Managed retreat is a term that I have been encountering more and more frequently in the course of my work over the last few years. It is the idea that in response to sea-level rise, humans will be forced to move away from coastlines, and this can happen in a chaotic way, or a managed way, but it will happen.
Imperial Beach, CA (Photo by JC Monge).
As the atmosphere and oceans warm, sea-level will rise. This is happening now, with a rise of about a half-an-inch each decade, and this number will likely increase over time. Globally, sea-level is predicted to rise by 1.6 to 6.5 feet in the next 100 years. This does not sound like much to a lot of people. What people forget to think about is that the sea does not stay still. Storm surges and king tides account for a large portion of the damage that seas cause to cities. These surges and tides will be much more severe if the sea they are starting from is one to 6 feet higher than it is right now. Imagine some of the footage we have all seen from hurricanes as they sweep across Florida or Texas or Puerto Rice. In those clips reporters are clad in rain gear with trees bending wildly behind them as the wind and rain hammers away. Now add a extra 6 vertical feet of water! The effects then will be much more disastrous than the effects now, and now they are bad enough.
And these effects will be felt all around the world. A large percentage of people around the globe live near coasts. So raising seas will effect a huge number of people. This has the potential to cause social chaos as people struggle to move inland in disorderly and inefficient ways.
To address this impending threat, some communities, cities, and even states are beginning to consider how to move away from the sea.
It is a herculean problem. How can we move a whole city even a short distance? Even a small city is just not portable. However, they are going to have to be, and the more we as a society can think about how to accomplish these moves, the better off we will all be when they have to happen. And that is where managed retreat comes in.
The High Country News published an article on how the small city of Imperial Beach in southern California is starting to think about managed retreat. Even for this small city to move a few blocks away from the ocean will be a huge undertaking. The article is a sobering read, but well worth it since it is something that is gong to effect every person on earth who is alive in 2050 or 2100.
abirdingnaturalist 