A refrain running through the debate over global warming suggests we need to do nothing to slow it, because after all, the climate science predicting more warming could turn out to be wrong. Giordano Bruno was burned at the stake, and Galileo almost was, for objecting to the scientific doctrine that the Sun revolves around the Earth. For two thousand years people believed in systems of physics and astronomy that turned out to be incorrect. And for a few more centuries after that they held to a new celestial mechanics only to see it displaced by relativity theory.
Following publication in 1962 of Thomas Kuhn's seminal Structure of Scientific Revolutions, science historians heatedly disputed the question of whether Einstein had shown Newtonian physics to be wrong, as Kuhn argued, or merely incomplete. But surely the important point, from a practical point of view, is that Newton's physics made predictions that were mostly true; for that matter, the same went for Aristotelian physics and Ptolemaic astronomy, which after all recognized that objects fall down not up and accurately described the movements of celestial objects to a very refined degree.
The plain fact of the matter is that when it comes with dealing with real-world problems on a day-to-day basis, we have no choice but to proceed on the basis of the science we have. Steven Hochstadt, a PhD historian who teaches in Illinois, made the point nicely in a recent newspaper column in which he considered climate science in the context of issues he encounters in caring for his aging mother.
"The medical and scientific uncertainties connected with my mother’s health are a very immediate concern. Although most days are similar and uneventful, sometimes crucial decisions must be made within hours. Everyone must be ready to think about all the evidence we have, all the alternatives for action or inaction....
"Medicine is a highly developed branch of science. In other kinds of science, there is usually much less pressure to come to a decision. ... The more distant a particular kind of science is from our immediate needs, the more resistant people can be to reaching potentially unpleasant conclusions.
"Global warming is a good example. Thus far, warming has had little effect on most people’s lives and it will be years, even decades, before the consequences of climate change affect our daily lives, or those of our children and grandchildren. So the necessity of paying attention to all the evidence, of applying careful logic, of reaching careful conclusions, can easily become subordinated to wishful thinking and unwillingness to abandon comfortable assumptions."
To put it bluntly, would you defy the medical consensus and risk allowing your mother to suffer needlessly or die, just because the medical consensus might turn out to be wrong?
Hochstadt is surely right that people are reluctant to accept unpleasant conclusions and take costly actions, as long as really dangerous developments seem far-off. But he may somewhat overstate just how distant dangerous developments are and understate the possibility of catastrophic changes taking place at any time. His own region of the country, the American Middle West, is susceptible to adverse consequences that could drastically affect its status as one of the world's great breadbaskets.
Don Wuebbles, a prominent climate scientists at the University of Illinois, Urbana-Champaign, has been pointing out for years that if present-day trends continue, by the end of this century, Illinois's climate will closely resemble that of East Texas. Though East Texas is by no means a wasteland, not a lot of corn grows there, as followers of Wuebbles have pointed out online.
Somewhat paradoxically, global warming can make a region more arid and yet more vulnerable to the occasional devastating rainstorm. And in fact, one recent study finds that the frequency of heavy rainstorms in the Middle West has increased more than 50 percent in the last decade.
“Global studies already show that human-caused climate change is driving more extreme precipitation, and now we’ve documented how great the increase has been in the Midwest and linked the extreme storms to flooding in the region," commented Stephen Saunders of the Rocky Mountain Climate Organization, which did the study with the Natural Resources Defense Council. "A threshold may already have been crossed, so that major floods in the Midwest perhaps now should no longer be considered purely natural disasters but instead mixed natural/unnatural disasters."