Weather and climate agencies around the world have been almost unanimous in declaring 2014 the hottest year on record — something that has promoted considerable chagrin among climate change doubters. That’s because these “skeptics” have long sought to cast doubt on man-made global warming by pointing to an alleged global warming “pause” or “slowdown” — going on to suggest that the computerized climate models that scientists use to project future temperatures are flawed, and overestimate carbon dioxide’s warming effect.

So, is that true? Do the models consistently overestimate the warming effects of greenhouse gases like CO2?

As a recent study suggests, the answer is no. While many models didn’t predict the relatively modest surface-warming “hiatus,” it’s not because they’re biased in favor of greenhouse-gas emissions’ warming effects. Rather, researchers report in Nature, these computer simulations just struggle to predict “chaotic” (or random) short-term changes in the climate system that can temporarily add or subtract from CO2 emissions’ warming effects.

No, climate models aren’t exaggerating…