InSARInSub – ESA-supported project on the use of satellite data about terrain change

New project makes satellite data about ground motion user-friendly

An understanding of landscape dynamics and how they are affected by human activity is a prerequisite of a robust decision-making basis, such as when planning climate adaptation measures, construction and infrastructure investments and investments in pipeline networks.

Overall post-glacial land uplift is well documented and well described. Local land uplift and subsidience is, however, mostly undocumented and often unknown.

The Vognsen Model

Available satellite data about vertical ground motion is highly complex

In 2018 and 2019, SDFE (the Danish Agency for Data Supply and Efficiency) made freely available a nationwide calculation of vertical ground motion for use in scenarios such as climate adaptation. The SDFE calculations contain valuable information about the dynamics of ground motion at a local level. This data is so complex, however, that a correct interpretation requires an understanding of the core principles of radar interferometry. As a result, the practical application of this data by companies and authorities is no straightforward matter.

The project will link satellite data about ground motion with geotechnical data

This is being addressed in Geopartner’s project, which focuses on making this data more user-friendly. On the one hand, methods must be developed to calibrate and refine the satellite-calculated vertical motion by linking them with local in-situ measurements. On the other, interconnecting this data with detailed information about subsoil will be presented in the form of a 3D geological model. Specifically, the project will develop methods to calculate more robust ground motion products by incorporating knowledge about local factors and historical elevation measurements from levelling surveys.

The project is supported by the European Space Agency, ESA

The project is supported by the European Space Agency, ESA and executed by Geopartner Landinspektører A/S, Geo, DTU Space with Klimatorium as strategic partner.

Sentinel-1_radar, which is part of the ESA satellite programme to collect data about vertical ground motion
Sentinel-1_radar satellite, which is part of the ESA satellite programme to collect data about vertical ground motion. Photo:ESA

New tools in development in partnership with end users

A select group of end users is helping to define and develop these tailor-made data services. The tools will provide important input that will support climate adaptation decisions when dimensioning and designing new building projects and underground infrastructure, and will also serve as an aid in risk management and decisions when determining the future locations of facilities both above and below ground.

Large local variations in ground motion

There can be significant local/regional differences in vertical motion nationwide. This is related to the geological composition of the subsoil. Denmark’s largest motions are found in low-lying areas near watercourses and fjords, as well as in urban areas, especially in older urban districts and at landfills and port facilities.

Motion in some places can be measured as centimetres per year. It can thus be of significantly greater importance in, for example, the long-term planning of coastal climate adaptation measures than the issue of rising sea levels caused by climate change, which totals 4-5 millimetres a year as far as Denmark is concerned.

Knowledge about local ground motion is a prerequisite for decisions that are based on data

Real-time knowledge about local landscape ground motion can therefore make a significant contribution to municipalities’ work in the field of climate adaptation and can in many cases be a prerequisite for being able to provide an accurate data-based estimate of safety levels for dykes, infrastructure and buildings.

Knowledge about vertical ground motion and the geological composition of the subsoil is also crucial when establishing or renovating rainwater and sewage pipes. These typically have a service life of 70-80 years. Detailed local knowledge about ground motion allows a new approach to maintenance, as it will be possible to prevent incidents and plan pipeline renovation work. This will mean major savings in operating and construction costs, while increasing security of supply.

For larger building and construction projects, knowledge about ground motion and subsoil is crucial to finding the right location for a project and the right basis for investment.

In other words, refined vertical motion data has a broad potential for application and will be able to streamline many tasks and work processes, saving society millions of DKK.

Satellite-based technology can replace analogue surveying techniques

This new space-based technology will largely be able to replace expensive “analogue” surveying techniques. It will be able to provide updated calculations on an ongoing basis, incorporating the latest data at hereto unprecedented levels of spatial detail.

The project will run for a two-year period until early 2022. The initial focused solutions are already expected to be ready as a beta version at the end of 2020.

Geopartner is part of other major sponsored projects. See what they are here

Contact for further information about the project:

Niels Henrik Broge
Chefkonsulent
Mobil +45 4131 8534
nhb@geopartner.dk