The standard charge against global warming is that its proponents, notably Al Gore, exaggerate its impact. Also, that there is considerable uncertainty in models that predict climate change into the far future. Climate change skeptics like Amit Varma use both arguments frequently, as in this post.
In a lesson in Probability 101, Professor Paul Klemperer points out if climate change skeptics are right, we need to worry more about climate change, not less. Both skeptics and proponents continue to argue about the average impact, while skeptics forget that their claim of greater uncertainty in prediction (or a higher standard deviation of the distribution) may point towards greater dangers. As Klemperer points out:
“Likewise, if our understanding of climate systems is flawed, our best guess about the dangers we face may be less pessimistic, but extreme outcomes are more likely”.