Without its skyscrapers, New York wouldn't really be New York. But these defining structures that are so characteristic of the city, these buildings that tower over the neighbourhoods and its inhabitants are playing a role in pushing it a little further into the ground
New York City is under threat from rising ocean level and the increase in extreme weather events. But another factor is also a contributor to worsening the phenomenon: the titanic weight of its buildings.
Without its skyscrapers, New York wouldn't really be New York. But these defining structures that are so characteristic of the city, these buildings that tower over the neighborhoods and its inhabitants are playing a role in pushing it a little further into the ground. And the risk appears to be particularly high on the island of Manhattan, home to NY's most emblematic buildings such as the Empire State Building and the Chrysler Building. These are the findings of a study published in early May in the journal Earth's Future. To reach this conclusion, American researchers from the University of Rhode Island calculated the mass of all the buildings in the five boroughs of New York City (a total of 1,084,954 buildings). Verdict: 1.68 trillion pounds or 764 million metric tons!
The researchers then modeled settlement caused by the pressure of these buildings, depending on the nature of the soils supporting them. "We estimate settlement for surface conditions ranging from bedrock to soft soils to account for uncertainties in localized geology and foundation styles," say the authors of the work. Presented in the form of satellite images, the data collected in this research shows continued subsidence—sinking—of New York City averaging about 1 to 2 mm per year.
"New York City is emblematic of growing coastal cities around the world that are observed to be subsiding, meaning there is a shared global challenge of mitigation against a growing inundation hazard," the researchers conclude. The issue is all the more crucial because the Big Apple, which is home to more than eight million people, is also in danger of disappearing due to rising water levels as well as an increase in hurricanes and storms due to climate change. And it's far from the only city at risk of being swallowed up by the waters.