Axial Seamount - wired and restless: A cabled submarine network enables real-time, tracking of a Mid-Ocean Ridge eruption and live video of an active hydrothermal system Juan de Fuca Ridge, NE Pacific

The most scientifically diverse and technologically advanced component of the National Science Foundations' $386M investment in the Ocean Observatories Initiative (OOI), involves 900 kilometers of high power and bandwidth electro-optical cable extending from Pacific City, OR, across active portions of the Juan de Fuca tectonic plate and up into the overlying ocean. Completed on time and under budget in October, 2014, this mesoscale fiber-optic sensor array enables real-time, high-bandwidth, 2-way communication with seafloor and water-column sensor networks across: 1) a portion of the global Mid-Ocean Ridge (MOR), 2) a section of the Cascadia Subduction Zone, and, 3) a cross-section of the California Current, a component of the North Pacific Gyre. Much of the data generated from >130 fiber-linked instruments has become available for scientific, educational and public user communities over the past 6 to 12 months, via the OOI Cyber-infrastructure (http://oceanobservatories.org/data-portal/). Since the OOI Cabled System has been in use and streaming live data to shore, two major developments have emerged that bear on undersea volcano-hydrothermal systems: 1) The 2015 submarine eruption of Axial Seamount was documented in a unique fashion by 20 remote, hardwired instruments distributed across the floor of the summit caldera. 2) Live, streaming video of an active hydrothermal system within one of the vent fields inside the caldera reveals subtle changes taking place in the Axial system.