Scientists predicted catastrophe for New York
New York is sinking at a rate of several millimetres per year because of sky-high buildings, and subsidence threatens another 99 large megacities, RIA Novosti reports
Scientists from the US Geological Survey and the University of Rhode Island analysed data from satellite altimetry and ground-based geodetic observations over the past few years. They came to the conclusion that the Earth's surface in New York is sinking by an average of one to two millimetres per year. The simulation results showed that this is due to the subsidence of soils under the weight of buildings and infrastructure facilities.
Previously, forecast flood models took into account only the rise in global sea level, which makes 3-3.5 millimetres per year. Subsidence of soils can become an equally important factor.
The researchers calculated the total weight of New York buildings: almost 770m tonnes – not taking into account roads, railways, sidewalks, bridges and other infrastructure. They then divided the city into 100x100m cells, calculated the pressure of buildings in each of them and compared it with the type of soil. It appeared that, in some areas – such as Lower Manhattan, Brooklyn and Queens – where skyscrapers stand along the coastline on sand and clay, the rate of subsidence reaches six millimetres per year.
Such movements can create a serious problem for the largest metropolis in the United States. Firstly, skyscrapers simply collapse because of this displacement and penetration of salt water into the base. Secondly, the risk of flooding is increasing. A significant part of Lower Manhattan is only one to two metres above sea level. The hurricanes of 2012 and 2021 showed how quickly this area can be completely under water.
"Every new high-rise building erected on the coast increases the risk of subsidence and flooding in the future. We should ask ourselves more often what the consequences of such construction are," Tom Parsons, from the US Geological Survey, said.
