But American cities—along with cities around the world—are facing yet another problem that’s only exacerbating this concerning side effect of climate change: They’re sinking. sinking) rate of 28 major U.S. cities across the country and found that at least 20 percent of the urban area of all of the cities was sinking to some degree. In 25 of those 28 cities, more than 65 percent of the land area was sinking to varying degrees. Related Story San Francisco Skyscraper Is Leaning—And SinkingObviously, the image of cities slowly sinking paints a picture of places like Houston, New York, and L.A. simply slipping into the sea. The leading cause of subsidence is groundwater extraction, which eventually leads to compaction of soil and sediments and—you guessed it—the net result of slowly sinking land.