Teams from the GFZ Helmholtz Centre for Geosciences in Potsdam and the GEOMAR Helmholtz Centre for Ocean Research Kiel, both in Germany, are establishing infrastructure to monitor oceans via systems that use optical fiber. Funded with €30 million ($32 million) from the Helmholtz Association, the SMART Cables And Fiber-optic Sensing Amphibious Demonstrator (SAFAtor) project seeks to unlock previously inaccessible data on climate and geological hazards. The initial plan, according to the partners, is to equip a demonstrator with appropriate sensor technology before deploying it into the deep sea. The worldwide network of telecommunications cables lying on the bottom of the world's oceans offers distinct potential for scientific use if the fiber optic cables themselves are used or equipped with sensors. “There is a huge gap in our observational data, which makes it difficult for us to better understand the effects of climate change on the oceans or the causes of geological hazards like earthquakes, tsunamis, or volcano eruptions,” said Charlotte Krawczyk, director of the GFZ Department of Geophysics. “We want to close this gap with SAFAtor.” Telecommunication cables can be used as sensors (pink cable) or equipped with sensors (blue cable) both on land and in the sea and the deep sea, thus providing unique data for monitoring climate and natural hazards such as earthquakes, tsunamis, volcanic eruptions, and landslides. Courtesy of GFZ Helmholtz Centre for Geosciences/M. Dziggel. To this end, approximately 40 sensor stations will be attached to the cable before it is laid, at a distance of about 20 to 30 km, preferably at the repeater stations. These will continuously supply real-time data on temperature, pressure, and ground movement. It must be demonstrated that telecommunications traffic is not disrupted. Fiber optic cables equipped with intelligent sensor technology are also known as Science Monitoring and Reliable Telecommunications (SMART). “Telecommunications cables run across the oceans and have to be replaced every 25 years. If we use SMART cables for this, we will be able to achieve simple and comparatively inexpensive sensor coverage of the ocean floor and coastal areas,” said project coordinator Fabrice Cotton of the Helmholtz Association. Cotton also heads the European GeoINQUIRE project, which has initiated the first developments for disseminating this data to the scientific community. The exact route of the SAFAtor cable has not yet been determined. Possible regions worldwide are currently being explored, including the Mediterranean, the Arctic, and off New Zealand. The SAFAtor cable can then serve as a blueprint for future projects, thus advancing international initiatives that want to establish this measurement system on other cables by providing practical and scientific experience. In addition, permanent coastal monitoring is planned at three selected observatories: near the seismically active North Anatolian fault zone, which threatens the city of Istanbul; at Etna, one of the most active European volcanoes; and at the northern Chilean subduction zone, where strong earthquakes occur regularly. The fiber-optic measurement principle is used for coastal monitoring, in which the cable itself serves as a sensor. With this technology, the light pulses in individual glass fibers can be used to measure even the smallest ground movements, such as those triggered by earthquake waves. All newly acquired cable data will be made available centrally. To this end, a data service is being set up at the GFZ that will also serve as a platform for future cable data. The new data has the potential to significantly enhance the understanding of ocean currents and the role of the oceans in climate change. At the same time, the data will be useful to aid in the understanding of geological hazards like earthquakes, tsunamis, landslides, and volcanic eruptions, and significantly reduce early warning times for extreme events. In addition to these core applications, the data will also be used to study marine ecosystems. SAFAtor draws on the GFZ's many years of experience in operating global and regional observatories and in research data management of large data sets. The researchers at the GFZ will therefore be primarily responsible for the expansion of the observatories in the coastal area, but will also be involved in the selection and equipping of a demonstrator cable with SMART sensors. The GFZ will also provide the infrastructure to process and archive the newly acquired data and make it accessible. GEOMAR, with its expertise in the development of submarine technologies, will play a leading role in the integration of the necessary SMART sensor technology into deep-sea cables. The associated project partners — the Helmholtz centers Alfred Wegener Institute (AWI) and Hereon — are providing underwater infrastructure for development purposes. SAFAtor also receives broad national and international support from scientific consortia and institutes, industry, and network operators.