Models Predict More Intense Hurricanes in the near future . . . .

In a story from the AAAS/Science journal, it’s reported that fewer but fiercer and more-destructive hurricanes will sweep the Atlantic Basin in the 21st century as climate change continues, which is suggested from a new modeling study by U.S. government researchers.   Category 4 and 5 hurricanes may double in number by the end of the 21st century.

“The models seem to be converging,” says tropical meteorologist James Kossin of the National Climate Data Center’s office at the University of Wisconsin, Madison, who was not involved in the work. Plenty of uncertainties remain, Kossin notes, but compared with earlier studies, this one “is more credible; …it’s important.”

According to Science, what makes the new study more realistic is its sharper picture of the atmosphere. . . . . The high-resolution models used by the U.S. National Weather Service to forecast hurricane growth and movement …produce a realistic mix of both weak and strong storms, but those models can’t simulate global warming.

More big blows in the greenhouse. Computer simulation of the most intense hurricanes shows an increase from today (top) to a warmer world at the end of the century (bottom).

From the Science podcast this week, scientist Tom Knutson said, “We’re trying to understand how the most intense hurricanes in the Atlantic might change with climate warming in the 21st century, and we use models to do this. And our modeling results suggest that the frequency of these most intense Atlantic hurricanes—the category four and five hurricanes—will double over the course of the 21st century.”

“The group of scientists involved in the most recent research calculates that although the overall number of hurricanes would decline in a warmer world, they would still cause more damage, according to the modeling. Category 3 to 5 hurricanes have accounted for 86% of all U.S. damage despite constituting only 24% of U.S. landfalls, the group notes. That’s because when storms move up from one category to the next, the potential damage roughly doubles. . . . . The researchers note that the new modeling offers no support for claims that global warming has already noticeably affected hurricane activity. In the real world, the number of Atlantic hurricanes observed during the past 25 years has doubled; in the model, global warming would cause a slight decline in the number over the same period. Given that the mid-resolution model used by the group duplicates the observed rising trend, it may be natural. And the group estimates—very roughly—that so far any effect greenhouse warming has had on hurricane intensity should still be unrecognizable amid natural variations in hurricane activity.”

One scientist says the models themselves, so far, are uncertain that the Atlantic warming is actually caused by the greenhouse effect.  He also explains that the models don’t all predict the same thing due to “computer requirements”.  (Climate modeling takes up enormous computer resources and power.)  The Science podcast with this [...]