The weight of skyscrapers causes New York to sink by 1-2 mm per year

There are nearly 6,000 skyscrapers rising in the sky in New York, which contribute to the charm of one of the most impressive cities. But the weight of gigantic buildings has a great weight and causes the American city to sink by 1-2 millimeters. Very small scale yes, but long term Earth deformation It could increase the risk of flooding And it is set by comparison Satellite data with subsoil geological models. The study was published in the journal Earth’s Future by a team of experts from the University of Rhode Island led by a geologist Tom Parsons who in the past had already devoted his studies to the “weighing” of cities on the ground.

The researchers calculated the cumulative mass of more than a million buildings in New York City, which turned out to be approx 764 million tons. Then they divided the city into a grid of squares 100 meters on each side and converted the mass of buildings into a downward pressure, taking into account gravity. However, the weight of roads, sidewalks, bridges and railways was not taken into account. This data has been fed into models that reproduce the complex geology of the subsoil, which is mostly composed of Sand, silt, silt deposits and rocky outcrops. Thus, experts were able to confirm that the Big Apple is based on sA fairly diverse substrate that reacts differently to the weight of buildings.

Soils richer in clayey sediments and synthetic fills are more prone to subsidence (i.e., sinking), with an average value of 294 mm measured in lower Manhattan; More loose soil is able to recover after buildings are erected, while the rocky substratum on which many skyscrapers rest does not move much.
By comparing this data with satellite measurements of the Earth’s elevation, the researchers developed a new, more detailed map of New York’s lander. The researchers note that the purpose of the study is to “raise awareness of the fact that every new skyscraper is built in areas Coastal, river, or lakeside areas can contribute to future flood risks“.

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