As the planet continues to warm up, and as serious efforts to address climate change continue to be impeded by a combination of lobbyist money, lazy media and, quite frankly, willfully ignorant and selfish morons who get their scientific insights from Rush Limbaugh and Matt Drudge, it's worth listening to the words of wisdom from a Harvard economics professor who has spent years studying the economics of global warming. Weitzman lays out his arguments in favor of taking action in this essay for PBS Newshour's "The Business Desk." His essential argument is that taking action to reverse the increase in CO2 makes perfect sense from a risk-analysis perspective. I've stitched together some of Weitzman's main points below, but the entire piece is well worth reading.
The current CO2 concentration of 400 ppm is some 40 percent higher than anything that has been attained in the last 800,000 years. The glacial-interglacial cycles began some two and a half million years ago. Scientists estimate that a CO2 concentration of 400 ppm has not been attained for at least 3 million years. This rapid a change in CO2 concentrations has probably not occurred for tens of millions of years.
The point here is that we are undertaking a colossal planet-wide experiment of injecting CO2 into the atmosphere that goes extraordinarily further and faster than anything within the range of natural CO2 fluctuations for tens of millions of years. The result is a great deal of uncertainty about the possible outcomes of this experiment. The higher the concentrations of CO2, the further outside the range of normal fluctuations is the planet, and the more unsure are we about the consequences. ...
If we were to continue CO2 emissions to an atmospheric concentration of 800 ppm of CO2, the IPCC formula translates into an ultimate average temperature change of 4.5 C (8.2 F) with a likely range between 3 C (5.4 F) and 6.8 C (12.3 F). The world has not seen this level of CO2 concentrations for some 50 million years, when crocodiles and palm trees thrived in the Arctic Circle, Greenland and Antarctica were ice-free, and sea levels were hundreds of feet higher than today. ...The significance of just having blown past 400 ppm is that we seem to be on a business-as-usual growth trajectory that brings us to 800 ppm (or maybe even more) within a century from now. ...[C]limate change damages from high levels of greenhouse gas concentrations are enormously uncertain. ...[F]or an economist, abating CO2 emissions is like buying insurance against a catastrophe. We should cut back on CO2 emissions not only to lower the average damages, but, perhaps more importantly, to lower the probability of catastrophic damages.
As for the global warming skeptics, Weitzman asks, "Are they or the mainstream climate scientists more right than wrong? [C]an we afford the luxury of assuming that a small minority of climate skeptics are more correct than the vast majority of mainstream climate scientists? What is the probability of that?" Good question! The answer, at least to any rational, objective human being, is 0%. There' a zero percent chance that the global warming skeptics are right, while the vast majority of mainstream climate scientists are wrong. It's plain silliness to believe otherwise. Actually, it's far worse than that, as Weitzman concludes: "The bottom line is that if we continue on a business-as-usual trajectory, then there is some non-trivial probability of a catastrophic climate outcome materializing at some future time. Prudence would seem to dictate taking action to cut back greenhouse gas emissions significantly. If we don't start buying into this insurance policy soon, the human race could end up being very sorry should a future climate catastrophe rear its ugly head." And the victims will be people who aren't around now to make their voices heard. We need to do better, and fast. Now read this: