Study Finds Subsidence Doubles Coastal Sea-Level Rise to 6 mm a Year for 71% of People
Updated
Updated · Nature.com · May 16
Study Finds Subsidence Doubles Coastal Sea-Level Rise to 6 mm a Year for 71% of People
2 articles · Updated · Nature.com · May 16
A new global analysis estimates coastal populations experienced 6 mm a year of relative sea-level rise in 1995-2020—about twice climate-driven absolute sea-level rise—because sinking land added roughly 2.8 mm annually.
Nearly 71% of people in low-elevation coastal zones live in subsiding areas, and 43% face subsidence of at least 2 mm a year, with hotspots including Jakarta, Tianjin, Bangkok, Lagos and major deltas.
The study stitched together GNSS, tide gauges, satellite altimetry and InSAR data, extending direct measurements to almost 65% of the global coastal population and capturing small-scale sinking missed by earlier global estimates.
Population-weighted sea-level rise was nearly three times the coastal-length average of 2.1 mm a year, showing densely populated cities and deltas bear much higher exposure than global coastline averages suggest.
Researchers said current projections and risk assessments can still miss or understate local land motion, especially in Asia and Africa, and called for denser open monitoring networks and updated adaptation planning.
Why are coastal cities sinking faster than seas are rising, and is the solution right beneath our feet?
Millions more people are at risk from rising seas than we thought. Why were previous estimates so dangerously wrong?
Sinking Shores: How 43% of the World’s Coastal Population Faces Rapid Subsidence and Rising Seas
Overview
A major study published in 2026 reveals that accelerated land subsidence, or sinking, is a critical and often overlooked threat to coastal communities worldwide. Strikingly, 43% of people living in low-lying coastal areas are in regions sinking at least 2 millimeters per year. This widespread land sinking makes the dangers of climate-driven sea-level rise much worse, creating an urgent need for adaptation. Because the rate of sinking is more than half the current rate of global sea-level rise, many communities face a much higher risk of flooding, saltwater intrusion, and permanent inundation than global averages suggest.