Showing papers in "Marine Technology Society Journal in 2004"

Underwater gliders for ocean research

Abstract: Underwater gliders are autonomous vehicles that profile vertically by buoyancy control and move horizontally on wings. Gliders are reviewed, from their conception by Stommel as an extension of autonomous profiling floats, through their development in 3 models, and including their first deployments singly and in numbers. This paper discusses the basics of glider function as implemented by University of Washington, Seaglider, Scripps Institution of Oceanography, and Webb Research in Slocum. Preliminary results are presented from a recent demonstration project that used a network of gliders off Monterey. A wide range of sensors has already been deployed on gliders, with many under development, and a wider range of future possibilities. Glider networks appear to be among the best approaches to achieving subsurface spatial resolution necessary for ocean research.

An ocean blueprint for the 21st century: the work of the u.s. commission on ocean policy

Abstract: The paper reviews the report of the U.S. Commission on Ocean Policy that reflects the input of hundreds of people from across the nation, testimony from many of the world's leading experts and months of deliberation. The report contains recommendations to set the course toward a future in which oceans, coasts, and Great Lakes are healthy and America's marine resources are restored and sustained for the future generations. Presented is a new national ocean policy that will balance ocean use with sustainability, that is based on sound science and supported by excellent education, and is overseen by a coordinated system of governance with strong leadership at national and regional levels.

Autonomous profiling floats: workhorse for broad-scale ocean observations

Abstract: The autonomous profiling float has been a revolutionary development in oceanography, enabling global broad-scale ocean observations of temperature, salinity, velocity, and additional variables. The Argo float array applies this new technology to provide unprecedented measurements of the global upper ocean in near real time, with no period of exclusive use. It builds on its predecessors, the upper ocean thermal networks of the 1970’s to 1990’s— extending the spatial domain and depth range, improving the accuracy, and adding salinity and velocity. Precision satellite measurements of sea surface height, as made by the Jason1 altimeter, combine with Argo data in a dynamically complementary description of sea level variability and its subsurface causes. The broad-scale Argo float array is a central element in the international infrastructure for ocean research. A comprehensive ocean observing system can be constructed from floats, together with satellite measurements, improved measurements of air-sea fluxes, moored time-series in the tropics and other special locations, shipboard hydrography, and high resolution measurements in fronts, eddies and boundary currents from autonomous gliders. One of the primary objectives of the observing system is to close the oceanic budgets of momentum, heat, and freshwater on seasonal and longer time-scales in order to understand the role of the ocean in the climate system.

Cabled ocean observatory systems

Abstract: The most capable ocean observatories are designed around a submarine fiber optic/power cable connecting one or more seafloor science nodes to the terrestrial power grid and communications backhaul. This paper defines the top level requirements that drive cabled observatory design and the system engineering environment within which a scientifically-capable infrastructure can be implemented. Commercial high reliability submarine telecommunication technologies which will be crucial in the design of long term cabled observatories are then reviewed. The top level architecture of a generic cabled observatory, describing the main subsystems comprising the whole and defining technological approaches to their engineering, is then described, along with some example design choices and tradeoff studies.

Exploring the deepest depths: preliminary design of a novel light-tethered hybrid rov for global science in extreme environments

Abstract: This work details a new effort to build an operational underwater vehicle that can perform scientific survey and sampling to the full depth of the ocean (11,000 m). The vehicle, called a hybrid remotely operated vehicle (HROV), will operate in 2 different modes. For broad area survey, the vehicle will operate untethered as a autonomous underwater vehicle (AUV) capable of exploring and mapping the seafloor with sonars and cameras. After targets of interest have been found, the vehicle will be converted at-sea to become a remotely operated vehicle (ROV) that will enable close up imaging and sampling. The ROV configuration will incorporate a lightweight fiber-optic tether to the surface for high bandwidth real-time video and data telemetry to the surface to enable highquality teleoperation, additional cameras and lights, a manipulator arm, and sampling gear. The paper outlines the scientific motivation for the project as well as feasibility of the design concept. Analysis of the fiber-optic cable shows the approach taken to be practical even with fairly extreme current profiles. An overall approach to the vehicle design is given, including options for pressure housings and buoyancy materials.

A national coastal ocean surface current mapping system for the united states

Abstract: This paper gives a description of a nationwide surface current mapping system for the U.S. continental shelf regions based on emerging capabilities of high frequency (HF) radar backscatter instruments. These have the advantages of being real-time, non-invasive, shore-based instruments capable of mapping ocean surface currents out to ranges of ~200 km from shore. A framework for a national backbone system is described based on long-range HF radar systems and example results are provided from existing arrays off the northwest and northeast U.S. coastlines.

A replacement for the alvin submersible

Abstract: The National Deep Submergence Facility (NDSF) has completed the conceptual development for a proposed new manned deep submergence vehicle that would replace Alvin. The new vehicle would dive deeper (6,500 m), have improved observer and pilot viewing, a larger interior volume with improved ergonomics, greater battery capacity with improved endurance, and less reliance on disposable weights and hazardous materials. A proposal based upon the conceptual design has been submitted to the National Science Foundation for consideration in 2004. Should this be approved, a new manned submersible could be available for use by the worlds oceanographic community early in 2008.

Satellite Data Assimilation for Improvement of Naval Undersea Capability

Abstract: Impact of satellite data assimilation on naval undersea capability is investigated using ocean hydrographic products without and with satellite data assimilation. The former is the Navy’s Global Digital Environmental Model (GDEM), providing a monthly mean; the latter is the Modular Ocean Data Assimilation System (MODAS) providing synoptic analyses based upon satellite data. The two environmental datasets are taken as the input into the Weapon Acoustic Preset Program to determine the suggested presets for an Mk 48 torpedo. The acoustic coverage area generated by the program will be used as the metric to compare the two sets of outputs. The output presets were created for two different scenarios, an anti-surface warfare (ASUW) and an anti-submarine warfare (ASW); and three different depth bands, shallow, mid, and deep. After analyzing the output, it became clear that there was a great difference in the presets for the shallow depth band, and that as depth increased, the difference between the presets decreased. Therefore, the MODAS product, and in turn the satellite data assimilation, had greatest impact in the shallow depth band. The ASW presets also seemed to be slightly less sensitive to differences than did presets in the ASUW scenario.

An integrated approach to ocean observatory data acquisition/management and infrastructure control using web services

Abstract: Proliferation of ocean observatories in the absence of agreed upon standards for instrument and user interfaces and observatory control functions will constrain interoperability/cross-linking of disparate datasets. In turn, this will limit scientific impact of ocean observatories and increase operating costs. Devising hardware-based standards will be difficult given the different internal architecture of existing and future ocean observatories. This paper proposes that instrument, data, and observatory control processes be wrapped with standard web services to yield a global software standard for the observatory functions. In addition to facilitating interoperability, state-full web services with workflow bindings for observatory instrument and data processes will enable dynamic user control of observatory configuration and the creation of multiple virtual instrument networks within 1 or more ocean observatories. These concepts are defined and illustrated through several use scenarios.

Science for Stewardship: Multidisciplinary Research on USS Arizona

Abstract: The National Park Service's Submerged Resources Center and USS Arizona Memorial are conducting and coordinating research directed at understanding the nature and rate of natural processes affecting the deterioration of the USS Arizona in Pearl Harbor, Ha- waii The USS Arizona Preservation Project is designed to be multi-year, interdisciplinary and cumulative, with each element contributing to developing an overall management strategy designed to minimize environmental hazard from fuel oil release and provide the basic research required to make informed management decisions for long-term preserva- tion The primary project focus is toward acquiring requisite data for understanding the complex corrosion and deterioration processes affecting Arizona's hull, both internally and externally, and modeling and predicting the nature and rate of structural changes This research program is designed to be a cumulative progression of multi-disciplinary investigative steps Multiple lines of evidence are being pursued simultaneously, each directly or indirectly linked to the others and to the overall project objectives This project is an example of government agencies, academic institutions, military commands and private institutions working together effectively for public benefit The USS Arizona Pres- ervation Project is designed to serve as a model because it will have direct application to preservation and management of historical iron and steel vessels worldwide and to inter- vention actions for other leaking vessels

The need for a proactive approach to underwater threats

Abstract: This article describes the role of the National Oceanic and Atmospheric Administration (NOAA) in evaluating environmental risks from underwater threats Underwater threats range from submerged shipwrecks, to abandoned wellheads and pipelines, to underwater dumpsites NOAA's risk evaluation requires determining what potential sites need immediate assessment or ongoing monitoring It must also be decided what types of user activities should be limited within a specific area due to their potential impact on underwater threats NOAA must also evaluate which areas merit protection as marine sanctuaries or essential fish habitats These risk assessment decisions must be made using all available information Two of NOAA's programs that share a mandate to provide the best possible information to protect and manage NOAA's trust resources are described: NOAA's Office of Response and Restoration and the National Marine Sanctuary Program These programs have initiated a database project to provide both baseline information on the broad range of underwater threats from vessels, and the information necessary to determine the potential environmental tradeoffs for areas of special environmental concern

Autonomous underwater vehicles for ocean research: current needs and state of the art technologies

Abstract: Research in the field of scientific Autonomous Underwater Vehicles (AUVs) has been underway for over 3 decades. Much of the original work was funded by the military, and the vehicles were intended for Naval Ordnance Systems Command oceanographic needs, although the payloads were for general scientific use. Over the last decade, several autonomous underwater vehicles have been purposely built for both the science community and industrial operations around the world. Because of the variety of mission requirements, AUV configurations and options available today are numerous. Beginning with a brief overview of the history of AUVs for science, this paper continues with discussion of the ocean applications that are suitable to AUVs. Highlighted are some points a potential user might consider when selecting an AUV for a particular science application. An overview of several AUVs available today has been included exploring the cross-section of capabilities offered. This leads into the emerging requirements for AUVs of the future. Conclusions offer insights on lessons learned by several members of the oceanographic AUV community and how these lessons might be applicable when considering AUVs as a solution to today's intriguing oceanographic science questions.

Abandoned vessels: impacts to coral reefs, seagrass, and mangroves in the u.s. caribbean and pacific territories with implications for removal

Abstract: The Abandoned Vessel Program (AVP) was implemented by the National Oceanic and Atmospheric Administration to investigate the problems posed by abandoned and derelict vessels on U.S. coral reef habitats. As part of this program, a subset of known abandoned derelict vessels in sensitive habitats was surveyed in U.S. territories in the Caribbean and Pacific in 2002-2003. Vessels were surveyed to determine current and potential impacts to benthic environments, particularly coral reef, seagrass and mangrove habitats. In all, 180 vessels were surveyed. Findings showed that the range of potential environmental implications varied. The majority of vessels surveyed in reef habitats were aground on hardbottom with low relief and low percentage coral cover, and therefore were not considered to be producing substantial environmental impacts. The few vessels that were aground on or near higher quality habitat and/or had extensive debris fields were of very high concern to the AVP and local managing agencies. If the potential environmental impact of these vessels is not addressed, further injury to surrounding habitats is likely. Damage to seagrass habitats also varied widely, but those vessels causing active erosion to seagrass beds, particularly when moved during storms, should also be considered a priority for removal. Although damage to mangroves were typically less substantial than to coral reefs and seagrass, impacts to mangrove habitats were common in areas where grounded vessels were clustered in sheltered bays.

Deepwater mooring designs for ocean observatory science

Abstract: This paper describes the current state-of-the-art in mooring systems appropriate to the deepwater ocean observatory context. The technological challenges that need to be addressed in order to realize moored ocean observatories as envisioned for the next generation of ocean observing systems are outlined.

European experience in response to potentially polluting shipwrecks

Abstract: As fuel powered engines became the norm in shipping, each shipwreck implied that some oil was spilled, while more was trapped in the wreck. Corrosion over time would release this trapped oil, creating a pollution hazard for future generations. This paper describes how consciousness of this problem developed in Europe and how a response strategy was established as a result of actual incidents. The response strategy was originally limited both by cost considerations and by the capacities of the existing underwater intervention technology. However, the successful recovery of the fuel trapped in a Maltese tanker demonstrated that oil recovery from a wreck has become technically possible at any depth. This leaves cost as the only remaining limiting factor, raising the question of how to identify the possible standards for weighing intervention costs against potential pollution hazards. Although several incidents are described, the lack of public potentially polluting shipwreck records makes it necessary to consider response standards only on a case-by-case basis. However, the case studies described here make it clear that response standards must reflect public opinion as well as the view of industry, governments and technical experts.

Quantified marine oil emissions with a video-monitored, oil seep-tent

Abstract: Identifying and quantifying sources of oil and seabed emissions are the first steps in assessing the need for and desirability of various mitigation strategies. This paper presents a new technique for quantifying seabed emissions--a diver deployed, video-monitored oil seep-tent that provided both real time and high time resolution monitoring of oil emissions, allowing assessment of variability. The oil capture tent was developed and deployed during two field trips to quantify oil emissions from several sites in nearshore waters off Summerland Beach in Santa Barbara County, California, at a water depth of about 5 m. The tent was a tall, inverted polyvinyl chloride plastic cone, which funneled oil into a video-observed sample collection jar. Sample jars were periodically retrieved and analyzed to determine oil and gas emissions at two seeps not associated with physical structures, and a suspected abandoned oil well, designated S-3. Video analysis, calibrated with collected and analyzed oil samples allowed a detailed time series of emission rates to be determined for investigation of sources of variability. Oil emission variations with a periodicity comparable to the swell were observed, as was a strong response at 120 seconds.

Ocean literacy is key to preserving our oceans and coasts

Abstract: The article reviews the effect of both the U.S. Commission of Ocean Policy and the Pew Commission reports on our understanding of the degrading condition of our oceans. It lists the following four goals in contributing to an 'ocean-literate' America: to invest in higher education in science and technology fields relevant to the oceans; to develop an ocean workforce and train individuals for productive ocean related careers; to build a solid framework for above goals by integrating ocean studies into elementary and secondary school programs; and to establish nationwide public outreach program and innovative education programs at museums, aquaria, science centers and other informal education sites.

Undersea pollution threats and trajectory modeling

Abstract: This article describes how two National Oceanic and Atmospheric Administration resources, the Resources and Undersea Threats (RUST) database and the Trajectory Analysis Planner (TAP), can be used together to provide more robust area contingency plans for undersea pollution threats. RUST was developed to inventory and assess potential threats from underwater sources of pollution. Undersea threat information is only the first step of several in determining the potential scope and scale of the spill trajectories that demonstrate potential to impact sensitive resources. Resource managers frequently have to make decisions based on the precautionary approach, using the best available information to weigh alternatives without knowing for certain whether they are making the right choice. In contrast, pollution responders are generally reactionary and response alternatives must be generated with the best available information. TAP was developed as a spill response and planning application, which randomly samples seasonal climatology and runs hundreds of possible trajectories. These trajectories are combined to form several modes that display various types of ocean analysis. Combining TAP modeling with the RUST database could provide seasonal probability pollution threat contours for each significant undersea pollution threat. This would provide marine resource managers with critical information for making planning decisions and for developing preparedness and response operations.

Global offshore hazardous materials sites gis

Abstract: This paper discusses the history of hazardous materials disposal and loss at sea, primarily off the United States coast between 1945 and 1970 when few guidelines existed to geographically document an underwater site. A geographic information system (GIS) project is described that documents the locations and associated data of Global Offshore Hazardous Materials Sites (GOHMS) potentially posing threats to human health, safety, navigations, commercial fishing and the environment. Nearly 350 sites are currently in the project. Although not publicly distributed at present, the GOHMS GIS project is intended to add value to existing historical information by providing easy access to waste stream locations and other spatial data through the National Oceanic and Atmospheric Administration's Office of Response and Restoration and the National Marine Sanctuaries Program. GOHMS represents one approach to promoting the integration of information products derived from different marine technologies in order to provide a complete picture of the underwater environment.

Potentially polluting wrecks warrant further dialog

Abstract: A disturbing pollution threat is posed by a large population of aging shipwrecks in various states of decay containing unknown volumes of oils, chemical and radiological substances. Efforts to mitigate or remove the pollution threat can be costly and complicated. This article describes two such wrecks, the freight ship SS Jacob Lukenbach, which sank in 1953, and the Navy oil tanker USS Mississinewa, which sank in 1944. The oil recovery operations for these vessels are highlighted. Since resources for recovery operations are limited, the potential harm from these wrecks must be weighed against questions of who has the responsibility, the will, the authority and the financial backing to address the threat. The varied dimensions of the shipwreck threat must be considered through a variety of perspectives, which will require continued and collective dialog among stakeholders.

Regional ocean governance: a critique of two recent proposals

Abstract: The article critiques the reports of two recent expert panels, the U.S. Commission on U.S. Ocean Policy and the Pew Oceans Commission. Both panels have focused their attentions on the marine environmental and resource management problems of the United States. Both panels have done a huge service to the nation by investigating, often in great detail, a wide assortment of problems relating to the use of the oceans in the United States and internationally. Yet the proposals of the two commissions are quite distinct. The Pew Commission recommends a top-down approach, with enforceable management plans would be developed by each regional council, followed by the imposition of zoning restrictions on human activities. The U.S. Ocean Commission-type regional governance can be characterized as moreof a bottom-up approach. In conjunction with stakeholders, states and other political entities would propose the formation of a regional council.