Land subsidence is becoming increasingly visible in parts of Europe. In a paper published in the scientific journal Nature Sustainability, a team of European researchers, including Francesca Cigna of CNR-ISAC, explains why better monitoring, shared data and a deeper understanding of the subsurface can help assess and manage its impacts.

Land subsidence — the gradual sinking of the Earth’s surface — affects many areas across Europe, but its causes and impacts vary greatly from place to place. In coastal areas, it can contribute to relative sea-level rise and greater flood exposure. Depending on local conditions and the processes involved, it may also damage buildings and infrastructure or gradually reduce aquifer storage capacity. In this research, an international group of researchers examines what Europe has learned from decades of studying land subsidence and how this knowledge can support future risk assessment and decision-making.

What causes the ground to sink?

The study describes a wide range of natural and human-induced processes that can contribute to land subsidence. These include groundwater extraction, mining, hydrocarbon production, peatland drainage, loading on soft soils, tectonic movement and long-term geological adjustment after the last ice age. Human-induced causes are particularly relevant for policy and management, because in some cases their effects can be reduced through changes in land use, regulation or monitoring.

Satellites show the movement — not the cause

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 sinking areas and compare developments across countries. But it does not explain everything. To understand why land is sinking, satellite measurements need to be combined with subsurface knowledge: geology, groundwater levels, soil properties and human activities below ground.

When sinking land affects everyday life

The consequences are already visible in several regions. In a number of European coastal floodplains, land is subsiding while sea levels continue to rise. Damage to buildings, roads and critical infrastructure can be substantial in affected areas, and the loss of groundwater storage capacity may pose an additional risk to water security. Climate change could increase these pressures in certain areas through more frequent droughts, heatwaves and changing groundwater recharge patterns.

The energy transition moves underground

The researchers also point to possible new challenges 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 cause or influence ground motion. This makes careful monitoring and integrated assessment essential.

Better decisions need better data

Europe already has an important foundation: open data infrastructures, national monitoring programmes and cooperation between geological surveys, research institutes and policymakers. The challenge now is to bring these 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.

Where policy and management can make a difference

The paper shows that land subsidence is not only a scientific issue. Many of its drivers are linked to human choices, from groundwater use to energy production and land management. This also means there are opportunities to reduce risks. Better subsurface insight helps governments, industry and society make more informed decisions about water, infrastructure, climate adaptation and the energy transition.