Book Review: Under a Green Sky
Read this book only if you really, really like rocks.
Okay, that’s not quite fair. It’s not that the subject matter doesn’t interest me—quite the contrary, actually, considering my lifelong obsession with paleontology—but Peter D. Ward’s thesis would have far better digested if it had been condensed into a magazine feature, so you’re not forced to trudge alongside him as he polishes off every ammonite and trilobite, or squints at every petrified sedimentary strata, while all you want is for him to hurry up and get to the point, already. And though eloquent, he’s not a terribly engaging writer, and his attempts to come off as more personable are obtrusive and trite.
But if you do like rocks? Boy, have I got a book for you.
It’s widely accepted today that the dinosaurs were wiped out 65 million years ago by an asteroid hurtling towards the Earth. (Though my favorite crackpot theory is that the rise of angiosperms, or flowering plants, resulted in some fairly explosive—and deadly—allergies.) Ward brings us back even further—250 million years ago, at the end of the Permian period, to be exact—when something decimated almost 95 percent of the earth’s species. Many possible reasons have been suggested: another impact from space, volcanic activity, or melting methane ice in sea sediments—all of which could have gradually or dramatically altered the earth’s atmosphere by throwing up large amounts of greenhouse gases into the air, and resulting in a slow warming up of the planet’s surface.
Tracking this train of thought, Ward asserts that whatever the instigator, the Permian extinction, along with at least three other recognized mass-extinction events, were brought on by climate change.
This isn’t a new theory, nor is it a huge mental leap, considering that most biologists concur that we’re in the middle of the sixth mass extinction—one that could possibly outrival the past five. The number of species going extinct increases with every tiny spike in temperature, snowballing into what some scientists are calling a “highway to extinction.” A 2004 paper, published in Nature, concluded that 15 to 37 percent of all the species in the six regions studied could be driven to the great wildlife reserve in the sky between now and 2050. Extrapolated globally, this means that more than a million species could be headed for oblivion. And this is in a middle-of-the-road climate-warming scenario. Cutting greenhouse-gas emissions now, the researchers say, could save many species from disappearing.
Ward ties in the catastrophic upheavals of the past with projections of what might be in store for us: heat waves, famine, rampant infectious disease, and drought, just for starters. The good news: If we manage to curtail carbon-dioxide emissions now, concentrations of greenhouse gases could decline, which could, in turn, mitigate the worst of global warming’s effects.
Ward warns:
We as a worldwide society can keep carbon dioxide levels below 450 parts per million. If we do not, we head irrevocably toward an ice-free world, which will lead to a change of the thermohaline conveyer belt currents, will lead to a new greenhouse extinction. The past tells us that this is so.
Or else, in 10 words or less (Mr. Ward, please take note): Ay caramba.
This review refers to an advanced readers’ copy from Harper-Collins. Under a Green Sky: Global Warming, the Mass Extinctions of the Past, and What They Can Tell Us About Our Future can be found in stores beginning April 17.
