DESCEND '99

Proceedings

To download a copy of the DESCEND Report, click here

vExecutive Summary

vI. Background

vII. Science Sessions

vIII. Technical Sessions

vIV. Infrastructure and Funding

vV.  Key Recommendations

vTable I

vAppendix I:   Summary of Specific Technological Recommendations

vAppendix II:  Meeting Agenda

vAppendix III: Steering Committee

vAppendix IV:  Workshop Participants

vAppendix V: Abstracts submitted by Participants

vAppendix VI: Related Website Links

Comments or Questions?

office@unols.org

photo by Craig Cary
October 25-27, 1999
National Science Foundation
Arlington, VA

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UNOLS Workshop 
Executive Summary

Discovering the Oceans

DESCEND

DEveloping Submergence SCiencE for the Next Decade

 

The Executive Summary of the DESCEND Workshop has been published into an 8-page brochure.  The brochure can be downloaded by clicking on “Executive Summary” below.  Copies of the brochure can be obtained from the UNOLS Office, office@unols.org.

 

Discovering the Oceans

DESCEND

Executive Summary

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DESCEND Meeting Proceedings

DEveloping Submergence SCiencE for the Next Decade

DESCEND

Steering Committee:
Keir Becker, University of Miami
Jim Bellingham, MBARI
Craig Cary, Univ. Delaware
Patty Fryer, Chair, Univ. Hawaii
Lisa Levin, SIO
Marv Lilley, PMEL

I. Background

    The DESCEND workshop, held on October 25-27, 1999 in Arlington, VA, was prompted by the need to define both the critical scientific goals for the submergence community and the technological directions that will be required to take submergence research into new realms of discovery in the coming decades.

    In order to accomplish its goals the DESCEND Workshop involved both scientists and technology experts. The scientists utilized creatively the face-to-face interaction with the engineers and technicians to articulate the types of research that will need new tools and innovative technological approaches in submergence science. The attendees were charged to think in terms of (1) multidisciplinary and multi-institutional use of multi-purpose platforms distributed globally and (2) in terms of developing infrastructure and specialized tools as appropriate for particular initiatives.

    The spectrum of scientific problems and environments that must be investigated require access to a broad scope of ocean environments with a range of safe, reliable, multi-faceted, high-resolution vehicles, sensors and samplers operated from support ships with global reach and station-keeping capabilities in all weather. The marine science community requires the right complement of deep submergence vehicles and versatile support ships from which they can operate. The attendees agree that submersibles, which provide the cognitive presence of humans and heavy payload capabilities, will be critical to future observational, time-series, and observatory-based research in the coming decades. Fiber-optic-based remotely-operated vehicles (ROVs) and tethered systems, especially when used in closely-timed, nested investigations offer unparalleled maneuverability, mapping and sampling capabilities with long bottom times and without the limitation of human/vehicle endurance. The community strongly encourages development of autonomous underwater vehicles (AUVs) of various designs to provide unprecedented access to the global ocean, deep ocean and sea floor without dedicated support from a surface ship.

    There are serious impediments to funding for multi-disciplinary science and for global, time-series, or long-term observatory work. Education of the public, our fellow scientists and assisting the funding agencies in education of the appropriate science advisory groups with regard to the advances in and potential from submergence research will be critical to implementing the recommendations from this workshop.

    Follow-up to this workshop, by both the deep submergence community and federal agencies is also a critical component to the future success and health of deep submergence facilities and science in the US. The funding agencies have discussed the possibility for a follow-up engineering and technology workshop to discuss details of the priorities of technology research and development that have been recommended at this meeting.

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II.  Science Sessions

The workshop science sessions were based on the types of environments in which submergence science is pursued, i.e., mid-ocean ridge environments, the abyss and open ocean, plate margin environments, polar and coastal regions. The objectives were to 1) define the critical scientific research themes to be emphasized in the next decade, 2) to specify the scientific questions to be addressed and to define strategies needed to approach answers to these questions, and 3) to define what technological approaches are needed to carry out these objectives. The objective is to help to direct future strategies for upgrades to vehicles, science sensors, sampling techniques, and imaging capabilities of submersible vehicle systems funded by the federal agencies.
 

A. Mid-Ocean Ridge Processes.

There are a host of fundamental, interdisciplinary questions requiring deep submergence technology that need to be answered in order to understand the Earth’s complex geochemical, biological and geological processes at mid-ocean ridges.

The Biosphere. The biological, chemical and physical processes that have controlled the origin and development of life on Earth can be studied in situ in the ocean crust and upper mantle beneath the global mid-ocean ridge system.

Crustal Architecture. Mid-ocean ridges are the locus of the Earth's greatest mass, chemical, and energy fluxes from the deep interior to the surface; as such, they provide the best windows into their associated processes. The magmatism and tectonism that create oceanic crust are neither steady state nor periodic nor well understood.

Active Cyclic Processes. The entire volume of the world oceans is cycled through hydrothermal vents at mid-ocean ridges every few thousands years. The oceanic crust represents the fundamental reaction zone between the ocean and the deep mantle, yet we still do not understand how it interacts with chemical and biologic processes along ridges.

Global Variability.

The Mantle Connection. Ultimately it is the heat, volatiles and silicate melts derived from the mantle that drive the magmatic, hydrothermal and biologic processes at ridge crests. Understanding the way in which magma melts and flows beneath ridges to form basaltic magmas is a main goal that can be addressed indirectly through submergence research.

INVESTIGATIVE APPROACHES

    We must be able to map and sample, from the seafloor and at depths, at all appropriate scales, to document the extent and diversity of biological communities and to define crustal architecture and maturation. Delicate biological samples must be obtained with precision-controlled manipulators and the samples must be protected from contamination. In situ monitoring of biological communities both at the seafloor and down-hole will be required. Near-bottom magnetic, gravity electromagnetic surveys, and active and passive seismic studies will help to define interrelations between tectonic forcing functions and biological and chemical processes.

    The study of cyclic processes will require event response sampling of lava, biota and vent/plume fluids, as well as sustained time-series observations. We must anticipate events and map and instrument likely sites. Such activities could be accomplished in the future with a fleet of AUVs that can be air-dropped in a region that has a navigation net in place. Development of sensors will be a critical component of this effort. Optimally, we will deploy extensiometers, tiltmeters, heatflow and geodetic devices, chemical monitors, and seismometers at likely sites of activity in order to monitor cyclicity of various processes.

    To address questions regarding global variability we must be able to optimize locating vents therefore we must improve spatial coverage. One way to do this would be to develop smart AUV (e.g., instruments that can detect various water properties). To gain wider spatial coverage we could look toward piggy-backing AUVs on other cruises. The critical need is to map the ridge and near-ridge geology and obtain representative surface and subsurface sampling over segment-scale and larger regions.

    To address questions regarding the mantle connection to ridge processes we must establish long-term seafloor observatories that are capable of monitoring a variety of chemical and physical processes. We must accomplish surface and subsurface sampling on a segment scale and engage in sampling for comparison along several segments. This will require detailed sampling by submersible or ROV and the capability to drill multiple holes in ridge environments.
 

B.  The Abyss and Open Ocean

    The abyss and open ocean host a complex network of interrelated physical, biological, chemical, and geological systems, often difficult to identify and understand because they are spread out over large volumes and are dynamic over time scales of minutes to millennia.

Mapping the Abyss and Open Ocean. The open ocean hosts one of the largest ecosystems on Earth, but the life cycles, spatial and temporal distribution of organisms remains largely unknown.

Quantifying the Dynamics of Abyssal and Open Ocean Systems. This field includes studying fluxes (in and out), changes in storage of energy and mass, reactions and interactions between components of abyssal and open ocean systems (chemical, physical, biological, geological), and studying the importance of variations over many time scales.

Understanding the Natural History, Behavior, Ecology, and Evolution of Abyssal and Open Ocean Communities. Fundamental questions concerning abyssal and open ocean biological communities revolve around their composition and variability, and the linkages which govern their abundance. Spatial and temporal variability of biological systems appears to be higher than for physical parameters of the ocean.

INVESTIGATIVE APPROACHES

    Mapping the abyss and open ocean regions will require both existing and yet-to-be-developed sensors on submersibles, ROVs and AUV platforms that give not only a three-dimensional view of sea floor topography, water column particulate matter and chemical properties, and the distribution of organisms but provide the ability to document the 4-D changes over time. Temporal variations in these processes are key to undertstanding them and their importance. Acoustic, photographic and laser line-scan imaging of water column and seabed features can be done in a nested mapping approach as has been done in ridge crest research. A similar nested scheme will need to be developed for mapping of organisms within the water column. Repeat surveys will provide the necessary temporal dimension.Permanent ocean bottom observatories such as those proposed under several initiatives are planned to be general-purpose observatories available to the community for installation of diverse experiments. Such stations will supply fixed sites for long time-series observations of geophysical, biological, chemical and physical oceanographic parameters over decadal time frames.

    Quantifying the dynamics ofabyssal and water column processes could take advantage of existing and new chemical sensors that can be deployed on ROVs and AUVs. Since chemical, biochemical and genome-based sensors are becoming smaller and are requiring less power, there will be an increasing demand to place them on AUVs and ROVs. These instrumented submergence platforms in conjunction with acoustic, photographic and laser line-scan imaging will result in a capability for an unprecedented dynamic view of physical, chemical and biological events and processes in the sea. This in turn will lead to obligatory changes in the need for modeling, data management and infrastructure support.

    Detailed chemical sampling at particle layers and physical discontinuities will be needed. The mid-water column and seafloor organisms must be sampled and their behavior observed. Manipulative ecological experiments will be required. We must quantify biota in the water column and on the seafloor. The ranges and rates of activity of these organisms and the interactions among them will have to be defined. We must measure or infer rates of fluid flow over broad areas and with depth within the seafloor. We must quantify the mid-water processing of surface ocean biomass during its descent to the seafloor, including the role of anoxic/suboxic microzones within the oxic water column.

    In-situ experiments and measurements are necessary to resolve time scales of forcing and responses. Sampling and monitoring rates will also need to be adjusted depending on interest in continuous or pulsed inputs, and will need to occur simultaneously over large areas in order to resolve regional-scale processes.

    Although remote sensing can be used to resolve near-surface processes at most time and space scales of interest, we lack a similar capacity for the remainder of the water column and seafloor, and any new methods developed for this purpose will need to be extensively verified and calibrated for accuracy.

    Addressing questions regarding the natural history, behavior, ecology, and evolution of abyssal and open ocean communities requires a broad new range of capabilities. Existing vehicle assets are not well suited to studying the mid-water environment in the oceans. Communities may be diffuse, consequently to obtain statistically significant population estimates, a key measurement for the studies outlined above, we must be able to search large volumes of water and large areas of seafloor. This observation capability must be backed up by an ability to detect and identify organisms, ideally autonomously. Sampling and collecting capability is also a requirement, especially the ability to acquire many samples per dive. To establish the context for more intensive experiments with mobile assets, work should be coordinated with deployment of equipment designed to obtain time-series data and samples. Access using both fixed and mobile platforms will be required.

    The huge data sets will be not only of numerical character but will also consist of images. There is a need to establish a data management infrastructure that minimally catalogs the metadata and ideally compiles a distributed database. Meta-databases indicating the availability of such information will be useful.
 

C. Margins

    The active and passive margins of tectonic plates and continental masses present the full range of ocean depths from a few meters in estuaries and coasts to >10 km in deep-sea trenches. Margins also differ characteristically by latitude. At high latitudes there are shelf depressions, fords, and abyssal flood plains whereas low latitudes have carbonate platforms, reefs, and the world's steepest and tallest escarpments. Mid-latitudes have coastal deltas, slope gullies and canyons, and the deep-sea fans with their successions of meandering channels. Margins have extraordinarily high biological productivity and among the greatest human population densities. They are the Earth’s principle loci for production of hydrocarbon and metal resources, as well as earthquake, landslide, volcanic and climate hazards. Extreme environmental conditions are prevalent. Margins have the highest organic loading, lowest oxygen levels and the strongest currents. Escaping fluids can range from alkaline to hypersaline, from the lowest to the highest pH recorded on Earth. Margins are the regions where most major fisheries are centered, the areas where human impacts are greatest, and where known species diversity is highest. Major oceanographic features such as boundary currents and oxygen minimum zones often impinge on continental margins. Despite the scientific, societal, and economic importance of margins, many of the mechanical, fluid, chemical and biological processes that shape them, and the way that margins shape ocean life, are poorly known.

Origins of the Continents, Oceans, and Life. Subduction zones are the birthplaces of continents and are the recycling factories of the earth. Ore deposits, volcaniclastic sedimentation, and submarine calderas are among the principal continent-forming phenomena that are best studied on the seafloor at margins.

    Rifting of continents creates new ocean basins. Oceans are formed, in part, by the outgassing of the planet at active plate margins. The geochemistry of fluids and mass balance of fluxes in submarine margin environments are least affected by the crust through which they pass and, therefore, most relevant to the origin of the oceans. These environments are unique to earth and processes unique to margin environments have been essential to life on Earth. How do substrate, depth distribution, and geochemistry of margins create variable life forms? Answers may be essential to understanding the origins of life, on Earth or elsewhere.

Global Biogeochemical Element Cycling. Plate margins cover about 30% of the oceans where most of the organic carbon and nutrient cycling occurs, hydrocarbon reservoirs are vast, and tectonically driven fluids are pervasive.

    Among the most important of these cyclic processes are gas hydrate systems. These dynamic systems, sensitive to subtle changes in pressure and temperature, represent an immense global carbon reservoir. They have the potential to drastically affect the global carbon budget and influence global geochemical change on a very large scale. Correlation between areas of gas hydrate and regions of massive slumps or slides suggests that these systems also are related to significant submarine hazard potential.

Biological Diversity and Productivity Benthic communities in margins are extremely heterogeneous both spatially and temporally. This heterogeneity is driven by variations in currents, nutrient input, oxygen availability, sediment and pore water constituents, topography, sediment dynamics, and substratum type. This complexity results in a wide variety of unanswered questions regarding biological processes at margin environments.

Paleoceanographic Conditions. Understanding of key taxa such as foraminifera, deep-sea corals, coccolithophores and fishes, as well as important processes such as bioturbation and microbial activity in present-day margin systems is necessary for reconstruction of paleoceanographic and climatic conditions. Certain margin environments such as nearshore anoxic basins and deep-water coral reefs are likely to contribute valuable historical information. The original invasion of the deep sea from shallow water faunas presumably took place by movement down continental slope. Therefore, investigations of the physiological and reproductive adaptations of slope species can provide insights into how these invasion and speciation processes have occurred and are presently occurring.

Anthropogenic Impacts. Over the coming decades, humans will affect margin environments more significantly than other oceanic environments. Margins will experience greater pressure from deep-sea fisheries as shallow stocks are depleted and the demand for seafood increases with increasing human population. How does fishing modify margin habitats, ecosystems and trophic linkages on the seabed and in the water column, and what fishing practices maximize sustainable harvest and conserve ecosystems? Margins, because of their proximity to human population centers, will be impacted with higher nutrient input from agricultural drainage, sewage, land use/abuse, deforestation, as well as various chemical pollutants. Organic loading can alter the structure of margin ecosystems through eutrophication and associated hypoxia while non-living resource exploitation has other effects.

Sediment Dynamics (erosion, transport, and deposition). Process-based models of marginal marine deposition and basin-filling remain poorly tested and constrained. The distribution of marine sediments is a primary control on the distribution of marine biological communities. Coarse-grained sediments host significant hydrocarbon accumulation and currently are the most important target reservoirs for the petroleum industry. High energy mass wasting events (debris flows, slumps, turbidity currents) pose considerable hazards to society, to marine engineering facilities, and pose a strategic challenge.

Influences of Deformation Processes. Deformation processes at margins control the largest scale topography, sediment transport and dynamics, and chemical fluxes, which in turn force links between biologic, chemical, and geologic processes, and hence the location and magnitude of resources and geologic hazards. Water/rock/organic-matter interactions during deformation change fluid compositions and, by altering rock porosity and permeability, create a feedback mechanism affecting fluid pathways and flow rates. These must be monitored in situ. These fluid flow and diagenetic processes represent important contributions to the global geochemical inventory. Many of these mechanisms, their rates, and the fluid pathways are still largely unknown.

Geologic Hazards. Subduction earthquakes are the largest energy releases on Earth. Because most of the Earth’s population lives within tens of kilometers of the coast understanding and monitoring forcing functions related to this seismicity is critical. We still do not understand the nature of strain accumulation related to great earthquakes.

    Mass wasting events accompany most large earthquakes in margin environments and cause far more damage close to the source region of earthquakes than does ground motion. Mass wasting can also be associated with sector collapse during volcanic eruptions and with large storms.

    The massive landslides in margin environments have generated devastating tsunamis. In order to understand and ultimately predict adverse affects accurately, what is needed are accurate models based on observations of phenomena both before and during events. Detailed bathymetry and imagery surveys and studies of physical responses to mass wasting must be carried out.

    Volcanic activity on convergent margins itself poses potential hazards for human populations and can have devastating effects on both subaerial and submarine ecosystems. Other hazards of importance on margins include hurricanes, storm surge, and flooding, yet we know very little of how storms and floods affect the biology and geology of margins.

Tectonic Forcing of Hydrologic Systems in Margin Settings. Episodic events, possibly associated with major earthquake rupture and accompanying ground motion, may dominate the flux of fluids at convergent margins. Variability of fluid fluxes within different portions of a given margin region may be related to both shallow and deep margin processes. These could include partitioning of fluid flux within the shallow outer forearc regions (prism or hard rock) and depths where fluids contribute to forearc mantle metamorphism or melt production the relative importance of transient vs. steady state hydrological processes. The presence of fluids in a margin setting does in itself alter the physical properties of the sediments and basement of which the margin is composed, therefore there is a potential feed-back loop between tectonic processes and hydrologic systems in these settings about which we know very little.

INVESTIGATIVE APPROACHES

    A variety of techniques and field/laboratory efforts are needed for studies of margins because the questions to be addressed are diverse and the areas encompass large and globally distributed regions at all latitudes. A global approach is required because the best examples of given margin processes do not all occur in a single region. Submersible vehicles capable of reaching a wide range of depths from shelf to trenches will be needed. Studies will require monitoring capabilities for both short- and long-term phenomena, in situ observation, sampling, and experiments for study of processes such as formation and/or dissociation of methane hydrates, fluid venting, and various responses of biological activity. ROVs and AUVs equipped with standard imaging packages and new coring devices can respond to individual events. Tethered, hard-wired observatories can provide time-series data on the magnitude and frequency of a variety of events.

    Additional vehicle assets, which complement submersible, ROV and AUV systems and a new suite of chemical, biological, and geotechnical sensors will be needed to examine and respond to episodic events. Some experiments and observations will require a seafloor observatory approach. Analogous to the Ocean Drilling Program, we must consider the possibility of multi-platform options. For example, there is a need for alternate-type vehicles such as bottom crawlers, with tools optimized for imaging benthic organisms and measuring such phenomena as respiration rates and microbial activities. Portable rock drills for use in both shallow and deep seafloor environments will also be needed to drill shallow holes into the upper ocean crust. Vehicles must be able to work in regions of strong currents, poor visibility, corrosive water, and near vertical slopes. There will be demand for heavy payloads to accommodate sampling in biogenic substrates such as reefs, crusts, and carbonate sands, and amongst biogenic structures (shells, tubes, coral debris). Finally, some critical questions can best be addressed with efficient response to unpredictable events.

    Improving our understanding of deformation at margins will require a better understanding of seafloor tectonics at a variety of spatial and temporal scales. Deep submergence assets are critical to address tectonics at smaller temporal and spatial scales, in much the same way as outcrop-scale geology and geophysics requires different tools than global studies.

    Some of the technologies are available and rely on deep submergence assets primarily for installation and maintenance of geodetic reference markers and specialized seismometric, geodetic and strain measurement systems, fluid flow experiments and direct sampling and observations. New technologies under development such as ship-deployable drilling and coring rigs, ROV mapping systems, and others not yet devised will be required to advance our knowledge of margin environments.

    All of the aspects of natural hazards that are outlined above are addressable with submersible technology, particularly geodetic and seismic monitoring, subduction zone physical properties, and tsunami warning systems. We will need medium to high-resolution surveys of targeted margins as the backbone of any comprehensive and multidisciplinary investigation. Submersible investigation of the 1998 New Guinea slide area proved the link between fluid venting and mass wasting. Monitoring microseismicity in areas prone to mass wasting events will facilitate forecasting. We also need detailed maps of venting regions in potential mass-wasting localities and monitoring of venting flux and composition. The study of hydrologic systems will require submergence assets to reveal tectonic processes occurring on smaller spatial scales than possible with surface assets and surface geophysics. The only way to study these sensitive systems in detail is by creating -in situ observatories and providing for submersible vehicles of various types to down-load data, collect samples, and service the observatories.
 

D. Polar Regions

    For many polar environments, little or no exploration has occurred using submersibles, let alone time-series measurements of key parameters over multiple spatial scales.

Polar Oceans. A great diversity of ocean environments exist in polar seas. They include ice covered seas over shallow continental shelf and slope environments, abyssal plains, mid-ocean ridge systems, seamount chains, and many others. For polar oceans and most ocean systems, the priorities for investigations generally progress from: (1) exploration and discovery, in which the basic elements of the system are identified, 2) characterization of the system, quantifying spatial and temporal variability of physical, chemical, and biological elements of the system over multiple scales, and 3) experimental and theoretical examination of processes expected to influence system dynamics. These studies must be followed by predictive modeling and synthesis of relevant elements of earlier studies, in order to characterize the dominant sources and patterns of variation in the system.

Global Climate Change. Polar amplification of climate warming (especially in the Arctic), coupled with accelerated climate warming expected in the next century, underscores the need for climate-related research in polar oceans. For example, there is temporal correlation between a fundamental change in the atmospheric circulation of the Northern Hemisphere and (1) the temperature increase of the Arctic Ocean Atlantic water, (2) the increase in the surface air temperature over the Russian Arctic, (3) the Arctic Ocean circulation changes, and (4) the freshening of the upper Beaufort Sea. These observations suggest the recent change in the Arctic is at least a decadal scale phenomenon and has broad implications for changes at lower latitudes. What is needed are long time-series measurements of physical variables, process studies, and modeling to track and understand the changes. We need to understand how changes in sea ice thickness and extent occur, and the consequences of such changes to upper-ocean hydrographic structure (density structure, formation, position, and intensity of oceanic frontal zones and other hydrographic interfaces), and how they affect climate change.

    Research priorities include studies of shelf and basin patterns (physical and biological structure) and processes (biogeochemical cycling, physical oceanography, population dynamics), and interactions between the Arctic shelf and basin environments (e.g. carbon export from shelf to basin).

Arctic and Antarctic Ecosystems. Biological diversity can be considered at three levels, genetic, species and ecosystem diversity. The first involves the variety of genetic information contained in individual plants, animals and micro-organisms that inhabit the system. It occurs within and between populations of organisms that comprise individual species as well as among species. Understanding the natural variability of marine ecosystems is the goal. However, there are some fundamental questions for which we do not yet have answers. These must form the basis of our approach to understanding ecosystems in polar regions.

Glaciation. Glaciological research is concerned with the study of the history and dynamics of all naturally occurring forms of snow and ice, including seasonal snow, glaciers, and the ice sheets. Studies of interest to submergence science communities include history of glaciation in the polar regions, ice dynamics, and remote sensing of ice sheets.

INVESTIGATIVE APPROACHES

    Certain types of polar research will require new vehicle designs. For example, sampling of under-ice habitats is presently limited or impossible using existing submersible vehicles. The study of ecosystems, such as the mechanisms necessary for maintenance of cell function in fishes and their feeding behavior, require long-term observations. Such studies are needed to improve understanding of man-made or natural changes. Advances in instrumentation, including remote sensing or telemetering of ice type, thickness, motion, and growth, should enable large scale dynamics of sea ice to be monitored over long periods. Recent studies indicate that melting of Antarctic ice shelves progresses largely by melting from below, rather than ablation or melting on the surface. Monitoring such processes is critical to understanding the controls over this process. Increased access to sub-shelf cavities using submergence technology for studies of hydrography and glaciology is a desirable. Studies of the polar oceans will by necessity require a wide range of vehicles or systems. OSVs, ROVs, and especially AUVs. AUVs may be required for synoptic characterization of the Arctic Basin (requiring long range and long duration AUVs or other unattended vehicles (e.g. rovers). Long-term installation of sea floor observatories, either cabled to shore stations, or moored, equipped with sensor packages for water column and sea floor sampling will also be required. Submersibles will also be needed to support geophysical, geological, chemical, biological and other studies of polar rift zones. In addition, capabilities for drilling (core collection), high resolution mapping, and imaging, and sample collection devices will be needed. A key requirement for polar science where access is often logistically difficult, will be the deployment of fleets of AUVs for time-series measurements of various types and establishment of ocean floor observatories and programmable monitoring arrays served by AUVs.
 

E. Coastal Environment

    Coastal zones present challenges to exploration that are different from those of the open ocean and the deep sea. Physical conditions are often harsh, making it difficult to mount ship-based expeditions, yet most of the US population lives within 50 miles of the coast. Thus, there is high interest in coastal oceanographic processes, especially when these have an impact on human activities or welfare.

Coastal Impacts. Events such as harmful algal blooms, storms, introduction of exotic species, upwelling, bottom-water anoxia, oil spills, and other pollutant plumes can result in long-term impacts on coastal processes. The effects of various pollution phenomena have attracted a great deal of attention, but the details of the effects of these on the complex physical, chemical and biological systems in coastal environments are still poorly known.

Physical Oceanographic Interfaces. Fronts and thin layers are common features of the coastal ocean. For instance patterns of turbulence on the shelf during up-welling and down-welling events are influenced by fronts and jets, and the levels of turbulence can reach sufficient intensity to influence the mesoscale circulation. The effects of the dynamics of mid-water circulation patterns on the water sediment interface are poorly known. Interfaces are intrinsically ephemeral and sensitive to physical, chemical, and biological variations on several time scales.

Seafloor Topography and Sediment Properties. Physical forcing from waves, tides, and storms, coupled with the activity of benthic animals, leads to a dynamic seafloor over most of the continental shelf. Seafloor topography (e.g., sand waves, ripples) and sediment geotechnical properties (e.g., shear strength, porosity) are affected. Along-shore topographic variations dictate the relative importance of two-dimensional versus three-dimensional cross-shelf transport processes with respect to wind-driven dynamics. Coastal morphology is affected by these functions and thus societal concerns are important aspects of the study of physical forcing functions in coastal regions. These effects impact biogeochemical processes. For example, most of the organic matter produced in shelf waters appears to be recycled on the shelf, not exported to the slope or deeper water. A significant portion of this organic matter appears to reach the bottom, where it is rapidly removed as water flows through the permeable, sandy sediments found on much of the shelf. The interactions of waves and currents with an uneven, permeable seafloor are responsible for driving this "subtidal pump."

    Submerged reefs record the history of eustatic sea level change and the regional dynamics of tectonic uplift or subsidence. Correlations among globally distributed reef deposits will enhance our understanding of global climatic variability. The variability of coastal morphology both near-shore and on the shelf as a function of various forcing phenomena has important implications for military applications (such as object detection).

Lake Phenomena. Many of the processes operating in the coastal ocean are also important in lakes. One of the most critical aspects of lake studies is the record of climatic change that is preserved in remote locations in lakes throughout the world, including polar regions. Studies of individual lakes and global comparisons of the sediment records preserved in them are both essential components of the history of climate change.

Essential Habitat. Anthropogenic perturbations and natural variation can adversely affect habitats of ecologically, commercially, and recreationally important species. Midwater and benthic fish communities, shellfish, and coral reefs are examples. The diversity of habitats is poorly known even in the shelf and coastal environments. In the 50-300 m depth range globally there are many communities that are poorly understood, particularly those other than sediment hosted communities. These communities have complex interdependencies on the geological framework for ecological niches. Effects of physical and chemical forcing functions on these communities are virtually unknown. These communities are sensitive to disturbance and a silent approach is needed in order to observe normal community behaviors (sole diver with re-breather). A more effective and less hazardous approach would be to employ ROVs or AUVs. We need to understand better the overall effects of anthropogenic perturbations to the natural system. What is required is a quantitative comparison among the responses of various ecosystems to a given perturbation. This necessitates an approach that includes both short-term and long-term monitoring

INVESTIGATIVE APPROACHES

    The need to survey and map the extent of various coastal events would be best met by rapid-response submersible vehicles, such as AUVs. Because these events are often widespread and evolve rapidly, synoptic sampling is required to prevent space/time confounding. Thus, numerous, inexpensive vehicles that can be deployed as a fleet to track these features would be ideal. Sensors capable of measuring basic chemical and physical properties of the water are widely available and should be standard equipment. Additional sensors, which could be used for identification of specific compounds in the water and even specific organisms (e.g., toxic dinoflagellates), should be employed as well. It is likely that such sensors have already been developed for other applications (for example, molecular and genetic probes), and could be used either as-is or adapted for oceanographic use. Navigation networks capable of tracking and controlling such fleets of submersible vehicles will need to be developed.

    Interface areas of physical, biological, and chemical discontinuities can be widespread and rapidly changing. Ship-based sampling is usually impractical. Submersible vehicles, either remotely controlled or autonomous and capable of following gradients in water properties, probably represent the best method of studying interfaces.

    The problems of addressing physical forcing functions in coastal environments could be addressed with submersibles equipped with sensors for measuring porewater chemistry and sediment physical and acoustic properties. These could be used to survey spatial patterns of seafloor topography and sediment properties, their linkage with water column processes, and how these interactions change over time. The availability of easily mobilized and demobilized AUVs would pay large dividends in lacustrine research. AUVs, ROVs, and submersibles, equipped with high resolution visual systems (e.g., laser line scanners) and more sophisticated, articulate samplers are needed to document spatial and temporal changes in essential habitat and understand the factors driving such changes. In order to obtain samples for studies of sediment properties it will be essential obtain drill samples. These samples must come from below the zone of bioturbation and below wave base. The optimum types of drills envisioned are relatively inexpensive portable drill systems that can be used with an ROV (for use in drilling into submerged coral reefs, for example). Also needed is a relatively inexpensive coring system that is tethered, but mobile, and equipped with a real-time video for obtaining precisely located cores on the order of 3 to 20 m deep in the shallow water environment. The study of the geological framework for ecologies of various types of sensitive biological communities would require as unobtrusive an approach as possible. Such work is more suitable for ROVs or possibly AUVs. Both short and long-term monitoring of such communities might best benefit from arrays of fairly simple sensors serviced by AUVs.
 
 

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III. Technical Sessions

This portion of the workshop defines strategies to ensure that the facilities and technologies
needed to address the scientific themes defined in the Science Sessions are available. Critical
issues, needs, and problems, both technical and infrastructural, were defined. The objective is to
help to direct future upgrades of science sensors, sampling techniques, and imaging capabilities of
vehicle systems funded by the federal agencies.
 

A. Event Response

Occasional or periodic perturbations of ocean systems may have a profound impact on both local and distant integrated physical, geological, geochemical, and biological processes. The time scales from initiation to system recovery vary considerably. Most are unpredictable. Studies of such events pose tremendous scientific opportunities and major technical and logistical challenges. These events evolve rapidly, requiring swift deployment of required observational and sampling systems. Effective event responses are constrained by the availability of personnel and equipment at extremely short notice, funding availability, and weather constraints on over-the-side operations. Because most event response studies can best, or only, be accomplished using a submergence vehicle or tool, the availability and capabilities of submergence assets and their support systems are particularly critical.

The types of phenomena that cause sudden perturbations are diverse, and affect coastal, deep ocean, and lacustrine processes. They can include erosional events, dewatering or hydrocarbon release, volcanic or hypabyssal magmatic events, seasonal biological phenomena, storms, tsunami generation, anthropogenic events, etc. The various types of events commonly require both water column and seafloor response components. The potential for very rapid deployment, transportability, and for truly autonomous operation when weather conditions may preclude over-the-side operations makes AUVs the optimal tool for response efforts. Two separate, task-dedicated vehicles are highly recommended for responses to compound events.

*Water Column: A water column response might generally require an AUV capable of performing 2 or 3-dimensional surveys using a CTD and variable arrays of optical, chemical and bio-sensors. Survey dimensions could require tens of square kilometers of spatial coverage and depth ranges of over 1000 m. "Smart" AUVs would be required to locate and survey "event," plumes, etc., by virtue of optical (e.g., threshold optical backscatter) or chemical tracers. AUVs equipped with high turbidity sensors would be required for many coastal events (e.g., storm sediment transport, mass-wasting events). Seeding of event plumes or other subject water mass (e.g., plankton bloom, oil spill) with Lagrangian drifters for tracking and relocation would extend the rapid response observations to time-series studies. The scientific community interested in event response strongly encourages the submergence engineering community to examine the practicality of designing a hybrid vehicle (i.e., 3-D Lagrangian float and AUV) for some of these water column operations.

*Seafloor: A robust AUV would be required for seafloor mapping and sampling. AUVs equipped with an array of mapping sensors can be used during an event-response expedition to efficiently detect and map the extent of anomalous regions on the seafloor. Mapping the environment also could be used as a navigational aide in comparison with previous maps where possible. Responses to dynamic sediment processes also require the capability to measure concentration, turbidity, and velocity through active sediment-gravity flows over the duration of the event using laser, acoustic backscatter, and sub-bottom profiler systems. This technology could be used to map concentration, velocity, and turbidity variations along AUV transects during a storm event on the shelf. High-resolution imaging is a high priority for documenting physical (e.g., vent sources, boulder size) and biological (e.g., vent fauna, microbial mats and "blooms") phenomena.

Optimally, the seafloor response AUV would be capable of limited fluid sampling for chemical and microbiological studies. Fluid sampling should include the use of physical, chemical and bio- (DNA-chip) sensors, and possibly the physical collection of small fluid volumes and their preliminary preservation (e.g., poison, filtration). Shallow sediment and sand cores (up to 1-2 m) collected shortly after a sedimentation event (hours to days) can provide important information on sediment thickness, texture, and structuring. Rock coring capability is also highly desired for both the core sample and the consequent access provided to subsurface fluids and biosphere.

Manipulative capability would allow the relocation or recovery of pre-event staged equipment. This could be manifested in little more than a "releasable hook". A suspected sedimentologically active area site (e.g., near the head of an active submarine canyon or within an active channel) could be ‘seeded’ prior to an event with small, negatively-buoyant transponder packages (so-called "smart rocks"), that behave as clasts in a bottom current. If relocated and recovered shortly after a sedimentation event they would provide unique data on the distances of transport and, therefore, estimates of boundary shear stress and velocity.
 

Critical Issues Related to Event Response. These include appropriate detection capability, adequate submergence vehicle and surface ship assets, and a stable long-term infrastructure support system. Submergence vehicle operations depend in turn on precise navigation, science task-specific capabilities, and pre-event staging.

* Event detection capabilities: Event response obviously depends on reliable event detection. Detection systems of coastal seismic or storm-related events are based on well-established and stable facilities (shore-based seismographic networks, satellites). The MOR event detection and response community has been able to productively exploit the Northeast Pacific SOSUS system since 1993. US Navy commitment to maintenance of SOSUS is declining and additional funding will be required from non-military sources. There are other exciting new possibilities on the horizon, including remote telemetered hydrophone mooring systems (after PMEL’s Haruphones). Additionally, if and when a cabled system such as NEPTUNE comes on line, it is highly likely that it will be well equipped with its own hydrophone array, removing dependency on the aging SOSUS system.

* Availability of vehicles: The current availability of submergence vehicles is inadequate for planning and staging effective rapid response efforts. The time-sensitive nature of event response precludes reliance on assets that may need to be packaged up and shipped to the staging area from some remote location. For example, on the west coast the only US National Submergence Facility vehicle that it is currently possible to pre-stage in geographic proximity to a potential northeast Pacific event is a camera sled. It provides valuable seafloor imaging, but of only limited spatial coverage, using limited and precious response time and it is very weather constrained.

The Event Response Session participants strongly urge the funding agencies and submergence technical community to provide additional submergence vehicles. Event response oriented recommendations emphasize AUVs and modified ROVs. These recommendations are based in part on a vision of optimized event response efforts and in part on the realization that certain assets (i.e., full service ROV or occupied submersibles) are unlikely to be available within the short time frame of effective response efforts. The group proposed several scenarios that include the following:

- Dedicated event response AUVs prepositioned in close geographical proximity to a region of expected event site(s). Ideally, an AUV or group of AUVs could be pre-deployed in situ as part of a cable (e.g., HUGO, NEPTUNE) or mooring system. AUVs could be docked in sleep-mode until activated for response or could also be used for observatory-related or other interim work. Alternatively, the vehicle could be staged on shore, ready for rapid transportation to a response-ship of opportunity. Because certain coastal storm-related events are inherently more (quasi-) predictable than other types of events, there may be a warning of up to several days for final staging of response efforts for some coastal and lake events.

- AUVs as standard UNOLS ship equipment: The cross-disciplinary and global usefulness of AUVs as an oceanographic and geophysical support tool should encourage the UNOLS and funding community to elevate its status from that of novelty to accepted workhorse. This working group urges consideration of the proposal to equip every or many UNOLS ships with a standardized AUV. A mass order of similar AUVs would drastically drop the per-unit production costs; the costs of even a well-instrumented (e.g., geophysical and imaging mapping tools and water column sensors) AUV would likely be on par with that of a CTD/winch/wire system.

- Response Support Ship: Regardless of the nature of AUV asset deployments, a surface response ship will likely be required for all thorough response efforts. In all cases except that of a sophisticated cable system, the ship will be necessary for data recovery and for recovery and servicing of the AUV. Even a moored docking system would likely require servicing in terms of power. In all cases any actual water, fluid, biological or geological samples would need to be recovered for analyses. Consequently, the issues of ship availability and priority rescheduling at short-notice need to be explored for possible solutions. One possibility might involve an attempt at scheduling rotating "open" spots in ship schedules for ships within specific regions so as to maximize the time for which at least one UNOLS ship might be available for response efforts. If UNOLS ships were generally equipped with AUVs, a ship in the vicinity of an event could steam to site and, at minimum, drop an AUV and return to their original project work. Mechanisms for rapid funding of pre-approved commercial vessels need to be designed and implemented.


* Optimum response vehicles: As noted above, the sampling requirements and logistical realities of most event response efforts suggest that the primary submergence assets for event response should be the AUVs. However, AUV design needs to be optimized for the specific operations required. As described in earlier sections, the event response group strongly advocates development and pre-event staging of two AUVs with different capabilities. The requirements of the optimized ‘seafloor’ AUV are more demanding and require an overall more robust vehicle than the ‘water column’ AUV in terms of mass, power, instrumentation, and manipulative capabilities. The event response group also recognizes the potential counter-productivity of over building an AUV. The group discussed some alternative vehicles.

- Portable/limited task ROV or telemetry capable AUV: Such a minimal ROV could be maintained on "rapid access" status. Considering the depths at which we expect many of the events to occur, the winch and wire handling equipment that full ROVs require is heavy and bulky, requiring a large ship. It is unlikely that a full-scale deep ROV and support ship would be available within an extremely short response period.

One compromise is to operate an AUV as a "tetherless ROV" with an acoustic link. This would make a much smaller and portable kit that could be operated from a wider range of ships. In the vertical acoustic path, one video frame in 3 to 30 seconds (depending on quality) has been realized. This would require the hybrid AUV/ROV to be operated in a "chess game" mode, where as each image is received, the next target is selected. The vehicle would then make its surface-directed move (e.g., collect vent fluids) and then hover while reporting to the surface and receiving its next instruction.

Such an AUV would be somewhat power demanding, as it needs to compress and transmit a video image and also operate a doppler bottom lock log to hold position while waiting for the next word from on high. This would limit it to perhaps eight hours on the bottom, during which the ship could perform other over the side operations. Such an AUV could of course also be used for unsupervised surveys such as area mapping or plume tracking. The vehicle would return samples to the ship and receive a battery recharge and other service.

- Hybrid AUV/Lagrangian float: Tracking and relocation of event related water masses is an invaluable component of responses to many different types of events including magmatic event associated plumes and seasonal plankton blooms. It is the primary means by which subsurface plumes can be monitored and sampled over time without a constant ship presence. Simple Lagrangian drifter floats have been shown to track such water masses for months. However, such floats record little other than temperature and position, and nothing about the 2- or 3-D structure of the water mass. Navigation requires sound sources to be in place. Alternatively, some floats (e.g., ALACE) are capable of operating without a local navigation support system by recycling to the surface to both receive navigational information and download data via satellite. However, the combined total vertical transit time from deep plumes to the surface plus surface data transfer time would likely cause a disconnect from the original target water mass. Some kind of "smart" float, or hybrid between a Lagrangian float and AUV, could both track the target water mass using either in-place navigational network or a self-contained system (coupled INS/DVL/GPS navigation systems) and periodically make at least a limited 3-D sensor survey of the water mass. Not only would this provide time series information of the structure of the water mass, but could cue the hybrid float/AUV as to its approximate center, thus helping to insure that the vehicle remains with the target.

- Shallow water, high-energy vehicle: For the coastal zone, an AUV is needed that has the capability of operating in shallow water, high energy (currents to >1m/sec) environments. The vehicle would require high power and be survey capable with a versatile payload arrangement

* Navigation problems: Navigation, already a major element of the cost of operating underwater vehicles, is particularly demanding for rapid event response. The difficulty stems from the requirement that platforms operate off of ships of opportunity, with a minimum of setup time, and probably a minimal crew. Under less constrained circumstances, key navigation elements, such as ultra-short baseline acoustic tracking systems, are either provided from an already well-equipped ship, or are carefully installed on a ship of opportunity. Note that not all ships are friendly platforms for acoustic systems, so the need to operate acoustic tracking, navigation, and acoustic systems may preclude use of some ships, and implies some level of pre-screening of possible vessels. If long-baseline navigation is used, then the transponders commonly used by the scientific community today must be deployed and calibrated at significant cost of ship time. For a rapid deployment effort, these impose delays on the order of a day. This loss of time might be compounded if subsequent measurements determine that the array is deployed in the wrong location, and must be redeployed.

Clearly the most attractive navigation capability for rapid event would provide the platform with a self-contained navigation system. The only systems that currently satisfy this requirement are coupled INS/DVL/GPS navigation systems. These are used in military underwater vehicles today, and could be obtained by the scientific community. While expensive, such an approach may be the most cost-effective for this application. Ongoing development will likely bring costs down and performances up in the future. The development of sophisticated cable network systems as proposed for NEPTUNE would likely provide a stable, widespread, well-maintained transponder net for acoustic navigation in select areas.


Technological Needs for Event Response: A detailed list of the identified technological needs is given in Appendix 1 and shown in Table 1.

B. Time-series Short 

Events in the oceans take place on a variety of time scales. The short time-series events
are defined here as those events or processes that take place over periods of less than
one year. The investigation of many of these phenomena requires access to shallow
water submergence vehicles and tools. At the short end these merge with event
response. They can also span periods of weeks to months and can cover a range of
annual phenomena

Critical Issues Related to Short Time-series Studies. Comprehensive event response
depends on the satisfactory solution of a number of critical problems. These include
appropriate detection capability, adequate submergence vehicle and surface ship assets,
and a stable long-term infrastructure support system. Submergence vehicle operations
depend in turn on precise navigation, science task-specific capabilities, and pre-event
staging.

* Gaining access to vehicles and tools is a critical problem for investigation of these
phenomena. Many take place in shelf environments and access to vehicles to use in
shallow-water is difficult to obtain. Access to deep seafloor, depths in excess of 6500 m
(submersible or ROV) is needed by the deep-sea community. Currently there is none
available except by cooperation with foreign investigators.

* Standardization of basic operating tools among submersibles. This is a general
recommendation, but is particularly relevant if there is a high demand for study of
short-term phenomena in many localities simultaneously.

* Development of chemical and other sensors is needed to affect a variety of in situ
biological and geochemical measurements. Examples of these include: Redox-sensitive
chemical species, particularly those influenced by hydrothermal reactions: pH, O2, H2,
Mn2+, Fe2+; Chemosynthetic substrates and products: H2S, CH4, H2, Mn2+, Fe2+, CO2,
NH4, NO3-/NO2-, N2O. Also sensors for measurement of metabolism, e.g., respiration
and excretion, salinity (not CTD) are needed. There are constraints associated with such
sensors. Development of sensors may require time periods much longer than the typical
2-3 year single PI NSF grants. They must be designed so as to operate on a variety of
submersible platforms. A common pool of general-purpose sensors (e.g., temperature,
conductivity, pressure, transmissometer, oxygen, pH, H2S) is also required. There will
be a need to support operation, calibration and maintenance of the sensors in the field.

 * Flow Sensors and Pore-water Flow Measurement: Robust and portable devices to
measure water velocities over a large range of values (< 1 mm/min to 10s of cm/sec) on
the seafloor are needed. These sensors must be capable of measuring flow rates of
particle-rich, high temperature vent fluids, and should have low power requirements and
the ability to send processed data in real time to the pilot and observers. Submersible
acoustic Doppler velocimeters that meet most of these requirements are currently
available for depths <2000m, but are not available for full ocean depths. Very low
velocity flowmeters are required in order to determine pore-water flow rate variability
over short (minute – hour) time scales. Many areas of the seafloor are sites of
pore-water advection from the sediment to the overlying water, and these fluxes may be
significant contributors to local and/or regional biogeochemical cycles. Several devices
are available for collecting these fluids and measuring their flow rate integrated over
extended periods of time.

* Observatories: For short-term studies, "temporary" observatories offer advantages
over cabled observatories. Because of their stand-alone status, such observatories will
require adaptive sampling algorithms that can alter sampling frequencies of connected
instruments and sensors in response to events of interest. In coastal waters we can
predict events such as hurricanes and blooms.

* Optics: 

- Video needs for all vehicles include:

·        High definition digital video cameras with telemetry systems and high quality lenses that are good for media purposes.

·        Support equipment for high definition cameras/ IE recorders/ monitors, including conversion equipment from high definition to more user-friendly format.

·        Simple camera controllers for operation by scientific observers.

·        Smooth, variable speed pan & tilt camera with simple controller

- Electronic/digital still cameras with large storage capacity

* Lighting: Red light operation for biological purposes will be required. HMI (400 watt/
1200 watt) will be needed.

* Manipulators: Multiple-jaw designs will be required for various sampling tasks.
Resolution to mm scale with very smooth articulation is needed. Programmable
manipulators in XYZ for accurate placement of devices and for repetitive operations
need to be developed. Forced feedback is needed for care in sampling.
Computer-controlled sediment profilers for microelectrodes are needed.

* Sampling Devices: Gas-type manifold for chemical sampling in the water column.
Improved corers for coarse and hard sediments are needed. Very soft sediments can be
sampled with punch cores and box cores from ROV’s and occupied submersibles.
However, sandy sediments, sediments with large particle inclusions and sediments with
tubes or other subsurface structures generally cannot be sampled by traditional coring
methods. This is a major limiting factor in biological sampling over much of the sea floor,
particularly in shallower coastal and margin habitats. New technologies are needed for
sampling such sediments. Vibrating corers may be a solution for sandy sediments.

* Drilling technology: We need to resolve deficiencies in existing technology regarding
drilling on the seafloor.

* Appropriate sampling of biological specimens: The biological community, particularly,
needs to be able to amass collections that are made gently, maintained in discrete and
separate containers on the way to the surface, and arrive at the surface at ambient
temperatures and pressures. Where sophisticated suction samplers have been
developed, they have proven to be almost universally better for gentle collection of
biological samples than traditional manipulator arms. The JSL technology in which
suction hoses lead to large, lazy-susan, indexed collection containers should be
examined for possible application to submergence vehicles.

Technological Needs for Short Time-Series Science: A detailed list of the identified
technological needs is given in Appendix 1 and shown in Table 1.

C. Time-series Long

Processes that take place over extended time spans may be at equilibrium or may be continually changing in response to fluctuations in the environment on shorter time scales. Long time-series measurements require decadal and longer commitments of investigators, assets and funding. Two types of long time-series studies must be considered, periodic and continuous. Periodic measurements involve repeat measurements of slowly varying parameters on a regular basis. These may include geodetic studies, water column measurement, and growth rate of ecosystems (though optimally this would also be continuously monitored). Periodic observations usually have low data rates, do not require continuous presence, require less infrastructure, and are less complex than continuous measurements. Continuous measurements often require installation of monitoring devices on the ocean floor that necessitate considerable dexterity with an occupied vehicle and interdisciplinary experiments that commonly share extensive infrastructure. These might include seismic monitoring, studies of flux rates of pore fluids in hydrologically active areas, monitoring the life cycle of a particular ecosystem. In most cases, where continuous studies are envisioned, the time series should be monitored indefinitely, meaning decades to potentially hundreds of years for detailed understanding of the phenomena,

Critical Issues Related to Long Time-series Studies.

* Manipulators and tools: Since manipulator and tool technology are not standardized, hardware should be designed for servicing by "generic" manipulators and vehicles. Future design of manipulators and tool sets would benefit from standardization of interfaces for ease of use.

* Connectors: Similarly, standardization of electrical and optical connectors and power interfaces for ease in moving scientific hardware from one system to another would be cost effective.

* Benchmarks: Long time series often require exact positioning on the ocean floor, possibly obtained by occupation of or reference to benchmarks. Benchmark technology needs to be improved to provide mm accuracy for extended periods. Precise location of transponders will require short tethers or mounting on tripods and possibly battery packs that can be replaced on the ocean floor. Transponders can be connected to cabled observatories for power and continuous processing of data on shore.

* Observatories: Observatories are a fundamental requirement of long time-series research. Observatory research has a number of technologic requirements.

- Required assets: Installation of multi-use observatories for measurement of continuous time series will require substantial capabilities for installation. Cabled observatories for example, will require the use of cable laying ships, multiple ships for laying multi-leg moorings, heavy-lift ROVs for installation of junction boxes and other equipment, and substantial ROV time for ongoing installation, maintenance, and removal of experiments.

- Need for new assets: Increasing demand for long-term experiments will require the operation of a new ROV system comparable to the JASON/MEDEA or ROPOS systems within the next few years. Important characteristics of this system include heavy lift capability, long bottom time, and dexterity in manipulation.

- Observatory maintenance: Submersible assets will be required for maintenance of observatories, addition and removal of sensors, and extensions of the infrastructure. Periodic visits will be required for maintenance of transponder networks, replacing expendables, and for calibration of some sensor systems. The high cost of such visits requires that substantial front-end effort and funds be made available to make the systems as robust and reliable and as possible. Use of redundant systems, modular components that can be easily removed and replaced, and use of generic submersible interfaces that allow use of a number of assets for the same task.

- Flexibility: The high cost of such systems can be mitigated by making them very flexible for use by many different instrument systems. Flexibility includes availability of a variety of data rates, power, and control systems such that both low demand systems, such as thermister arrays, and high demand systems, such as video systems, could be accommodated. The design of these systems should assume high power consumption, large data rates, and requirements for command capability. Any functionality offered is likely to be used.

- AUVs, etc.: Some systems will require docked AUVs for collection of data beyond the spatial extent of the observatory and for rapid response to transient events. Similarly, some sites will require fixed manipulators that can sample, image, and take measurements of a feature such as an active vent for an indefinite period. Bottom rovers could perform similar functions, much like the mars Pathfinder rover. Such active research components will be particularly interesting and appealing for outreach programs. With sufficient electrical power, it is also be practical to provide a freezer to store biological samples until they can be collected.

- Shared infrastructure: At sites where water column measurement systems (GOOS and others) are planned, the feasibility of including bottom sensor systems on such buoyed arrays should be pursued. Similarly, the inclusion of vertical arrays and other water column measurement systems would not substantially increase the infrastructure effort of a bottom observatory. At the very least, placing water column and bottom observatories at nearby locations whenever practical would considerably reduce the ship-time component of maintenance costs. We encourage interaction between the concerned communities to evaluate the possibilities of shared sites and infrastructure. It may be desirable to have recommended minimum suites of sensors for observatories to maximize cost effectiveness.

* Networking among technical groups: Continuous long time-series experiments will require systems that will be designed to last for decades and longer. Thus, dissemination of information concerning new developments with regard to batteries, corrosion, connectors, reliability and other engineering issues would benefit greatly from regular meetings between technical groups and the establishment of WEB sites.

Technological Needs for Long Time-Series Science: A detailed list of the identified
technological needs is given in Appendix 1 and shown in Table 1.

D. Global 

Global submergence science research encompasses three possible approaches. (1)
Some global research requires simultaneous observations at many sites distributed
worldwide. For example, the ocean seismic network (with as many as 20 permanent
broadband seismometer installations globally distributed in fairly remote areas) will
require submergence assets for installation and/or servicing and experiments to test
linkages among oceanographic processes spanning large sections of the oceans will
have to be done simultaneously. (2) Some global research requires detailed surveys,
observations, sampling and experimentation at various sites distributed around the
globe, but not done contemporaneously. For example, global mapping of distributions of
hydrothermal activity and vent fauna will need to be done at several sites around the
globe and studies of various margin processes will need to be performed where they are
best exemplified. (3) Models developed by detailed studies at "representative" sites
need to be tested in other (often remote) locations. For example, the connection between
tsunamigenic events and submarine slumping must be explored in regions with a variety
of tectonic, structural, sedimentological and hydrological characteristics.

Critical Issues Related to Global Studies. 

* Availability of current submergence assets. For global studies, the situation is made
especially acute by the strong draw of current assets to support long-term time-series
observations at representative sites on the Mid-Atlantic Ridge, East Pacific Rise, and
Juan de Fuca Ridge. While this emphasis has been solidly justified by strong
peer-reviewed science, in the present system it has curtailed access to submergence
assets for science at more globally-distributed sites.

* Diversity of Assets: If visions for seafloor observatory science by planning efforts
such as DEOS reach full fruition, demands on submergence assets will be even stronger
for regular servicing at a few select sites.

In the context of the Global group mandate, it was clear that almost the entire range of
conceivable submergence functions would be required, in various combinations
appropriate to the particular science requirements and the environmental conditions
within which the research would be conducted. Matching vehicle types and instrument
suites to the particular range of tasks at hand will be essential to the science- and
cost-effective overall use of submergence assets present and future.

It is clear that scientific needs in the global context will call for the use of submergence
vehicles from all three of the basic types: occupied submersibles, ROVs, and AUVs.
These needs encompass vehicles that function effectively in the water column as well as
those designed to operate on the seafloor. The latter case includes benthic crawlers as
well as AUVs that fly above the seafloor. In each case, there are a variety of issues that
must be considered. Operational depth requirements range to depths as great as 6000m
or more, yet a significant need exists for vehicles that operate efficiently in the upper
2000 m. Economical use of assets suggests that vehicles designed for maximum depth
are not necessarily the most appropriate platforms for work at shallower depths, and
that alternative vehicles should be developed and/or made available.

Deployment characteristics vary with the type of platform and the mission at hand.
Endurance needs range from hours to a day for occupied submersibles, from hours to
days for ROVs, and from days to months for AUVs. Areas and volumes surveyed vary
accordingly on scales from square meters to square kilometers and cubic meters to
cubic kilometers, respectively. Linear surveys range from meters to kilometers for all
vehicles and up to basin-scale for specialized AUVs.

* Sensors and Sampling: In general, global science applications of submersible
technology have similar requirements for sensors and sampling capabilities, as do
applications at other scales. There may, however, be a difference between the needs of
exploratory work for a broad range of sensors to detect previously unknown physical,
chemical, and biological signals, and the needs of fixed observations for highly specific
sensors tuned and calibrated to specific, known processes.

Physical properties sensors may include pressure, temperature, magnetization, gravity,
and in some cases, light distribution for down-welling and bioluminescent light.
Multi-spectral sensors might eventually extend to low-frequency radiation at vent sites.
Current and flow sensors are needed mainly for vent-related work. Chemical sensors
may be used both to locate and identify geochemical or biological features at longer
ranges, and then to quantify and characterize them at short range. Highly sensitive and
specific chemical sensors recognizing particular chemicals and proteins, or nucleotides
may be realistic in the near future. Acoustical and optical sensors provide the
morphologic constraints on geologic features and organisms at varying ranges and
resolutions both on the bottom and in the water column. High-definition video and
photography extends the resolution progressively down to the near-microscopic.
Multi-spectral imaging techniques may be valuable in some situations, and in-situ X-ray
imaging can reveal internal structure of biological or geological features.

Submersible platforms need to be able to accommodate a variety of sampling devices for
water, geological materials, sediment cores, and biological material. In any case, it is
important to have the maximum capacity for multiple samples, especially for vehicles
like ROVs and AUVs with long deployment times and/or distances. It is essential to
avoid cross-contamination of samples, to index each with respect to collection and
environmental data, and to preserve the chemical, geological, or biological integrity as
much as possible. This may mean retaining ambient temperatures and pressures,
preventing degassing, or providing in-situ fixation of some biological specimens.

Sampling modes for benthic environments include selection and manipulation of
individual objects, coring and drilling for subsurface samples, and collection of water
samples from specific locations. Deeper coring capabilities and better ways to maintain
the physical and biological structure of cores are desirable. Water-column biological
sampling requires suction collectors with multiple chambers, and enclosure-type samples
("detritus samplers") for especially fragile organisms and structures. Small-volume
water samplers that can be positioned precisely are valuable for thin-layer features,
detrital aggregates, etc.

These sampling and sensor issues require improved dexterity of manipulators,
advancements in communication and data transfer mechanisms, and power, payload,
propulsion, and structural materials of platforms.

* Navigation: Navigation systems are an essential element in carrying out all three
essential categories of global submersible operations. Work in support of systems such
as the Ocean Seismic Network can be supported with conventional long-baseline
transponder systems. These can be used in other configurations scaled up or down to
suit the area to be covered and the resolution required. In the global survey mode,
short-baseline navigation of vehicles relative to their GPS-positioned tending ship may
in some cases be an operationally preferable option. A special problem arises if assets
are air-deployed into areas without extant transponder nets. In this case it may be
necessary to provide means for generating tracks by use of dead reckoning (compass
plus inertial and/or seafloor doppler) from a GPS-determined initial water-entry datum.

* Operating in Extreme Environments: Specialization may be required to cope with
unusual conditions such as strong currents (e.g., Gulf Stream, Kuroshio), highly sulfidic
environments (e.g., Black sea, hydrothermal plumes), high temperatures (e.g.,
hydrothermal systems, volcanic environments), or high salinity (e.g., Red Sea brines).

Weather extremes pose problems relating to vehicle launch and recovery. Vehicle
characteristics themselves can help mitigate these difficulties, but primarily they
concern support ships and handling equipment. These could dictate use of interior wells
or deep draft stable platforms (e.g., swath ships) to carry out winter operations at high
latitudes.

Pre-deployed AUVs also could be the systems of choice in remote regions, ice-covered
areas, and regions of heavy weather.

* Data management, educational outreach, and training in support of global science
endeavors. The prospect of embarking on global studies brings with it the obvious need
for mechanisms by which we can manage previously unimagined volumes of data. The
opportunities to link data collection with educational efforts are easily envisioned for
global studies. Infrastructure to facilitate such efforts exists in part through various
agencies programs to promote education at the K-12 level and as research opportunities
for undergraduates and graduate students. In addition to those foreseeable today, we
realize that there will be a continual need for "technological refreshment" to
accommodate future scientific needs over the next decades. This will enable us to
maintain and upgrade systems and to provide mechanisms for training technicians to run
the systems in the future.

Technology Needs for Global Science: A detailed list of the identified technological
needs is given in Appendix 1 and shown in Table 1.

E. Expeditionary

Expeditionary research, as meant here, refers to that which requires the deployment of any submergence assets to "geographically remote" parts of the globe. It can be defined in terms of two approaches, (1) mature and fundable but logistically difficult research and (2) high-risk research or field programs in previously unexplored regions.

The first of these involves field programs that are proposed for what would be considered geographically remote regions under the currently existing scheduling and funding paradigm (e.g., other than the East Pacific Rise and the Juan De Fuca). This has become particularly problematic as a consequence of the burgeoning success in time-series research. In practice, under the current situation, research that is based on mature field work (sufficient background information to justify the use of submergence assets and is highly recommended by reviewers based on its scientific merit) has little chance of being granted support from funding agencies unless a critical mass of proposals for that region is also highly ranked. Even those so highly ranked that they are granted funding are not being scheduled because of pressure to keep the assets in what has come to be termed the time-series "Yo-Yo." This situation underscores the insufficient access to submersible assets for accomplishing highly-ranked and even some funded submersible science.

Research that focuses on new territories or processes or that contains an element of discovery and is potentially scientifically high-yield may require new technology, tends to be interdisciplinary, is sometimes supported by circumstantial a priori data (i.e. multibeam, altimetry, SOSUS, cable breaks, etc.), but sometimes has little or no pre-existing data. The approach that is most useful in such areas is a nested mapping and sampling approach employing a full suite of multi-scale mapping/imaging tools combined with sophisticated sampling and in-situ sensing. New mapping systems on ROV platforms may be needed to fill in the gap between regional mapping tools and high-resolution mapping for small areas. The nested approach would be important in bringing previously unexplored areas up to the level of the mature field program. If such an approach is not possible, the alternative is to use portable, flyaway, lower-cost tools on ships of opportunity to produce a less comprehensive, but sufficient data set.

Critical Issues Related to Expeditionary Science.
 

* Access to appropriate vehicles: The principle factor impacting the ability to engage in submergence research in remote areas is the lack of access to the needed technologies (vessels, vehicles, etc). Such work is logistically expensive unless other work is scheduled in the same region. Within the existing constrained resources and scheduling process, time-series and observatory work fundamentally conflict with expeditionary science. Duplicating or complementing the existing submergence capabilities (i.e. Atlantis/Alvin, Argo/Jason, etc) would permit more expeditionary work. Such a solution is very unlikely without new influx of funding for submergence vehicles and tools. Gaining access to foreign assets, either for the expeditionary work or to fulfill the commitment to the time-series work would ease the pressure on existing vehicles and vessels. International and interagency involvements that mitigate the logistic and scheduling issues and enhance collaboration would extend the geographic range of scientific expeditions, but these historically have proven to be logistically difficult, require long-range planning, and involve the establishment of collaborative agreements. Developing partnerships with industry could provide access to additional assets.

* Implications regarding observatories: A conscious decision on the part of funding agencies to plan and budget support for observatories, as they are established, could be made so that they do not impose additional constraints on the ability to do expeditionary research. Linked proposals can be encouraged, both within and external to the submergence science community, that support efforts in remote areas. The development of submergence assets that are to be dedicated to observatories (AUV systems, for example), would both serve the specific needs of the observatory and free up traditional assets for use in other areas. The development of lightweight, portable tools (ROVs and/or AUVs) that can be transported inexpensively and can perform surveying and sampling for preliminary efforts in a high-risk area would provide a means to initiate the nested approach to expeditionary research. These tools could both stand on their own and could provide scientific justification for later commitment of the traditional submergence vehicles and tools.

* Coping strategies: Assuming the current funding and scheduling paradigm is not going to change, there are really only two alternative approaches. An investigation in a remote part of the world should employ all of the most sophisticated tools, thus ensuring maximum return, as it may not be possible to return for a long time, if ever. One of the most successful approaches used to-date in submersible exploration of any site is the application of a full suite of tools consisting of nested complementary systems that let the investigating team go from broad-area reconnaissance to site-specific measurement and sampling in a single expedition. This approach permits science objectives that are risky and have a significant component of discovery to be accommodated within the scope of hypothesis-driven inquiry. Multidisciplinary coordination of efforts that capitalizes on all capabilities of the assets and maximizes the knowledge returned would yield the greatest return. In order to accomplish this type of approach the community could be encouraged to design linked proposals that make it cost effective to take a ship to distant or logistically difficult regions. This may require a degree of direction from the agencies that is not customarily followed under the existing "science-driven" funding paradigm.

If additional vehicles were made available to the science community an entirely different set of constraints would apply. The community would have more chances to go to logistically remote locations for reconnaissance studies if there existed a less expensive, portable capability that could provide preliminary survey and sampling capability from vessels that did not have to transit long distances from US ports.

If it were possible to alter the existing funding/scheduling paradigm, then funding agencies and appropriate science advisory groups (e.g., various UNOLS advisory panels, proposal review panels, etc.) could encourage regional efforts (through the funding of planning workshops, for instance), review highly-ranked proposals for appropriateness of applicability of the requested submersible vehicle(s), and require the PIs to use alternatives if deemed advisable.

* New technologies: We can infuse new technologies into our existing funding and scheduling environment to increase the effectiveness of available ship time. AUVs, deployed in parallel with occupied submersibles or ROVs can fulfill this role. Improved sampling, imaging, and mapping capabilities for our existing vehicles, particularly ROVs would also be helpful. A seafloor mapping capability intermediate in resolution between the existing regional systems (hull-mounted or towed) and the high-resolution, site specific deep-towed ROV mapping. The development of additional portable, flyaway vehicle systems that allow reconnaissance work using ships with minimal positioning and cable-handling abilities would enhance the ability of investigators to develop programs for remote areas. The, development of such systems would permit the researcher to amass sufficient background data when needed to justify deployment of a full suite of traditional nested vehicles and tools. In some cases, sufficient data sets could be acquired to test basic models and hypotheses. New systems can offer cost-efficiency and remove the pressure from vehicles needed for seafloor observatories and time-series measurements. Using ships of opportunity, possibly including foreign vessels, sometimes in collaborative mode with submergence vehicles of foreign institutions sparks the international collaboration that could strengthen a given scientific program and enable proponents to improve the success rate of proposals to use a more comprehensive approach with nested systems. Taking this approach would permit spin-off components of the nested system to be engaged in more versatile and lower-cost methods of utilization. Portable, less expensive tools could consist of the following:

·        AUVs, possibly supplemented by acoustic or fiber-optic links. These AUVs would have mapping, imaging, and sampling capabilities

·        Lightweight TV-guided rock drill (CTD wire, can take a 1 meter oriented core)

·        TV guided grab

·        Lightweight, more portable ROVs and towsleds

·        Small submersibles for shallow-water work

Needs for Expeditionary Science: A detailed list of the identified technological needs is given
in Appendix 1 and shown in Table 1.

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IV. INFRASTRUCTURE AND FUNDING 

The workshop participants were asked to grapple with problems of infrastructure, funding, and
education during both the science and technical sessions of the workshop. The final half-day
included a plenary discussion of these complicated issues. The attendees agreed that in order to
accomplish the scientific goals defined during the initial workshop sessions, the submergence
science community requires greater access to a broad scope of ocean environments with a range
of safe, reliable, multi-faceted, high-resolution vehicles, sensors, and samplers operated from
support ships with global reach and station-keeping capabilities in all weather. It was recognized
that there are serious impediments to funding for multi-disciplinary science and for global,
time-series, or long-term observatory work. Education of the public, our fellow scientists, and the appropriate science advisory groups with regard to the advances in and potential from
submergence research will be critical to the success of the recommendations from this workshop.

The attendees agreed that the fundamental requirement for advancing submergence science is the
need to provide a dedicated national initiative to increase spending for submergence facilities
support and technology. This is the only way to ensure the needed access, facilities infrastructure,
and technology required to meet the challenges and requirements of submergence research in the
coming decades. Generally the development of these types of infrastructure and technology takes
5 to 10 years thus planning and budgets for this must begin immediately.

Increasing Availability of Assets: The clear and resounding message from the workshop
participants is that there is a severe problem with availability of submergence assets to the
research community. Vehicles required to service far-flung observation sites and those needed in
global surveys are difficult to integrate with other research operations. These factors dictate that
the community should use existing assets more effectively as well as take measures to increase the number of available vehicles. In particular, any new programs (e.g., OSN, Observatory MRE)
that would require additional vehicle services should include this factor in their funding plans so
that assets are not removed from other needs.

An example of the manner in which assets could be more effectively used is that manned
submersible operations in the upper oceans (<1500 m) could be carried out in a more economical manner via vehicles designed for such operation, rather than by their more expensive deep-diving
counterparts. Similarly, less costly special purpose vehicles should be used when possible. This
not only applies to planning efficient operations, but also to encourage the use of specialized, less
expensive equipment to perform tasks in traditional work areas (e.g., Juan De Fuca Ridge) in
order to liberate general purpose platforms for use elsewhere.

Finally, it should be recognized that the community needs a variety of unmanned work and survey
vehicles. These should be available in ways that are flexible to schedule and economical to
operate. A variety of institutions should operate these vehicles in order that the development of
new capabilities be stimulated and driven by close coupling to specific science needs.

These circumstances lead to a requirement to use all of our submergence assets effectively in a
coordinated mode that is well matched to the wide range of science needs. The "Global"
discussion group, in considering this matter, recommends a UNOLS-type coordination model
and corresponding funding mechanism be adopted in relation to operation of major submergence
facilities. A similar recommendation was a major thrust of the 1992 Deep Submergence
workshop as stated in the Executive Summary of the 1994 report "The Global Abyss."

Strategies for Enhancing Diversity of Assets: Many of the desired submergence capabilities
do not now exist, or are available only in developmental form. The necessary innovation to bring
these capabilities into operational status for the academic community are at present only
supported through the limited funding available in the NSF Oceanographic Instrumentation
Development program or in connection with special focus ONR programs. Greater innovation
can be enhanced by new funding initiatives. The outputs from this workshop could well be the
basis for generating a Submergence Assets Major Research Equipment initiative in NSF. Some
elements (e.g., AUVs plus their docking facilities for deployment in areas of interest) might wisely
be included in the projected Observatory MRE as well. Planning for such long-term programs
such as the Ocean Seismic Network or seafloor observatories, could also include provision for
submergence assets such as new ROVs or occupied submersibles required for system installation
and servicing

Supporting the submergence needs for global science in addition to demands for time-series
science, observatory science, and exploratory science, will require major investments in the
infrastructure for submergence science -- probably at the level of many millions of dollars. They
will be required to address two key aspects to increase investigator access to submergence assets 1) enhanced diversity and enhanced availability of these assets, and 2) they will probably require a reorganization of the current management structure for U.S. submergence science.

 Specific Session Suggestions: 

The individual science and technical sessions defined additional requirements and made
suggestions as to how to achieve solutions to the principle requirements.

* The Abyss and Open Ocean group noted that, as technology becomes more sophisticated, there will be an increasing need to provide ships using submergence vehicles with engineering and technical support. The ideal model is that afforded by the use of SeaBeam technology whereby the technical support and the instrumentation is provided to scientists rather than each being required to bring his or her own.

* The Event Response group suggested that if UNOLS ships were generally equipped with AUVs, it would be helpful if such ships were encouraged to participate in response efforts, even if only to steam to site, drop an AUV, and return to their original project work. Mechanisms for rapid funding of pre-approved commercial vessels need to be designed and implemented.

* The Short Time-series group recognized a serious shortcoming in the availability of submergence assets through normal NSF channels. In the case of assets for work at less than 1500 meters, the shortcoming is especially severe. There are several alternative scientific US occupied submersibles, and a large number of ROVs that are available and appropriate for use for much of this work. In some cases these alternative assets are more appropriate than any of the assets of the National Deep Submergence Facility. However, the mechanisms for funding these assets as part of an NSF research proposal are perceived to discriminate heavily against the use of these alternative assets. This group recommends a serious effort be made to investigate a mechanism where by other occupied vehicles and ROVs can be funded (e.g., by facility and not core funds) so neither reviewers nor program managers will weigh the cost of the facility against the proposal (as is perceived to be the case currently). The group suggests that the HBOI Johnson Sea Links, HURL PISCES V, and ROPOS would be excellent test cases to establish an appropriate mechanism for funding the most appropriate submergence asset for the particular science project.

* The Long Time-series group emphasizes that time-series science requires commitment, protection, standardization, and benchmarks. Measurement of long time-series phenomena requires decadal and longer commitments of investigators, assets and funding, possibly placing severe constraints on scheduling of ships and submersible assets. Such a commitment is difficult to institutionalize, given current methods of funding and scheduling and competition for resources. Measurement of long time-series phenomena require that the environment being measured be protected for the duration of the study. For example, a long-term study of a particular hydrothermal vent would be severely compromised if the vent were to be destroyed by a mining operation.

A key concern of the Long Time-series group is the response to failures of observatories. The current scheduling of submersible assets with the high demand for their use normally results in a substantial delay from the time of an identified need for an asset to its actual use. When responding to failure in an observatory, a long delay could be devastating to a time-series measurement, potentially degrading the data from many experiments. The numbers of assets, particularly high-capability ROVs, will need to grow during the next five years, and the methods of scheduling will need to be modified to include the possibility of rapid response to both emergencies and to science opportunities. It may be possible to prioritize scheduling to accommodate these types of events in similar ways.

As the number of experiments at an observatory grows, the complexity of management and safety considerations on the ocean floor will increase. Any initial design should include planning to ensure the safety of experiments and the assets that service the system. For example, at cabled observatories, cables should be laid on predetermined paths to minimize cross-overs and can be labeled with bar codes or other identifying marks.

Obtaining long time-series data from remote sites will place even stronger demands on the existing assets. To minimize the impact, observatories in environmentally difficult and remote areas must be as self-sufficient as possible and servicing should be required no more than once per year. It is not obvious that the buoy technology required for reliable installation and operation of such observatories is available, particularly for ocean bottom observatories in the Southern Ocean.

* The Coastal and Polar group expressed concern that this workshop was underrepresented by many ocean scientists who work in shallow or remote seas or lakes, owing to the erroneous perception by members of the shallow submergence science community that the shallow water aspect of the DESCEND workshop was to focus on DESSC (DEep Submergence Science Committee - the UNOLS subcommittee that provides oversight for the National Deep Submergence Facility) issues. Coastal and Polar group recommended that the scope of facilities supported as such be broadened and that UNOLS revise DESSC priorities to more closely represent the wider breadth of submersible priorities for ocean science. Specifically, they recommend the following:

·        Acquire additional assets to support a broader spectrum of submersible science,

·        Reconfigure of DESSC to SSC (Submersible Science Committee) to broaden the scope of representation and advisory activities,

·        Encourage deployment of submergence resources more equitably across world ocean environments,

·        Foster partnerships with industry to encourage technology development,

·        Endorse inter-/intra-agency technology transfer to accelerate development and distribution of submersible science technology,

·        Promote education and training of personnel in submersible science technology

The UNOLS DEep Submergence Science Committee has initiated action that will incorporate a representative of the shallow water community on DESSC with the goal of providing liaison between the deep and the shallow water submergence communities. The community of investigators involved in shallow oceanography, however, merit a focused committee that can serve as an advocate for facility needs within the UNOLS system and provide guidance to the federal agencies.

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V. Key Recommendations 
 

1) The oceans remain a frontier of science; this frontier has broad and rich societal and academic relevance, from understanding the role of the oceans in moderating global change to understanding the very limits of life on this and other planets.

2) Recent escalating advancements in submergence technologies (submersibles, ROVs, AUVs sensors, samples, etc.) provide unprecedented access to the oceans, with astounding promise for further advancement hampered not by imagination or need but by funds.

3) US leadership in submersible science and technology is in jeopardy in the absence of a dedicated national initiative to support increased access to existing submergence assets and to support technological developments.


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Table 1
(Table 1 is an Adobe Acrobat document.  Click below to view.)

Matrix of Technical Needs

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Appendix I:   Summary of Specific Technological Recommendations
 
 

Summary of Specific Technological Recommendations

The majority of participants agreed that there is a continuing need for human-occupied submersibles. The occupied submersible affords the researcher a currently unparalleled perspective on submarine environments, structures, and biological communities. The occupied submersible is a more robust vehicle, with greater power than most of the existing ROV systems and all of the AUV systems and is currently a more versatile tool than either. Until such time as the ROV and AUV technology can effectively mimic the human presence, there will continue to be a need for submersibles capable of taking the scientist into the submarine realm. The participants reviewed the current and potential requirements for improvement in technologies for submersible vehicles and tools. The participants in each technical session provided a list of identified needs in terms of technological improvements to these vehicles and systems. These lists follow:

Summary of Technological Needs for Event Response:

- In situ Sensors:

·         optical and chemical

·         probes for detailed chemical gradients

·         hi-temp probes

- heat flow probe

- probes for measuring long-term non-degradable signals (new anti-fouling methods) e.g.: H2, pH, Eh, metals, sulfide, POC, DOC, bio-(DNA-chip),

- Fluid Samplers: small (AUV) to large (ROV) volume, sample number/dive, manifold; profiling

- High Resolution Imaging

- Soft Sediment and sand/rock coring

- Payload: versatility, interchangeability

- "Smart" rocks (to follow sediment transport)

- Sample preservation capability (e.g., fixatives, freezing, maintaining in situ pressures)

- Fauna/larvae samplers (e.g., slurp, larval pumps)

- Manipulators with greater dexterity and capability

- AUVs: limited manipulation (maybe simple releasable hooks)

- ROVs: Dexterity (fine scale and delicate sampling/ manipulations of in situ experiments or sample preparation)

- Power: extend battery life/bottom time; advance battery technology;

- Data storage improvements

- Communication: cable (ROV, "HUGO" or "NEPTUNE" network docking stations); acoustic and/or radio telemetry

- Survey capabilities: bathymetry, magnetometer, acoustic backscatter, sub-bottom profiler, CTD-optical (water column)-rosette, photomosaics, gravimetry

- Navigation: up to meter scale or better;

- Simultaneous multi-vehicle navigation (modification of present transponder net navigation systems); self-contained navigation for drop-in AUVs
 

Summary of Technological Needs for Short Time-Series Science:

- Deep (6500+m) submersible vehicles

- Standardized tools for use on various platforms or with various submergence vehicles/tools

- Sensors: chemical and physical (may require longer support periods than usual 2-yr grant to develop)

- Devices to measure pore-water flow

- High definition digital video cameras with telemetry system and high quality lens.

- Support equipment for high-definition cameras/ IE recorders/ monitors; includes conversion equipment from high definition to more user-friendly format.

- Simple camera controllers for scientific observer operation

- Smooth, variable speed pan & tilt with simple controller

- Electronic/digital still cameras with large storage capacity

- Red light operation for biological purposes

- More precise, programmable, manipulators with feed-back capability for gentle handling

- Computer controlled sediment profilers

- Gas-type manifold for water column sampling

- Improved corers for coarse and hard sediments (vibra-corers?)

- Better seafloor drilling capability (from submersible vehicles and with sea-floor rigs)
 

Summary of Technological Needs for Long Time-Series Science:

- generic manipulators and vehicles

- standardization of electrical and optical connectors and power interfaces

- improved benchmark technology to provide mm accuracy for extended periods

Observatory science:

- Established of observatories on the seafloor

- New more robust ROV system with heavy lift capability, long bottom time, and dexterity in manipulation.

- generic submersible interfaces that allow use of a number of assets for the same task.

- flexibility in ability to down-load at various data rates, take up power, and interact with control systems

- dedicated, docked AUVs for collection of data beyond the spatial extent of an observatory and for rapid response to transient events

- recommended minimum suites of sensors for observatories
 

Summary of Technology Needs for Global Science:

- Matching vehicle types and instrument suites to the particular range of tasks at hand will be essential to the science- and cost- effective overall use of submergence assets present and future

- both water-column and seafloor vehicles

- benthic crawlers

- AUVs that fly above the seafloor.

- vehicles that can go to depths of 6000m or more

- a significant need exists for vehicles that operate efficiently in the upper 2000 m

- wide range of time and distance endurance for vehicles

- exploratory vehicles (possibly cheap, simple, with minimal capabilities)

- specialized vehicles for specific tasks

- sensors for pressure, temperature, magnetization, gravity, and light

- multi-spectral sensors (e.g., low-frequency radiation)

- current and flow sensors.

- chemical sensors both long range and for detailed site-specific work

- acoustical and optical sensors with varying ranges and resolutions both on the bottom and in the water column.

- high-definition video and photography

- in-situ X-ray imaging.

- better sampling devices for water, geological materials, sediment cores, and biological material. - - maximum capacity for multiple samples

- samplers that avoid cross-contamination

- samplers that retain in situ conditions

- sampling modes that enable coring and drilling for subsurface samples

- suction collectors with multiple chambers,

- enclosure-type samplers for especially fragile samples.

- small volume water sampler

- these sampling and sensor issues require improved dexterity of manipulators,

- advancements in communication and data transfer mechanisms, and power, payload, propulsion, and structural materials of platforms.

- technology training and networking to maintain and upgrade systems

- short baseline navigation of vehicles relative to their GPS-positioned tending ship may in some cases be an operationally preferable option.

- systems that can withstand environmental extremes (strong currents, caustic environments, high temperatures, high salinity, etc.

- weather constraints (e.g., polar environments) may require new support ship designs.
 
 

Summary of Technology Needs for Expeditionary Science:

- Very long range AUVs, expand on the ALTEX model to include other approaches such as gliders and solar-powered AUVS

- Air drop AUVs and navigational infrastructure

- Multiple AUVs

- AUVs with sampling capabilities

- Molecular and biochemical probes and sensors

- In-situ mass spectrometers

- AUVs with fiber or acoustic links

- More portable ROVs and towsleds, supported by improved, lightweight cables that can provide adequate power with smaller diameter cable.

- More intelligent AUVs

- Expendable AUVS

- Improved navigation

- Portable observatories

- Improve our abilities to produce rigorous data sets that allow others to explore after the expedition has ended.

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Appendix II:

Meeting Agenda

DEveloping Submergence SCiencE for the Next Decade: "DESCEND"
Scientific Challenges, Technology Developments, and Management Strategy

National Science Foundation
4201 Wilson Boulevard
Arlington, VA
October 25-27, 1999

Monday, October 25th,

Day 1: Science Discussions

 8:30 a.m. Open Meeting (Room 375)

·         UNOLS Welcome/Introduction - Dr. Thomas Royer, UNOLS Vice Chair

·         Overview DESCEND – Dr. Patricia Fryer

·         Overview of Submersible Science – Dr. Daniel Fornari

·         Observatory Science Overview – Dr. Keir Becker & Dr. John Delaney

·         Charge to Participants/Workshop Groundrules – Dr. Patricia Fryer

10:15 a.m. Breakout Sessions: Science Breakout Sessions:

12:00 Lunch

1:00 p.m. Reconvene Break-Out Sessions

3:45 p.m. Break

4:00 p.m. Plenary Session (Room 375) – Each session leader will provide a brief (one bulleted overhead) summary of their respective session. At the conclusion of all summaries there will be an open discussion.

6:00 p.m. Adjourn Day One

Tuesday, October 26th

 Day 2: Technology & Instrumentation

 8:30 a.m. Commence Day 2 (Room 375)

·         Overview of untethered systems – AUVs: Dr. James Bellingham

·         Manned and Unmanned Vehicles: Mapping: Dr. Dana Yoerger

·         Data Systems – Case studies within and outside of MG&G: Dr. Dawn Wright

10:15 a.m. Technological Breakout Sessions:

·         Event Response (Room 370) – Jim Cowen/Hugh Milburn

·         Time Series – Long (Room 360) – Fred Duennebier/Ross Heath

·         Time Series – Short (Room 390) – George Luther/ Marsh Youngbluth

·         Expeditionary (Room 375) – Dana Yoerger/Bill Ryan

·         Global (Room 375) – Fred Spiess/ Marty Kleinrock

12:00 Lunch

1:00 p.m. Reconvene Break-Out Sessions

3:45 p.m. Break

4:00 p.m. Plenary Session (Room 375) – Each session leader will provide a brief (one bulleted overhead) summary of their respective session. At the conclusion of all summaries there will be an open discussion.

6:00 p.m. Adjourn Day Two

Wednesday, October 27th

Day 3: Wrap-Up:

8:30 a.m. Commence Day 3 (Room 1235)

Morning: Future Technologies and Facilities: Developmental paradigms and tradeoffs – Dr. James Bellingham

A final plenary discussion among all participants will follow. A summary of the morning's discussion by the steering committee will close the workshop.

Afternoon: The afternoon will be set aside to allow the Steering Committee to complete writing assignments.
 
 

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Appendix III:

DESCEND Workshop
Steering Committee

 

CHAIR - Dr. Patricia Fryer, Professor
SOEST/Planetary Geosciences, University of Hawaii
pfryer@soest.hawaii.edu
***
Dr. Keir Becker – (Ocean Bottom Observatories) -
Marine Geology and Geophysics, RSMAS, University of Miami
kbecker@rsmas.miami.edu
***
Dr. Marv Lilley  - Chemistry
University of Washington
lilley@ocean.washington.edu
***
Dr. Craig Cary – Biology
College of Marine Studies, University of Delaware
caryc@udel.edu
***
Dr. Lisa Levin - Biology
Marine Life Research Group, Scripps Institution of Oceanography
Llevin@ucsd.edu
***
Dr. James Bellingham - AUV
Underwater Vehicles Laboratory, MIT Sea Grant Program
belling@mit.edu

 

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Appendix IV:


 

DESCEND PARTICIPANTS

To view the list of workshop participants click on:
DESCEND Participants
Abstracts submitted by participants can be viewed by clicking on his/her name.

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Appendix V:

DESCEND ABSTRACTS

Meeting participants provided abstracts in advance of the DESCEND workshop.  These abstracts are being complied and will be included on this page.  To view individual abstracts, see the participant list included as Appendix IV.

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Appendix VI:

Related Website Links

FUTURES Workshop Reports:

FUMAGES (MG&G) =>
http://www.joi-odp.org/FUMAGES/FUMAGES.html
http://www.joss.ucar.edu/joss_psg/project/oce_workshop/fumages/
FOCUS (Chemical Oceanography) =>
http://www.joss.ucar.edu/joss_psg/project/oce_workshop/focus/
OEUVRE (Biology) =>
http://www.joss.ucar.edu/joss_psg/project/oce_workshop/oeuvre
APROPOS (Physical Oceanography) =>
http://www.joss.ucar.edu/joss_psg/project/oce_workshop/apropos/
LExEn (Life in Extreme Environments) =>
http://www2.ocean.washington.edu/lexen/
 
 

Observatory Links:
http://vertigo.rsmas.miami.edu/deos.html
 
 

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