A new study has pinpointed just how much New York City is sinking, and which hotspots are most affected. As sea levels are rising, the Big Apple is sinking at a subsidence rate of about 1.6 millimeters per year, according to the study by NASA’s Jet Propulsion Laboratory and Rutgers’ Department of Earth and Planetary Sciences. The cause is largely glacial isostatic adjustment, a geological process in which land that is suppressed under huge ice caps rises up as the ice melts then slowly reverts back to its original levels. The study found that the most rapid change is occurring where landfill sites once where, primarily LaGuardia Airport in Queens and the nearby Arthur Ashe Stadium, the iconic home of the U.S. Open. In fact, Arthur Ashe Stadium’s rooftop is made out of lightweight cloth for that very reason, one of the study’s authors told ABC7. Outside the city, Highway 440 and Interstate 78 are sinking faster than other areas, the study found.