Satellites Reveal San Francisco's Millennium Tower Skyscraper Is Sinking
European Space Agency's released data from new satellites confirming the sinking of the San Francisco's 58-story Millennium Tower. The Sentinel-1 satellites detected that the said tower is sinking by a few centimeters every year. A study by ESA indicates that studying the city is helping scientists to improve the monitoring of urban ground movements, particularly for subsidence hot spots in Europe.
The Millenium Tower skyscraper is located on 301 Mission Street in the South of Market district in San Francisco. Its construction was completed in 2009. It is considered the tallest building in San Francisco and a home of some famous celebrities like Joe Montana and Hunter Pence.
In the study, the scientists used multiple radar scans from the Copernicus Sentinel-1 twin satellites to identify subtle surface changes deep down the area. This technique even reflects the radar beam. ESA and the team of researchers from North, PPO.labs and Geological Survey of Norway also mapped other areas in San Francisco Bay Area. They detected an uplift of the land around the city of Pleasanton probably due to replenishment of groundwater following a four-year drought that ended in 2015.
John Dehls from the Geological Survey of Norway explained that the experience and knowledge gained within the ESA's Scientific Exploitation of Operational Missions program give them strong confidence that Sentine-1 satellites will be a highly versatile and reliable platform for operational deformation monitoring in Norway and worldwide. It is reported that European cities are also undergoing the same sinking. This makes the San Francisco study helps the scientists. One example of this is the area around Oslo's train station in Norway, which is a reclaimed land, according to Phys.Org.
Dag Anders Moldestad from the Norwegian Space Centre explained that in Norway, they have already initiated a framework project to provide nationwide basic deformation products to the public, with a free and open data policy. He further explained that many other countries in Europe are also working toward setting up similar devices.