The Big Apple is sinking under its own weight, posing a worsening flood risk to the city, according to a new study by researchers from the University of Rhode Island Graduate School of Oceanography.
Already faced with intensifying extreme weather and an increasing threat of flooding due to sea level rise, New York City is gradually sinking at an average of about one to two millimeters annually, with some areas subsiding twice that fast, the study said.
Since 1950, New York City has seen its surrounding water levels rise by almost nine inches, according to Sea level rise.org.
The NOAA Climate Program Office said major flood events could happen three to four times as often from 2054 to 2079, according to a new National Oceanic and Atmospheric Administration (NOAA) Research-funded study, which means residents of Gotham might face more intense flooding in the future.
“It’s not something to panic about immediately but there’s this ongoing process that increases the risk of inundation from flooding,” said Tom Parsons, a geophysicist with the U.S. Geological Survey and the study’s lead author, as The Guardian reported. “The softer the soil, the more compression there is from the buildings. It wasn’t a mistake to build such large buildings in New York but we’ve just got to keep in mind every time you build something there you push down the ground a little bit more.”
The researchers point out that New York isn’t the only city that will be facing increasing risks, as coastal cities all over the planet face more intense hurricanes, subsidence and sea level rise that are the result of human activities that led to the climate crisis.
The study, “The Weight of New York City: Possible Contributions to Subsidence From Anthropogenic Sources,” was published in the journal Earth’s Future.
In the study, the scientists calculated the magnitude of the city’s structures — including the iconic emblems of the famous skyline, the Empire State Building and the Chrysler Building — and found that they weigh a total of 1.68 trillion pounds, the mass of around 140 million elephants.
Many of the city’s largest buildings sit on schist and other types of solid bedrock, but others have been built upon softer mixtures of clays and sands, which contributes to the sinking effect, reported The Guardian.
“Major cities around the world are expected to grow disproportionately relative to rural areas, with a projected 70% of the world’s population living in cities by 2050. Major cities on every continent except Antarctica are observed to be subsiding, and the issue may be worsened as populations grow. Increasing urbanization will likely exacerbate subsidence by groundwater extraction and/or construction density, which combined with accelerating sea level rise implies a growing flood hazard in coastal cities. As these trends continue it will be important to be mindful of accompanying mitigation strategies against inundation in growing coastal cities,” the authors of the study wrote.