Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 1
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE Executive Summary Earth's oceans are essential to society as a source of food and minerals, a place of recreation, an economic means of transporting goods, and a keystone of our national security. Despite our reliance on the ocean and its resources, it remains a frontier for scientific exploration and discovery. Scientists have been using ships to explore the ocean with great success over the past 50 years and this mode of expeditionary science has led to remarkable increases in oceanographic knowledge. A ship-based expeditionary approach, however, is poorly suited for investigating changes in the ocean environment over extended intervals of time. To advance oceanographic science further, long time-series measurements of critical ocean parameters, such as those collected using seafloor observatories, are needed (NRC, 1998a). For the purpose of this report the term “sea observatories” is used to describe an unmanned system of instruments, sensors, and command modules connected either acoustically or via a seafloor junction box to a surface buoy or a fiber optic cable to land. These observatories will have power and communication capabilities and will provide support for spatially distributed sensing systems and mobile platforms. Instruments and sensors will have the potential to make measurements from above the air-sea interface to below the seafloor and will provide support for in situ manipulative experiments. In the fall of 1999, the National Science Foundation (NSF) asked the National Research Council (NRC) to investigate the scientific merit, technical requirements, and overall feasibility of establishing the infrastructure needed for a network of unmanned seafloor observatories. In addition, NSF asked the NRC to (1) assess the extent to which seafloor observatories will address future requirements for conducting multidisciplinary research in the oceans and (2) gauge the level of support for observatory science within the ocean
OCR for page 2
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE sciences and the broader scientific community. The NRC Committee on Seafloor Observatories was appointed to carry our this charge. The Committee's findings and recommendations are based on the knowledge and experience of Committee members, consideration of various reports and workshop documents, and input from the “Symposium on Seafloor Observatories” held in January 2000. The Committee concludes that seafloor observatories present a promising and in some cases essential new approach for advancing basic research in the oceans, and encourages NSF to move ahead with plans for a seafloor observatory program. Furthermore, based on written and verbal responses from the symposium, the Committee views the ocean and earth science community as being enthusiastic and supportive of seafloor observatory research. It should be noted that the strong multidisciplinary support for observatories is based on an observatory concept that encompasses a wide spectrum of facilities and substantial flexibility in their geographic positioning. An observatory system restricted to a single facility type or a discipline-specific geographic focus would not garner the same broad enthusiasm. The Committee also cautions that, although seafloor observatories provide a significant scientific opportunity, there are risks involved in this endeavor. Both potential benefits and risks are outlined in this report. The scientific benefit of seafloor observatory investigations has been recognized for many years and, as such, numerous independent national and international observatory efforts have been proposed or are underway. Many of these efforts are described here. Although the seafloor observatory program discussed in this report will be primarily research driven, the data collected by the proposed observatories will provide an important contribution to operational observing systems, such as the international Global Ocean Observing System (GOOS). SCIENTIFIC MERIT OF SEAFLOOR OBSERVATORIES Seafloor observatories could offer earth and ocean scientists unique new opportunities to study multiple, interrelated processes over timescales ranging from seconds to decades; to conduct comparative studies of regional processes and spatial characteristics; and to map whole-earth and basin-scale structures. The scientific problems driving the need for seafloor observatories are broad in scope, spanning nearly every major area of marine science. Many of these have been previously identified in the NSF long-range plan “Futures” reports (Baker and McNutt, 1996; Jumars and Hay, 1999; Mayer and Druffel, 1999; Royer and Young, 1999). Some of the most compelling of these scientific problems are discussed below.
OCR for page 3
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE ROLE OF THE OCEAN IN CLIMATE The ocean influences climate through processes that vary over regional (and smaller) scales, such as equatorial upwelling, western boundary circulation, subtropical subduction, and deep convection in high latitudes. These ocean circulation processes not only participate directly in climate variability through their influence on sea surface temperature but also affect the coupled ocean-atmosphere system through their influence on ocean biogeochemistry (e.g., the carbon cycle). To understand and potentially predict climate variations on longer timescales requires time-series measurements that resolve rapid processes, such as internal waves. A seafloor observatory network that provides globally distributed, fixed location time-series measurements of relevant surface and water-column properties would be an important contribution to a systematic approach toward climate research and prediction. FLUIDS AND LIFE IN THE OCEAN CRUST Although ocean chemistry is greatly influenced by the movement of fluids through oceanic crust, the processes controlling this flow are poorly understood. Recent studies on the nature of the subsurface biosphere have indicated that the crust contains a population of dormant microbes that are periodically driven into a population explosion by input of heat and volatiles into the crust during magma emplacement events. Time-series measurements of fluid movement near active ridgecrest vent fields, on ridge flanks, and at convergent margins will be critical for directly observing the changes in heat, chemical fluxes, and biological diversity produced by magmatic or tectonic events, and will form the basis for understanding how these changes influence global biogeochemical cycles. DYNAMICS OF OCEANIC LITHOSPHERE AND IMAGING EARTH'S INTERIOR Many of Earth's dynamic tectonic systems will be difficult to understand fully without a continuous observational presence provided by the establishment of seafloor observatories. These include the complex magmatic and tectonic systems operating at ridge crests and submarine volcanoes; the genesis of destructive earthquakes and tsunamis at subduction zone megathrusts and their relationships to large-scale plate motions, strain accumulation, fault evolution, and subsurface fluid flow; the geodynamics of Earth's interior and the origin of Earth's magnetic field; and the motion and internal deformation of lithospheric plates. Seafloor observatories also have the potential to play a key role in the global assessment and monitoring of geological hazards, as many of
OCR for page 4
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE Earth's most seismogenic areas and most active volcanoes occur along continental margins. COASTAL OCEAN PERTURBATION AND PROCESSES An important factor limiting coastal ocean research is the inability to quantify vertical and horizontal transport of water, elements, and energy through the coastal ocean system. Long time-series measurements of critical parameters, such as temperature, salinity, nutrients, and trace elements, will help provide the data needed to remedy this deficiency. Furthermore, anthropogenic influences are strongly felt in the coastal ocean through such effects as excess nutrient and contaminant inputs. It is difficult to assess the full impact of these inputs without being able to quantify the fates and transports of materials through the coastal zone. These transports are critical for the understanding of such factors as how the coastal ocean influences biogeochemical cycles and how turbulence in the coastal zone influences primary productivity. TURBULENT MIXING AND BIOPHYSICAL INTERACTIONS Successful modeling of the distribution of organisms and chemical compounds in the ocean depends directly on the predictive quality of circulation models, which are, in turn, limited by our ability to model turbulent mixing in the ocean. Because turbulent motions result from highly nonlinear dynamics acting across a range of time and space scales, from the dissipation scale of a few millimeters to mesoscale eddies with diameters of approximately 100 km, progress in understanding these motions is difficult. Continued advances will depend on the ability to systematically collect long-term measurements resolving small vertical and horizontal scales throughout the range of turbulent regimes that are controlled by extremes of mechanical forcing, buoyancy forcing, and topography. ECOSYSTEM DYNAMICS AND BIODIVERSITY The biological, ecological, and biogeochemical questions likely to benefit most from sustained ocean time-series observations are those involving time-dependent processes or episodically triggered events. Important time-dependent problems include population dynamics of predators and their prey; changes in fish stocks over time; and the effects of daily, seasonal, and lifecycle migrations of populations on biogeochemical processes. In addition to the observation of natural events and perturbations, it is anticipated that the ability to conduct active experiments, such as controlled releases of chemicals or tracers into the water column or manipulations of seafloor communities, will
OCR for page 5
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE be a beneficial outcome of observatory science. Furthermore, acquisition of long-term datasets is essential for documenting, understanding, and forecasting such processes as the effects of climate change on ecosystems, the long-term impact of human activities (e.g., nutrient loading, stock harvesting, introduction of exotic species) on marine populations, and the formation of barriers to genetic exchange that result in speciation. TECHNICAL FEASIBILITY AND REQUIREMENTS FOR SEAFLOOR OBSERVATORIES Relatively capable moored-buoy and cabled observatory systems are in use today, while the more complex systems that are needed should become feasible when sufficient engineering development resources are devoted to key infrastructure elements. CABLED SYSTEMS Cabled seafloor observatories will use undersea telecommunications cables to supply power, communications, and command and control capabilities to scientific monitoring equipment at nodes along the cabled system. Each node can support a range of devices that might include items such as an Autonomous Underwater Vehicle (AUV) docking station. Cabled systems will be the preferred approach when power and data telemetry requirements of an observatory node are high. Early generation commercial optical undersea cable systems that are soon to be retired will have the communications capacity to satisfy most anticipated observatory research needs, but will possibly have insufficient power capability. If these cables are suitably located for observatory research studies, their use could be explored to reduce the need for expensive new cable systems. As it is likely that cabled observatories would be installed at a site for a decade or more, substantial engineering development will be required in the design and packaging of the power conditioning, network management, and science experiment equipment. In order to meet the requirements for high system-operational time (versus downtime), low repair costs, and overall equipment lifetime, significant trade-offs will have to be considered between the use of commercially available and custom-built equipment. MOORED BUOYS Moored-buoy observatories consist of surface buoys acting as a central power generation and communications node, with a satellite or direct radio link to shore. This surface buoy is mechanically connected to the seafloor and communicates with instrument packages on the mooring line or on the seafloor
OCR for page 6
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE acoustically or via an electrical or fiber optic cable. In contrast to cabled observatories, moored-buoy systems are less expensive to install, but the trade-off is a greatly diminished communications bandwidth and reduced power availability. Buoy-based observatories are well suited for long-term observations in remote areas where cabled observatories are unavailable or are prohibitively expensive to install, and for studies of episodic processes or investigations that require observations for periods of months to several years from relocatable observatories. SHIPS AND REMOTELY OPERATED VEHICLES Ship and Remotely Operated Vehicle (ROV) capabilities suitable for installing and maintaining seafloor observatories currently exist in industry and within the University National Oceanographic Laboratory System (UNOLS) fleet. Specialized cable-laying and support vessels will be required to install cabled and large moored-buoy systems. For operation and most maintenance purposes, the Committee believes that one to two dedicated research vessels or workboats with ROVs will be required to support an observatory system consisting of approximately two dozen nodes. Considering the current stress on ROV availability, the Committee believes that present capabilities will have to be augmented to support a major seafloor observatory program. SCIENTIFIC INSTRUMENTATION While there are a wide variety of sensors currently available for undersea work, and there are many key instruments that are currently deployed for long time periods (such as , hydrophone arrays, and current meters), it is clear that development of new sensors will be critical for seafloor observatories to be fully effective. Sensor technology in many areas (e.g., chemistry and biology) is not sufficiently advanced to take substantial advantage of the proposed observatory infrastructure and many sensors will need considerable development before they can be expected to operate unattended for long periods of time in an observatory setting. If an ocean observatory infrastructure is to be established, a substantial parallel investment in sensor technology will be necessary. In addition, a seafloor observatory network should have the capability to incorporate visitor instruments that are dedicated to a specific experiment for a finite amount of time. AUTONOMOUS UNDERWATER VEHICLES AUVs provide the capability to move instruments from an observatory node to surrounding sites of interest, greatly expanding the region available for data collection. For example, AUVs can potentially undertake a variety of
OCR for page 7
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE mapping and sampling missions while using fixed observatory nodes to recharge batteries, offload data, and receive new instructions. Furthermore, as many oceanographic processes occur episodically in relatively localized regions, it often will be necessary to search for these sporadic events over a wider area. AUVs can provide this capability. Significant engineering advances will be required for AUVs to be routinely used at seafloor observatories, including the development of a reliable docking capability at the node and the capability to operate for extended periods (a year or more) without servicing. DATA PROCESSING, ARCHIVING, AND DISTRIBUTION Seafloor observatories will present a great opportunity to collect long time-series datasets, but a challenge to any observatory data management structure will be the processing, distributing, and archiving of the very large datasets produced. A fully integrated plan for data handling should be developed early in the planning stages for any seafloor observatory program. This plan should include provisions for making all data publicly available as early as possible. Data management support should be provided to science investigators; in return, science proposals must anticipate and address data management issues. In addition, financial support should be made available to principal investigators for the production of data products suitable for public distribution. A distributed data management system is desirable, in order to take advantage of existing data management facilities to the extent possible. BENEFITS AND RISKS OF ESTABLISHING A SEAFLOOR OBSERVATORY NETWORK The establishment of a network of seafloor observatories will represent a new direction in ocean science research, and one that will require a major investment of resources over many decades. Such a major commitment carries with it both potential benefits and risks: POTENTIAL BENEFITS The potential benefits associated with the establishment of a seafloor observatory program include: establishment of a foundation for new discoveries and major advances in the ocean sciences, by providing a means to carry out fundamental research on natural and human-induced change on timescales ranging from seconds to decades; advances in societally relevant areas of oceanographic research, such as marine biotechnology, the ocean's role in climate change, the evalua
OCR for page 8
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE tion of mineral and fishery resources, and the assessment and mitigation of natural hazards, such as earthquakes, tsunamis, and harmful algal blooms; improved access to oceanographic and geophysical data, enabling researchers anywhere in the world to study the oceans and earth in real-time or near real-time by providing basic observatory infrastructure with a wide variety of sensors; establishment of permanent observation sites over the 70 percent of Earth's surface covered by oceans, to provide truly global geophysical and oceanographic coverage not possible with observations limited to continental or island stations; development of new experimental approaches and observational strategies for studying the deep sea; enhancement of interdisciplinary research for improving the understanding of interactions between physical, biological, and chemical processes in the oceans; establishment of observational resources as fully funded facilities, with the use of and access to these facilities being determined by peer-reviewed proposals; and increased public awareness of the oceans through new educational opportunities for students at all levels, using seafloor observatories as a platform for public participation in real-time experiments. POTENTIAL RISKS The potential risks associated with the establishment of a seafloor observatory program include: installation of poorly designed and unreliable observatory systems if program and project planning and risk management are inadequate, technical expertise is lacking, and/or engineering development resources are insufficient; potential interference between experiments resulting from inadequate design, coordination, and/or testing of scientific instrumentation; inefficient use of resources if important technological questions are not adequately resolved before major investments in observatory infrastructure are made; possible compromise in system performance if critical technologies (e.g., satellite telemetry systems and development of some sensor types) driven by market forces outside the scientific community are not available when needed; the potential for a growing concentration of technical groups and expertise at a smaller number of institutions involved in supporting
OCR for page 9
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE the observatories, with the result that many students and scientists may become further removed from understanding how observations are made; unreasonable constraints on the freedom of individual investigators to choose the location and timing of their experiments; the potential for severe impacts on observatory science funding, and funding for other kinds of research and expeditionary science, if the cost of building, maintaining, and operating an observatory infrastructure is higher than initially estimated, and/or there is a catastrophic loss of observatory components; underuse of observatory infrastructure if insufficient funds are budgeted for supporting observatory-related science and the development of scientific instrumentation; and the potential inability of the present funding structure (based on peer-reviewed, 2- to 5-year duration, discipline-based grants) to judge the merit of projects requiring sustained time-series observations over many years or decades, and/or projects that are highly interdisciplinary. RECOMMENDATIONS Based on a detailed consideration of the potential benefits and risks that might be associated with a seafloor observatory program, the Committee makes the following recommendations. NSF should move forward with the planning and implementation of a seafloor observatory program. Seafloor observatories represent a promising approach for advancing basic research in the earth and ocean sciences and for addressing societally important issues. The establishment of a major seafloor observatory program will require some philosophical and intellectual reorientation within the oceanographic community, building on and complementing the more traditional focus on ship-based mapping and sampling programs. It will also require a major new commitment of resources. Based on the limited information available to the Committee, it is estimated that the initial cost of establishing a seafloor observatory infrastructure could eventually approach several hundred million dollars, and the cost of operating and maintaining this system could be several tens of millions of dollars annually. Thus, seafloor observatories may ultimately require a level of support comparable to that of the present academic research fleet. An investment of this size must be approached cautiously. In addition, mechanisms need to be put in place to deal with contingencies that arise (NRC, 1999) during the establishment of a seafloor observatory network.
OCR for page 10
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE A comprehensive seafloor observatory program should include both cabled and moored-buoy systems. Moored-buoy systems should include both relatively high-power, high-bandwidth buoys and simpler, lower-power, limited-bandwidth buoys. The diverse applications for seafloor observatory science require the use of both cabled and moored-buoy observatories. Thus, the development of both systems should proceed in parallel. Because of the scientific need to study transient events, it is also important that rapidly deployable (within weeks or months) observatory systems be developed. The first step in establishing a seafloor observatory system should be the development of a detailed, comprehensive program and project implementation plan, with review by knowledgeable, independent experts. Program management should strive to incorporate the best features of previous and current large programs in the earth, ocean, and planetary sciences. The development of a program and project implementation plan should include a comprehensive definition of the management and science advisory structure for an observatory program, an implementation timeline and task list with specific milestones, a funding profile for the program, and a schedule for periodic review of program planning and implementation efforts by knowledgeable, independent experts. The management structure must ensure fair and equitable access to observatory infrastructure and must also provide information concerning such issues as protocols and engineering requirements for attaching instruments to a node. The requirements of a management and operational structure for a seafloor observatory program are likely to be similar to other large, coordinated programs in the earth, ocean, and planetary sciences (e.g., UNOLS, JOIDES/ODP,1 UCAR/NCAR,2 IRIS,3 and NASA4 mission structures), and the most successful features of these structures should be adopted. 1 JOIDES - Joint Oceanographic Institutions for Deep Earth Sampling; ODP - Ocean Drilling Program 2 UCAR - University Corporation for Atmospheric Research; NCAR - National Center for Atmospheric Research 3 IRIS - Incorporated Research Institutions for Seismology 4 NASA - National Aeronautic and Space Administration
OCR for page 11
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE A phased implementation strategy should be developed, with adequate prototyping and testing, before deployment of seafloor observatories on a large scale because of the cost, complexity, and technical challenges associated with the establishment of these systems. Great care is needed in the design and implementation of seafloor observatories if they are to meet their scientific potential. Observatory networks should start with simpler nodes, adding more complex nodes and configurations over time. This growth plan will allow lessons learned from early deployments to be factored into the design of the later, more complex systems. As such, consideration should be given to the establishment of one or more pilot observatory sites to test prototype systems and sensors in areas that are readily accessible by ships and ROVs. A certified testing capability is also needed to test instrumentation and identify possible interference problems. The engineering development of some component systems that will be part of the initial pilot observatories (such as power and communications systems, AUVs, and sensor technology) could occur in parallel with the establishment of a program and project implementation plan. This will prevent delays in the establishment of initial pilot observatory needs. A seafloor observatory program should include funding for three essential elements: basic observatory infrastructure, development of new sensor and AUV technology, and scientific research using seafloor observatory data. Advances in sensor and AUV development must proceed in parallel with the development, design, manufacture, and installation of basic observatory infrastructure. The development of biological and chemical sensors and instrumentation for long-term in situ measurements is a particularly high priority. AUV development is important because these vehicles will provide the means to greatly expand the footprint of a fixed observatory node by undertaking a variety of mapping and sampling missions around the node. There will be no benefit to the existence of seafloor observatories unless scientists are using them to advance our knowledge and understanding of the oceans. Funding for infrastructure and sensors must be balanced with funding for excellent peer-reviewed science that takes advantage of the unique capabilities of observatories. There will still be many important scientific problems that are best addressed using traditional ship-based techniques or fleets of drifters or floats. It is essential, therefore, that a seafloor observatory program be only one component of a much broader ocean research strategy.
OCR for page 12
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE New mechanisms should be developed for the evaluation and funding of science proposals requiring sustained time-series observations over many years or decades and for proposals that are highly interdisciplinary. Support for observatory-related science will pose new challenges for such funding agencies as NSF. Observatory proposals will typically be more interdisciplinary and will require funding over longer time periods than is currently the norm. The NSF program and review structure is currently not well structured to handle these kinds of proposals, and NSF is taking steps to remedy this problem through increased cooperation and cooperative review of interdisciplinary proposals among program units. This deficiency was highlighted in the NRC report Global Ocean Science: Toward an Integrated Approach, which proposed the creation of a new unit within the Research Section of the NSF Ocean Sciences Division that would be charged with managing a broad spectrum of interdisciplinary projects (NRC, 1999). A mechanism should be developed to transition successful instrumentation developed by an individual scientist to a community asset. The development of mechanisms to support and encourage the transition of new instrumentation and technology from successful prototype to supported elements of the observatory infrastructure provides a major challenge both for funding agencies and the scientific community. NSF has an excellent track record of funding individual investigators to develop new instrumentation, but turning this instrumentation into a community asset has not been easy. The fundamental problem is to take an instrument that is successful in the hands of the developer and to make it successful in the hands of the broader community. Such a transition may impose significant demands beyond those an individual investigator would normally undertake, for example, reengineering elements of the system for non-expert use, production of systems in quantity, and operational support of fielded systems. The importance of operational support can be understood by considering a straightforward Conductivity, Temperature, and Depth (CTD) capability, which requires a trained and experienced operator base despite the commercial availability of CTD hardware. Involvement of industry through existing mechanisms, such as the Small Business Innovation Research (SBIR) program, although clearly important, does not address the fundamental need of providing mechanisms for extending infrastructure support to appropriate new systems. Since the observatory can be characterized as an extension of our network and power infrastructure into the ocean, with the goal of supporting diverse oceanographic instruments, mechanisms for making such instruments widely available must be an integral part of the plan.
OCR for page 13
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE An active public outreach and education program (including kindergarten to twelfth grade [K-12]) should be a high-priority component of a seafloor observatory program, with a specified percentage of program funding dedicated to this effort. Seafloor observatories with real-time communication capabilities will offer an excellent opportunity for public outreach and innovative education initiatives at all levels. With real-time data links to deep sea instruments, it will be possible to involve students and the public directly in ocean science. However, the educational and public outreach potential of seafloor observatories can only be realized by making a meaningful financial commitment to support the development of new ways to present and interpret data for the nonscientific public. To ensure that this effort is made, a percentage of program funding should be provided for outreach and every science proposal should be given a financial incentive to encourage participation in education and public outreach activities. This financial commitment should be drawn from public, private, and industry sources. A seafloor observatory program should have an open data policy, and resources should be committed to support information centers for archiving observatory data, generating useable data products, and disseminating information to the general public. Routine (facility-generated) information products and data should be archived in a central facility and be made available in as near real-time as possible to all investigators and the general public, ideally through the Internet. Data from experimental sensors or individual investigator-initiated experiments should be made publicly available after quality control procedures have been applied, but within 1 to 2 years of retrieval. A distributed data management system is desirable and, to the extent possible, existing data management facilities should be used (NRC, 1999). Seafloor observatory programs in the United States should be coordinated with similar international efforts to the extent that progress in the U.S. program is not inhibited. In addition, the Committee recommends that the potential of an integrated, international observatory program be explored. The goals of a seafloor observatory program in the United States are closely linked to a number of ongoing national and international initiatives, such as GEOSCOPE and the International Ocean Network. Where practical, coordination of these efforts at the international level will be beneficial and in
OCR for page 14
Illuminating the Hidden Planet: THE FUTURE OF SEAFLOOR OBSERVATORY SCIENCE some cases essential. Some major scientific objectives (e.g., global seismic coverage) will be achievable only through this kind of global cooperation. The vision of establishing a global network of seafloor observatories holds tremendous promise for advancing our understanding of Earth and its oceans. The Committee recognizes that realizing this vision will be difficult and expensive, but based on examination of the important scientific questions that remain to be answered and the current state of technology, the Committee believes the time has come to take the first concrete steps.
Representative terms from entire chapter: