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.
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