Optical interferometry-based array of seafloor environmental sensors using a transoceanic submarine cable

Optical fiber-based sensing technology can drastically improve Earth observations by enabling the use of existing submarine communication cables as seafloor sensors. Previous interferometric and polarizationbased techniques demonstrated environmental sensing over cable lengths up to 10,500 kilometers. However, measurements were limited to the integrated changes over the entire length of the cable. We demonstrate the detection of earthquakes and ocean signals on individual spans between repeaters of a 5860-kilometer-long transatlantic cable rather than the whole cable. By applying this technique to the existing undersea communication cables, which have a repeater-to-repeater span length of 45 to 90 kilometers, the largely unmonitored ocean floor could be instrumented with thousands of permanent real-time environmental sensors without changes to the underwater infrastructure.

Automated summary

Optical fiber-based sensing technology can utilize existing submarine communication cables as seafloor sensors to detect earthquakes and ocean signals. This technique allows for the installation of numerous real-time environmental sensors on the undersea cables without the need for changes to the underwater infrastructure.