What lies beneath Europe’s sinking ground?

Subsidence is the downward movement of the ground and is widespread across Europe. Its causes and effects vary greatly depending on location, creating issues such as home and infrastructure damage, increased susceptibility to flooding and loss of groundwater storage capacity. Climate change could increase these pressures in certain areas through more frequent droughts and heatwaves and changing groundwater recharge patterns.

Satellite radar has changed the way researchers study land movement. Europe’s Copernicus Land Monitoring Service, particularly the European Ground Motion Service, provides open-access information on ground motion across most of the European landmass. It helps researchers identify areas of subsidence and compare developments across countries. However, to understand why some land is sinking, satellite measurements need to be combined with subsurface knowledge: geology, groundwater levels, soil properties and human activities both above and below ground.

An international group of researchers, led by the Geological Survey of the Netherlands and including experts from BGS, has authored a new paper, Lessons learned from European land subsidence, exploring the insights Europe has gathered from decades of studying land subsidence. The paper highlights the fact that such subsidence is not only a scientific concern but also a societal one, which needs a multi-system approach to ensure it is properly managed.

What causes subsidence?

The study describes a wide range of natural and human-induced processes that can contribute to land subsidence, including:

• tectonic movements
• groundwater extraction
• mining
• hydrocarbon extraction
• soft soils
• natural ground compaction

The researchers also point to possible new causes linked to the energy transition. Technologies such as geothermal energy, carbon capture and storage, underground gas storage and hydrogen storage all make use of the subsurface. Depending on local conditions and how these systems are operated, such activities may influence ground motion. This makes careful monitoring and integrated assessment essential.

Land subsidence is common across Europe. In the UK, we have measured subsidence up to 2 cm per year in some costal areas. This has important implications for coastal erosion and long-term impacts from sea level change.

Ekbal Hussain, remote sensing geoscientist.

Better decisions need better data

Better subsurface insight helps governments, industry and society make more informed decisions about water, infrastructure, climate adaptation and the energy transition.

Europe already has an important foundation for this: open data infrastructures, national monitoring programmes and cooperation between geological surveys, research institutes and policymakers. The challenge now is to bring this data together more effectively. By combining satellite observations with subsurface data and physics-based models, governments and industry can better distinguish between possible causes of land subsidence, assess future risks and weigh appropriate measures. It is hoped that this knowledge will support future risk assessment and decision-making across Europe.