the electricity in the United States were generated in nuclear power plants, according to William Moomaw of the World Resources Institute, our carbon dioxide emissions would fall by about 9%. Ditto, at least initially, for cold fusion or hot fusion or any other clean method of producing electricity. So the sacrifices demanded may be on a scale we can’t imagine and won’t like.

(From “The End of Nature,” by Bill McKibben. Copyright, 1989, by William McKibben. Reprinted with the permission of Random House Inc.)

POLLUTING OUR SPACE

“The average American car driven the average American distance--10,000 miles--in an average American year releases its own weight in carbon into the atmosphere. Imagine each car on a busy freeway pumping a ton of carbon into the atmosphere and the sky seems less infinitely blue.”

--”The End of Nature,” by Bill McKibben