New Orleans: A Natural or Manmade Disaster?

Natural disasters like hurricanes do not seem to be, at first glance, of our own doing. Much of the shock of the event, I think, has been connected to the fumbled response and helplessness of the people left behind in the city. However, now that the shock of Hurricane Katrina is passing -- at least for everyone watching -- there seem to be a lot of thoughtful articles on the complex interaction between the city of New Orleans, its infrastructure, and the alteration of the natural geography of the area.

Flood Control Systems
The most obvious feature of New Orleans is that it lies below sea level, nominally defended by a complex system of levees, dikes, and canals. For those playing catch-up on the news, there is a nice general introduction at the Guardian. There are also excellent interactive graphics, updated daily, at the New York Times and Washington Post. The New York Times also recounts how the system and city came to exist in its precarious location last week, surveys a variety of flood control and flood protection systems, mostly in Europe, and follows scientists as they study the effects of the storm.

A lot of the infrastructure that ultimately failed was built in the name of flood control, but because water shapes our daily lives so powerfully, the Army Corps of Engineers' role as a water management agency has become more complex. There is a lucid description of the Army Corps' history at CounterPunch (though I find this article concludes oddly when abruptly turns from history into current politics). Beyond the immediate outcry over the Bush administration's diversion of funding of flood control projects, what should the role of the Army Corps be? There are a couple of National Academy reports on the Corps' role here. Maybe it's a bit early, but the next logical question to me is: what's the long-term future of this system?

Natural Protection from Storms
Storm systems such as hurricanes gain strength in the open ocean. The Guardian has a nice interactive graphic on how hurricanes are formed here. The Wall Street Journal science writer points out that many aspects of the storm damage are human-caused here:

More than a million acres -- 1,900 square miles -- of Louisiana's coastal wetlands have been lost to development and flood controls since the 1930s, along with barrier islands and stands of coastal forest. Louisiana continues to lose about 25 square miles of coastal area each year. These natural barriers could have absorbed some energy and water from Katrina's storm surge and mitigated the hurricane's force; studies estimate that storm surges rise by about a foot for each square mile of wetlands lost.

The Worldwatch Institute also finds that economic losses continue to increase with the frequency of extreme weather events:

In 2004, weather-related disasters caused nearly $105 billion in economic losses (in 2003 dollars)—almost twice the total in 2003. Roughly 12,000 weather-related disasters since 1980 have caused just over 618,200 fatalities and cost a total of 1.3 trillion. Average annual economic losses from such events have risen from $26 billion in the 1980s to $67 billion over the last decade. Average annual fatalities due to weather, meanwhile, jumped from 22,000 in the 1980s to 33,000 in the 1990s.

The state of Louisiana and the federal government came up with a coastal restoration and protection plan in 1998 called Coast 2050, which restores and/or mimics the functioning of the natural ecosystems that previously protected the shore (though perhaps not beachfront properties). The Louisiana Coastal Area Ecosystem Restoration Project has a lot of statistics and maps on the economic and ecological value of the coast. There is a comprehensive look at coastal restoration from the National Oceanic and Atmospheric Administration here. The question, is of course, how to pay for it, and the state and federal government were wrangling over the plan as recently as last week before the storm here.

Extreme Weather Events
RealClimate addresses whether hurricanes and global warming are connected directly here. Grist has already started covering the coverage of climate change and Katrina here, with a number of well-known science journalists pitching in their views. WorldChanging is angry, feisty, and declares Katrina to be both a watershed and harbinger of things to come here:

This tragedy was no "Act of God" -- some utterly unforeseen tragedy about which nothing could be done. This was a completely predictable (indeed, predicted) unnatural disaster. For years, scientists and engineers have been warning of the danger New Orleans was in. For years, nothing was done.... We also know that Katrina was just a foretaste of what we should expect in the coming years. We are changing the weather with the pollution we spew from tailpipes and smokestacks, and the bill for that irresponsibility is starting to come due.

Technorati Tags: cities, ecosystems, New Orleans, wetlands