Angry in the Great White North

Hurricane Gustav was a Category 5 storm on the Saffir-Simpson Scale just a day ago.  And of course, the spectre of global warming was raised as the reason:

Global warming has probably made Hurricane Gustav a bit stronger and wetter, some top scientists said Sunday, but the specific connection between climate change and stronger hurricanes remains an issue of debate.

The Atlantic is seeing an increase in storms rated among the strongest. In the past four years, Hurricanes Gustav and Katrina, and six other storms have reached Category 4 or higher with sustained winds of at least 131 mph, according to research at Georgia Tech.

Six scientists contacted by The Associated Press on Sunday said this shows some effect of global warming, but they differ on the size of the effect.

"We are just seeing a lot more Categories 4 and 5 globally than we have ever seen," said Judith Curry, chairman of Earth and atmospheric sciences at Georgia Tech. "The years 2004, 2005 and 2007 are quite high. We're just seeing more and more."

Uh-huh.  Of course, our Green Party has no doubt:

The intensity of hurricanes is increasing. While some hurricane specialists are not yet convinced, increasingly research at MIT and Princeton demonstrate that the energy packed in the hurricane’s punch has increased by 50-80% from 1950 to 2003.  Warmer waters in the ocean lead to more severe hurricanes. In the fall of 2003, Hurricane Juan was the first full force tropical hurricane ever to slam into Nova Scotia. Normally, cooler ocean water to our south would have down-graded Juan to a tropical storm, but it hit Nova Scotia as a full force tropical hurricane.

Right.  One storm, and the Green Party knows the reason.  And from that, the Green Party states unequivocally that hurricanes are getting worse.

So what has happened with Gustav?  It makes landfall as a Category 2 storm:

Hurricane-force winds slammed into oil terminals around Port Fourchon, southwest of New Orleans, as the eye of Category 2 Gustav was churning just off the Gulf shore Monday morning, according to radar.

The eye of Hurricane Gustav made landfall near Cocodrie, Louisiana, about 9:30 a.m. CT (10:30 a.m. ET), the National Hurricane Center said.

Winds were sending whitecaps over levees in New Orleans, but the U.S. Army Corps of Engineers reported no major problems.

Hey, I'm not a climatologist, but I can tell you something that any engineer can tell you.   If global warming is real, then you'll get weaker hurricanes, not stronger ones.

Like any engine, the amount of extractable work is limited by the difference driving the engine.  That could be the difference in voltage across the contacts for an electric motor, or the difference in pressure on either side of piston in an internal combustion engine, or the difference in height between the top and bottom of a dam feeding falling water to a hydro turbine.

A storm is the same.  The difference in temperature across broad swaths of ocean drive hurricanes.  The more dramatic the difference in temperature, the more energy can feed the storm.

If global warming is making temperate zones more tropical, then the difference in temperature will drop, and it will be difficult to sustain high intensity storms.

Of course, every storm is the consequence of localized conditions at the time the storm is formed, but in general, the likely effect of global warming is to make intense storms a rarity instead of the norm.

But then Category 2 storms ("Storms of this intensity damage some roofing material, and also produce damage to poorly constructed doors and windows") are so much less sexier than Category 5 storms ("Only a few types of structures are capable of surviving intact, and only if located at least three to five miles (four to eight km) inland"), and when it comes climatology and global warming, it's always been about showmanship instead of science.  Or even common sense.