New York City sinks a little under the weight of its buildings each year — making it more vulnerable to the effects of flooding, which have been exacerbated with climate change.
That’s the conclusion of a new study published in Earth’s Future Journal.
The study, signed by three University of Rhode Island oceanographers and a US Geological Survey geophysicist, shows that New York is sinking at a rate of 1 to 2 millimeters per year, largely due to the weight of the skyscrapers that dominate the sea city , including giants like the Empire State Building and the Chrysler Building.
According to the study, there are more than 1 million buildings in the city with a combined weight of 1.7 trillion pounds (765 million tons). To give you an idea, that’s the weight of 140 million elephants. (Fun fact: An adult elephant weighs between 2 and 7 tons. Here we use a 5.4 ton elephant as the base.)
According to the study, parts of Lower Manhattan, Brooklyn, Queens and Long Island showed clear signs of subsidence the technical term for “subsidence” of the ground.
“There’s no reason to panic immediately, but there is this ongoing process that increases the risk of flooding,” Tom Parsons, the geophysicist who led the study, told The Guardian.
“The softer the ground, the more compression the buildings have. It wasn’t a mistake to build such huge buildings in New York, but we have to remember that every time you build something there, you put a little more strain on the ground.”
The city has already suffered from natural disasters. In 2012, Hurricane Sandy hit the city, flooding parts of the subway and causing extensive damage, including power outages. In 2021, another hurricane, Ida, also inundated several neighborhoods.
For Parsons, New York and other coastal cities need to “plan for it.”
“Repeated exposure to seawater can corrode steel and destabilize buildings, which of course nobody wants. Floods also kill people, which is the biggest concern.”
The sinking of New York is accompanied by an accelerated rise in sea levels. Since 1950, the water around the city has risen by 22 centimeters.
Scientists estimate that by the end of the century, major storm surges could be four times more common than they are today, due to a combination of rising sea levels and climatefueled hurricanes.
Peter Arbex