By Sarah Do Couto- New York City‘s skyscraper skyline is iconic, but it may be causing the Big Apple to sink, a new study suggests.
According to research published by the scientific journal Earth’s Future, the cumulative 1.68 trillion-pound weight of New York City’s buildings is causing the city to sink about one to two millimetres per year on average.
The “subsidence rate” — the scientific term for the speed of sinking — was observed by three University of Rhode Island oceanologists and a researcher from the U.S. Geological Survey. In order to measure the rate of New York City’s apparent sinking, researchers created geographic models to exhibit the downward pressure of heavy buildings on the bedrock, clay, sand and silt underneath some of the region.
Researchers claimed Lower Manhattan – a veritable concrete jungle – is at a greater risk of sinking than most other areas of the city. As is, much of Lower Manhattan sits only one to two meters above the current sea level.
Parts of Brooklyn and Queens are also experiencing higher subsidence rates than other parts of New York City.
Though a one or two millimetre decline per year may not seem like much, researchers warned the city’s shift worsens the threat of flooding in the region, especially amid already rising sea levels.
“New York faces significant challenges from flood hazard; the threat of sea level rise is 3 to 4 times higher than the global average along the Atlantic coast of North America,” researchers wrote. “A deeply concentrated population of 8.4 million people faces varying degrees of hazard from inundation in New York City.”
New York City has already faced flooding in the past, namely from Hurricane Sandy in 2012 and Hurricane Ida in 2021 — the latter of which led to the drowningdeaths of several people.
The study claimed these events, and future flooding, could negatively impact the structural integrity of New York City’s buildings. When salt water repeatedly reaches building foundations, it can corrode the reinforced steel and chemically weaken concrete.
About 90 per cent of the 67,400 buildings in the expanded post-Hurricane-Sandy flood risk areas in the city “have not been built to floodplain standards,” researchers claimed.
“It’s not something to panic about immediately but there’s this ongoing process that increases the risk of inundation from flooding,” Tom Parsons, a geophysicist at the US Geological Survey and lead researcher of the study, told The Guardian.
He continued: “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.”
New York City is not the only coastal city at risk of flooding. The study claimed the presence of greenhouse gases in Earth’s atmosphere “appears to be reducing the natural wind shear barrier along the US East Coast, which will allow more frequent high intensity hurricane events in the coming decades.” This includes cities like Boston, Mass., Charlston, S.C. and Atlantic City, N.J.
“New York is emblematic of growing coastal cities all over the world that are observed to be subsiding, meaning there is a shared global challenge of mitigation against a growing inundation hazard,” researchers wrote.
As of now, it is unclear how to stop New York from sinking, or how to prevent flood risks in the region. Researchers hope, however, that their study will push for more research into creative solutions to fight the effects of climate change on densely populated, urban areas. (Global News).
