Ocean Observing using SMART subsea telecommunications cable systems

Abstract:

Planning is underway to integrate ocean sensors into SMART subsea cable systems providing basin and ultimately global array coverage within the next decades (SMART: Scientific Monitoring And Reliable Telecommunications). SMART cables will: contribute to the understanding of ocean dynamics and climate; improve knowledge of earthquakes and forecasting of tsunamis; and complement and enhance existing satellite and in-situ observing systems. SMART cables will be a first order addition to the ocean observing system, with unique contributions, strengthening and complementing satellite and in situ systems. Cables spanning the ocean basins with repeaters every ~50 km will host sensors/mini-observatories, providing power and real-time communications. The current global infrastructure of commercial submarine telecommunications cable systems consists of 1 Gm of cable with ~20,000 repeaters (to boost optical signals); the overall system is refreshed and expanded on time scales of 10 – 20 years and individual systems have lifetimes in excess of 25 years. Initial instrumentation of the cables with bottom temperature, pressure and acceleration sensors will provide unique information for monitoring and studying climate change and for improved tsunami and earthquake warning. These systems will be a new highly reliable, long-lived component of the ocean observing system, complementing satellite, float and other in situ platforms and measurements. Several UN agencies, the International Telecommunication Union, the World Meteorological Organization, and the UNESCO Intergovernmental Oceanographic Commission have formed a Joint Task Force to move this concept to fruition (ITU/WMO/IOC JTF; http://www.itu.int/en/ITU-T/climatechange/task-force-sc). A review of the overall planning effort and two NASA-funded workshops focusing on the ocean circulation and climate is presented. [Funding provided by NASA.]