National geohazards mapping in Europe: Interferometric analysis of the Netherlands

Abstract

The launch of Copernicus, the largest Earth Observation program to date, is significant due to the regular, reliable and freely accessible data to support space-based geodetic monitoring of physical phenomena that can result in natural hazards. In this study, wide area interferometric synthetic aperture radar (InSAR) capability is demonstrated by processing 435 Copernicus Sentinel-1 C-Band SAR images (May 2015 -May 2017) using the Intermittent Small Baseline Subset (ISBAS) method to produce a wide-area-map (WAM) covering 53,000 km 2 of the Netherlands, Belgium and Germany. The ISBAS-WAM contains over 19 million measurements, achieving a ground coverage of 94%. The retrieval of measurements over soft surfaces (i.e. agricultural fields, forests and wetlands) was crucial due the dominance of non-urban land cover. A statistical analysis of the velocities reveals that intermittently coherent measurements in rural areas can provide reliable, additional deformation information with a very high degree of confidence (5σ), which spatially correlates to known deformation features associated with compressible soils, infrastructure settlement, peat oxidation, gas production, salt mining and underground and opencast mining. The spatial distribution of deformations concurs with independent data sources, such as previous persistent scatterer interferometry (PSI) deformation maps, models of subsidence and settlement susceptibility, and quantitatively with GPS measurements over the Groningen gas field.Remotely derived deformation products, with near complete spatial coverage, provide a powerful screening tool for mitigation and remediation of geological and geotechnical issues to help in the protection of assets, property and life. The ISBAS-WAM demonstrates that routine generation of such products on a continental scale is now theoretically achievable, given the establishment of the Copernicus programme and the development of state-of-the-art InSAR methods, such as ISBAS.

Review of Works Combining GNSS and InSAR in Europe

“…The Subsidence/Uplift class (4.4%) includes surface deformation analyses performed at a large, regional or national scale, in which both subsidence and uplift phenomena can be identified. Case studies were identified in Netherlands, such as surface deformation analyses performed over the whole national territory [176][177][178][179] or monitoring works of the water defence structure of Waddenzee and IJsselmeer [180,181]. Two other scientific contributions focused on the Polish and Lithuanian Baltic coastal areas [105] and the surface displacement pattern affecting the permafrost areas in northern Norway [75].…”

Comment on nhess-2021-35

“…The new generation of SAR sensors (e.g. Sentinel-1, ALOS2 PALSAR2, TerraSAR-X, COSMO-Skymed and Radarsat-2) are now regularly operate in orbit with very short revisit time which enable InSAR achieve wide-area monitoring of ground displacement at high precision (Gee et al 2019).…”

Large-Scale Subsidence Geohazard Monitoring With Sentinel-1 Sar Interferometry in Central Lishui (China)

“…Moreover, the new generation of SAR sensors including Sentinel-1, ALOS2 PALSAR2, TerraSAR-X, COSMO-Skymed which operate in orbit with short revisit cycles enable the widearea monitoring of ground displacement at high precisions nowadays (Gee et al, 2019).…”