Late this year, if all goes as planned, a 90-year-old James Lovelock will rocket into suborbital space as Virgin Galactic's premier spaceflight tourist. It's a two-hour-plus trip that includes several minutes of weightlessness, during which Lovelock will be able to take an affectionate look at his first love, Gaia -- our blue planet. Lovelock, a British scientist without portfolio but with many admirers, is a friend of Virgin's gleaming entrepreneur, Richard Branson, who enlisted him as a judge in the Virgin Group's $25-million challenge to devise a way to reduce atmospheric greenhouse gases to an acceptable level. Lovelock does not really think this is possible. There are too many of us -- closing on 7 billion at last count.
"It is not simply too much carbon dioxide in the air . . . ," he writes in "The Vanishing Face of Gaia," "the root cause is too many people, their pets, and their livestock -- more than the Earth can carry. No voluntary human act can reduce our numbers fast enough even to slow climate change." Just the breathing those billions of people do, he writes, "is a potent source of carbon dioxide. . . . Like it or not, we are the problem." Because of our numbers and our depredations, the Earth is in a state of positive feedback: "deviations of the climate are amplified, not suppressed, so that greater heat leads to even greater heat."
Earth's atmosphere is "entirely the product of living organisms at the surface." This is a central tenet of Lovelock's Gaia hypothesis, which he conceived in the 1960s, as the environmental movement booted up and the New Age arrived. Because of that unfortunate timing, his hypothesis had for a long time a tie-dyed aura. Gaia, he recalls, was "the science that dare not speak its name." (The name, that of the Greek goddess of the Earth, was suggested to him by his neighbor, novelist William Golding.)
Today it has become a respectable discipline and is called Earth system science by geophysicists and geochemists who can't bring themselves to call it Gaia theory. But it is Lovelock's science -- a study of Earth's physiological responses to its biota. Lovelock has contributed to its respectability by speaking of Earth now as "self-regulating" rather than, as he originally put it, "alive." He still calls it Gaia theory, though ("[W]ould you have read this book if it had the title "The Vanishing Face of Earth System Science"?)
Lovelock insists that "the goal of [Earth's] self-regulation is the maintenance of habitability." One of the theory's early predictions was that no life would be found on Mars, since spectrographs showed that its atmosphere is in chemical equilibrium; that is, nothing goes on in the air, so nothing is going on on the ground. So far, this is how it looks. Conversely, Earth's atmosphere is "profoundly at disequilibrium," yet analysis of ice cores and sediment indicates that the amount of oxygen has been close to the optimal (for Earth life) value of 21% for 200 million years. This and other unstable atmospheric abundances are "wholly inexplicable by inorganic processes alone." In 2006, the rehabilitated Lovelock was awarded the Wollaston Medal by the Geological Society of London.
Lovelock is a plain and simple writer, and his prose has a natural grace that makes this book a pleasure to read despite its depressing thesis. He considers the reports of the U.N.'s Intergovernmental Panel on Climate Change too optimistic, constrained by "consensus" (a word that makes his teeth itch) and wedded to computer models. A chapter on geoengineering lists ways to slow global heating, such as placing a sunshade in solar orbit synchronous with Earth, and notes that volcanic eruptions suggest that injecting sulfur compounds into the stratosphere temporarily halts atmospheric warming and will buy us time.
But that time, he argues, should be spent not in frantic attempts at geoengineering or even in planting trees, installing wind farms or pursuing other Lilliputian "green" endeavors but in "adaptation" to Earth's inevitable jump to a new hot, stable state. "Simply cutting back fossil-fuel burning, energy use, and the destruction of natural forests will not be a sufficient answer to global heating," he writes, "not least because it seems that climate change can happen faster than we can respond to it. . . . Because of the rapidity of the Earth's change, we will need to respond more like the inhabitants of a city threatened by a flood. When they see the unstoppable rise of water, their only option is to escape to higher ground."
The human species (but not the whole population) will survive in habitable pockets near the poles, and those who can had best start moving there. "Are we sufficiently talented to take on what might become the onerous permanent task of keeping the Earth in homeostasis?" Lovelock asks. "The alternative is the acceptance of a massive natural cull of humanity and a return to an Earth that freely regulates itself."
Here is where those who have faith in the sufficiency of human talent may wish to part company with Lovelock. He believes that "the welfare of Gaia is more important than the welfare of humankind." To some, this will seem like putting the cart before the horse. He gives lip service to the importance of preserving our DNA, but you sense that his heart isn't in it. Soon he'll be more than 60 miles above the Earth -- and that may be his true territory. From there, you can't see the Earthlings.
Lippincott is a freelance editor specializing in science.