The Fate of the Species: Why the Human Race May Cause Its Own Extinction and How We Can Stop It, by Fred Guterl (Bloomsbury USA, 2012)." data-pin-do="buttonBookmark">
The Fate of the Species: Why the Human Race May Cause Its Own Extinction and How We Can Stop It, by Fred Guterl (Bloomsbury USA, 2012). Image: Bloomsbury USA
Adapted from The Fate of the Species: Why the Human Race May Cause Its Own Extinction and How We Can Stop It, by Fred Guterl (Bloomsbury USA, 2012).
The eminent British scientist James Lovelock, back in the 1970s, formulated his theory of Gaia, which held that the Earth was a kind of super organism. It had a self-regulating quality that would keep everything within that narrow band that made life possible. If things got too warm or too cold—if sunlight varied, or volcanoes caused a fall in temperatures, and so forth—Gaia would eventually compensate. This was a comforting notion. It was also wrong, as Lovelock himself later concluded. "I have to tell you, as members of the Earth's family and an intimate part of it, that you and especially civilization are in grave danger," he wrote in the Independent in 2006.
The world has warmed since those heady days of Gaia, and scientists have grown gloomier in their assessment of the state of the world's climate. NASA climate scientist James Hanson has warned of a "Venus effect," in which runaway warming turns Earth into an uninhabitable desert, with a surface temperature high enough to melt lead, sometime in the next few centuries. Even Hanson, though, is beginning to look downright optimistic compared to a new crop of climate scientists, who fret that things could head south as quickly as a handful of years, or even months, if we're particularly unlucky. Ironically, some of them are intellectual offspring of Lovelock, the original optimist gone sour.
The true gloomsters are scientists who look at climate through the lens of "dynamical systems," a mathematics that describes things that tend to change suddenly and are difficult to predict. It is the mathematics of the tipping point—the moment at which a "system" that has been changing slowly and predictably will suddenly "flip." The colloquial example is the straw that breaks that camel's back. Or you can also think of it as a ship that is stable until it tips too far in one direction and then capsizes. In this view, Earth's climate is, or could soon be, ready to capsize, causing sudden, perhaps catastrophic, changes. And once it capsizes, it could be next to impossible to right it again.
The idea that climate behaves like a dynamical system addresses some of the key shortcomings of the conventional view of climate change—the view that looks at the planet as a whole, in terms of averages. A dynamical systems approach, by contrast, consider climate as a sum of many different parts, each with its own properties, all of them interdependent in ways that are hard to predict.
One of the most productive scientists in applying dynamical systems theory to climate is Tim Lenton at the University of East Anglia in England. Lenton is a Lovelockian two generations removed— his mentors were mentored by Lovelock. "We are looking quite hard at past data and observational data that can tell us something," says Lenton. "Classical case studies in which you've seen abrupt changes in climate data. For example, in the Greenland ice-core records, you're seeing climate jump. And the end of the Younger Dryas," about fifteen thousand years ago, "you get a striking climate change." So far, he says, nobody has found a big reason for such an abrupt change in these past events—no meteorite or volcano or other event that is an obvious cause—which suggests that perhaps something about the way these climate shifts occur simply makes them sudden.
Lenton is mainly interested in the future. He has tried to look for things that could possibly change suddenly and drastically even though nothing obvious may trigger them. He's come up with a short list of nine tipping points—nine weather systems, regional in scope, that could make a rapid transition from one state to another.