New Orleans and climate change
New Orleans was founded by the French colonist Jean-Baptiste Le Moyne de Bienville in 1718 on the relatively high natural levee along the Mississippi River (4.6m/15 feet above sea level). The city is the present day test case for world delta cities. After Hurricane Katrina collapsed the faulty levee system in 2005, 80% of the city flooded, forcing a prolonged evacuation of practically the entire population. At that time, New Orleans had a population of 437,186, down from a peak of 626,525 around 1960. Over the same period, despite population loss, the city’s area increased from approximately 100 square miles to its current size of 180 square miles. Since Katrina the population has fallen an additional twenty percent. The economy is made up primarily of oil, gas, and petrochemical industries, shipping traffic, seafood, and tourism.
New Orleans has a subtropical climate. Average annual temperatures fluctuate between 33° C in the summer and 6° C in the winter; annual rainfall totals typically exceed 1520 mm (59.8 inches). The Gulf of Mexico is prone to hurricanes; on average 11 hurricanes pass through the Gulf each year. In 2005 Katrina almost directly hit New Orleans as a massive category three storm with sustained winds up to 195 km (121.1 miles) per hour and storm surge approaching twenty feet (6.1 meter).