Two years ago, I posted an item here about the possibility of a category-5 hurricane hitting New Orleans. Go here and scroll down, or just read this:

Five years ago, I read a fascinating piece in the Wall Street Journal by Sebastian Junger (author of the huge bestseller The Perfect Storm) on hurricanes. It was right after Hurricane Georges blew through Louisiana, and Junger described what a disaster it would be for New Orleans if a Category 5 hurricane blasted its way through the city. (Hurricane Isabel recently was Category 5; currently it’s Category 3, with 115 mph winds.) Levees retain all the water in the Mississippi River and Lake Pontchartrain. If they failed, the city would flood, trapping thousands and drowning many. He also made an interesting point: We’re better able to prepare for hurricanes today because of improved weather forecasting. But we’re also more vulnerable: “Unfortunately, the [infrequency of hurricanes] of the 1970s and ’80s occurred during a massive building boom along the East Coast. Since 1960 the population of southern Florida has roughly tripled, and the total number of people living along the Gulf and Atlantic coasts has gone up by over 50%. With the thermohaline circulation now reversing itself again, increased hurricane activity has resulted in a sudden escalation of property damage along the coast. Hurricane damage for the 1990s is already 30% higher than for the 1970s and ’80s combined. According to Roger Pielke of the National Center for Atmospheric Research, the last major hurricane to hit Miami, in 1926, caused only $1.4 billion worth of damage (adjusted for inflation). Were that same storm to hit today, the price tag would be $70 billion.”