Nisar Satellite Reveals Mexico City Sinking Over 2 cm Each Month at Airport

TL;DR: NASA’s Nisar satellite finds parts of Mexico City, including the main airport, sinking at more than 2 cm per month, with the Angel of Independence monument gaining 14 extra steps as the ground drops.

Mexico City sits on an ancient lakebed of soft clay. The city’s foundations rest on sediments that were once underwater.

For over a century, residents have pumped groundwater to meet demand, causing the clay to compact and the surface to lower.

Historic landmarks in the Zócalo already tilt, and the sinking now disrupts water pipes, roads and the metro system.

The Nisar mission, a joint NASA‑ISRO L‑band synthetic‑aperture radar satellite, scans the planet weekly.

Its radar penetrates clouds and vegetation, measuring surface height changes to millimetre precision.

Marin Govorčin of NASA’s Jet Propulsion Laboratory says Nisar can detect any Earth‑surface shift from week to week, a capability no other imaging mission matches.

Data from Nisar show the airport area subsiding at over 2 cm each month, one of the fastest rates recorded globally.

Near the Angel of Independence on Paseo de la Reforma, the monument’s base has had 14 steps added since 1910 to compensate for sinking ground.

The underlying aquifer’s water table is falling about 40 cm per year, and roughly 40 % of the capital’s water is lost through leaks from aging pipes cracked by the sinking.

Ongoing subsidence strains infrastructure, raises flood risk and threatens water security for the city’s 22 million residents.

Experts warn that stopping the decline would require halting groundwater extraction, which would cut off half of the city’s supply.

The detailed, weekly Nisar maps give planners a tool to target reinforcement efforts and assess the effectiveness of any recharge or conservation measures. Scientists will watch whether upcoming water‑recharge policies can slow the subsidence trend.