An expert Ehrlich consulted in picking the five was John Holdren, who today is President Obama's science adviser. Credentialed intellectuals, too -- actually, especially -- illustrate Montaigne's axiom: "Nothing is so firmly believed as what we least know."

As global levels of sea ice declined last year, many experts said this was evidence of man-made global warming. Since September, however, the increase in sea ice has been the fastest change, either up or down, since 1979, when satellite record-keeping began. According to the University of Illinois' Arctic Climate Research Center, global sea ice levels now equal those of 1979.

An unstated premise of eco-pessimism is that environmental conditions are, or recently were, optimal. The proclaimed faith of eco-pessimists is weirdly optimistic: These optimal conditions must and can be preserved or restored if government will make us minimize our carbon footprints, and if government will "remake" the economy.

Because of today's economy, another law -- call it the Law of Clarifying Calamities -- is being (redundantly) confirmed. On graphs tracking public opinion, two lines are moving in tandem and inversely: The sharply rising line charts public concern about the economy, the plunging line follows concern about the environment. A recent Pew Research Center poll asked which of 20 issues should be the government's top priorities. Climate change ranked 20th.

Real calamities take our minds off hypothetical ones. Besides, according to the U.N.'s World Meteorological Organization, there has been no recorded global warming for more than a decade, or one-third of the span since the global cooling scare.