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CHAPTER 1

NOW or NEVER

IN THE YEAR FOUR BILLION

We succeeded in taking that picture, and if you look at it, you see a dot. That's here. That's home. That's us. On it, everyone you ever heard of, every human being who ever lived, lived out their lives. The aggregate of all our joys and sufferings, thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilizations, every king and peasant, every young couple in love, every hopeful child, every mother and father, every inventor and explorer, every teacher of morals, every corrupt politician, every superstar, every supreme leader, every saint and sinner in the history of our species, lived there on a mote of dust, suspended in a sunbeam.

— CARL SAGAN, 11 May 1996

The image that moved Carl Sagan to such poetic magnificence was taken by Voyager 1 on 14 February 1990. The vessel was 4 billion miles from home — a mile for every year of Earth's existence — when it captured that image, and in it Earth is nothing more than a minute blue dot, all but lost in the immensity of the cosmos. At the time Sagan described our home so beautifully he had just half a trip around the sun — six months — to live; and he well knew that the "mote of dust" that had carried him on his life journey is an extraordinary place, for it is the only living planet we know of in all the vastness of the universe.

With the twenty-first century nearly a decade old, Sagan's description resonates more powerfully than ever. Our despoliation of Earth's life-support systems seems to mark us as the destroyer of our own civilizations; and as the planetary crisis we have created deepens, it is certain that no savior will ride across the cosmos to rescue us from ourselves. There is no real debate about how serious our predicament is: all plausible projections indicate that over the next forty to ninety years humanity will exceed — in all probability by about 100 percent — the capacity of Earth to supply our needs, thereby greatly exacerbating the risk of widespread starvation, or of being overwhelmed by our own pollution. The most credible estimates indicate that we are already exceeding Earth's capacity to support our species (this is called its biocapacity) by about 25 percent. With global food security at an all-time low, and greenhouse gases so choking our atmosphere as to threaten a global climatic catastrophe, the signs of what may come are all around us.

Everyone knows what the solution is: we must begin to live sustainably. But what does that actually mean? "Sustainability" is a word that can mean almost anything to anyone. Whether used by cosmetics advertisers or fruit sellers, it is bandied about as if it were the essence of virtue. Yet so recent is the word that my spell-checker doesn't recognize it.

Wikipedia, which is increasingly taken as a fouret of all knowledge, defines sustainability as "a characteristic of a process or state that can be maintained at a certain level indefinitely." This is hardly a moral definition this, or indeed — in light of the second law of thermodynamics — a feasible one. Many environ-mentalists opt for a more practical meaning: "living in such a way as not to detract from the potential quality of life of future generations." And here we find a definition in harmony with a commonly voiced aspiration: to "try to leave the world a better place than we found it." This essay is in part an inquiry into the causes of our common failure to realize this heartfelt desire — even though it is held by almost every individual on Earth.

If we accept the environmentalists' definition, living sustainably does not involve any particular morality beyond an extension of the Eighth Commandment: Thou shalt not steal — even from future generations. A society that limited itself to such a narrow aspiration, however, could be a barbarous place. As in the movie Soylent Green, why waste a corpse? Why worry about the distribution of wealth? Any meaningful inquiry into sustainability must surely be broader than this, and thus be as much a philosophical and moral discussion as a scientific one; for sustainability pertains to us — our innate needs and desires — as much as it does to the workings and capacities of our planet. A real search for sustainability involves a broad vision — indeed, it encompasses many flash-point issues: Is eating meat appropriate in a sustainable world, for example? And what of animal rights — and human rights — and religion, and democracy, and the free market, and war? Although a detailed consideration of how these issues can be squared with a fully sustainable future is beyond the scope of this essay, such questions will continually arise as we examine clear, practical solutions to our most urgent problems.

Where does science fit into this inquiry? In human affairs there is often a great difference between aspiration and achievement. Even a society that has developed a moral and philosophical framework ideally suited to attaining a sustainable future may fail to accomplish that if it lacks knowledge of how the world works, and of how its own practices and technology are affecting Earth's life-support systems. Accurate scientific knowledge of Earth and its processes is vital to the pursuit of sustainability. And so I begin this investigation with two questions, which, even if they cannot be definitively answered, can nevertheless guide us in our search: What is our purpose as a species? And how does Earth work?

The wellsprings from which we derive meaning in our lives are intensely personal. My own search for meaning has led me to the belief that this generation — the generation living in the early twenty-first century — is destined to achieve an extraordinary transformation, unique in the 4-billion-year history of Earth, and that this transformation will influence the fate of life from now on. Geologists talk of the dawning of a new geological period called the Anthropocene, which is characterized by pervasive human influence on the Earth's processes. But perhaps the Anthropocene age will truly have dawned only when humanity uses its intelligence to help regulate those processes for the good of life as a whole.

The great complexity and order created by evolution through natural selection have led to the concept of Gaia: Earth as a self-regulating, evolving system. James Lovelock, the originator of the Gaia hypothesis, illustrated it by showing how Earth as a whole maintains the temperature of the planet's surface within bounds that are conducive to life, recycles nutrients, and regulates the chemistry of the atmosphere and oceans to the same effect. In short, living things absorb carbon and heavy metals from the atmosphere and oceans, while at the same time producing oxygen. Life is such a powerful force that this activity keeps the atmosphere and oceans out of chemical balance with the rocks in a way that keeps Earth habitable. The Gaia hypothesis is a way of describing how our living planet works as a whole.

We have long understood — from biblical teachings and practical experience — that we are naught but earth: ashes to ashes, dust to dust, as the English burial service puts it. Indeed, "Dust thou art, and unto dust shalt thou return" (Genesis 3:19) are among the oldest written words that have come down to us. Yet although we have long understood that we are earth, it is equally true, but almost never said, that we are Earth (i.e., part of planet Earth) as well. We are Earth by virtue of the fact that every one of us has been shaped by the process of evolution through natural selection: the process that led to the exceedingly complex and highly ordered structures of life and its ecosystems. And this fact has a profound implication: Earth was not made for us; rather, we were made for this Earth.

This implication about our purpose goes against some of the most powerful currents in western civilization, including the Christian tradition I grew up in. In fact, it is diametrically opposed to such currents, for it asserts that we have evolved to serve Earth, and that our great distinguishing characteristic — our intelligence — is not ours alone, but Gaia's as well, for it is destined to be used by Gaia for her own purposes. James Lovelock took the term Gaia from the ancient Greeks: it was the name of their earth goddess. I believe that over the course of the twenty-first century we will again come to serve our Earth goddess, and perhaps even revere her.

Looking at the current condition of Earth, you might be tempted to see humanity as an enemy of Gaia, but to do so would be a mistake. We are obviously part of Gaia, and, just as obviously, as animals in the Gaian system we must kill (even if we kill only vegetable matter) in order to survive. Gaia is all about the giving, taking, and reprocessing of life. Conceiving of ourselves as outside of and antagonistic to Gaia is, I believe, a terrible mistake, for it leads us to consider actions necessary for our survival as somehow wrong. As animals we must eat, and eating implies taking life. Striving for a bloodless, painless world of perfect morality and zero impact on nature is delusional. Even more important, it blinds us to what I believe is the true purpose, according to the Gaian perspective, of our existence.

I believe that the deepest significance of the twenty-first century can be glimpsed in the hierarchical structure of life on Earth. Here lies the potential for sustainability and the transformation of our existence. Guided by evolution, the history of life has been one of increasing complexity and increasing efficiency. The eminent evolutionary biologist Stephen Jay Gould argued that life has not increased in overall complexity, because simple life- forms such as bacteria still constitute by far most of life on Earth. Yet from a Gaian perspective, this theory overlooks the undeniable spread and increasingly sophisticated development of life. Life has spread from its origins on the bottom of shallow seas 3.5 billion years ago to almost all parts of Earth's rind. Some 540 million years ago, creatures learned to burrow into the sediments of the seafloor. Then they colonized land, the air, and the ocean depths. Furthermore, as life evolved and spread, it has improved. The reproductive systems and the use of energy in many evolutionary lineages have become more efficient over time; and in these lineages the brain (the command-and-control system) has grown larger and more sophisticated relative to the brains of ancient ancestors.

Large, highly evolved creatures such as mammals play a disproportionately important role in influencing the carbon cycle and other ecosystem processes. There is no doubt that their evolution has increased Gaia's ability to control planetary life-support systems, for as mammalian metabolism has become more complex and efficient, so has that of the planet as a whole. Six hundred million years ago, when there was little or no complex life on Earth, thermostatic control was so poor that the planet repeatedly froze right to the equator, an event known as "snowball Earth." Since the rise of complex life, such events have not recurred.

Evolution through natural selection is a blind process that takes place only by means of variation (within populations) and failure to reproduce (of the less well adapted). That's why Richard Dawkins likened the process to a "blind watchmaker." But now, after 4 billion years, the evolutionary process has arrived at a potentially powerful and swiftly responsive command-and- control system that may serve Gaia as a whole. That system is our own human intelligence and self-awareness. It is my belief that we humans are poised to become, from now on, the means by which Gaia will regulate at least some of its essential processes.

Is it right to say that we are Gaia's self-awareness? Gaia's brain? I believe it is. After all, we commonly talk about our own self-awareness, yet rarely question whether our toes, for example, are aware of the beautiful starry night that our brain is taking in. Admittedly, the human body is far more highly integrated than are Gaia's disparate parts. But it is undeniable that we are a part of the Gaian whole. Whether there is a Gaian meaning to our existence or not, acknowledging that we are an influential part of Gaia requires a change in the way we interact with Earth's life-support processes. After all, the brain does not despoil the body that it is part of, for to do so would be to destroy itself. Admittedly, the brain is expensive to run. Our own brain, which constitutes just 2 percent of our body by weight, greedily takes about 20 percent of all the energy we consume. As Gaia's intelligence, humanity will doubtless impose a heavy tax on Gaia, yet this burden cannot be so great as to bankrupt the system that supports it.

Gaia's potential for intelligent control is very recent: it arose abruptly toward the end of the twentieth century, after humans had plumbed the depths of the oceans, revealed Earth's internal structure and history, and photographed it from deep space. Scientists such as Carl Sagan were the first to recognize the full significance of these achievements, yet because we have not focused on sustainability, even today the great mass of humanity is unaware of their true import.

By the twenty-first century the achievements of pioneers such as Sagan had opened the way to a limited understanding of how Earth works. Here, scientists such as James Lovelock led the way, and as a result of their efforts we can now describe in some detail how Earth recycles minerals and nutrients, how atmospheric and oceanic chemistry is maintained, how the surface temperature of our planet is regulated, and how biodiversity is protected from external shocks. It is as if, by the late twentieth century, we finally lifted the hood of our planetary vehicle and saw the sophisticated engine concealed within. Then, at the dawn of the new century, we began to understand how it worked.

Such deep understanding of Earth's self-regulatory systems is invariably empowering. Just as surgery could not progress without Harvey's discovery of the circulation of the blood, humanity could not hope to positively influence Earth's thermostat without knowledge of the carbon cycle. If the twentieth century was the century of technological triumph, then the twenty- first century may be an even more significant moment in planetary history: the century when our knowledge of Earth's processes must be put to use. Within the lifetimes of many people reading this essay, after 4 billion years of self-regulation, Gaia will pass from an unconscious to a conscious means of control. Either that or we will fail to achieve sustainability, and Gaia's newly attained consciousness — which is made possible only by our global civilization — will vanish, perhaps to be lost forever.

It is all too possible that we will fail to achieve sustainability, and that the blind watchmaker will once again — through variation of organisms and through the failure of ill-adapted organisms to reproduce — reset the balance of a severely diminished living Earth. Well before we were ready to assume control of the planet, humans were already influencing Earth's processes in ways that threatened to end in global catastrophe. Acting without an awareness of the consequences of our actions, or even a sense of responsibility, we were (from the perspective of Gaia's purpose) immature. Now our fate and that of our planet will be determined by the rate at which we, as a species, can mature and develop a new sense of responsibility. I fear that if we are to avoid catastrophic failure, we will need to learn very fast: learn, indeed, on the job. Our search for sustainability is thus an uncertain experiment, which must inevitably see setbacks and failures. Succeeding at it in the long run will be the greatest challenge our species has ever faced.

THE CLIMATE PROBLEM

There was a time, about 100,000 years ago, when there were just 10,000 people on Earth. A century ago there were 1.5 billion of us, and now there are 6.6 billion. It is estimated that just forty years from now there will be 9 billion. With luck and good management, our population will not grow beyond this point. But some estimates see the number swelling by 1 billion or more in the century after that. That's 10 billion people, on a planet that once held 10,000. Such a burden of human flesh, which all needs to be housed, clothed, and fed, will exacerbate all our environmental woes. Yet who can we ask to get off? The truth is that if we wish to act morally, we can influence population numbers only slowly. So, although it's important to focus on decreasing the population as a long-term solution, we cannot look to it as a solution to the immediate crises.

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Excerpted from "Now or Never"
by .
Copyright © 2009 Tim Flannery.
Excerpted by permission of Grove Atlantic, Inc..
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