Ground motion monitoring of Italian regions to prevent and mitigate natural disasters and support urban development

Since 2014, and the launch of the first ESA Copernicus’ Sentinel-1A radar, and later, Sentinel-1B, TRE Altamira has joined forces with the Civil Protection Centre of the University of Florence, in order to detect and monitor ground motion and land subsidence of areas in Italy, such as the regions of Toscana, Veneto and Valle d’Aosta.

The region of Toscana has been the focus of a great deal of attention, especially the central portion of the territory which includes the cities of Pistoia and Montemurlo – well-known areas for subsidence.

Deformation map of Montemurlo area. The area in red is where motion acceleration has been detected, recognizable from the time-series below.

Land subsidence is usually due to a combination of elements such as groundwater overexploitation, mining, natural consolidation of sediments, and rapid urbanization.

Recent innovations in InSAR data collection have contributed to new standards in satellite-based monitoring systems. Stacks of Sentinel-1 images are promptly processed with our SqueeSAR® algorithm after each new acquisition, allowing for systemic detection of ground deformation and continuous monitoring.

Region of Toscana (Italy): a monitoring service is active over the whole region. On the left image, pink dots indicate areas of higher variation as detected by an automated trend detection tool and are superimposed on the regular displacement velocity map. Trend detection identifies areas where a significant change in the motion has occurred.

This technology complements conventional techniques which are often impractical and cost-prohibitive for long-term and wide-scale monitoring and allows for the creation of ground deformation maps as part of a regional monitoring system.

InSAR data provides a reliable way of detecting ground deformation phenomena such as ground subsidence, landslides, and the effects of the exploitation of geothermal resources across wide areas. The data can help identify ground instabilities that may represent a major threat and permit timely mitigation strategies for geohazard risk reduction.

Ground motion monitoring is also necessary to support urban development projects and risk assessment efforts in order to prevent damage to the economy and the environment.

The work behind the monitoring project of the region of Toscana and their applications is on-going. The same procedure can be transferred to other areas of Italy and could be a key factor in fostering the improvement of natural disaster prevention.