Question: If Revkin blames carbon dioxide for hot, dry weather this summer, and if that weather prevents tornadoes, shouldn't CO2 get credit for preventing tornadoes?

Twitter / Revkin: Tornado drought (probably ...

Tornado drought (probably record low for July) one upside of hot, dry summer in Midwest. @atmosnews provide... http://tmblr.co/ZtU9QyQ6yCwP

Flashback: The A, B, C's of Limiting Climate Risk - NYTimes.com

[Revkin] The report takes the approach used by the Intergovernmental Panel on Climate Change in its “reasons for concern” section and the diagram known as “burning embers” — both of which essentially illustrate how rising temperatures equate with rising risk in a variety of areas that matter to society.

Revkin assumes that a 60 degree F. world is obviously and measurably more risky than a 59 degree F. world, but how do we know that that's true? If warm weather has positive effects, such as maybe reducing tornadoes and reducing cold-related death and disease, maybe it's the 59 degree F. world that's more risky, or maybe the net difference in risk is too small to measure.

By the way, Revkin's suggestion that hot, dry weather reduces tornadoes points out a fundamental flaw in the whole "climate dice" warmist meme, where they encourage us to believe that warmer weather increases the risk of all possible bad weather, while reducing the probability of all possible good weather.