January 22, 2011
Elizabeth Kolbert's Field Notes from a Catastrophe, subtitled "Man, Nature, and Climate Change," is based on a series of articles that appeared in the New Yorker over the last several years. As you can guess, it deals with the topic of global warming, or, as we have now been taught to say, climate change. Kolbert's writing is very vivid and concrete. She has traveled to research sites around the world — to the Alaskan tundra, the glaciers of Greenland, the below-sea-level towns of the Netherlands — and interviewed many of the scientists who are collecting the data that is used as input to climate modeling: core samples of glacial ice and ocean sediments, ranges of biological species, sea ice coverage, and so on.
On first reading in the New Yorker, I thought Kolbert made a convincing case that global warming is among the most urgent threats to human society and to the planet as a whole. But partly in response to "climategate," the November 2009 pushback by global warming skeptics, I read Kolbert's book with a more skeptical attitude. I am still a global-warming "believer" — just as I am a believer in the laws of physics and thermodynamics and the theory of evolution. But I tried to read at Kolbert's narrative as a global-warming skeptic might, looking for soft spots in her assumptions or data.
If you consider yourself a global-warming skeptic, I urge you to read her book and consider the facts that she presents. Shoot down her arguments if you can. The crux of the issue is atmospheric concentrations of CO2 (carbon dioxide), concentrations which have been around 250 ppm (parts per million) for thousands of years, but are on track to double, to 500 ppm, by the middle of this century, and triple by the end of the century. The record from the ice cores shows that CO2 concentrations are closely correlated with global average temperatures; that today's CO2 concentrations are off the charts compared with recent geological history (the previous high of 229 ppm having been reached 325,000 years ago); that human burning of fossil fuels is causing the CO2 increase; and that today's global average temperatures are nearly as high as at any time in the last 420,000 years. We are heading into unkown territory, with CO2 levels higher than they have been in probably millions of years.
(I have heard the argument that 250 ppm is only 0.025 percent of the total atmosphere, so a doubling to 500 ppm is only a 0.025 percent change in the composition of the atmosphere, so must be insignificant! "Small" amounts of toxic substances are never a problem, right? This is the same magical thinking that figures it's OK to dump "small" amounts of toxics into "large" waterways, and that comes to an abrupt end when people realize their river has become a sewer.)
But I'm not trying to argue the case for global warming here, only that you should read Kolbert's excellent book and decide for yourself. That's the end of my review. But I would like to make a separate point about risk management.
Vice President Dick Cheney, in response to the 9/11 attacks by Al Qaeda, was quoted as saying that given "a one percent chance" of a future terrorist attack, "we have to treat it as a certainty in terms of our response." Based on the perceived remote possibility of a further threat from a handful of terrorists hiding in caves in the Afghanistan/Pakistan border, the US started two wars, curtailed civil liberties, committed thousands of lives and trillions of dollars, and sent the nation on a downward path.
And yet, when it comes to the risk of global climate change, we seem to be following a 99 percent doctrine — we have to be absolutely certain that the threat of global warming is real before we can do anything.
Today's papers had two interesting pieces of news. First, scientists have found that the loss of polar ice and resulting increased absorption of solar energy is raising polar temperatures even faster than projected. Second, the US House of Representatives is planning legislation to prevent the EPA from any "job-killing" regulation of CO2 emissions. In other words, government policy seems to be based on some combination of the following assumptions:
With these kinds of arguments, global warming skeptics have planted doubts in the public mind about the validity of the scientific projections — the science is "not settled," they say. And we should wait for certainty before we do anything. (Kolbert's book presents significant evidence against each of these arguments.)
Now let me ask you what level of global warming risk you think is acceptable. What if there is a one percent risk of passing a threshhold that "flips" the planet's climatic equilibrium and makes the worst-case projections come true — of sea levels rising by tens of feet, of major agricultural regions turning to desert and becoming uninhabitable, of much more extreme weather events such as storms and droughts (and resulting floods and forest fires), of water supplies drying up, of a large percentage of the planet's species (including, possibly, humans) going extinct? Now, that would be a job-killer.
What level of risk is acceptable? One percent? Fifty percent? Do we need to be 99% certain before we do anything? The global warming skeptics like to say that the science is unsettled, but seem to be claiming 100% certainty for their position!
The whole thing reminds me of the "debate" about whether smoking causes cancer. It is true that some people smoke all their lives and die of something other than cancer. So smokers can rationalize that the probablity of cancer is somewhat less than 100%. There is some chance that they will get off scot free. And any one cigarette produces no drastic consequence. One after another, nothing much seems to change. So you say, I smoke, yet I'm cancer-free.
Then one day the risk jumps to 100%, and you say I'm gonna die and it's too late now and I wish I had listened to the Surgeon General. Or you say now I'm going into the hospital and have them fix the problem.
This is exactly the approach the US is taking to global warming. We need to see some (more) drastic consequences before we commit to doing anything. Then we will somehow adapt to the situation. The only question is, how bad does it have to get before we act?