The geology of impermanence

A few months ago, I saw a post about Cape Cod on NASA’s Earth Observatory. The post showed a pair of satellite images of Cape Cod separated by nearly 30 years, which made it quite clear that the shoreline is a dynamic thing.

After discussing the mechanisms that are causing barrier islands to move around and split up, the article quoted Robert Oldale, a coastal geologist with the U.S. Geological Survey. Oldale pointed out that although erosion is often seen as a threat to be controlled if possible, it’s a well-established natural process that allows the cape to accommodate itself to increases in sea level. He concludes by saying:

Erosion is only a peril to property. If we build on the shore, we must accept the fact that sooner or later coastal erosion will take the property away.

Could any parable have delivered a better punch line? It’s not just coastal properties or even physical buildings that will eventually be gone. Whatever structures we build, physically or figuratively, we must accept the fact that sooner or later, natural processes will take them away. I don’t know whether Oldale intended any deeper meaning, but he seemed to capture well the tension between the human desire for permanence and the fact that we live in a profoundly impermanent world.