Researchers within the EC-funded SUBMERSE project have demonstrated how existing submarine cables can be transformed into powerful Earth observation tools using Distributed Acoustic Sensing (DAS) technology.
In a recent blog post for the EGU Seismology ECS division, SUBMERSE researcher David Schlaphorst shares how DAS on a single submarine cable off the coast of the Portuguese island of Madeira in the Atlantic Ocean was used to detect a variety of signals, including earthquakes, ocean waves and tides, and even whales. This work showcases how DAS enables monitoring of features and parameters that were previously hard or even impossible to observe using existing technologies like single seismic stations.
Watch the video below to hear directly from David about his findings, what surprised him most, and why DAS could transform how we monitor the oceans.
The findings featured in the blog post build on a recent publication by SUBMERSE researcher Afonso Loureiro and co-authors (Loureiro et al., 2025; preprint; under review), further illustrating the value of fibre sensing for ocean and Earth monitoring.
This research highlights the potential of DAS for improving our understanding of ocean and Earth systems, supporting more effective monitoring and early warning tsunami and seismic capabilities.
The SUBMERSE project, funded by the European Commission, aims to advance the use of submarine cables for seismology, marine biology, and oceanography, building on collaborations across European research institutes and infrastructure providers to turn existing cables into scientific tools for the benefit of society.
Read the original article on the EGU blog here.
Image captions
Figure 1: Map of the Madeira archipelago, showing locations of the cable and permanent seismic stations. Red line: approximate location of the GeoLab fibre. Blue triangles: permanent broadband seismic stations. White triangles: permanent short-period seismic stations. Yellow star: local earthquake recorded during the data acquisition period. Topography and bathymetry source: GEBCO Compilation Group (2023).
Figure 2: Tidal imprint on the strain rate observed at the section of the cable entering the sea. a) root mean squared (RMS) calculated on 5 min windows between 2.25 km to 2.45 km cable distance for the first 24 h of recording. b) Tide heights calculated for Funchal. Note that the tidal amplitude is less than 3 m, but the signal of the waves hitting the beach is discernible along a ∼70 m slant distance.