Undersea Cables Become Ocean Sensors: Monitoring Currents and Climate

Scientists have ingeniously repurposed existing transatlantic fiber-optic cables as ocean sensors, developing a new instrument that measures subtle changes in light signals to monitor water temperature and pressure. Without disrupting their primary function, the system uses reflections from repeaters spaced every 50-100 kilometers along the cable to measure variations in light travel time, inferring data such as daily and weekly water temperature and tide patterns. This groundbreaking research offers a cost-effective way to monitor the ocean environment, improving our understanding of ocean currents, climate change, and natural hazards like tsunamis.