A new study has found that the 28 most populous cities in the United States — including New York, Chicago, Dallas and Denver — are sinking at rates between two and 10 millimeters (0.08 and 0.4 inches) per year.
Using satellite-based radar measurements, a team of researchers from Virginia Polytechnic Institute and State University developed high-resolution maps of sinking land, or subsidence, across major U.S. cities. In each of the 28 cities studied, at least 20% of the city was sinking; in 25 of the cities, at least 65% of the land was sinking.
Cities across Texas show the greatest rates of subsidence, with Houston taking the lead. There, some 40% of the city is sinking at more than 5 millimeters (0.2 inches) per year, while 12% of the city is sinking at 10 millimeters (0.4 inches) per year.
Source: www.space.com
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