Abstract. By American standards, New Orleans is a very old, very popular city in the southern part of the United States. It is located in Louisiana at the mouth of the Mississippi River, a river which drains about 40% of the Continental United States, making New Orleans a major port city. It is also located in an area of major oil reserves onshore, as well as offshore, in the Gulf of Mexico. Most people know New Orleans as a tourist hotspot; especially well-known is the Mardi Gras season at the beginning of Lent. People refer to the city as the "Big Easy". A recent biography of the city refers to it as the place where the emergence of modern tourism began. A multicultural city with a heavy French influence, it was part of the Louisiana Purchase from France in early 1803, when the United States bought it, doubling the size of the United States at that time. Today, in the year 2007, New Orleans is now known for the devastating impacts it withstood during the onslaught of Hurricane Katrina in late August 2005. Eighty percent of the city was submerged under flood waters. Almost two years have passed, and many individuals and government agencies are still coping with the hurricane's consequences. And insurance companies have been withdrawing their coverage for the region. The 2005 hurricane season set a record, in the sense that there were 28 named storms that calendar year. For the first time in hurricane forecast history, hurricane forecasters had to resort to the use of Greek letters to name tropical storms in the Atlantic and Gulf (Fig.~1). Hurricane Katrina was a Category 5 hurricane when it was in the middle of the Gulf of Mexico, after having passed across southern Florida. At landfall, Katrina's winds decreased in speed and it was relabeled as a Category 4. It devolved into a Category 3 hurricane as it passed inland when it did most of its damage. Large expanses of the city were inundated, many parts under water on the order of 20 feet or so. The Ninth Ward, heavily populated by African Americans, was the site of major destruction, along with several locations along the Gulf coasts of the states of Mississippi and Alabama, as well as other parts of Louisiana coastal areas (Brinkley, 2006). The number of deaths officially attributed to Hurricane Katrina was on the order of 1800 to 2000 people. The cost of the hurricane in terms of physical damage has been estimated at about US $250 billion, the costliest natural disaster in American history. It far surpassed the cost of Hurricane Andrew in 1992, the impacts of which were estimated to be about $20 billion. It also surpassed the drought in the US Midwest in 1988, which was estimated to have cost the country $40 billion, but no lives were lost. Some people have referred to Katrina as a "superstorm". It was truly a superstorm in terms of the damage it caused and the havoc it caused long after the hurricane's winds and rains had subsided. The effects of Katrina are sure to be remembered for generations to come, as were the societal and environmental impacts of the severe droughts and Dust Bowl days of the 1930s in the US Great Plains. It is highly likely that the metropolitan area of New Orleans which people had come to know in the last half of the 20th century will no longer exist, and a new city will likely replace it (one with a different culture). Given the likelihood of sea level rise on the order of tens of centimeters associated with the human-induced global warming of the atmosphere, many people wonder whether New Orleans will be able to survive throughout the 21st century without being plagued by several more tropical storms (Gill, 2005). Some (e.g., Speaker of the US House of Representatives Hastert) have even questioned whether the city should be restored in light of the potential impacts of global warming and the city's geographic vulnerability to tropical storms.
RECONNAISSANCE LEVEL STUDY MISSISSIPPI STORM SURGE BARRIER
