US East Coast Cities Are Sinking; Satellite Images Reveal Extent

Various satellites have gathered images that reveal that major cities and population centers along the US East Coast are actually sinking.

Subsidence: Land Sinking

The phenomenon of subsidence, or land sinking, is quite dangerous, as it can undermine building foundations and potentially lead to collapse. Moreover, subsidence can also cause damage to water and gas lines.

When mixed with the rising sea levels due to climate change driven by humans, land sinking in coastal areas can increase flooding risks and worsen the damage that subsequently follows.

Sinking Cities in US East Coast

Some of the hardest-hit areas include Long Island, New York City, Virginia Beach, Norfolk, and Baltimore. These areas are going through rapid subsidence next to regions that are slower-sinking and even stable land patches.

This threatens infrastructure, including building foundations, roads, airport runways, rail lines, and pipelines.

According to the new research done by Virginia Tech and the USGS (US Geological Survey), some regions within the East Coast are sinking as fast as five millimeters per year. This is a subsidence rate at the Atlantic Ocean's edge that outstrips the global rise of sea levels. The findings were noted in the "Slowly but surely: Exposure of communities and infrastructure to subsidence on the US east coast" study.

Leanard Ohenhen, the study's lead author and a graduate student from the Virginia Tech Earth Observation and Innovation Lab, explains that unmitigated and continuous land sinking across the US East Coast should raise concerns. This is particularly true in areas with high property density and population, as well as historical complacency when it comes to the maintenance of infrastructure.

The team of Ohenhen gathered huge quantities of data from radar satellites based in space to construct digital maps of the area. They then gauged millions of subsidence events throughout several years. They followed up by constructing some of the earlier high-resolution shots of sinking land.

The map of the team revealed that a significant number of areas within the US East Coast are sinking by at least 2 millimeters each year. On top of this, the researchers also discovered areas on the mid-Atlantic coast that are sinking by 5 millimeters or more per year.

In comparison, the global rising rate of sea levels at present is roughly four millimeters per year.

Professor Manoochehry Shirzaei, an associate of the Virginia Tech Earth Observation and Innovation Lab who participated in the efforts, explains that they gauged land sinking rates of two millimeters per year that impact over two million individuals and 800,000 properties within the East Coast. Through the study, the researchers were able to stress how land sinking is not an intangible threat. While the process may take place gradually, its effects are real.

Ohenhen further notes that the issue with subsidence is not just the sinking of the land, but that subsidence hotspots are taking place around infrastructure concentrations and population hubs.

Patrick Barnard, a co-author of the study and a research geologist of the USGS, explains that the information is crucial and that no one else is offering it.