On-Demand Sentinel-1 InSAR processing service
29 April 2016
The Sentinel-1 mission flying under Europe's Copernicus Programme offers a powerful system for monitoring surface displacement through the Interferometric SAR (InSAR) technique. It acquires Synthetic Aperture Radar (SAR) data on a global scale, and operates under an open and free data access policy.
The satellite uses an Interferometric Wide Swath (IWS) mode to obtain the raw digital radar data about the Earth's surface. Accurate and specific processing algorithms are required in order to turn this raw data into visual information products, and this layer of expertise can discourage users who are not familiar with InSAR techniques from using the data.
To promote wider use of Sentinel-1's SAR data, increase research on interferometric techniques and make it easier for people to produce accurate Sentinel-1 InSAR measurements, CNR-IREA has developed a web tool which, through a user-friendly interface, enables users to generate interferograms in an automated and unsupervised way (see Figure 1). With this service, users can select SAR images from the Sentinel data repository, set a few processing parameters, and then automatically process imagery and retrieve the interferogram which shows the changes in the surface area detected by the radar.
This map (interferogram) captured the Earth's surface displacement induced by the Mw 8.3 Illapel (Chile) earthquake of 19 September 2015. The interferogram has been generated by exploiting two Sentinel-1 images acquired before and after the event, respectively. Each colour cycle corresponds to a displacement of about 2.8 cm.
CNR-IREA developed its InSAR web tool in the context of the Geohazards Thematic Exploitation Platform (Geohazards TEP). Designed for exploitation on the Geohazards TEP, the web tool has been available to users from the geohazards community since April, as an initial prototype in ESA's Grid Processing On Demand (G-POD) infrastructure. The prototype will evolve into a pre-operational service on the Geohazards TEP by early 2017.