Global heating: 2 questions; 2 answers

The first question is: how bad are things, really? The second: if things are as bad as the authors of two recent books on climate change say they are, are we capable of doing anything about it?

I've just finished The Revenge of Gaia: Earth's Climate Crisis & the Fate of Humanity by James Lovelock and Heat: How to Stop the Planet Burning by George Monbiot. Both authors are familiar to British readers. Both care deeply about the natural world, and both are very worried about where things are headed. Each book comes to similar conclusions -- (1) very bad and (2) yes, but only if we're very lucky -- but from very different directions.

Lovelock, the co-founder of the idea that the Earth behaves in a manner tantamount to a self-regulating organism, attracted a fair bit of attention early this year when he released his book just as a series of alarming (some would say alarmist) reports of melting glaciers, thawing permafrost and other harbringers of climatological doom were making the rounds of the usual media suspects. Not too surprisingly, he takes a big-picture approach, arguing that we have done near-irreversible damage to the planet's climate-regulating mechanisms.

Some have criticized Lovelock for embracing only the worst-case scenarios produced by climate-prediction models, and thereby behaving in a most unprofessional manner for a scientist. Hs book does suffer from the habit of making only minimal citations. Instead of footnotes or endnotes, we are asked to make do withsometimes vague mentions of so and so's study and brief chapter-specific "for further reading" lists, most of which container fewer than 10 references. Lovelock, it would seem, has been around long enough and produced sufficient meritorious science to warrant a pulpit of sorts. It's as if he's saying "I'm the world authority on planetary scale ecosystem regulation, so you can just take my word for it that I know what I'm talking about."

As you might expect this sort of attitude can be a bit maddening. Some of the time, though, he seems to make eminent sense. His fears that we are dangerously close to a threshold beyond which positive feedback will transform most of the Earth into a place that humans will find quite unfriendly (goodbye Class M status, to use a Star Trek phrase) are hard to argue with, given what we hear and read elsewhere.

For example, Lovelock writes that "The time of irreversible adverse change may be so close that it would be unwise to rely on international agreement to save civilisation from the consequences of global heating" (page 13). There isn't a lot of backup for such sweeping statements, but he respects his readers enough to supply hard data when absolutely needed. The turning point in question, he says, is an increase in atmospheric carbon dioxide levels to about 500 parts per million, a figure on which many others have settled. And the consensus is that such a level will result in a warming of another couple of degrees centigrade.

Just last week, we read that one of the world's leading climate specialists, NASA's Jim Hansen is at least as worried as Lovelock. In New Scientist he's quoted saying that:

"Further global warming of 1 C defines a critical threshold. Beyond that we will likely see changes that make Earth a different planet than the one we know."
...
Another decade of business-as-usual carbon emissions will probably make it too late to prevent the ecosystems of the north from triggering runaway climate change, [Hansen's] study concludes

At other times, Lovelock's lack of extraordinary evidence to support his extraordinary statements is more frustrating. The second half of the book largely concerns his prescriptions for forestalling irreversible climate change (if it isn't already too late) and no remedy is as important as building lots and lots of nuclear power plants.

It's here, where we tread on matters more economic than ecological, that Lovelock really should have done more research, or at least, provided proof that he'd done his research. And it's here that Monbiot proves the value of doing just that.

As a regular contributor to The Guardian on matters environmental, economic and political, Monbiot has built a still-youngish reputation as a radical but rational thinker. Where Lovelock rides on his own coat-tails, Monbiot stands on others' shoulders, including Lovelock's. Rather than a poetic overview of the coming nightmare, Monbiot offers a reductionist breakdown of each element of the problem and each possible response.

Monbiot also suspects we are on the verge of having gone too far. "Curtailing climate change must, in other words, become the project we put before all others," he says. He too believes we're less than a couple of degrees away from disaster. And he also thinks we've only got, at most, a couple of decades to get our act together. The difference is he provides upwards of 130 footnotes for each chapter to support his scare tactics.

Even if you grant that the scientific consensus on such predictions is both deep and wide, the simple fact that the targeted readers for both books probably aren't aware of just how dire things are warrants an approach closer to Monbiot's. Credibility is everything these days. It's not enough to know what you're talking about -- you have to show that you know exactly what you're talking about.

Like Lovelock, Monbiot is primarily concerned with the second question, and he devotes most of Heat to an exhaustive analysis of the various technology options available to deal with a world economy addicted to the one thing we can't afford to keep using. He also tackles nuclear energy, and comes up with what I think is a much more intellectually honest answer.

The bottom line for Monbiot is we really don't have enough information about nuclear power to evaluate its potential contribution. There's simply too much conflicting data about uranium supplies, safety concerns, disposal and decommissioning costs and so on. But given we've only got about 25 years to replace carbon-emitting power plants with cleaner alternatives, he concludes that we can't build new, safe reactors fast enough to displace sufficient megawatts of fossil-fuel plants to make a difference.

Monbiot's case -- we need to reduce our carbon emissions by 90 percent by 2030 and we can, if we start using a variety of renewables and carbon sequestering technologies now -- is convincing. But it's not iron-clad and at times seems almost naive. For one thing, while Monbiot focuses almost exclusively on what Britain can do, the developing world is given only a passing mention. Just today I came across a report in The Independent of a PricewaterhouseCoopers study of developing nation's expected economic growth that predicts "global carbon emissions will double by 2050" even if they reduce their energy use by 1 percent a year. Goodbye 500 ppm.

But Monbiot does take pains to qualify some of his source material, such as the highly controversial analysis of nuclear power presented by Van Leeuwen and Smith, which is good, because I find it hard to believe that a building a nuclear power plant actually requires more energy than the plant can produce over its operating life. And most importantly, he admits to a level of ignorance and ambiguity when appropriate.

Both Lovelock and Monbiot want us to get off our collective butts and do something. Lovelock uses broad scientific strokes and imagery (including color plates) to appeal to our emotional center, while Monbiot overwhelms us with data and logic. The former at times inspires and at others infuriates, leaving this reader unsure if there really is enough time to get our act together. The latter offers a more rational argument, but by embracing the scientific approach, one that recognizes uncertainty, also left me unconvinced that his ultimately hopeful conclusion is warranted.

In the end, both volumes are worth a read; one if you keep your skeptical hat on and the other if you appreciate an author who wears the hat for you.