tornado.jpgI am not saying the “unusually ferocious winter tornado system” that hit five southern states Wed. was caused by global warming. I am saying — or rather NASA is saying — we’re probably going to have to get used to it:

NASA scientists have developed a new climate model that indicates that the most violent severe storms and tornadoes may become more common as Earth’s climate warms.

So did John Kerry go too far on MSNBC when he said:

[I] don’t want to sort of leap into the larger meaning of, you know, inappropriately, but on the other hand, the weather service has told us we are going to have more and more intense storms,” Kerry said. “And insurance companies are beginning to look at this issue and understand this is related to the intensity of storms that is related to the warming of the earth. And so it goes to global warming and larger issues that we’re not paying attention to. The fact is the hurricanes are more intensive, the storms are more intensive and the rainfall is more intense at certain places at certain times and the weather patterns have changed.

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That sounds about right to me, though it wasn’t the “weather service” really, it was NASA. The conservative Business & Media Institute said Kerry was using the tragedy, which killed over 50 people, “to advance global warming alarmism.” But BMI embarrasingly undercuts its credibility by quoting one meteorologist from last year who obviously isn’t very good at forecasting:

Kerry’s assertion tornado activity is related to any type of climate change is questionable based on the writings of at least one meteorologist. Roger Edwards, a meteorologist at the Storm Prediction Center of the National Weather Center in Norman, Okla., has doubts about any global warming and tornado relationship.

As of this writing, no scientific studies solidly relate climatic global temperature trends to tornadoes,” Edwards wrote on the Earth & Sky Web site in April 2007. “I don’t expect any such results in the near future either, because tornadoes are too small, short–lived, hard to measure and count, and too dependent on day to day, even minute to minute weather conditions.”

Doh! NASA’s paper — “Will moist convection be stronger in a warmer climate?” — was actually submitted to Geophysical Research Letters in April 2007, and published in August!

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Significantly, yesterday the country saw an unusually powerful tornado system:

Tennessee Gov. Phil Bredesen, who flew over the disaster area Wednesday, said he was stunned by the storm’s power. Watch Bredesen describe a ‘nightmare’ [you’ll have to watch a commercial first]:

“I don’t think that I have seen, since I’ve been governor, a tornado where the combination of the intensity of it and the length of the track was as large as this one,” Bredesen said.

We have known for a while that global warming is making our weather more extreme, especially extreme heat, drought, heavy rainfall, and flooding. Now NASA says the “most violent severe storms and tornadoes,” should be added to the list. Perhaps that is why we have been setting records for tornados lately. This is especially bad news for this country because, as the study notes: “The central/east U.S. experiences the most severe thunderstorms and tornadoes on Earth.”

So, again, I wouldn’t say any specific tornado was caused by global warming, but we have been warned that we should expect to see more severe tornado systems on our current path of uncontrolled greenhouse gas emissions.