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Whoa!!! Katrina at one point had maximum sustained winds of 184milesperhour/296kilometresperhour
Extrapolating as if there were a maximum on Category5 in the standard Safir-Simpson Scale for the maximum sustained windspeed in each hurricane category:
Max.Cat.1 = 95mph/~154kph add 15mph/~24kph Max.Cat.2 = 110mph/~178kph add 20mph/~32kph Max.Cat.3 = 130mph/~210kph add 25mph/~40kph Max.Cat.4 = 155mph/~251kph add 30mph/48kph as if there were a Max.Cat.5 = 185mph/~299kph and Katrina was only 2mph/~3kph under the MinimumCat.6 = 186mph/~299kph if such a category actually existed.
The discrepency between mph and kph is because the next higher category of hurricane actually begins 1mph/1.61kph higher than the whole number at which previous category ends, so the Max.Cat.kph numbers must be rounded downward from 1mph higher rather than upward from the Max.Cat. mph numbers that I used. Just used 95mph/etc as the maximums because the actual 95.9...mph/etc would have been messier to write.
posted
Apparently, Katarina was a Cat.3 upon landfall, and either a low Cat.2 or high Cat.1 when hitting NewOrleans' levees.
Posts: 8501 | Registered: Jul 2001
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posted
aspectre, I'm skeptical about trusting ground over air data because I wonder how truly linear ground-based anemometers are at very high wind speeds. My gut reaction is unless they are routinely calibrated at those insanely high speeds, (which is quite unlikely) the little whirligig type anemometers are not going to respond as easily by increasing spin rate when you get up to those very high wind speeds.
Most machinery and measuring devices are not really linear in their response, but we engineers "linearize" them for the purpose of our measurements. That means we choose bearings, or other mechanical or electrical equipment, that responds more or less linearly over the range of conditions for which they are designed. At higher speeds, an anemometer would be suceptible to additional vibrations, bearing heating, and other forces which would have the effect of lowering its speed. Think about how a device designed to respond accurately on a gently breezy day would have to be stretched so far out of its comfort zone to measure hurricane winds.
However, an air-based measurement taken from the NOAA hurricane aircraft would be more likely to be calibrated to the range of wind speeds typically seen in a hurricanes. My gut feeling is that the aircraft-based readings would be more accurate.
There's also the consideration that during ANY storm, the wind speeds right at ground level are lower. That's why they tell you to get into a ditch if caught outside during a tornado. The purpose of assigning categories is to compare the relative strength of one hurricane to another. A particular ground level observation may be affected by all sorts of local topography, and have as much to do with where it was taken as it does with the hurricane's size. That would also make ground based observations open to a lot more interpretation. For that reason, too, I would tend to think the numbers from the air were more valid for comparison.
Posts: 6246 | Registered: Aug 2004
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posted
I had heard that Rita, though, was actually STRONGER than Katrina during the time it was out in the gulf and a category 5 -- something about the barometric pressure, etc. (saw that on one news interview with NOAA.)
Do you have comparison figures for Katrina v. Rita when they were at their height?
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That is amazing. I wonder how much of the city is fixed now after all this time? I heard it's still in pretty bad shape.
Posts: 6246 | Registered: Aug 2004
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From the position of someone who volunteers at a crisis center, mental health problems in Louisiana have gone crazy since the hurricane. Fewer services and more people needing them; definitely nothing like enough beds or counselors for all the people who need inpatient and outpatient mental health treatment. It's a mess. Stupid hurricanes.
Posts: 910 | Registered: May 2000
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I live on the other side of the lake but spend alot of time in the city.
There's been alot of rebuilding, but there's still so much damage. I still see people living in FEMA trailers, not too many anymore but that's also because I mainly do business in the less affected parts of time. Abandoned homes are particularly a big deal since no one can seem to decide how to handle so many properties that either need to be torn down or cleaned up.
We still have pretty big tent cities for the homeless. They were always there but they grew after Katrina and haven't gone down much since. There was a month a year ago where it seemed like there were numerous huge fires from the homeless taking sheltered in abandoned buildings. A recent news article described how this is still a huge problem.
My ex spent a year teaching in an elementary school in New Orleans East and would share his students' stories with me. I can't even imagine the horrors. Many watched friends and family drown and are still afraid that they'll be next when the next storm comes.
The government is as corrupt as ever and any progress should be credited to the citizens, volunteers, and organizations both local and national. But pre-Katrina recovery is a long time coming given the limited funds and manpower.
Posts: 1733 | Registered: Apr 2005
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