When New York sinks
Is New York sinking under the weight of its skyscrapers? This is the scary picture that emerges from recent research, although the estimate is only 1 to 2 millimeters per year.
The difference depends on the ground on which the buildings rest. Unsurprisingly, the more clayey it is, the greater the “ compression ” caused by buildings, unlike rocky basements.
It's not even a phenomenon unique to New York: In most major coastal cities, geologists have long noted “settlement”, which results in part from the fact that groundwater is gradually drained outward and the soil compacts. But New York is an island, which means that there is water infiltrating from all sides: even at the rate of one or two millimeters a year, this could cause problems in the future. closer due to sea level rise.
According to data from the US Oceans and Atmospheric Agency (NOAA), the water level around the island has risen 22 centimeters since 1950, and major flooding caused by storms could be four times more frequentd end of the century.
New York being, in addition, famous for its skyscrapers, this is what gave the idea to three American oceanographers and a geologist to estimate their weight—842 tons—and to use that data to assess how much of a difference that weight could make to “sag”.
Their research was published May 8 in the journal< em>Earth's Future. Interviewed in The Guardian, the main researcher, geologist Tom Parsons, however, does not speak of the construction of these massive buildings as a “mistake”.
“ You just have to keep in mind that each time you build something there, you push the ground down a little bit more ”. New York has in common with all other major coastal cities to have to prepare for it: it will be more often exposed to seawater, which causes rust and can destabilize buildings.