Beyond the growing concerns of rising sea levels, New York City is now grappling with another peril: the gradual sinking of its landmass under the weight of its towering skyscrapers, urban infrastructure, and increasing population.
A recent study published in the journal Earth's Future has revealed that the city is experiencing an average annual subsidence rate of 1 to 2 millimeters.
While subsidence is a natural process that occurs worldwide as the ground settles, this study aimed to investigate how the immense load of the city's structures is making the phenomenon worse.
With over 1 million buildings sprawled across its five boroughs, researchers estimated that the collective weight of these structures amounts to approximately 1.7 trillion tons (1.5 trillion metric tons) of concrete, metal, and glass.
To put it into perspective, this mass is equivalent to about 4,700 Empire State Buildings, exerting immense pressure on the Earth's surface.
The rate of compression varies across different parts of the city. Midtown Manhattan, predominantly built on bedrock, experiences minimal compression.
In contrast, certain areas of Brooklyn, Queens, and downtown Manhattan, situated on less compact soil, are sinking at a faster pace.
While the sinking process is gradual, lead researcher Tom Parsons from the U.S. Geological Survey warns that some parts of the city will inevitably yield to rising sea levels in the future.
Parsons, who specializes in forecasting natural hazards, including ground shifts, acknowledges that the convergence of sinking land and rising water levels is unavoidable.
“It’s inevitable. The ground is going down, and the water’s coming up. At some point, those two levels will meet,” he said.
However, Parsons assures that there is no immediate need for New Yorkers to panic or invest in life-saving equipment.
The study simply highlights the incremental contribution of buildings to the shifting landscape.
The research team employed satellite imaging, data modeling, and extensive mathematical assumptions to arrive at their conclusions.
The transformation of New York into an American Venice, similar to the Italian city sinking into the Adriatic Sea, will take several centuries.
The exact timeline remains uncertain. Nonetheless, certain areas of the city are more vulnerable than others.
Parsons emphasizes the potential risks faced by Manhattan, particularly the southern part with an average elevation of merely 1 to 2 meters (3.2 to 6.5 feet) above sea level. The close proximity to the waterline raises deep concerns regarding future inundation.
