How Europe Is Turning Internet Cables into Ocean Ears

SUBMERSE turns data cables into ocean sensors, merging connectivity with climate and security insight.

10 Oct 2025

Europe is reimagining its digital lifelines beneath the sea. The EU-backed SUBMERSE project is turning select research and education network cables into smart ocean sensors, offering a fresh way to watch over the continent’s vast underwater infrastructure.

For years, the cables stretching across the Atlantic and North Sea have quietly carried the world’s data. Now, with advanced light-based sensing, they can also listen to the ocean, detecting earthquakes, tracking marine activity, and spotting threats to connectivity in real time. Pilot tests by NORDUnet, a key project partner, have shown that these dual uses do not interfere with normal data flow.

The timing is no coincidence. As Europe’s digital dependence grows amid geopolitical tension, smarter subsea systems could provide crucial early warnings of cable damage or seismic shifts. “We’re essentially giving the ocean a voice,” said one project researcher. “These cables already span the planet; we’re just teaching them to speak.”

The potential benefits reach far beyond telecoms. Governments could sharpen disaster-response systems. Energy firms might track offshore platforms more safely. Marine scientists could gain a clearer picture of how climate and human activity shape the seas. SUBMERSE also supports the European Commission’s Cable Security Toolbox, part of a broader effort to guard Europe’s digital backbone.

Still, challenges remain. Coordinating standards, balancing international cooperation, and managing data access will all test the project’s ambitions. Yet optimism runs deep. With successful pilots already under way, experts believe the technology is nearing real-world deployment.

By blending digital and environmental intelligence, Europe is proving that what happens below the surface can strengthen what happens above it. Soon, the same cables that carry our messages could also carry something more profound: a new understanding of the planet itself.