I’ve grown accustomed to it over the years. I’ve never been fully convinced that Global Warming was really happening, and I’ve never concealed my opinions to that effect. As a result, I’ve been called any number of derogatory epithets, leading off with “denier,” a throwback to the Germans (and a few others) who steadfastly refused to believe that the Third Reich was systematically eliminating Jews, gays, and other human beings they considered undesirable. But questioning GW is markedly different from denying the Holocaust; there are solid, massive amounts of evidence, including eyewitness accounts, to document Hitler’s Final Solution.
Global Warming, on the other hand, is supported by far less real, tangible evidence, and much of the theory hangs on the predictions of computer models, which in most sciences are a useful tool, but because they can and do tend to be imprecise, only on a theoretical level. Indeed, one such model, Michael Mann’s infamous “Hockey Stick” graph proved to be so distanced from reality as to become a world wide laughingstock. And, of course, we GW deniers aren’t denying (and thus excusing) genocide. As I said, there’s a difference.
But the real difference lies in the reality of what has been transpiring in Earth’s atmosphere. For 15 years, nearly the past two decades, the atmosphere has not warmed, even though carbon dioxide released into it is increasing; an estimated 100 billion tons of CO2 were added to the atmosphere between 2000 and 2010.
Now, before all you true believers rise en masse to crucify me, let me assure you that it is not my intention to flat-out deny the possibility of GW. Just as I believe there is not enough good evidence to confirm its existence beyond the shadow of a doubt, so too, one cannot at this point say, “That’s it, folks, move on; nothing to see here,” like a cop at an accident scene. What does seem to be happening, however, is that there is now, on the part of some scientists, a modicum of doubt, at least as to the potential severity of the GW phenomenon; a doubt that, for many of these scientists and government officials, did not exist until now. Concurrent with the emergence of that doubt, we are now seeing some of the scientists themselves taking a second look at their computer models and other data, seeking explanations for what at the moment, are puzzling anomalies that are not congruent with much of the thinking until now. Even NASA’s James Hansen, one of the chief standard bearers for Global Warming theory, has observed publicly, “The five-year mean global temperature has been flat for a decade.”
The question of what is actually going on is centered on what the scientists term, “Climate Sensitivity,” which, as its name implies, simply refers to how much (or how little) the climate will react to changes in CO2 levels over time. According to the UK’s venerable conservative (in the American sense) journal, The Economist,
This is usually defined as how much hotter the Earth will get for each doubling of CO2 concentrations. So-called equilibrium sensitivity, the commonest measure, refers to the temperature rise after allowing all feedback mechanisms to work (but without accounting for changes in vegetation and ice sheets).
The rule of thumb for the effect that CO2 has on the atmosphere’s temperature has been that each doubling of the amount of absorbed carbon dioxide in the atmosphere will result in roughly a 1 degree Celsius rise in its temperature. There are, however, other variables which complicate this theory. As The Economist notes, these variables complicate predictions for two reasons: