A multidisciplinary ocean observatory system for the North Atlantic and Southern Ocean: B-DEOS

Adam Schultz and the B-DEOS Consortium

Abstract:

A consortium of research groups and institutions within the United Kingdom and supported by planning input scientists from six other countries is planning a system of multidisciplinary ocean observatories in the N Atlantic, and Southern Ocean to study the linkages between the physical, chemical and biological processes regulating the earth-ocean-atmosphere-biosphere system. An engineering study has been completed that has resulted in a design for the a mooring and telecommunications/power buoy system that will enable continuous, medium-bandwidth, bi-directional telemetry to/from shore, command/control of remote instruments from the scientists desktop, public involvement and education related to the operation of the observatory system, and generation and transmission of electrical power from the sea surface, through the water column, and to an adaptable junction box on the seafloor. A large-scale "Thematic Programme" is in the advanced planning stage within the United Kingdom's Natural Environment Research Council. A staged programme of coastal system testing, followed by large-scale installation of the first deep water site has been proposed. The first deep water observatory installation is to take place across a 400 km wide (E-W) by 50 km (N-S) area centred on the Mid-Atlantic Ridge near the Lucky Strike segment south of the Azores. This is the "MOMAR" observatory area. Installation of the MOMAR observatory system has been called for in numerous InterRidge planning documents, as well as in Expressions of Interest that had been submitted to the European Commission under the Framework 6 funding model. It is hoped that the B-DEOS Site 1 - MOMAR - will form the nucleus around which a permanent pan-European and international observatory will develop. Site 1 is to be operated for five years in the first instance.
Pending approval of the funding plan by the UK NERC, following two years of operations at Site 1, Site 2 will be established, centred on the southernmost Reykjanes Ridge south of Iceland. After several years of
simultaneous observations, and pending successful outcomes from operation of the first two sites, a third large-scale observing system is proposed for the Southern Ocean. This will extend from the area of
the Drake Passage between Cape Horn and the Antarctic Peninsula, eastward over the Scotia Plate and extending to the South Sandwich Islands. The first generation of trans-Atlantic and trans-Pacific
fibre-optic telecommunications cables are presently being decommissioned. B-DEOS is working with Iris Ocean Cable Inc in the US, and has initiated contacts with other European partners to evaluate the
possibility of using such cables in situ, or to relocate cable sections.
In the first case TAT-8,9,10,11 cross the Mid-Atlantic Ridge at latitudes spanning 40-45 degrees N. Some sections of one or more of these cables could be cut and relocated to establish a robust Southern
Ocean observatory system. Others could be operated in place to study a variety of processes in the north Atlantic that have been specified in the B-DEOS science plan. Further details are available on www.deos.org.

ARENA : A Versatile and Multidisciplinary Scientific Submarine Cable Network of Next Generation

Yuichi Shirasaki, Minoru Yoshida, Takato Nishida, Katsuyoshi Kawaguchi and Kenichi Asakawa

Abstract:

Recently, noble technologies such as optical amplifier and wavelength division multiplex technology for underwater telecommunication cables and Ethernet emerged and evolved rapidly. Internet technology also enables us to develop a versatile data network connecting the cabled observatories and the related researchers. These noble technologies enable us to develop a flexible and versatile scientific submarine cable network of next generation. Moreover existing cabled observation systems show us the their versatility and possibility.

A technical committee organized by IEEE OES (Institute of Electrical and Electronics Engineers Oceanic Engineering Society) have done a feasibility study on the scientific underwater cable network and proposed a future scientific submarine cable network and its possibility.

The proposed scientific submarine cable network covers vast research area and enables long-term continuous and precise monitoring and will enable the development of new science. Combined with AUVs and in-site sensors in underwater boreholes, they are expected to provide us new knowledge on deep sea and earth.

The cable network has the following feature. (1) mesh-like cable network configuration, (2) more than 3,000km total cable length, (3) over 66 observation node with 50km interval, (4)multi-disciplinary application field, (5) high cost/performance, (6) reliable backbone system, (7) robust against failures, (7) exchangeability of sensors.

The feasibility study was conducted by three working groups, those are (1) underwater system architecture, construction and maintenance technology, (2) data transmission and management technology, and (3) power feeding technology. In this paper the outline of the feasibility study will be presented. The details will be presented in the accompanied papers.

ASSEM : A new concept of regional observatory

J. BLANDIN , R. PERSON, J.M. STROUT, P. BRIOLE, G. ETIOPE, M. MASSON, S. SMOLDERS, V. LYKOUSIS, G. FERENTINOS and J. LEGRAND

Abstract:

Continental margins are the focus of increasing human activities which are moving towards deeper waters. Some of these margins are also areas where drastic phenomena like slope failures may occur. There is a need to better understand the phenomena leading to these instabilities by measuring geotechnical, geodetic or chemical parameters related to sediment and seafloor.
The ASSEM project consists in developing the optimised means to measure and monitor a set of geotechnical, geodesic and chemical parameters distributed on a seabed area in order to better understand the slope instabilities phenomena, to assess and possibly predict the associated risks. Within the ASSEM project, equipments are developped in order to deploy a selection of adapted sensors on a seabed area (few square km) and transmit their data in real time to shore for exploitation.
To achieve these objectives, ASSEM targets the achievement of several innovations:
ß A detailed pre deployment site survey in order to choose the best sites for the deployment of sensors;
ß A controlled deployment of sensors and stations by ROV or manned submersible;
ß A modular design with standard connecting and installation interfaces allowing to easily adapt the system to the site of interest, add new sensors, and replace components for maintenance;
ß A two-way communication link between sensors and shore, built on an acoustic network or wired links;
ß A local storage of all the raw data in each node with local analysis capabilities able to generate alarms;
ß Enhanced sensors for long term monitoring.

An array is composed of several nodes. Each node includes an electronic unit, named COSTOF (COmmunication and STOrage Front-end), providing a set of enhanced sensors (pore pressure, methane, geodesy, tilmeter, CTD, turbidity, currents,) with capabilities to communicate with the external world through an underwater network, and to locally store the collected data. Alarms can also be generated by processing these data. The architecture is organised around an internal CAN/CAN open bus hosting both sensors, communication and data storage resources on a common transmission backbone. All the modules connected to the bus include the same "kernel" card and a specific extension card. Each "kernel" card includes a Atmega129L processor, a 512Kbytes flash memory, a real time clock and 2 RS232 links. The software resources enabling a monitoring node to act as a network node (routing algorithms throughout the network, network configuration management, data transmission protocol and other network layers) are implemented in every COSTOF unit. Alarms can be generated for example if a critical parameter, or a group of parameters, comes above a programmed threshold for a given time. This distributed architecture allows to configure very easily a Monitoring Node and to add new function without modifying the existing functions.

The same modularity concept is applied to the mechanical design. The deployment and the maintenance of the node imply a submersible or a ROV. Protection against trawling are used with the acoustic transmitter installed in a special flexible mast.
The acoustic network is developed from a new version of the MATS 12 acoustic modem produced by ORCA instrumentation. This digital modem based on micro-controller and DSP cards, is capable of data transmission under adverse channel conditions at data rates up to 2400 bits per second (bps). Original network protocols, with autonomous handshaking and adaptive bit rate, adaptive modulation and adaptive routing were implemented. Such a network offers much more reliable and much higher data rate links than available modems. Directional transducers were developed to decrease power consumption.
Pore pressure is an important parameter for the modifications of the soil before and during a geohazard event. It will be measured at several levels, in bore holes down to 200m, and in tubes of CPT probes inserted in the sediment down to 30m.
The natural occurrence and emission of gas on the sea floor (methane seeps) are increasingly recognised as an important marine process for its environmental and geohazard implications. A methane sensor from CAPSUM is adapted for long term deployment (antifouling membrane, self calibration capability) and deeper capability.
In tectonically active areas, ground deformation sensors are claimed but under sea, geodesy is still in its infancy. Different sensors are developed and tested : a long range taut wire distancemeter (NGI), an acoustic distancemeter (IPGP) and a high accuracy pressure gauge.
The measurement of temperature, salinity, turbidity, current, static and dynamic water pressure is necessary in conjunction with pore pressure, gas sensors and geodesic sensors.
In ASSEM project, two complementary pilot experiments are planned. The first one will be conducted at a site showing risk of slope instability, in the North Sea off Norway. The experiment will include hook-up of integrated pore pressure sensors installed in bore-holes and installation of standard sensor interface and communication system for data transfer to the surface.
The second experiment will take place in the Gulf of Corinth. The shelf, slope and margin of the basin off the coast of a faulted area is selected for the deployment of the ASSEM array of sensors. It is the most active extensional basin in Europe, with high rates of margin uplift. The array will be deployed in the south of Trizonia island and will host a seismometer satellite of the EC-ORION system, demonstrating the compatibility between the two systems.
Data collected in real time or immediatly after recovery of storage devices, will be made available to end users by internet. Results from EC project EMEW for the data handling of warning systems will be applied, especially for the Corinth experiment.

ASSEM is a new concept of real time sea floor observatories dedicated to collect data with low sampling rate when acoustic links are used, and presenting a high level of modularity. For higher sampling rate, wired link are available. It is also a warning system. It can be operated alone or linked to another observatory system, such as GEOSTAR/ORION. This concept could be applied to other long term studies in biology, biodiversity and environmental studies.

ESONET- European Sea Floor Observatory Network

Imants G. PRIEDE, Martin SOLAN, Jürgen MIENERT, Roland PERSON, Tjeerd .C.E.VAN WEERING, Olaf PFANNKUCHE, Nick O'NEILL, Anastasios TSELEPIDES, Laurenz THOMSEN, Paolo FAVALI, Francesco GASPARONI, Nevio ZITELLINI, Claude MILLOT, Hans W. GERBER, Jorge M.A. DE MIRANDA and Michael KLAGES

Abstract:

ESONET proposes a network of sea floor observatories around the European Ocean Margin from the Arctic Ocean to the Black Sea for strategic long term monitoring as part of the European GMES (Global Monitoring for Environment and Security) with capability in geophysics, geotechnics, chemistry, biochemistry, oceanography, biology and fisheries. Long-term data collection and alarm capability in the event of hazards (e.g. earthquakes) will be considered. Nine initial areas for ESONET development have been identified and an emergency response capability with mobile stations is proposed.

History of and Current Plans for U.S. Scientific Cabled Observatories for Time Series

Scott M. Glenn, Tommy D. Dickey, Oscar M. Schofield

Abstract:

Sustained ocean observing systems hold the promise of revolutionizing ocean related science within this decade. Enabled by technological advances and further fueled by societal need, a wide range of ocean and earth observing systems are being planned, proposed, deployed and operated. Both envisioned and existing observation systems emphasize real-time datasets for event response and adaptive sampling, well-sampled spatial and temporal contexts for limited-duration or process-study experiments, and sustained operation to observe long-term trends and capture rare episodic events. Collaborative science is similarly emphasized, with the widespread availability of increasingly multi-disciplinary datasets stimulating previously unfeasible cross-correlation analyses in the search for new associations or causal relationships. Extensive observations are increasingly being used in combination with interdisciplinary models through growing model development, coupling, validation and assimilation activities. The rapidly expanding observation and modeling capabilities are enabling scientists to consider an entirely new set of interdisciplinary science questions. In turn, the new questions can be used to guide and prioritize implementation strategies for upgrading existing, and deploying new, observatories.
The Scientific Cabled Observatories for Time Series (SCOTS) report is a significant part of the implementation process for one specific type of ocean observatory. It documents community input on the scientific questions best served by regional networks of the cabled observatories in three targeted domains - the open ocean, geologic plates, and coastal. The report is directed primarily toward those charged with the development of observatory implementation plans that address the priority science.
This talk will report on both of these efforts, first by summarizing the experience of existing U.S. cabled observatories, and second by outlining the prioritized science plans.

Infrastructure for the Modification and Maintenance of Legacy Undersea Systems

Arthur Ayres

Abstract:

The use of legacy undersea telecommunications cables for scientific applications requires a specialized capability to recover, modify and reinstall the in-water cable plant and reactivate the shore terminus. The telecommunications companies and their support infrastructure have abandoned the analog cables leaving the scientific community to look elsewhere for support, or to provide their own solutions. The undersea training systems used by the U.S. and other Navies has used these legacy cables for their systems. A typical range system has a service life in excess of 20 years and requires some level of service. The contractors responsible for the design, manufacture and installation of these systems have maintained capabilities for repair and modification for SD, SF and other analog cable based systems. Cost effective installation and recovery is based on a ship of opportunity approach. Materials and services are available for cable jointing including strength member and dielectric reconstitution for all types of both SD and SF cables, cable termination, repeaters, demultiplexers and system power.

Permanent Full Wave Subsea Seismic Monitoring Systems Provides Next Generation of Applications for Oil and Gas Reservoir Exploration, Geotechnical Engineering and Security Monitoring Industries

Harold Merry and Larry Walter

Abstract:

In recent years there has been much interest in permanently installed high-resolution full-wave ocean bottom or seafloor seismic recording. Utilizing a full-wave or four-component sensor which includes a hydrophone (measures pressure) sensor and a three-axis geophone sensor (measures velocity in three dimensions) provides the ability for continuous dynamic seismic monitoring on the sea floor. These new systems provide a new generation of applications including high resolution oil and gas reservoir characterization, seabed subsidence, microseismic and macro-earthquake monitoring and security monitoring for harbor infrastructures.
All components of these new systems are designed and built for long-term reliability to with stand the rigors of deploying and operating in high pressure deep water environments. State-of-the-art distributed subsea digital electronics, high-speed fiber optic telemetry, full-wave sensors, high-strength armored subsea cabling, wet and dry mate-able connectors, high capacity real-time data recording are now commercially available in the industry.
Most importantly, the subsea system needs to be custom designed to cost effectively fit the size and shape of the reservoir and accommodate for sea floor infrastructure such as communication cables, anchors, production pipelines, etc.
One such system displayed presently being installed is to be used for high definition oil and gas reservoir characterization enabling the production engineer to dynamically monitor the oil and gas drainage in the reservoir continuously. The system consists of more than one hundred and twenty-five linear kilometers of contiguous armored sensor cables and over ten thousand channels of seismic data recording designed to operate in up to two thousand, five hundred meters of water.

Physical Oceanography from Deep Ocean Submarine Cable Observatories

Dr. Douglas S. Luther

Abstract:

Some of the important discoveries in physical oceanography that have been based on data acquired at "observatories" far from the coasts will be reviewed, e.g., the interannual variability of Labrador Sea Water formation inferred from Ocean Weather Ship Bravo data. These discoveries motivate the need for additional long duration physical oceanographic measurements in the deep ocean, as can be acquired from submarine cable observatories, and they provide guidance on the spatial and temporal sampling requirements needed to reach the next level of discoveries. Instrumentation developed in the last ten years, such as moored velocity and water property profilers, that can enhance the scientific return on investments in cabled observatories will also be reviewed. Additional technological enhancements that would be highly desirable for observatory-based instrumentation for physical oceanography will be discussed.

Scientific Re-use of Retired Undersea Fiber Optic Telecommunications Cables

Rhett Butler

Abstract:

The first generation of fiber optic undersea telecommunications cables that span the North Pacific and Atlantic Oceans are now being retired. Three are in the Pacific: Hawaii-4 (California-Hawaii), TransPacific Cable-3 (TPC-3 Hawaii-Guam+Japan), GPT (Guam-Philippines-Taiwan). Four are in the Atlantic: TransAtlantic-8 (TAT-8 NewJersey-UK+France), TAT-9 (NewJersey +Canada-UK+France+Spain), TAT-10 (RhodeIsland-Germany), and TAT-11 (NewJersey-UK+France). The systems are being retired 10-15 years early, because newer generation systems are so much faster and upgradeable that maintaining these ÔslowerÕ systems is not economical for the telecommunications companies. However, there is now an extraordinary opportunity for re-using these systems for science. These first generation systems contain one to three fiber pairs, with each pair supporting communications at 296 Mb/s, or for TAT-9, -10, and ­11 at 592 Mb/s. The systems operate at 1.7 amps and 7 kvolt, and about 5 kwatts of power are available for a seafloor observatory system. There are a number of ways that these systems may be re-used. Observatories may be installed along the current cable route. It is possible to recover and re-lay sections of these cable systems with a cable ship to locations more advantageous for science. The transfer of coaxial telephone systems in the 1990sÑthe Hawaii-2 from AT&T and sections of the TransPacific Cable-1 and ­2 systems from AT&T and KDDÑto the scientific community through IRIS and the University of Tokyo has shown the challenges and successes that cabled observatories on the seafloor offer science. The Hawaii-2 Observatory (H2O) between Hawaii and California has provided years of high-quality real-time data from the seafloor. These newly retiring fiber optic telecommunications cables offer far greater opportunities for the scientific community.

Seafloor Geodesy and an Ocean Bottom Cable System

Hiromi Fujimoto

Abstract:

Japanese Islands lie in subduction zones, and most of big earthquakes in and around Japan occur under the seafloor. The GPS network on land (GEONET) has revolutionized the geodeticÅ@monitoring of crustal deformation on land. DistÅ@ribution of seismic coupling in the subduction zone has also been estimated from land-based observation of GPS (Nishimura et al., 2000) or seismicity (Igarashi, 2001). However, the deformation on land is much smaller than that on the seafloor, and the Japan trench axis is about 200 km offshore. Therefore, deformation in the seismogenic zone, especially in the shallower region, is weakly constrained from the observations on land. For the back-slip modeling, the plate motion of the Pacific plate at the subduction zone is assumed to be constant, but there has been no observational constraint on the assumption.
Importance of crustal movement on the seafloor has been pointed out for long time, and at last the dream is coming true. Chadwell et al. (2002) have recently reported results of GPS/Acoustic seafloor positioning suggesting episodic spreading of the Juan de Fuca ridge. Results of repeated acoustic ranging (Nagaya et al., 1999) and ocean bottom pressure monitoring (Fujimoto et al., 2003) for 14 months across the axis of the super-fast spreading southern East Pacific Rise suggests thermal contraction of the crust in the spreading center in the inter-eruption period.
Another important point is that theoretical and experimental studies suggest a small slip on a fault plane before the main rupture of the fault. There are several important reports on anomalous crustal deformations before inter-plate earthquakes. Such a pre-slip is crucial for the study of earthquake prediction. Real time or semi-real time monitoring on the seafloor is indispensable to detect such a crustal deformation. An ocean bottom cable system has become important for seafloor geodesy.
Because a pre-slip before an earthquake is estimated fairly small, high sensitivity is necessary for the monitoring system. A tiltmeter and a strainmeter like those installed in the downholes of JT1 and JT2 on the landward slope of the Japan trench are the most probable instruments for the moment. Ocean bottom pressure recorders can be used for the monitoring of a vertical crustal movement. Although it is difficult from the viewpoints of engineering and costs, a GPS/Acoustic system combined with a surface buoy enables long-term and real time monitoring of seafloor positions on the seafloor.

Sensor networks for cabled ocean observatories

Bruce M. Howe, Timothy McGinnis, Harold Kirkham, Gene Massion

Abstract:

This paper considers the development of a support infrastructure for subsea observatory sensors and networks. Some sensors will be self-contained individual items, others will be part of a sensor network using, for example, secondary cables and junction boxes to extend the horizontal reach 10s to 100s of km from backbone nodes, or using moorings to distribute observatory capabilities throughout the water column and (equivalently) down boreholes into the crust. Included in the support infrastructure could be acoustic navigation and communications systems, free-swimming AUVs, and bottom rovers that could carry sensors and could provide data and energy "tanker" service. Because of the likely long term observatory application of sensors, and the high cost of access, methods of self-calibration of sensors will also be useful.

The sensor infrastructure would supplement the observatory infrastructure that is part of the US NSF Ocean Observatories Initiative (OOI) and other programs as well. This Initiative plans to provide junction box nodes on the seafloor that furnish power and communications, and distribute time. There are three elements of the OOI: a regional scale cabled observatory (such as NEPTUNE) with dozens of nodes; a sparse global array of buoys with seafloor nodes; and an expanded system of coastal observatories. Each of these observatories will depend on suites of sensors from a number of investigators, and it is likely that once the observatory infrastructure itself has been installed and commissioned, most of the physical interaction with an observatory will be for installing, operating, servicing, and recovering sensors. These activities will be supported by the proposed infrastructure, enabling the full potential of the observatory

SMAPS : Super-Precision Mapping for Crustal Monitoring

Paul Jubinski and Donald M. Hussong

Abstract:

The need to plan safe routes for submarine cables has spawned a survey industry that uses towed vehicles to generate highly-detailed (1 meter depth contour) bathymetric maps. Particularly useful for planning operations involving cable burial plows, these maps are routinely produced now for water depths as great as 1,800 meters. For special applications, such as route planning for deep-water pipelines, towed vehicles are used to produce similar bathymetric maps in water depths exceeding 3,000 meters. However, as the water depth increases, the technical challenges and the costs of these surveys increase rapidly.

Autonomous underwater vehicles (AUVs) are now being designed and constructed for survey operations in water depths exceeding 3,000 meters. Although expensive to own, these vehicles offer a precision maneuvering capability and can safely operate at altitudes only one tenth the minimum altitudes required by towed vehicles at comparable depths. Equipped with appropriate geophysical mapping instruments, AUVs could be used to generate decimeter depth contours even in the deep ocean.

Acquiring decimeter-accuracy bathymetric data also demands decimeter-accuracy vehicle positioning data in three dimensions, which has not previously been achievable for survey areas in deep water or very far from shore. But progress is being made and the improvements in wide-bandwidth acoustic ranging systems, precision dual-frequency GPS, compact inertial navigation platforms, doppler velocity sensors and seafloor pressure monitoring stations are showing great promise. It will soon be possible to use AUVs to generate bathymetric maps with 10 centimeter accuracy even in very deep water.

In Japan, the residents of the Island of Honshu live with the knowledge that they may be affected by devastating earthquakes that occur every few decades. As part of a larger study of the seismogenic zone east of Honshu, the SMAPS Project intends to map the seafloor at decimeter accuracy over an area extending from Kumano-nada down into the Nankai Trough. In addition to giving an unprecedented look at a large area of the convergent margin, follow-on surveys in subsequent years should indicate how the crustal material is responding to the tectonic forces. Ultimately, the goal of the project is to build up a detailed understanding of the mechanisms by which strain is accumulated and released in this area so that some predictive capability can be developed.

System Engineering for a Regional Scale Cabled Observatory, Process and Progress

Gene Massion, Pat Beauchamp, Alan Chave, Tim McGinnis, Peter Phibbs, Dave Rogers

Abstract:

Scientific submarine cabled observing systems are changing and will continue to change our understanding of ocean processes by offering unprecedented opportunities for ocean science research, education and outreach. To approach the full potential cabled observatories can provide, an effective System Engineering process is required. This paper will describe the tools, techniques and processes used in the System Engineering effort coordinating an international group of projects designing a regional scale observatory. The goal of this observatory is to provide a new generation observing infrastructure for 4D (3 spatial and 1 temporal) current and future state of the art ocean science research. The infrastructure will support observation of processes with spatial scales from micro to tectonic plate scale, from the air sea interface through the water column to the benthos and time scales from microseconds to decades. In order to accomplish these ambitious goals, a novel system is being designed that transitions state of the art terrestrial technologies to the submarine environment. The current baseline design provides an 8 Gbit/second data network, a power network capable of providing up to 10 kW of power to 30+ science nodes distributed over 3500+ km of cable. In addition, the observatory provides the critical instrument control, timing signals and data management functionality required to ensure PIs located around the globe can get potentially huge volumes of useful data from 100s of instruments on the observatory across the internet to their laboratories. The major subsystems include a data network, power network, command and control network, time distribution, shore stations, ocean engineering, science instrument interface as well as data management and archiving. This paper will describe the process and progress we have made in developing functional requirements, trade studies to evaluate various system concepts, identifying and addressing risky elements and ensuring the subsystems work together as an optimal system to meet the functional requirements. Particular attention has been paid to developing a set of tools to analyze and optimize the reliability of the system. We will also describe the System Engineering process we are planning to proceed from our current preliminary design state through detailed design, fabrication, test, deployment and operation.

The Ocean Observatories Initiative: Cabled Observatories for Ocean Research

H.L. Clark and A.R. Isern

Abstract:

Global processes that actively shape the earth and ultimately impact society must be investigated over the spatial and temporal scales at which they occur. To characterize the temporal behavior of dynamic processes occurring in the ocean, new types of infrastructure are needed that are capable of providing long-term, high-resolution observations of critical environmental parameters. NSF's Ocean Sciences Division plans to initiate construction of an integrated observatory network to provide the oceanographic research and education communities with new modes of access to the ocean. The Ocean Observatories Initiative (OOI) has three elements: a regional cabled network, several deep-sea buoys, and new or enhanced facilities leading to an expanded network of coastal observatories. In addition to the regional cabled network to be constructed, it efforts to utilize recommissioned seafloor telecommunication cables as ocean observing sites will continue.

Thirty years ago, NSF leadership helped establish the system of support for the U.S academic research fleet of modern vessels, that is accessible to all investigators. In the same manner, this initiative will start building a network of ocean observatories that will facilitate the collection of long time-series data streams needed to understand the dynamics of biological, chemical, geological and physical processes. The new observational capabilities will have significant impacts upon the ocean research community by providing the means to carry out fundamental research on natural and human-induced change on timescales ranging from seconds to decades. This system will also establish the foundation for new discoveries and major advances in ocean science. The scientific problems driving the need for an ocean observing system are broad in scope and encompass nearly every area of ocean science: Ecological characterizations, The Role of the Ocean in Climate, Fluids, chemistry, and life in the oceanic crust, Dynamics of the Oceanic Lithosphere and Imaging the Earth's Interior, Seafloor Spreading and Subduction, Organic Carbon Fluxes, Turbulent Mixing and Biophysical Interaction, Coastal Ocean Processes, Real-Time Regional Modeling and Forecasting.

The exciting scientific discoveries arising from the OOI will provide new opportunities for ocean education and outreach through the capabilities for real-time data transmission and, particularly, real-time display of visual images from the seafloor. Because of the broad impact of the OOI on education and training, from conception to conclusion, this initiative will be a source of inspiration and innovation through the combination of cutting-edge technology and research to study the complex interactions of processes on, above, and below the seafloor.

VENUS: The New Science of Cabled Observatories

Richard K. Dewey and Verena Tunnicliffe

Abstract:

The Victoria Experimental Network Under the Sea (VENUS) is a cabled seafloor observatory under construction in the coastal waters between Vancouver and Victoria, BC. Scientific instruments under the surface and on the sea floor will connect directly to a data distribution centre and to the computers of scientists via the internet. The observatory cables will provide electrical power and interactive communication for a variety of instruments and sensors.
Synoptic, multidisciplinary ocean observations will be available in real time to scientists, resource managers, educators, and the public.
In the past, most ocean observations have been conducted from research vessels scheduled months to years in advance, using instruments deployed for relatively short periods. Analysis of the in situ measurements is conducted later, back in the laboratory, once the instruments have been recovered.
Often, important oceanic phenomena are missed due to the stochastic nature of marine variability. With a permanent observatory, ocean scientists will, for the first time, have direct access to their instruments for observing the ocean, adjusting the sampling strategy, and responding to detected events.
The initial installation of VENUS will include a basic suite of instruments
for sampling a variety of fundamental oceanic parameters.
These sensors suites include: i) a limited number of major bottom packages to measure water properties (Temperature and Salinity, T&S), currents, acoustics, seismometry, and optical backscatter, ii) more numerous shoe-box nodes measuring just T&S and background acoustics, iii) two vertical profilers which will measure the vertical distribution of T&S, currents, turbulence, plankton, and video imagery, iv) a delta suite for monitoring slope stability and sediment dynamics, including seismicity, strain, T&S, currents, bottom stress, turbulence, acoustic backscatter, and scanning sonar, and v) a benthic community response suite to observe the benthic ecosystem using particle
analyzers, respirometry, currents, and video imagery.
The observatory's main purpose is to support ocean research in one of most complex coastal environments. The initial instrument suites will allow researchers to study estuarine exchange circulations, delta sediment dynamics, plankton behaviour, ocean turbulence, whale communication patterns and seafloor communities, among many other possibilities. Future expansion of the observatory could include surface and wave studies, autonomous vehicle surveys, and the assimilation of in situ 24/7 data into regional numerical models.

A Multidisciplinary Deep Sea Long-Term Observatory in Japan (P)

Dr. Andrew M. Clark and Hiroyuki Sekino

Abstract:

Described is an effort to deploy off the coast of Japan, a system designed to collect and transmit data from the deep sea floor, sensors placed in boreholes, as well as water column and air-sea interface sensors and transmit this data back to shore in real-time. A variety of sea floor and buoy based sensors provide oceanographic, atmospheric and geophysical data. Transmission of high-speed data (to 2 Mbps) is effected by means of a moored surface buoy that is tethered to the sea floor by a cable carrying both optical fibers and copper power conductors. The data link to shore is facilitated by an inertially stabilized and steered C-Band antenna pointed at a geosynchronous satellite. Redundant 20kW diesel generators onboard the 5-m diameter buoy both power this telemetry system and supply up to 1 kW of electrical power to seafloor sensors. This Ocean Net buoy, designed by Harris Corporation, carries on board sufficient fuel and electronic redundancy to support 6 months of unmanned operation. Areas around Japan are regions particularly well suited for such a high bandwidth observatory. Broadband seismometers, strain gauges and other sensors deployed in nearby boreholes, drilled to study seismogenic zones, provide vital data for the for scientific community. The mooring riser of the surface buoy is terminated at a sea floor Junction Box equipped with ROV-wet-mateable connectors. These connectors facilitate the continual addition of future sensors and experiments. The bandwidth facilitated by the optical fibers and C-Band satellite link, along with the power transmitted down the riser, is sufficient to support sea floor video and lights, thereby enabling visual observations to be posted on the Internet. This observatory has been planned and designed in conjunction with Japan Drilling Co., Ltd. Other partners and collaborators are being sought to add additional sensors and dimensions to this multidisciplinary observatory.

Scientific Application of ARENA Networks (P)

Junzo Kasahara, Yuichi Shirasaki, Kenichi Asakawa and Katsuyoshi Kawaguchi

Abstract:

A new scientific submarine cable network named ARENA (Advanced Real-Time Earth monitoring Network in the Area) will be planed to encircle Japanese Island and cross several tectonic plates in Japan.
ARENA network will provide researchers a long-term, real-time, wide-bandwidth infrastructure for multidisciplinary seafloor observation in the deep sea to explore problems unapproachable with existing methods. This observatory network consists of many observation nodes with 50km intervals, and each node is connected with many kinds of sensor for studies within a wide spectrum of scientific field and for the disaster-related measures to earthquake, tsunami and volcano.
This paper will describe new observation ideas using ARENA has been discussed at the committee organized by Research Institute for Ocean Economics and JAMSTEC.