The national research data networks can – using so-called DAS or SoP technology – serve as sensors for monitoring earthquake zones, volcanoes or oceans.

The new EU-funded project, SUBMERSE (SUBMarine cablEs for ReSearch and Exploration) has started. It aims to utilise existing submarine telecommunication cables already in use for networking the research and education community as sensors to monitor the Earth systems, e.g. volcanoes and earthquakes or the ocean. In particular, existing submarine cables of the respective national research and education data networks (NREN) will be used for this purpose. As they can be used in a new way, the project not only avoids the need for extra hardware under the sea, but also improves the return on existing investments.

24 partner institutions

Coordinated by the European Future Innovation System (EFIS) Centre, 18 direct partner institutions are working together, including the GFZ German Research Centre for Geosciences; five institutions are affiliated and one is associated. During the 36-month project, they will cooperate closely with the diverse research communities who intend on using the data. The project started on 1 May 2023. It is funded by HORIZON Europe's €10 million programme "R&D for the next generation of scientific instrumentation, tools and methods".

Shared data service and research results

The aim is to jointly design and build a data service and thereby creating a highly collaborative environment where data is generated by and for all parties. In this way, SUBMERSE goes beyond the traditional model of supporting and facilitating global research and education with infrastructure, to an environment where project partners and research communities together generate and share research from that infrastructure for multiple purposes.

Basis: Proven use of fibre optic cables as sensors

The basis for this project is the pioneering work of National Research- and Education Networks and their partners from universities, research institutes and industry in parts of Europe over the last five years, demonstrating the principal usability of submarine fibre optic cables to monitor different subsystems of the Earth for use cases in the geosciences, oceanography and marine biology. The methods and technologies used have varied. However, two techniques have shown particular promise in terms of the detail and scalability of their deployment: Distributed Acoustic Sensing (DAS) and State of Polarisation (SoP).

In DAS, the optical fibres are used as strain sensors: They are deformed by movements of the subsurface and the transmitted signals are distorted. From the analysis, information about the movement of the Earth can be derived and both earthquake waves and processes in the water column above the ground can be recorded. Similarly, with SoP, the change in polarisation, i.e. a certain property of the light transmitted through the cables, can be used to learn something about the deformation of the cable. DAS offers high spatial resolution of a few metres, but a limited range of about 100 kilometres, while SoP can also be used transoceanically, but the location of the deformation can only be determined very roughly.

The principle usability of both approaches for use cases in the geosciences, oceanography and marine biology has been demonstrated in pilot studies. The geographic locations where experiments have taken place, the length of experiments, the types of technologies used, and technological readiness levels of those technologies used vary substantially from country to country.

Next step: Making data available to science, civil society and industry

The level of technological development and cooperation between infrastructures associated with this field is now mature enough to aim for the next paradigm change: making data available from continuous observations on multiple existing submarine optical fibre telecommunication cables, using a standardised technological configuration, at a continental scale, available to the wider scientific community, civil society, and industry.

The SUBMERSE project seeks to create and deliver a pilot activity which would serve as a blueprint for continuous monitoring upon many more cables in the future, which would lead to the opening of new market opportunities and the demonstration of methods to maximise the output of investments in research infrastructures, by using the by-products of their operations for the purposes of new scientific research. This would lead to the integration of established regional and national research infrastructures made accessible though unified data portals, thereby enabling world-class European research not possible before.

SUBMERSE Project Coordinator, Carmela Asero of EFIS, adds:

“All partners are excited to begin work on this highly innovative project. We have an opportunity here to do something really quite amazing, making use of existing infrastructure to provide a world of new data and, together with the research communities making use of this data, potentially make new discoveries!”

Project work at the GFZ

Frederik Tilmann, head of Section 2.4 Seismology, is the head of the project's GFZ activities. The GFZ leads work package 3 on use cases and coordinates the task on the geoscientific use of the cables. In particular, methods for localising earthquakes using the acquired data will be developed and implemented at the GFZ. In addition, contributions are being made to calibrate the data using conventional ocean floor sensor technology.

Further information on the project partners and the planned working packages can be found soon on the project website:

https://submerse.eu/