As from October 6, 2022, the MPIC-OPT services are becoming the GDM-OPT services ! GDM-OPT stands for Ground Motion Monitoring with OPtical image time series and it has been chosen as a new name for the services derived from the processing chain MPIC. GDM-OPT is developed, exploited and maintained by CNRS/EOST for the Data-Terra / ForM@Ter Earth Solid DataHub with the support of ESA and of CNES.

The GDM-OPT services are constantly evolving to suit the needs of the geohazards community in terms of ground motion monitoring from image correlation and optical flow techniques. There are three different GDM-OPT services addressing respectively the measurement of co-seismic displacement (GDM-OPT-ETQ), the monitoring of ice motion (GDM-OPT-ICE) and of landslide motion (GDM-OPT-SLIDE). The same processing chain is used for all the services but default parameters and tailored options are made available to the GEP users.
For more information and examples, have a look at the different tutorials: GDM-OPT-ETQ, GDM-OPT-ICE, GDM-OPT-SLIDE.

In order to improve user uptake, a Frequently Asked Questions (FAQ) section is also now published on the GEP documentation. Beside the tutorial explaining in details the parameters available in the different GDM-OPT service, the FAQ aims at answering simple questions and/or problems that the user may encounter. The questions currently addressed:

  • the core principle of GDM-OPT services,
  • basic errors user usually do when they start using GDM-OPT,
  • examples of the influence of the different parameters and tips on how to set them.

The FAQ will be updated with in coming questions and problems that users may encounter repeatedly.

A recent example of GDM-OPT-ETQ products is the Mw 6.9 Taiwan earthquake of September 18, 2022. The co-seismic offset could be measured with the GDM-OPT-ETQ services using the pre- and post-earthquake Sentinel-2 acquisitions. A displacement of around 1-2 m is measured in the North-South direction along the fault.

Figure : GDM-OPT-ETQ results over Taiwan. Contained modified Copernicus Sentinel-2 images (2022). Public results available here.