The NEPTUNE Canada Regional Cabled Ocean Observatory. Basetnlps: Pro;ectiOn:UTMZ9NWGS&4

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1 The NEPTUNE Canada Regional Cabled Ocean Observatory An Overview of the Progress of Installation And the Design of the Science Experiments By Dr. Chris R. Barnes Project Director Dr. Mairi M.R. Best Associate Director of Science NEPTUNE Canada University of Victoria and Dr. Adam Zielinski Professor Department of Electrical and Computer Engineering University of Victoria Victoria, Canada The North-East Pacific Time-Series Undersea Networked Experiments (NEPTUNE)Canada will be the world's first multi-node regional cabled ocean observatory.this innovative network of five subseaobservatorieswill be linked by 800 kilometers of powered electrooptic cable acrossthe northern Juan de Fucatectonic plate. By about 2014, the u.s. portion will be installed, also comprising five observatory nodes, so that both networks combined will span the Juan de Fuca Plate (200,000 square kilometers). Hundreds of sensors will be located on the seafloor in boreholes and buoyed in the water column. Remotelyoperatedvehicles (ROVs)will resideat depth, powered at observatory nodes and directed from distant labs. Continuous near-real-time multidisciplinary measurementserieswill extend for more than 25 years.the initial data flow of 50 terabytes per year will be managed through a Web servicesenvironment. The many researchthemes addressed by NEPTUNE Canada will include structure and seismic behavior of the ocean crust; dynamics of hot and cold 10 sf / JULY2008 Basetnlps: usgs Open File No.9i-368 Pro;ectiOn:UTMZ9NWGS&4 NEPTUNE Canada cable route showing node locations (with depths) and the Port Alberni shore station, extending west of Vancouver Island. fluids and gas hydrates in the upper ocean crust and overlying sediments; ocean and climate change and effects on ocean biota and fisheries at all depths; deep-sea sedimentation, ecosystem dynamics and biodiversity; and engineering and computational systems research. These involve interacting processes, long-term changes and chaotic, episodic events that are difficult to study and quantify by traditional means. The NEPTUNECanada observatory has collaborated closely with the Victoria Experimental Network Under the Sea (VENUS) and Monterey Accelerated Research System (MARS) ocean observatoriesand will use similar cable and engineering systems.the NEPTUNECanada and VENUS observatories, within Ocean Networks Canada,will form a linked coastaland regional cabled ocean observatorysystem, among the first of many being planned (i.e., Japan, Taiwan, Western Europe,China). Planning and Installation NEPTUNECanada representsa consortium of 12 Canadian universities (Memorial, Dalhousie, Rimouski, Laval, Universite du Quebec a Montreal, Toronto, Guelph, Waterloo, Manitoba, Simon Fraser, University of British Columbia and Victoria), led by the

2 . I., I:., == II., "., ".- (Above) ROV-serviceable node, similar to those used by NEPTUNE Canada, lowered into a trawl-resistant frame manufactured by L-3 Communications MariPro at the MARS observatory and the Monterey Bay Aquarium Research Institute. (Photo courtesy of L-3 Communications.) (RighV A vertical profiler (400 meters) will be located near Barkley Canyon, manufactured by NGK Ocean. University of Victoria (UVic). Under the terms of the major funding awards, UVic must both own and operate the observatory,and it hasdevelopedspace on campus for the operations and data center for NEPTUNE Canada and VENUS. In 2005, UVic contracted with New Southgate, England-based Alcatel Submarine Networks (ASN) to design, manufacture and install the wet plant infrastructure (cable and nodes). Subcontractors include Texcel Technology (Crayford, England), L-3 Communications MariPro (Goleta, California) and Alcatel-Lucent Canada (Markham, Canada). Ocean Works International (North Vancouver, Canada) is building the junction boxes, and Tokyo,Japan-based Nichiyu Giken Kogyo Co. Ltd. (NGK Ocean) is making the 400-meter vertical profiler for the Barkley Canyon site. The 800-kilometer cable loop from UVic's shore station at Port Alberni, Canada, out to Endeavour Ridge will include five instrumented observatory nodes located at coastal FolgerPassage; slope sites of ocean.drilling program (ODP) 889 and Barkley Canyon; a midplate, abyssalplain ODP 1027 site; and an ocean spreading site at the Endeavoursegmentof the Juande Fuca Ridge. A sixth node will be established at Middle Valley (a sedimented portion of the Juan de Fuca Ridge) with future funding. ASN designed, manufactured and installed the cable with the repeaters, branching units and spur cablesover 11 weeks in fall The nodes will be installed by ASN from May to June 2009, followed by deployment of the secondary cables, junction boxes and instruments by JULY2008 / sf 11

3 NEPTUNE Canada. Final commissioning is expected in late Experiments and Instrumentation The approved community science experiments, using several hundred sensors, will focus on the study of hydrothermal systems on the Juan de Fuca Ridge,gas hydratesoutcropping in Barkley Canyon and in the subsurface at ODP 889, the coupling between physical and biological systems off Vancouver Island, the dynamics of deep-sea benthic ecosystems, the inshore physical and biological oceanography near BarkleySound and the hydrologic regime in the oceanic crust and tsunami monitoring at site ODP Hydrothermal Systems. The Endeavour team will deploy instruments at two of five vent fields on the Endeavoursegment of the Juan de Fuca Ridge, at Main Endeavour Field and Mothra. These include temperature resistivity probes, microbial incubators, high-resolution digital cameras and McLane (Falmouth, Massachusetts) fluid samplers. A regional circulation experiment sf I JULY2008 designed to characterize hydrothermally driven water mass movement will have four mooring arrays extending 250 meters into the water column. Instrumentation will consist of acoustic 3D current meters situated at 10, 50, 125 and 250 meters above the seafloor. With each current meter, a sensor will measure temperature and salinity variations. One bottom-pressure sensor will measure local tides. Refurbishment and redeployment of the University of Washington's shortperiod seismometers at Endeavour will permit continuation of the time series of seismic observations. Deployment of a broadband seismometer will allow for the characterization of overall seismicity and examination of linkages between local tectonics and biological and oceanographic phenomena. A bottom-pressure recorder deployed near Endeavour Ridge is part of the tsunami-monitoring network. Gas Hydrate. Various instruments deployed near the known outcropping of gas hydrates along the northwest wall of Barkley Canyon will record accretion and degradation of hydrate mound structures, as well as changes in biological and chemical activity. Sensors will include in-situ temperature probes at depths of one meter or more, three rotary still cameras and a crawler developed at Jacobs University, in Bremen, Germany. The latter will carry a conductivity-temperature-depth recorder (CTD), a methane sensor, a Schlieren optical system, a Webcam to control vehicle movements, a video system to quantify gas bubbles and, possibly, oxygen sensors or a benthic flow simulation chamber to study particle dynamics. Biophysical Linkages, Shelf Slope. A water column experiment will develop a better understanding of the coupling between the physics and the biology off the southwest of Vancouver Island, relating this coupling to variability in oceanographic processes and responding to long-term climate change. Instrumentation will consist of a 400- meter water column profiler, located on the continental slope eight kilometers north of Barkley Canyon. This profiler, equipped with acto, oxygen sensor, fluorometer, transmissometer, nitrate sensor, carbon dioxide sensor, multifrequency acoustics package and upwelling/downwelling radiometer, will acquire profiles of water properties through the entire water column. Bottom-mounted instruments will consist of an upward-looking 150-kilohertz acoustic Doppler current profiler (ADCP) and pressure sensor. Deep-Sea Benthic Ecosystems. A benthic ecology experiment in the highly productive area near Barkley Canyon, characterized by seasonal upwelling, will interface with the water column team. It will examine changes in benthic communities related to transfer of energy and nutrients from the water column to the seafloor, as well as through the canyon. Equipment deployed at four separate sites along northwest Barkley Canyon and within the axis will investigate downslope sediment transfer. One instrument pod will be located near the vertical profiler. Instrumentation will consist of acoustic current meters,sedimenttraps, rotary sonar systems, plankton pumps, video cameras, high-resolution still cameras, a CTD with fluorometer, a microbial metabolic sensor package and a laser optical plankton counter. A

4 hydrophone deployed near the canyon should detect both slope failures and marine mammals. Coastal Oceanography. The Folger Passagesite, located in Barkley Sound, 10 kilometers west of Bamfield Marine Science Centre, will consist of two installations, one at 95 meters' water depth and another near the summit of a rocky pinnacle in 15 meters of water. Overall objectives are to identify factors that control biological productivity, both within the water column and at the seafloor; to evaluate the effects of marine processes on fish and marine mammals; and to provide learning opportunities for students, researchers and the public. The deepwater instrument package will consist of an ADCp,multifrequency bioacoustic sensor, oxygen sensorand temperature/salinity sensor. A hydrophone will detect and characterize marine mammals. Instrumentson the pinnacle will include a 3D camera array to examine the responseof rocky reef organisms to environmental variability, upward and downward-looking high-frequency ADCPs and a light sensor. The Folger Passagesite will be complementary to the water column site on the continental slope at 400 meters' water depth, where the vertical profiler will collect a variety of water property and biological data. Tsunamis-Seismicity. At site ODP 1027 on the abyssal plain in 2,660 meters' water depth, existing ocean drilling program borehole monitoring systemswill be connected to the observatory. Two circulation obviation retrofit kits (CORKs)were placed in 1996 and an additional two in Two CORKs will be connected. The holes extend tens to hundreds of meters into the igneous seafloor through a sediment cover of a few hundred meters. Objectives are to monitor changes in crustal temperature and pressure, particularly asthey relate to eventssuch as earthquakes, hydrothermal convection or regional plate strain. A 10-kilometer triangular array of very sensitive bottom-pressure recorders will function as part of a tsunami array of bottom-pressure recorders and will determine openocean tsunami amplitude, propagation direction and speed.this tsunami array will complement data from buoy sensorsand coastal tide gaugesaround the North Pacific and contribute to knowledge of tsunami (and other large wave) behavior, as well as provide real-time monitoring of the phenomena. Nearby at the Baby Bareigneousoutcrop, a broadband seismometer with associated hydrophone and a singlepoint current meter will be deployed. Baby Bare exhibits slow fluid venting from the seafloor and may prove of great interest in the study of biota located within this broad expanse of flat abyssalplain sediments. Gas Hydrates. SiteODP 889 is located on the continental slope in about 1,250 meters of water in a widely studied area characterized by shallowly buried gashydrates. Initially, most instruments deployed in the Bull's Eye area will consist of suites of geophysical instruments, including a controlled source electromagnetic system and receiver, seafloor compliance system (gravimeter) and geophone array. The objective is to monitor changes in hydrate distribution, depth, structure r I ] JULY2008 / sf 13

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