Take precautions: global warming deserves it

Book reviews are not always reviews of books. In the big review magazines they are an excuse to sound off. The latest New York Review of Books contains an absolute lulu, a piece that ought to be required reading for sane people everywhere. Alas, it doesn't seem to be getting a whole lot of traction.

Jim Hansen, Director of the NASA Goddard Institute for Space Studies and Adjunct Professor of Earth and Environmental Sciences at Columbia University's Earth Institute, lays it on the line in a superb piece called The Threat to the Planet.
Hansen is ostensibly reviewing three books and a film about climate change. You can guess the film: Al Gore's An Inconvenient Truth. Hansen's point, which he makes with great clarity, is that "business as usual" may trigger an unstoppable catastrophe, with positive feedback loops amplifying small changes. Ice melts into water. Water sits on top of the ice, increasing the amount of heat it absorbs, and increasing melting. Water penetrates to the base of the ice shelf, lubricating the ice and helping it to calve icebergs. A lighter ice shelf sinks lower, where it is warmer, where it melts faster.

You get the picture. And if you don't, go read the article. It ought to shock you.

We need to take the possibility of global warming seriously. Now. Wired's Tony Long agrees.

If the "alarmists" are right, even partly right, and we do nothing, all of our other worldly concerns -- whether it's peace in the Middle East or rising interest rates or the happiness of Shiloh Nouvel Jolie-Pitt -- will amount to Humphrey Bogart's proverbial hill of beans.

The Economist, naturally enough, does not. It has always taken the side of those who want to save money now versus those who want to save the world, later.

For climate change, the trouble is that though few dispute that it is occurring, no one knows how severe it will be or what damage it will cause. And the proposed solutions are staggeringly expensive. Mr Lomborg reckons that the benefits of implementing the Kyoto protocol would probably outweigh the costs, but not until 2100. This calculation will not please Al Gore. Nipped at the post by George Bush in 2000, Mr Gore calls global warming an "onrushing catastrophe" and argues vigorously that curbing it is the most urgent moral challenge facing mankind.

Mr Lomborg demurs. "We need to realise that there are many inconvenient truths," he says.

Indeed. And if global warming could wait, I would agree that boosting vitamin A for poor children would be a higher priority.

Can global warming wait? Jim Hansen, and many other scientists, don't think so. Five degrees Fahrenheit warmer -- the average predicted under business as usual -- translates to a rise in sea level of 80 feet. As Hansen says:

Fifty million people in the US live below that sea level. Other places would fare worse. China would have 250 million displaced persons. Bangladesh would produce 120 million refugees, practically the entire nation. India would lose the land of 150 million people.

Better give those Indian and Bangladeshi children plenty of vitamin A; they're going to need to see where to go.

At stake is how cautious we really ought to be. All the science suggests that continued global warming will indeed give rise to Gore's onrushing catastrophe. Worse, it suggests that by the time those in charge see the light, it may be too late to do anything at all, no matter how much money and technology they are then willing to throw at the problem.

p.s. Hansen's article is thorough, readable, and scary. I set out to write a different post. That one can wait. Climate change cannot.