InSAR monitoring for the natural environment
Natural ground movements - from slow landslide creep to tectonic fault displacement - affect communities, infrastructure, and land management decisions. InSAR provides systematic monitoring across landscapes, revealing patterns of movement that inform hazard assessment and mitigation planning.
Coastal erosion and cliff stability
Coastal cliff recession threatens clifftop properties, infrastructure, and communities.
Understanding erosion rates and identifying sections of coast undergoing accelerated retreat supports planning decisions, property risk assessment, and coastal management strategies.
InSAR monitors cliff top displacement and the subtle ground movements that often precede visible erosion events. Detecting zones of instability before failure occurs provides valuable lead time for risk management.
InSAR is particularly suited to coastlines where access for ground surveys is difficult or dangerous, and where the scale of monitoring required exceeds practical survey capacity.
Our work at Ventnor on the Isle of Wight demonstrated InSAR monitoring of complex coastal ground movements in an urbanised setting.
The study tracked displacement patterns across the coastal zone, correlating ground behaviour with rainfall and identifying areas of ongoing movement affecting clifftop properties - the kind of intelligence that supports both individual property decisions and strategic coastal management.
Landslide hazards
Landslides range from sudden catastrophic failures to slow, persistent movements that damage property over years.
InSAR detects both, identifying areas of active ground movement and tracking changes in displacement rate that may indicate evolving hazard.
This supports landslide inventories, hazard zonation, and monitoring of known problem areas.
Peatland monitoring
Peatlands undergo complex seasonal and long-term movements related to water content and vegetation condition.
InSAR detects these subtle changes across extensive peat landscapes, supporting condition assessment, restoration monitoring, and carbon stock management.
Geological and tectonic monitoring
Active faults and seismic zones require long-term monitoring to understand ground behaviour and assess hazard. Faults considered dormant may exhibit subtle ongoing movement that conventional surveys miss.
InSAR's ability to detect sub-millimetre displacements over wide areas makes it uniquely suited to characterising fault activity and identifying previously unrecognised structures.
InSAR supports broader geological characterisation - mapping subtle surface expressions of underlying structure, identifying differential movement across geological boundaries, and detecting ground responses to deep processes.
For major infrastructure projects requiring detailed geological risk assessment, InSAR analysis adds a dynamic dimension to traditional geological mapping, revealing how the ground actually behaves rather than inferring behaviour from static observations alone.
Our research at the Gobi Desert, China, used InSAR to monitor micro-displacements on active faults at a candidate site for radioactive waste disposal.
The study detected millimetre-scale movements on faults previously considered inactive and identified eleven previously unknown fault structures through displacement analysis.
Groundwater effects
Groundwater abstraction causes regional subsidence in many areas, with effects that may take years to fully manifest.
InSAR maps these broad subsidence patterns, tracking their extent and identifying areas where extraction is causing problematic settlement.
This supports sustainable groundwater management and early identification of emerging problems.
River bank stability
River bank erosion and instability affect both natural systems and adjacent land uses.
InSAR identifies sections of bank showing movement, supporting prioritisation of stabilisation works and monitoring of intervention effectiveness.
Sinkhole-prone areas
Regions underlain by soluble geology - limestone karst, gypsum, salt - may develop sinkholes with little surface warning.
InSAR detects the precursor subsidence that often precedes collapse, providing early warning that enables investigation and intervention before sudden failure.