As polarization over global warming intensifies an important question emerges: If the apparent pause in observed warming becomes an established trend, will politics change? The regrettable answer: probably not.
The urge to respond somehow to an increase over a century and a half in globally averaged temperature has come widely to be regarded as a measure not of scientific understanding but rather of personal conviction—even character. In Europe and the US, a generation has reached adulthood having been taught since elementary school that human activity emits greenhouse gases in an accelerating process that, unless reversed, dooms the planet to destructive warming. This analysis has bred a powerful political movement, cultivated a fertile area of academic research, established a priority metric for competitive diplomacy, stigmatized carbon dioxide as the greenhouse gas for which people are most responsible, encouraged governments to subsidize uneconomic energy forms containing no carbon and to punish hydrocarbons, and embedded itself in systems of personal belief.
And the analysis increasingly looks wrong.
Too simplistic
The popular analysis has always been too simplistic. Greenhouse gases do not represent the only warming influence and maybe not the strongest one. An increase in the atmospheric concentration of CO2—which, thanks largely to the use of fossil energy, seems lately to have occurred faster than expected—must have contributed to some extent to warming observed during the Industrial Age. But other influences exist. Prominent among them is solar activity. Offsets exist, too, prominent among them, clouds.
Warming influences, positive and negative, vary naturally. Their interactions are complex, difficult for computer models to account for, and so far poorly understood. If warming is to become catastrophic, as some computer models suggest, the interactions must play out so as to amplify the otherwise innocuous warming that would result if humanly emitted CO2 were the only factor. The probability is quite low that all the variables will align in a combination yielding worst-case scenarios. Measurements indicating no new warming for 10-15 years, depending on the data set and interpreter, lower the risk even further.
As it does with everything about global warming, of course, controversy envelops the proposition that the most frightening warming forecasts are losing credibility. Some observers express doubt that the temperature curve actually has flattened. Some point out that a 15-year data pattern does not represent a trend in the climate record. Those are wholesome issues for scientific dispute. They deserve consideration in the politics of global warming. But so does the failure of recent temperature measurements to support the overly simplistic analysis that has driven politics thus far. The analysis flows from a theory that observation, at least for now, isn't validating.
On May 9, the National Oceanic and Atmospheric Administration said its observatory at Mauna Loa, Ha., recorded an atmospheric CO2 concentration of 400 ppm, a figure it lowered fractionally later in the month. It's the first time in perhaps 3 million years that the concentration has been so high. The increase is cause for concern.
Adjusting concern
Yet if the CO2 level continues to rise, which it will, and if measured temperature continues not to follow, the nature of that concern needs adjustment. A delinking of CO2 from temperature would—or should—ease fear about dangerous warming. It also would refute the theory undergirding not only modern energy politics but also thousands of academic and diplomatic careers and what millions of people think they know about the planet they inhabit. If such a delinking indeed is in prospect, widespread acknowledgment of it will take years to develop—maybe another generation.
Meanwhile, CO2 will continue to accumulate in the atmosphere. If that doesn't mean calamitous warming worthy of immediate and costly change to human behavior, it means something. But what? Amid the hysterics of global-warming politics, that question receives too little attention. Maybe that's because, as some scientists suggest, CO2 enrichment of the atmosphere might on balance be good for people.
