A lot of IFs, ANDs and BUTs and extrapolating
IF Katrina hit somewhere else (which it didn't) it would have done more damage than a hurricane that hit the same spot 117 years ago (IF the same spot had the same developments)
Remembering the 1900 Storm ...
Facts about the 1900 Storm:
? 8.7 feet: The highest elevation on Galveston Island in 1900.
? 15.7 feet: The height of the storm surge.
? 28.55 inches: Barometric pressure recorded in Galveston, 30 miles from where the eye of the storm is best estimated. At the time, this was the lowest barometric pressure ever recorded.
? 6,000 to 8,000: Number of people estimated to have died during the storm.
? 37,000 people: Population of Galveston in 1900.
? 3,600: Number of buildings destroyed by the storm.
? 130 to 140 miles per hour: Speed meteorologists estimate the winds reached during the storm.
? $20 million: Estimated damage costs related to the storm. In today's dollars, that would be more than $700 million.

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