Mexico City is sinking fast enough that scientists say the movement can be detected from space, according to new satellite imagery released this week by NASA. The agency estimated that the ground is dropping by about 9.5 inches (24 centimeters) per year, a pace NASA called among the world’s fastest for large cities.
The metro area, spanning roughly 3,000 square miles (about 7,800 square kilometers) and home to about 22 million people, was built on the bed of an ancient lake, and parts of the region’s layout reflect that history, with downtown areas having once functioned as canals. Today, extensive groundwater pumping and ongoing urban development have reduced the underground water reserves, and that shrinking aquifer has been linked to more than a century of subsidence in parts of the capital, leaving older monuments visibly tilted.
Cabral, who studies geophysics at the National Autonomous University of Mexico, said the problem affects more than just buildings and streets. He told AP that subsidence damages parts of Mexico City’s critical infrastructure, including the subway, drainage system and water systems, and said it is “a very big problem.”
NASA’s estimate of subsidence rates draws on measurements from its NISAR satellite, a joint initiative between NASA and the Indian Space Research Organization. NASA said those measurements were taken between October 2025 and January 2026, when the system captured changes on the Earth’s surface using radar, enabling scientists to track ground movement over time.
In areas highlighted by NASA, the subsidence is happening at about 0.78 inches (2 centimeters) a month on average, including at the Mexico City main airport and the monument commonly known as the Angel of Independence. Taken together, NASA said those rates correspond to an overall yearly drop of about 9.5 inches (24 centimeters), and Cabral said the cumulative decline over less than a century has amounted to more than 39 feet (12 meters).
Rosen, one of the NISAR scientists involved in the effort, said the project’s value goes beyond documenting what is already visible. Rosen told AP that capturing details of Earth from space is “telling us something about what’s actually happening below the surface,” and he said the effort is “basically documentation of all of these changes within a city,” adding that the imagery lets scientists see “the full magnitude of the problem.”
NASA and researchers said the technology could also refine where subsidence is strongest. The team said it hopes to zoom in further over time and eventually generate building-by-building measurements rather than broad maps for larger areas. Broader scientific goals include applying the same approach to track natural disasters, changes along fault lines, and the effects of climate change, including in places such as Antarctica.
For Mexico City, the satellite-based monitoring is also expected to play a role in planning responses, including long-term mitigation efforts. Cabral said the government had largely ignored the subsidence issue for decades beyond stabilizing foundations under monuments such as the Metropolitan Cathedral, where construction began in 1573, but he said that after flare-ups in the water crisis officials have begun to fund more research. He said, “To do long-term mitigation of the situation, the first step is to just understand,” and he said the new satellite data will be key as scientists and officials plan how to address the impacts.