20 years of continuous SAR observations benefit landslide studies
The SBAS-DInSAR technique has been applied to ERS, ENVISAT and Cosmo-Skymed data to analyse and model the Ivancich landslide, Assisi, Central Italy. Use of ERS and ENVISAT data has allowed to estimate the long-term dynamic behaviour of this deep-seated, translational slide over a period of 18.6 years, and to compare and validate SAR deformations retrieved over the Line Of Sight with contemporaneous inclinometer time-series acquired in the interval 1998-2004/5.
In addition, availability of satellite observations over such long data interval allowed the authors to investigate the correlation between rainfall and measured displacements: a quasi-linear temporal behaviour of the landslide deformation was found, independent from precipitation. This information has been then used, with in-situ data and a much larger density of scatterpoints derived from the CosmoSkyMed X-band data acquired between 2009-2012, to create a two-dimensional model of the kinematic evolution of the landslide using a Finite Element Method approach. The retrieved model shows a good agreement with the available inclinometric data.
The research was conducted in the framework of the FP7 DORIS project, and it is continuing in the FP7 LAMPRE project . The study has been published in the paper "Enhanced landslide investigations through advanced DInSAR techniques: The Ivancich case study, Assisi, Italy" authored by Fabiana Calò, Francesca Ardizzone, Raffaele Castaldo, Piernicola Lollino, Pietro Tizzani, Fausto Guzzetti, Riccardo Lanari, Maceo-Giovanni Angeli, Fabrizio Pontoni, Michele Manunta, on Remote Sensing of Environment 142 (2014) 69-82.
The attachment below provides an animation of the modelled total displacements over time resulting from the combination of the deformations observed from space with in-situ data.