American Scientist

Field Notes from a Catastrophe: Man, Nature, and Climate Change. Elizabeth Kolbert. x + 210 pp. Bloomsbury, 2006. $22.95.

The Weather Makers: How Man Is Changing the Climate and What It Means for Life on Earth. Tim Flannery. xx + 357 pp. Atlantic Monthly Press, 2005. $24.

If the release of carbon dioxide into the atmosphere from the burning of coal, oil and gas is not reduced greatly and soon, the consequences are likely to be catastrophic. So say Tim Flannery and Elizabeth Kolbert, authors of two new books that provide ample evidence that those emissions are adversely affecting the complex web of interactions that ties Earth's organisms to climate.

The incipient catastrophe is manifesting itself in a myriad of ways. A half-century ago, the Inupiats of the small Alaskan island of Shishmaref were able to venture 20 miles out onto the sea ice to hunt seals; now that ice turns to slush only 10 miles out. Storm surges that were once held at bay by the ice now regularly eat away at the island, a strip of land only a quarter of a mile wide; a single storm can remove as much as 125 feet. Once houses sat square and firm on the frozen ground; now they tilt and veer as the melting soil softens and gives way. The Inupiats recently voted to move their village inland, away from their ancestral home—an early loss to global warming.

This scene from Shishmaref is among those described by Kolbert in Field Notes from a Catastrophe, which is based on a series of articles that appeared last year in the New Yorker. Such is the power of the images she paints that, soon after the series appeared, a senior staffer to a Republican senator told me, "When the Eskimos start moving their villages, you know it's time to start doing something."

Kolbert describes scientists at a research station on the Greenland ice sheet working rapidly in the early morning, trying to avoid the slush and rivers of water that will form later in the day from the melting ice. This water sinks rapidly through cracks in the ice cap to the rocky base, lubricating the flow of the ice to the sea, where icebergs will calve off, raising sea level and flooding coastal communities. When the sea freezes, as ice forms, heavy salty water is pushed out and sinks. When icebergs melt, the cold fresh water they contain spreads across the ocean surface (rather than sinking into the denser, saltier waters below), thereby interfering with the large-scale thermohaline circulation of the ocean. No one can predict with confidence how interference with such planetary-scale processes will affect climate. We are like children poking at a sleeping polar bear, without knowing what will happen when it wakes up.

Kolbert also tells of past civilizations being decimated by relatively tiny fluctuations in climate. The Akkadians, living between the Tigris and Euphrates some 4,300 years ago, were an advanced agricultural people with a written language and a complex system to account for the production and distribution of barley and wheat. Their society was destroyed by a drought that not even the earthworms survived. Other cultures, including the classic Maya of Mesoamerica, met a similar fate as a result of climate changes that pale in significance compared with what is predicted to occur later this century. What do these past casualties forebode for our future?

Kolbert is like Matisse, painting an evocative picture with a few deft strokes. Tim Flannery, in contrast, works more in the style of Seurat, building up a persuasive portrait of a threatened planet, point by scientific point. His book The Weather Makers is an impressively researched, broad-ranging survey of the scientific foundations of climate science. Kolbert constructs her story around the people doing the science; Flannery puts the science itself in the forefront. Kolbert focuses on the effects of climate change that can be observed to be happening now; Flannery sets his sights at a greater distance, discussing climate variation throughout Earth's history and describing the outlook for our future. Kolbert avoids detailed scientific discussion; Flannery tries to communicate enough of the science to allow the reader to develop his or her own understanding. Both books are excellent.

Although the two volumes address nearly the same issues, there is little overlap between them. But Flannery and Kolbert do both tell the story of the golden toad, formerly found in the Monteverde Cloud Forest in central Costa Rica. Discovered in 1964, the toad lived most of its life underground, displaying its bright tangerine color for a brief period when it came to the surface to breed explosively, laying its eggs in puddles. Too much rain, and the eggs would get washed downhill; too little, and the puddles would dry before the tadpoles could turn into toads. In 1987, a biologist counted 1,500 toads. That spring was unusually warm and dry, so the puddles evaporated early. The next year, Kolbert says, only 10 toads were found. The year after that, a single golden toad was seen—the last ever recorded. Kolbert writes, "It is widely assumed that after living its colorful, if secretive, existence for hundreds of thousands of years, Bufo periglenes is now extinct." Cloud forests are expected to largely disappear as our planet becomes hotter. Who knows how many species will disappear without ever having been observed?

Flannery points out that fundamental climate science is not something new: The basis was laid down by experiments and observations made more than a century ago. The Earth is getting hotter than it otherwise might because greenhouse gases, primarily carbon dioxide, are accumulating in our atmosphere.

Today, carbon dioxide is produced primarily by the burning of fossil fuels. Because CO₂ is a greenhouse gas (meaning that it is transparent to visible light but blocks parts of the infrared spectrum at which the Earth radiates its heat energy to space), adding it to the atmosphere results in a heating of the Earth's surface. Flannery skillfully describes climate processes that amplify this warming. For example, the surface heats, causing ice and snow to melt. Sea ice reflects 90 percent of light back out into space, but the ocean absorbs 90 percent of light. So when sea ice melts, the result is further heating of the portion of the ocean's surface that had previously been ice-covered.

Flannery is at his best when describing the complex web of ecological relationships that can be disrupted by rapidly changing climate. In chapters with titles such as "The Unraveling World," "Peril at the Poles" and "The Great Stumpy Reef," he tells us how much of the life on our planet is threatened by global warming. As we see from the golden toad and many other examples Flannery provides, subtle shifts in temperature and precipitation can result in the demise of many individual plants and animals, ultimately leading to the extinction of many species. If global warming continues as projected, species will need to move poleward three or four miles per year on average to avoid overheating. For many species, movement on that scale is simply impossible. For others—for example, those living on islands—natural barriers prevent such migration. For most species, human-erected barriers in the form of roads, farms, towns and cities block the way. Extinction is an abstract concept, difficult to grasp, but it takes the concrete form of the suffering of individual creatures, such as a polar bear falling through thin sea ice and desperately drowning in the frigid brine. (The bears are strong swimmers but are adapted for swimming close to shore; some now have to swim many miles across open sea to find food as the ice floes from which they feed melt, become smaller and drift apart, and drowned carcasses are being found off the north coast of Alaska.)

Climate effects of carbon dioxide are not the only problem. As CO₂ is absorbed by seawater, it makes the water more acidic. If current patterns of coal, oil and gas consumption continue, before the end of this century the ocean will begin to dissolve some of the organisms that live in it—polar pteropods (small marine snails), for example. Another problem is that by that time, the surface-water carbonate mineral saturation state will probably be so low that corals will be unable to calcify. Arguably, our CO₂ emissions represent the greatest threat to life on Earth since a comet wiped out the dinosaurs some 65 million years ago.

Kolbert describes the paralysis of the Bush Administration, which acts as though press releases and sound bites are the primary tools needed to combat this threat. But our energy system is at the root of the problem. There are differences of opinion regarding how tough it would be to provide the energy needed to sustain "the good life" throughout the world without damaging our planet. Flannery contends that minor lifestyle changes such as the adoption of hybrid cars would go a long way toward solving the problem.

This line of argument is supported by Robert Socolow, a Princeton professor who, Kolbert tells us, thinks that we have the technology but not the political will to tackle this problem. Socolow likens our CO₂ emissions to slavery. Eliminating slavery made our cotton more expensive, but we didn't get rid of slavery based on an economic argument; rather, people recognized that slavery was wrong. Similarly, getting rid of CO₂ emissions will be expensive, but it will happen when we recognize that it is morally wrong to emit CO₂ into the atmosphere.

In the United States, the demand to eliminate slavery developed in the North, where mechanized manufacturing allowed the luxury of a refined moral sense. Will we be able similarly to indulge a desire based on ethics? Another subject of Kolbert's book, New York University physics professor Martin Hoffert, hopes so. He argues (like some others) that it will be the development of new energy technologies that will allow us the luxury of a moral sense that leads to the elimination of CO₂ emissions. Hoffert has led the call for a crash program to develop clean energy technologies—perhaps the energy needed for our growing and developing world can be provided by high-altitude wind turbines tapping into the energy of the jet stream, from solar satellites orbiting the Earth or from some other source not yet conceived, he contends.

We evolved as hunter-gatherers, with minds adapted to focus optimally on our immediate surroundings, the present moment and the people to whom we are most closely genetically related. Now we are confronted by a problem that is global in scope, was centuries in the making and is threatening almost every species on the planet. Can our hunter-gatherer minds rise to meet the social, political and technical challenges posed by modern global industrial society? Kolbert quotes Hoffert, who is dubious:

I'm not sure we can solve the problem. I hope we can. I think we have a shot. I mean, it may be that we're not going to solve global warming, the earth is going to become an ecological disaster, and, you know, somebody will visit in a few hundred million years and find there were some intelligent beings who lived here for a while, but they just couldn't handle the transition from being hunter-gatherers to high technology.

I highly recommend both Field Notes from a Catastrophe and The Weather Makers. The former is more poetic, yet it contains a bit of Fortran code. It is balanced and understated, and I did not detect a single error. The Weather Makers is chock-full of interesting facts, but amid them are a few that would have benefited from a little more prepublication review—the book contains a number of small errors, such as equating the thermohaline circulation with the Gulf Stream. Flannery's tone is a bit higher in pitch than Kolbert's, but even if things are only half as bad as he makes out, or if the problem is 10 times harder to solve than he suggests, he does convince us that this problem is worth solving.

These two books can be understood easily by the average reader, yet even most researchers in climate science will learn a lot from them. One might consider consuming Kolbert's slim volume as an appetizer, or a light first course, before sitting down to the heartier fare provided by Flannery. I recommend both works to anyone who has a concern for the fate of our planet.