Tornadoes, Extreme Weather And Climate Change, Revisited

Of course, we've always had severe weather. But global warming is adding energy to our system, which would be expected to make for more extremes. Like if you shove the ground harder when you are swinging, you expect to go higher.

http://thinkprogress.org/climate/2013/05/21/2040221/tornadoes-extreme-weather-and-climate-change-revisited/

By Joe Romm on May 21, 2013

Tom Karl, the director of the National Climatic Data Center, explained in a 2011 email:

What we can say with confidence is that heavy and extreme precipitation events often associated with thunderstorms and convection are increasing and have been linked to human-induced changes in atmospheric composition.




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The main climate change connection is via the basic instability of the low level air that creates the convection and thunderstorms in the first place. Warmer and moister conditions are the key for unstable air.

The climate change effect is probably only a 5 to 10% effect in terms of the instability and subsequent rainfall, but it translates into up to a 32% effect in terms of damage. (It is highly nonlinear). So there is a chain of events and climate change mainly affects the first link: the basic buoyancy of the air is increased. Whether that translates into a super-cell storm and one with a tornado is largely chance weather.

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