It may not be readily apparent to regional residents, but the east coast of the U.S. is sinking. The rate of subsidence in some areas exceeds that of global sea level rise, approaching 5 mm/year. This pace of subsidence is of concern for densely populated areas such as New York City and Baltimore, Maryland, where railways, roadways and other infrastructure are at risk. This spatial map depicts vertical land motion on the east coast. Yellow, orange and red areas denote areas of sinking. Source: Leonard Ohenhen/ PNAS Nexus, Volume 3, Issue 1, 2024This spatial map depicts vertical land motion on the east coast. Yellow, orange and red areas denote areas of sinking. Source: Leonard Ohenhen/ PNAS Nexus, Volume 3, Issue 1, 2024

Maps prepared by researchers from the U.S. Geological Survey and Virginia Tech and published in PNAS Nexus indicate that a large expanse of the U.S. east coast is sinking at least 2 mm per year, with several areas along the mid-Atlantic coast of up to 3,700 km2 (1,400 square miles) being scuttled at a rate of more than 5 mm per year, more than the current 4 mm per year global rate of sea level rise.

Data from space-based radar satellites was used to construct digital terrain maps that show exactly where sinking landscapes present risks to the health of vital infrastructure. Millions of occurrences of land subsidence spanning multiple years were signaled by the imagery, resulting in the development of. high-resolution depictions of the ongoing phenomenon. The observed trends can lead to the undermining of building foundations, damaged roads, and disrupted gas, power and water lines. Coastal flooding may also become more frequent and severe in light of climate change-induced sea level rise.

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