Second Coming of Atlantis
This morning on NPR, they ran a story about how New Orleans is sinking, and it has been for over a century. This is really more Cailin’s field of expertise (fluvial geomorphology) but I’ll try to give that layman’s summary:
Basically New Orleans is built on sediment. LOTS of sediment. And the deeper layers of the sediment are compacting and eroding as groundwater flows through it over time. They said that over the past century, New Orleans has sunken about two feet, but that the rate of the erosion has been accellerating, and the city may sink as much as a yard or a meter over the next century. Obviously that’s not good, since much of the city is already below sea level.
The natural course of things, had people not interfered and dammed and leveed the river, is that the Mighty Miss would overflow its banks, bringing with it a huge slug of sediment to replenish the deeper layers that are constantly eroding. The sand and soil would get layed over the top of the land, the relative height of the land would stay about the same, and, most importantly, it would stay above sea level. But once we began to build on top of this land, we didn’t want it to flood, so we protected our property with the levees and dams. And now we are witnessing why that isn’t sustainable in the long-term.
Now this isn’t new information. People have known this was happening for a long time, and some people even wrote about it a year ago in this little magazine, called National Geographic. In fact the opening paragraphs of this story are so eery, they may as well have been written by Nostradamus.
But the truth is that the story was written by well-informed scientists who have been studying the problem for years. After the hubbub about who knew what and when regarding the September 11, 2001, terrorist attacks on the World Trade Center it will be interesting to watch the finger-pointing and the “special investigations” (Ooooo!) and see who ends up the scapegoat for this horrible natural and unnatural disaster.
Personally, I don’t think it matters much why or how it happened that “better” plans weren’t made for this hurricane, or more proactive steps weren’t taken to stop the hijackers four years ago. What matters to me is what plans we are going to make for the next potential hurricane or for whatever psychopaths might decide to do in the future.
To (roughly) quote a good movie I saw recently, “We can’t change the past, and we don’t know what’s going to happen in the future. All we have is now.”
