National Initiatives

Research projects such as GMES Terrafirma demonstrated the maturity of advanced DInSAR techniques, like e.g. PSI, SBAS, with respect to operational processing and usability of the derived information content. The technological progress and the existence of multiple spaceborne SAR missions, ensuring long-term data availability, result in an increasing interest within the geohazard community to use this technology. However, no operational ground motion service exists in Germany and thus the valuable information content is not fully exploited by national end-users, e.g. geologic agencies. Therefore, BGR initiated the realization of a national ground motion service in 2016.

The service is based on two data-product categories, these are i) successively updated wide-area PSI datasets, based on Sentinel-1 IW data, covering the entire nation and ii) high spatial resolution surface motion datasets, based on e.g. TerraSAR-X stripmap data, which are provided after user request.

This presentation focuses on the definition and realization of an operational value-added product regarding (semi-) automatic landslide inventory update. A current pilot study demonstrates the workflow. It is based on ascending and descending Sentinel-1 IW PSI datasets, ancillary data (a priori landslide inventory, lithological map, DEM) and ground-truth campaigns. The area of interest is located in the Berchtesgadener Land in South-East Germany and is characterized by various mass movement processes, ranging from e.g. soil creep, shallow landslides, deep seated rotational landslides to rock falls. Based on the PSI data a motion decomposition (East-West, up-down) is performed to derive a 2D velocity vector. The PS displacement time series is automatically classified into predefined motion trends, such as linear, quadratic, and discontinuous to assess the motion characteristics in more detail. These data products as well as the ancillary data are used in a Bayesian framework to update the landslide inventory. The validation results, based on a comparison with ground-truth data, are reported and the transferability of the workflow is discussed to complete the presentation.

A national InSAR-based deformation mapping service in Norway was launched in May 2016. The mandate of this service is to provide the public in Norway with nationwide deformation products. The products are to be generated primarily, but not exclusively, using Sentinel-1 data.

The service will provide periodically updated deformation data, with varying resolution for urban and non-urban areas. The products will be made available to various local, regional and national authorities via appropriate web GIS protocols. The data will also be made available to the public via a web map interface with simple tools to query and visualize the information.

In general, the realization of such a service introduces a number of challenges that can be summarized with the word “scaling” -- scaling of processing system, algorithms, products, data management, dissemination, etc. Many of these issues are, in the case of Norway, further amplified due to long winter season, rough topography, fjords, as well as the spatial extent of the country.

In this contribution, we will present our approach by outlining the basic product and algorithmic requirements that serve as a driver, as well as describing ongoing research and development activities needed to meet the identified requirements.

We will conclude by presenting and discussing two examples of large-scale deformation maps. One with regional coverage based on RADARSAT-2 data from 2009-2016, and the other, with national coverage, based on Sentinel-1 data from 2014-2017.

EPOS, the European Plate Observing System, is a pan-European ESFRI initiative to connect distributed Research Infrastructures (RI) with the aim to facilitate the integrated use of data, data products, software and services in the domain of solid Earth science. EPOS integrates a large number of existing European RIs belonging to several fields of the Earth science, from seismology to geodesy, near fault and volcanic observatories as well as anthropogenic hazards. The EPOS vision is that the integration of the existing national and trans-national research infrastructures will increase access and use of the multidisciplinary data, including Earth Observation (EO) satellite images and other sources of data recorded by the solid Earth monitoring networks, acquired in laboratory experiments or produced by computational simulations. The establishment of EPOS will foster the interoperability of products and services in the Earth science field to an international community of users.

Accordingly, EPOS aims at representing a scientific vision and approach in which innovative multidisciplinary research is made possible for a better understanding of the physical processes controlling earthquakes, volcanic eruptions, unrest episodes and tsunamis as well as those driving tectonics and Earth surface dynamics. To do this, EPOS is adopting appropriate legal solutions to manage distributed pan European Research Infrastructures, in order to guarantee a common and shared data policy, the open-access and transparent use of data, and the mutual respect of the Intellectual Property Rights.

Among the several fields in the framework of Earth sciences, one of the EPOS components deals with advanced satellite products and services. In particular, the Thematic Core Service (TCS) referred to as Satellite Data aims at developing, implementing and deploying advanced satellite products and services, in particular using the Sentinel-1 and Sentinel-2 missions of the Copernicus programme of the European Union. Moreover, this TCS will deliver an effective satellite data procurement coordination with the Space Agencies and the involvement of the scientific community of satellite data users in a common collaborative framework to guarantee a long-term operational supply of state-of-art satellite products and services suitable to significantly contribute to the scientific advancement in the understanding of our Planet.

This work intends to present the technological enhancements, fostered by EPOS, to deploy effective satellite services in a harmonized and integrated way. In particular, the Satellite Data TCS will deploy five advanced services, EPOSAR, GDM, COMET, 3D-Def and MOD, designed to provide information about relevant geohazard features such as faults and terrain motion phenomena (Figure 1). In particular, the planned services will provide both advanced DInSAR products (deformation maps, velocity maps, deformation time series) and value-added measurements (source model, 3D displacement maps, seismic hazard maps). Moreover, the services will release both on-demand and systematic products: the latter will be generated and made available to the users on a continuous basis, by processing each Sentinel-1 data once acquired, over a defined number of areas of interest; while the on-demand services will allow users to select data, areas, and time period to carry out their own analyses.

The satellite components will be integrated within the EPOS infrastructure through a common and harmonized interface that will allow users to search, process and share remote sensing images and results. This gateway to the satellite services will be represented by the ESA- Geohazards Exploitation Platform (GEP), a new cloud-based processing environment to support the use of Earth observation with both SAR and Optical services relevant to geohazard risk assessment (Figure 2). The Satellite Data TCS will use GEP as the common interface toward the main EPOS portal to provide EPOS users not only with products but also with relevant processing and visualisation software. In particular, TCS Satellite Data is going to adopt an approach as wide as possible to integrate national RIs, that allows the TCS service providers to federate national computing facilities, to access to external computing resources (cloud computing) and to make available state-of-art satellite products for the scientific community.

In this work, we describe and demonstrate several services utilizing capabilities of Forestry Thematic Platform (F-TEP) for processing of satellite interferometric SAR (InSAR) data for creating value added forest variable maps.

The objective of F-TEP is to change the concept of Earth Observation (EO) in forestry, with a vision of a one-stop shop for forestry remote sensing services for both academic and commercial sectors. Three basic usage scenarios are supported: exploitation, service development and product development. F-TEP is organized as combination of a web portal and a full virtual environment that offers access to a range of free EO processing software and Copernicus satellite data. Proprietary software and third party satellite and reference data and value added products can be available via F-TEP as well

Specific InSAR data based services enable production of forest variable maps using state-of-the-art approaches utilizing satellite data available from ESA Sentinel-1 sensors, as well as TanDEM-X and ALOS PALSAR data. The products include forest cover maps, forest stem volume (above ground biomass) and forest tree height maps. Several scenarios demonstrating capabilities of implemented image processing chains will be evaluated using the same set of stand and plot level reference data available from several study sites in Mexico (states of Chiapas and Durango) and Finland.

A separate service utilizing interferometric SAR data from TanDEM-X and ESA Sentinel-1 satellites is implemented in the framework of one of ESA DUE Innovator projects, AccuCarbon. The project develops and demonstrates a pioneering service on estimating the carbon storage of tropical forest (over Mexican study sites), where information on initial state of forests is combined with information on forest change to model carbon stocks at any point and time of interest. InSAR data is used to provide forest change information in the service, and can be flexibly used along with other multi-sensor SAR and optical satellite data.

Functionalities of the Platform and implemented services will be demonstrated at the conference. 

The Netherlands is known to be mostly located beneath sea level. Subsiding land in combination with rising water levels, both from sea and increased river discharge, increase the load on its water defense systems. Although failure of these systems is still at low risk, the impact of a failure would be huge. Not only the risk of flooding, but also the ground motion itself has large impact on the environment. Land subsidence is mainly man-induced, such as peat compaction caused by water table management, gas extraction, and salt mining. Infrastructure built on these moving surfaces suffers strong consolidation if newly built, or in case of existing infrastructure foundation degradation and potential internal stresses leading to failure.

A multitude of pilot studies on local sites have demonstrated the great potential of InSAR in the Netherlands. Currently we are in the initial phase of lifting the technique to a nationwide scale. The motivation is to be able to integrate the InSAR deformation data into Rijkswaterstaat monitoring strategies, and making them more efficient and cost-effective.

The service will be based on Sentinel-1 data, potentially supplemented with RADARSAT-2 data, which is made available for the territory of the Netherlands by the Netherlands Space Office (NSO). The monitoring service will provide annual nationwide updates with more frequent updates for hot-spot locations. While initial products will be based on a Persistent Scatterer Interferometry (PSI) technique, the long term objective is to optimally integrate PSI and small baseline techniques in order to utilize the InSAR information to its full potential. Finally, for quality control purposes, a number of active transponders and passive corner reflectors are being deployed.

In this contribution we will demonstrate initial results and their possible applications within some Rijkswaterstaat’s core activities: guided updating of the Dutch height reference system (NAP), guiding in-situ monitoring of infrastructure, and monitoring tools for unexpected deformation at water defense systems and railways.