In 2006 James Lovelock published a book that bluntly laid before us the consequences of the carbon imbalance. The Revenge of Gaia was published in its author's eighty-seventh year, and it is as bleak and penetrating a perspective on human folly in regard to the environment as has ever been written. Lovelock argues that Gaia's climate system is far more sensitive to greenhouse-gas pollution than we imagine, and that the system is already trapped in a vicious circle of positive feedback. "It is almost as if we had lit a fire to keep warm," Lovelock opines, "and failed to notice, as we piled on fuel, that the fire was out of control and the furniture had ignited." Although there is still time to avert a catastrophe, Lovelock believes that humans lack the foresight, wisdom, and political energy required to do so. Instead, he predicts, before the twenty-first century is out our global civilization will have collapsed and a new dark age will have descended on us. Only a few survivors (perhaps just one out of every ten alive today) will cling to the few remaining habitable regions, such as Greenland and the Antarctic Peninsula.
The events likely to destroy our civilization include dramatic rises in sea level, which will flood coastal cities and some of the best agricultural land; changes in rainfall; extreme weather; and the disappearance of the glaciers that act as dams and whose meltwaters provide our most productive agricultural regions with water in the growing season. The ensuing starvation, warfare, and chaos will be the greatest scourge, for in Lovelock's projected dark age the warlords will be armed with nuclear weapons.
How probable is it that this bleak vision will come to pass? Because of new scientific data and technological analysis we are better placed than ever before to determine the scale of the threat and its imminence. Let's begin with a new analysis of work done by the Intergovernmental Panel on Climate Change (IPCC) in 2001. In its Third Assessment Report, the IPCC published a series of projections concerning key indicators of Earth's climate system. These included estimates of how swiftly Earth's average temperatures might increase over the course of the twenty-first century, how much the oceans would rise, and how quickly CO2 would accumulate in the atmosphere. The projections had an upper and a lower limit, and they encompassed quite a wide range of possibilities. The projection concerning temperature, for example, indicated that the increase might be as little as 2.5 degrees Fahrenheit, or as much as 10.4 degrees. From the perspective of human survival, the difference between 2.5 degrees and 10.4 is profound. Humanity can probably cope with a warming of less than 3 degrees, but a 10.4-degree warming would be truly catastrophic, heralding an ice-free world, and most likely human tragedy on the scale envisaged by Lovelock.
At the time these projections were published, skeptics described them as unbelievable and grossly inflated, and widely proclaimed in the popular press that they amounted to scientific scaremongering. By 2007, however, scientists had five to six years' worth of real-world data under their belts, allowing them to revisit the projections to determine their accuracy, at least over the near-term, early portion of the curve. What they discovered should have been reported the front page of every newspaper on the planet. Astonishingly, in every instance the real-world changes were at the upper limit, or worse than even the worst-case scenario presented by the IPCC. The full implications of these new studies have yet to sink in among those negotiating the global treaty that is supposed to protect humanity from dangerous climate change. The negotiators continue to argue on the basis of the old projections, which call for action far less urgent than what is actually required. Worse, the negotiations grind on as if we had an eternity to achieve outcomes. Lovelock, who seemed like just another prophet of doom just two years ago, appears to have been right after all-unless, that is, we can rouse ourselves to take immediate action.
These changes in the Arctic have left many scientists worried that the region is already in the grip of an irreversible transition
From mid-2007 onward I've found it increasingly difficult to read the scientific findings on climate change without despairing. Perhaps the most dispiriting changes are occurring at the north pole. The sea ice that covers the Arctic Ocean is an ancient feature of our planet. It has glistened brightly into space for at least 3 million years, and over that time a host of organisms, from plankton to walruses and narwals, have adapted to life on and under it. But its importance to Gaia is far greater than as a home for an unusual fauna: the northern ice acts as a refrigerator that cools the entire planet. It does this by reflecting the sun's energy away from Earth. During the summer, the sun's rays beat down upon it twenty-four hours a day, but because the ice is bright, 90 percent of that energy (which averages 22 watts per square foot) is deflected back into space. Where the ice is absent, however, the dark ocean is revealed, and it soaks up all that solar energy and turns it into heat.