The UK’s National Physical Laboratory (NPL) and their partners say that the cables could be used as deep sea scientific sensors, helping to sense earthquakes, tsunamis, or see how climate change alters the currents.
This has already been tested by scientists through the use of a cable connecting the UK and Canada. This is being tested because installing sensors to monitor the ocean floor can be very costly and very difficult, and for that reason only very few of such sensors exist. Using subsea internet cables would be more cost effective.
Theres an estimated 430 of these cables, spanning over 800,000 miles, providing good coverage from country to country. Vibration, pressure, and temperature changes can slightly affect the speed that the light is travelling through these cables, which could be detected. As scientists could detect waves through the link from the UK to Canada, the same same could be done for the other cables around the world, providing a great coverage of underwater sensors. Theres also a potential, untested yet, possibility to sense the temperature change in the ocean due to climate change.
Overall, the ability to sense earthquakes, tsunamis, and other factors at such close range would be very beneficial, as it provides the possibility to have more time to prepare for such events, and with preparation damage and more importantly casualties could be limited.
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