NASA Satellite Maps Mexico City Sinking at Up to 2cm Per Month

A NASA-ISRO satellite has captured unprecedented radar images revealing that parts of Mexico City are sinking at a rate of more than 2 centimeters per month, one of the fastest subsidence rates recorded anywhere. The NISAR mission, which became operational in July 2025, detected the rapid descent in preliminary measurements taken between October 2025 and January 2026 during the dry season.

Areas marked in dark blue on the resulting map, including the site of Benito Juarez International Airport near Lake Nabor Carrillo, show the most pronounced sinking. Yellow and red zones on the map may represent background noise that will decrease as the satellite gathers additional data.

The images confirm that subsidence is highly uneven across the city, a pattern known as differential subsidence that can fracture infrastructure even on the scale of individual buildings or streets. This matches earlier ground-based findings that some neighborhoods drop as much as 50 centimeters per year while others remain nearly stable.

The sinking has been noticeable for more than a century in Mexico City's historic center. The Angel of Independence monument on Paseo de la Reforma, built in 1910, has required 14 additional steps at its base to compensate for the ground dropping around it.

These tilts and shifts affect the entire urban infrastructure. Streets warp, underground metro lines sustain damage, and water distribution and drainage pipes crack. The metropolis of about 22 million people loses an estimated 40 percent of its water supply through leaks in the ageing network.

“Images like this are just the beginning. Since the phenomenon was first documented in 1925, continuous pumping from the underlying aquifer has caused the soil to compact under the weight of the city above. The aquifer still supplies roughly half the capital's water, but extraction now far exceeds natural recharge from rainfall. The water table is dropping about 40 centimeters per year, intensifying the compaction. Climate change has compounded the problem through years of below-average rainfall, raising the prospect of widespread water shortages. Cracked pipes from the sinking create a vicious cycle in which even more water is lost before it reaches homes. A scientist at NASA’s Jet Propulsion Laboratory said the city is subsiding primarily due to groundwater pumping at rates that exceed natural recharge. Stopping the extraction entirely would remove the main water source for millions of residents.”

The satellite uses two synthetic aperture radars operating at different wavelengths and a 12-meter reflector antenna, allowing it to monitor Earth's surface twice every 12 days regardless of cloud cover or vegetation. It can detect changes as small as a few millimeters from week to week.

Researchers at Mexico’s National Autonomous University noted that the NISAR imagery provides a clearer picture of how subsidence varies across different types of land and has reached previously hard-to-study outskirts. The data extends beyond Mexico City to potential uses in tracking volcanic deformation, earthquake-related shifts, landslides, glacier movement, soil moisture, coastal flooding and agricultural changes.

"NISAR will see any change big or small that happens on Earth from week to week. No other imaging mission can claim this," a NASA Jet Propulsion Laboratory scientist told reporters. Project managers described Mexico City as a known hotspot and said the new measurements align with expectations for the satellite's performance.

Limited efforts have been made to address the sinking beyond reinforcing historic building foundations. Officials acknowledge that halting subsidence would require sharply reducing groundwater extraction, a step that carries immediate practical difficulties for water supply.

The fresh satellite data is expected to focus greater attention on the long-term challenge facing the Mexican capital.