For their new study, scientists first calculated the total mass of New York’s 1-million-plus buildings: 764,000,000,000 kilogrammes or 1.68 trillion pounds
New York is sinking fast and new research reveals that real estate developers’ ‘bigger is better’ ethos is the cause.
A team from the US Geological Survey and the University of Rhode Island found that the weight of the city’s giant skyscrapers is causing the five boroughs to sink one-to-two millimetres yearly.
The team analysed the weight of 1,084,954 buildings constructed across a 302-square-mile city, including over 6,000 skyrises – 247 of which are skyscrapers over 150 feet tall. As these behemoths push the ground beneath them closer and closer to sea level, climate change is raising the ocean to meet them. While a few millimetres might not sound catastrophic, some parts of the city are subsiding much faster, keeping pace with the fastest rates that Earth’s tectonic plates are known to move.
‘It can be exacerbated with storm-forcing,’ geologist and study co-author Tom Parsons of the US Geological Survey told Dailymail.com. ‘Obviously, we’ve had some events in New York City with hurricanes coming in.’
A sinking city and rising ocean tides, Parsons said, will put New York at greater risk of becoming inundated with flood waters the next time a hurricane like Sandy or Ida rages up the Atlantic coast.
‘That’s where a lot of the inundation risk comes from,’ Parsons said. ‘Not necessarily that the island will be completely submerged – at least not anytime soon.
‘But when you have these extreme events, you can start seeing inundation.’ Parsons and his colleagues said that they are, in fact, likely underestimating the severity of the situation, as their research did not consider the burden of other heavy features like asphalt roads, concrete sidewalks, railways, or the rest of New York City’s infrastructure.
Last year, some of the study’s University of Rhode Island co-authors listed the Big Apple alongside 98 other coastal cities around the world that are also sinking under the weight of their majestic skylines.
In most of the cities they surveyed, the land below is receding faster than sea levels are rising due to climate change – the dangerous combination that threatens residents with greater flood risks sooner than predicted by today’s climate models.
For this new study, the scientists first calculated the total mass of New York’s one-million-plus buildings: 764,000,000,000 kilogrammes or 1.68 trillion pounds.
By examining all that weight, parcelled across a grid of 100-by-100-meter squares, the team was able to convert building mass into a clear measurement of the downward force pressing down on the bedrock below the city.
They then compared this work against satellite imagery capable of measuring changes in land surface height, mapping those readings over their citywide estimates to vet their model against real-world data.
Another absent factor, they said, that could even more rapidly worsen the problem is the draining and pumping of groundwater, which could essentially assist the pressure coming down from the buildings to further compact the dirt and rock below. ‘The point of the paper,’ writes Parsons at USGS and his colleagues at the University of Rhode Island, ‘is to raise awareness that every additional high-rise building constructed at coastal, river, or lakefront settings could contribute to future flood risk.’