Climate scientists are already We know that the east coast of the United States could see about a foot of sea level rise by 2050, which in itself would be devastating. But they’re just beginning to thoroughly measure the “hidden vulnerabilities” that make things even worse. SinkThis is a phenomenon known as land subsidence and could make sea level rise even more dangerous for both humans and coastal ecosystems.
New research published in the journal Nature Communications The Atlantic coast, home to more than a third of the US population, is losing several millimeters per year. In Charleston, South Carolina and the Chesapeake Bay, it is up to 5 millimeters (one-fifth of an inch). Some parts of Delaware have twice as many as her.
An annual sea level rise of 5 mm along the coastline plus 5 mm of subsidence there effectively corresponds to a relative sea level rise of 10 mm. Cities on the Atlantic coast are already suffering from constant flooding, and flooding will get worse as cities sink while sea levels rise. However, such high-resolution subsidence data have not yet been considered for coastal hazard assessments. “What we want to do here is really raise awareness about this missing element. is much worse,” says Manoucher Sirzaei. He is an environmental security expert at Virginia Tech and co-author of the new paper.
A major cause of dramatic land subsidence is over-extraction of groundwater from it. This causes the terrain to collapse like an empty plastic bottle. In San Jose, California, this lowered elevation by as much as 12 feet. A combination of sea-level rise and subsidence could inundate up to 165 square miles of Bay Area coastline by 2100, according to Shirzaei’s previous research. Parts of Jakarta are sinking 10 inches each year, forcing Indonesia to move its capital elsewhere. Drilling for oil also causes land subsidence, which is a serious problem especially in the Houston-Galveston area. Landfills and sediments along the coastline can also subside over time.
Scientists knew that the U.S. coastline was sinking, but there wasn’t much data showing regional differences in the rate of subsidence. Sinking varies greatly even over short distances. For the new paper, Shirzaei and lead author Leonard Ohenhen, also an environmental security expert at Virginia Tech, used data from highly sensitive satellites that fired radar signals toward Earth to determine what coastal deformation was identified by analyzing how the They did this along her 3,500 kilometers (2,200 miles) of the Atlantic coast for several years from 2007 to 2020.
Researchers have found particularly severe subsidence in agricultural areas where groundwater is extracted to feed crops. We also found that most Atlantic cities, including Boston and New York City, experienced subsidence of 3 mm or more per year. Ground infrastructure such as buildings and roads, as well as buried pipes and cables, become unstable as altitude decreases.
