Engineers are people of action, not just words. But even if we believe what we are often told about climate change, it's not at all clear what we should do about it.
Last week, I attended a meeting at which a highly credentialed professional meteorologist outlined the history of the science of climate change from the nineteenth century to the present. Prof. Andrew Dessler of Texas A&M's Department of Atmospheric Sciences described how as long ago as the 1890s, Swedish scientist Svante Arrhenius calculated that the small concentration of carbon dioxide in the atmosphere (then around 300 parts per million) had a disproportionate effect on the earth's temperature. Regular monitoring of this concentration began in the 1950s, and by then it was clearly understood that more carbon dioxide means higher temperatures. Dr. Dessler said that for at least fifty years, there has been a consensus that the present human-caused increase in carbon dioxide in the air will eventually lead to a rise in global average temperatures of "a few degrees C."
So far I was with him. Other things being equal (which they never are), more greenhouse gases in the air (of which carbon dioxide is one) means the planet gets warmer. But then he started talking about cigarette smoking, and how the tobacco industry mounted a cynical disinformation campaign in the 1960s against the overwhelming evidence that smoking caused lung cancer and heart disease. Because it took about forty years for the scientific truth to change public policies (you began to see smoke-free campuses and workplaces only about ten years ago), Dr. Dessler thinks it may take that long for the U. S. to get serious about global warming. Personally, I think it will take longer than that, because the two cases are more different than they are similar.
As someone else in the audience pointed out, smoking has highly specific individual consequences. As long ago as 1964, anyone who read a newspaper knew that by smoking, you made it a lot more likely that you would die early and fast, the way my father died of lung cancer at 57 only a year after he was diagnosed. If driving a Humvee increased your personal chances of having your own house wrecked by a tornado by the same degree as smoking increases your chances of causing lung cancer, what would happen? Well, for one thing, Humvee owners would have a lot of trouble getting home insurance. And sales of Humvees would fall.
But in contrast to the smoking-cancer tie-in, the actions that contribute to climate change, and the possible (I emphasize "possible") consequences, are about as far removed as you can get and still stay on the same planet. From what little I know about the matter, it appears that the most widespread and likely consequence of letting the earth's average temperature rise a few degrees Celsius is that a lot of ice will melt, water will expand, and the ocean's average levels will rise. Let's leave aside all the other stuff—species extinction, storms, and other changes in weather patterns—and concentrate on just that one thing.
About 44% of the world's population in 2010 lived within 150 km (94 miles) of the sea. And many of the world's most populous cities are coastal ones, or so close to the coast that a significant rise in ocean level would cause them major problems. Now if all the ice in Antarctica melted, the ocean's level would rise some 61 meters (200 feet). So in that case, good-bye Hong Kong, New York, and Florida. But to my knowledge, no serious scientist has proposed that the entire ice sheet covering Antarctica is going to melt because of human-induced climate change. So the fact is that you have a range of estimates of how much the oceans will rise, but all of them are much less than 61 meters. They may be well-educated estimates, but that's all they are—estimates.
So instead of a single increased chance that you, individually, will suffer about the most serious consequence you can encounter—death—as a result of your individual actions, your individual motivation to do something about climate change is that somebody, somewhere, possibly but not certainly near a coastline, might eventually have to move or suffer an increased chance of getting flooded out in a storm. And that person might be you, but not for another few decades, anyway. And even if you become a hyper-climate-conscious zero-carbon-footprint fanatic, your solitary actions will be fruitless unless billions of people all across the world do likewise, or at least move in that direction.
Personal versus impersonal, individual versus transnational, death versus some fuzzy probabilistic consequence for many people you will never meet—at the point of political action, the analogy between smoking and burning fossil fuels collapses. There is also the little matter of the difference in economic importance of the two industries in question. If the entire tobacco industry vanished tomorrow, life could go on more or less normally for most of us, but if the entire fossil-fuel industry vanished tomorrow, a large number of us would die in a matter of weeks for lack of basic necessities. That is a big downside cost to the proposal to something about climate change fast.
Prof. Dessler sees a global carbon tax as the way forward. He thinks if the U. S. slapped a big carbon tax on imports, that the rest of the world would fall in line and come along quietly. A global tax high enough to put significant brakes on fossil fuel consumption now would likely do something similar to what the Smoot-Hawley Tariff of 1930 did. Most economists believe that those extremely high U. S. tariffs contributed significantly to the worldwide depression of the 1930s, and punitive carbon taxes imposed on countries that don't get in line with reduction in fossil-fuel use would probably trigger a global depression that would make the 1930s one look like a mild headache in comparison.
From an engineering point of view, achieving the goal of transitioning from a global economy based on fossil fuels to one in which fossil-fuel use is cut to a small fraction of its present rate is logically possible. But achieving it in a way that is just and fair, and imposes hardships less than those otherwise suffered from whatever climate change would result, is an immensely challenging technical and political task, and would require a degree of coordination and cooperation that is unprecedented in world history.
Maybe it will happen. But if history is any guide, something really awful, and unequivocally attributable to climate change, will first have to happen worldwide, in order to create the political will to act.
Sources: Prof. Andrew Dessler spoke at the Lone Star Historians of Science meeting at Texas A&M University on Apr. 11, 2014. I referred to Charles Krauthammer's column on climate change carried by the Washington Post on Feb. 20, 2014 at http://www.washingtonpost.com/opinions/charles-krauthammer-the-myth-of-settled-science/2014/02/20/c1f8d994-9a75-11e3-b931-0204122c514b_story.html, and Daniel Yergin's history of climate change at http://danielyergin.com/history-of-climate-change/.
The statistic about ocean levels and Antarctica is from http://science.howstuffworks.com/environmental/earth/geophysics/question473.htm. And for how a qualified opponent of the conventional view of climate change, Prof. William Happer, was received at another professional meeting, see my blog "When Scientists Aren't Scientists" on Oct. 7, 2013.
