The increase in wind shear is not an isolated phenomenon, and so must be put into the context of a warming world where there is an increase in hurricane activity as well.
"We just don't know how the two of them will combine."
Vecchi and Brian J. Soden of the University of Miami used 18 climate models to assess factors linked to hurricane formation from year 2000 to 2100.
The different simulations mimic how certain systems would interact with each other under various climate scenarios.
Specifically, the researchers looked at how the wind shear over the Atlantic ties to the Pacific Walker circulation, a pattern of airflow above the equatorial Pacific Ocean that affects climate around the globe.
The results showed that, in response to rising temperatures, there would be a slowing of the Pacific Walker circulation, which would increase wind shear.
Averaging Results
Kerry A. Emanuel is a professor of atmospheric science at the Massachusetts Institute of Technology.
He said, "I think it's a very interesting study, and the technique they're using is pretty good."
"The only reservation I have about it is, to do this, [the researchers] took the output from 18 climate models and they kind of averaged these results," said Emanuel, who was not involved in the study.
They're "averaging a lot of things together to get a consensus, which is almost like treating these models democratically. Not all models are created equal. Some of these models are pretty awful."
Emanuel has no doubts, though, that an increase in wind shear could have profound effects on hurricanes.
In a computer simulation he ran last year, Emanuel uniformly increased the wind shear by 10 percent, finding that it caused hurricane power to decrease by almost 12 percent.
"[This] is consistent with what [Vecchi and Soden] showed," Emanuel explained. "The problem is that the atmosphere that you get from averaging these results may not be the atmosphere that any one model could ever produce."
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