New study shows that New York City is sinking in part because of the huge weight of its skyscrapers. This makes the threat of flooding from rising seas even worse for the city. As the saying goes, “The Big Apple never sleeps,” but it does sink. According to experts, New York City sinks by about 1-2 mm each year on average, and some parts of the city sink at twice this rate.
This sinking is making the effects of sea level rise worse. The rise is happening about twice as fast as the global average because the world’s glaciers are melting and seawater is rising because of global warming. Since 1950, the water around New York City has risen about 9 inches (22 cm). By the end of the century, big storms could cause up to four times as many flooding events as they do now, because climate change is making hurricanes stronger and sea level rise.
Within New York City, 8.4 million people live in areas that are very close to each other and face different levels of risk from flooding, according to a new study released in the journal Earth’s Future.
They also said that as the climate problem gets worse, many other coastal cities around the world will face the same risks as New York City. “The mix of tectonic and human-caused subsidence, rising sea levels, and stronger hurricanes suggests that the problem along the coast and rivers is getting worse,” they wrote.
The sheer amount of built infrastructure in New York City is making this trend stronger. The researchers found that the city’s buildings, like the famous Empire State Building and Chrysler Building, weigh a total of 1.68tn lbs, which is about the same as 140 million elephants.
This huge weight is pressing down on a mess of different objects on the ground in New York City. Many of the tallest buildings are built on solid bedrock like schist, but other sands and clays have been built on top of them. This makes the ground sink even more, which happens naturally along much of the east coast of the US as the land responds to the melting of huge glaciers after the last ice age.
Tom Parsons, a geophysicist at the US Geological Survey and the leader of the new study, said, “It’s not something to worry about right now, but there’s this ongoing process that raises the risk of flooding.” “There is more pressure from the buildings when the ground is soft.” It wasn’t a bad idea to build such big buildings in New York, but we should remember that every time something is built there, the ground sinks a little more.
In 2012, Hurricane Sandy hit New York. It flooded parts of the subway and did a lot of damage, including cutting power to a lot of people. After that, Hurricane Ida flooded parts of the city in 2021, killing several. Scientists say that both events were made worse by the warming of the Earth.
Parsons said that coastal towns like New York “need to start making plans for this.” If you are exposed to salt water over and over again, it can rust steel and make buildings less stable, which is obviously not what you want. People also die in floods, which is probably the biggest worry.