The Copernicus European Ground Motion Service (EGMS) validation: a landslide monitoring prospective.

The advent of the EGMS service offers chances and opportunities to EU Member States practitioners and researchers into the field of landslide monitoring. As member of the EGMS validation team, under the lead of SIXENSE, the Geosphere Austria carried out the in situ validation activity for five test sites spread over Europe. The focus of this paper is the inter-comparison of an automatic geodetic monitoring system installed at two landslide locations in Tyrol, Austria against the main products offered by the EGMS:

• level 2a
• level 2b
• level 3

The comparison was performed in a Jupiter hub environment created ad hoc for the validation project by our partner Terrasigna. The workflow was developed in R language and validates error, precision and accuracy of the (in-situ) velocities and time series (TS) against the correspondent MT-InSAR values of the EGMS.

The workflow is made of several highly customisable modules:

• reads and visualises the two datasets;
• performs a series of analysis such as smoothing (simplification), outliers search and trends for both time series;
• inter-compares all the combinations of derived TS datasets and calculates for each couple RMSE, Coefficient of Determination (R²) and index of agreement;
• plots the TS and bar diagrams of the best scores in terms of minimum errors, maximum accuracy and maximum precision;
• delivers a Quality Index (QI) between 0-1 for each EGMS product;

The results of the in-situ validation activity will be presented and explained. In fact, considering the type of natural hazard (deep-seated gravitational slope deformation) and his location (vegetated and high relief alpine morphology), this validation set the perfect example to discuss strength and weakness of the EGMS if compared to state-of-the art in-situ monitoring systems installed in such extreme and remote areas.