Rate of Sea Level Rise Demands Action

Unless you are a person who thinks the Apollo Moon landings were faked, perhaps, or that the Earth is flat, it is impossible to argue with NASA’s observations of sea level rise. Satellites tracking the oceans’ surface since 1993 have measured a steady increase, now nearly three and a half inches since Bill Clinton’s first year as president.

Three and a half inches might not sound like much, but in such a short time, the unrelenting rate is extremely alarming for coastal communities. Coastal tide gauges show an even greater rate of rise. As the National Aeronautics and Space Administration explains, sea level rise is caused for the most part by global warming. There are two main factors: higher temperatures that cause seawater to expand and added water from melting ice sheets and glaciers.

Just this week, a new study revealed that the Greenland ice cap is melting about four times faster than previously thought. The volume of water from the loss of approximately 280 billion tons of ice a year, and sometimes as high as 400 billion tons a year, was described by National Geographic as more than enough to cover Florida and New York “hip deep” in meltwater, and then some.

Fortunately, this is not going to happen anytime soon, if only because the world’s oceans are 70 percent greater than the land mass, so the inflow is widely dispersed. But the relentless landward movement of mean high water, though only a few millimeters a year, makes for dramatic changes in places where sea meets land — like Long Island.

What the increase of the past 20 years has meant for coastal erosion depends a lot on location. Nonetheless, anyone who has watched the beaches, particularly on the bay side of Long Island, can report that the destruction of dunes accelerated over that time. One very rough rule of thumb is that for every inch of sea level rise, about a foot of dune or beach is lost. Anecdotally, that appears to be in the ballpark, with houses notably at the brink in Montauk and Amagansett and an intractable problem along the developed Montauk ocean shoreline.

A rising sea has grave implications for waterfront property owners, many of whom bought houses that were built well before the science was understood. It will also challenge local governments, like East Hampton’s, where 1990s-era regulations banning erosion control structures are already being ignored as impractical. 

As individuals, there is little we can do other than reduce our use of fossil fuels and push elected officials to take a firm stand on climate change. Unless far greater action is taken, children born today on Long Island will experience a massive remaking of the landscape from more than two feet of sea level rise by their old age. They will curse our memory if we do not press for everything possible to slow the pace of our rapidly warming planet.