The vast and dense undersea network of cables that offer internet to the world can also be used to monitor seismic activity. In fact, one of these cables has already detected an earthquake, thereby proving the technology works.
The world’s seas and oceans are massive, and worryingly, the majority of the area underwater is still not actively monitored. With just a few dedicated sensors, there’s still a huge shortfall of regularly updated geophysical data. This could change due to a new breakthrough.
A recently published paper claims a new method turns the undersea telecommunications cables into an array of sensors. The team behind the innovation even proved the technology could detect earthquakes and other mundane oceanic activities such as waves and currents.
The technique we present has the potential to transform our Earth-monitoring capabilities. The seafloor could be instrumented with thousands of [such] sensors without modifying the existing submarine telecommunication infrastructure.
The team was referring to sections of an undersea cable formed due to amplifiers and repeaters. Almost all the cables currently laid on the ocean floor have these instruments that ensure data streams have enough energy to traverse safely and reliably. These repeaters are located every 28 to 56 miles (45 to 90 km) along the length of a cable. They separate the cables into shorter “spans”. The team relied on these individual spans between repeaters spread across the entire transatlantic connection.
The method, if or when deployed globally, could offer thousands of permanent real-time environmental sensors on the ocean floor using preexisting hardware. Assimilating the new method with preexistent seismometer-based networks would greatly expand the global earthquake-monitoring infrastructure.
It is interesting to note that the innovation does not require any alterations or additions to the underwater infrastructure. This makes the solution extremely affordable, scalable, and quickly deployable.
The team is confident that they could even expand their technology to monitor and understand other natural phenomena such as deep-water flows, long-term seafloor temperature changes, and so on. Such uses are possible due to the high sensitivity of the optical-fiber cable.
Scientists have always fought a losing war against the huge upfront investment needed to deploy sensors that monitor climate. However, the new innovation could easily contribute to building long-term and accurate climate models at fraction of the usual costs.