The Long-term Ecosystem Observatory: an integrated coastalobservatory

An integrated ocean observatory has been developed and operated in the coastal waters off the central coast of New Jersey, USA. One major goal for the Long-term Ecosystem Observatory (LEO) is to develop a real-time capability for rapid environmental assessment and physical/biological forecasting in coastal waters. To this end, observational data are collected from satellites, aircrafts, ships, fixed/relocatable moorings and autonomous underwater vehicles. The majority of the data are available in real-time allowing for adaptive sampling of episodic events and are assimilated into ocean forecast models. In this observationally rich environment, model forecast errors are dominated by uncertainties in the model physics or future boundary conditions rather than initial conditions. Therefore, ensemble forecasts with differing model parameterizations provide a unique opportunity for model refinement and validation. The system has been operated during three annual coastal predictive skill experiments from 1998 through 2000. To illustrate the capabilities of the system, case studies on coastal upwelling and small-scale biological slicks are discussed. This observatory is one part of the expanding network of ocean observatories that will form the basis of a national observation network     

Characteristics of acoustic propagation to the eastern vertical line array receiver during the summer 1996 New England shelfbreak PRIMER experiment

During July and August of 1996, the summer component of the New England shelfbreak front PRIMER experiment was fielded in the Mid-Atlantic Bight, at a site due south of Martha's Vineyard, MA. This study produced acoustic transmission data from a network of moored sources and receivers in conjunction with very-high-resolution oceanography measurements. This paper analyzes receptions at the northeast array receiver from two 400 Hz acoustic tomography sources, with the transmission paths going from the continental slope onto the continental shelf. These data, along with forward acoustic-propagation modeling based on moored oceanographic data, SeaSoar hydrography measurements, and bottom measurements, reveal many new and interesting aspects of acoustic propagation in a complicated slope-shelf environment. For example, one sees that both the shelfbreak front and tidally generated soliton internal wave packets produce stronger mode coupling than previously expected, leading to an interesting time-and-range-variable population of the acoustic normal modes. Additionally, the arrival time wander and the signal spread of acoustic pulses show variability that can be attributed to the presence of a frontal meander and variability in the soliton field. These and other effects are discussed in this paper, with an emphasis on creating a strong connection between the environmental measurements and the acoustic field characteristics.     

Quantitative evaluation of the time-line reduction performance in high definition marine magnetic surveys

The effectiveness of the time reduction procedure is the critical problem for the informative contents evaluation in the high definition (HD) geomagnetic marine surveys. The use of magnetogradiometers is a good solution for the time-reduction in the regional offshore studies but often, for technical reasons, this is not a practicable method in the very detailed coastal, canal or harbour surveys where the use of coastal base stations may be preferable. On the other hand the uncertainty of the full transferability of the coastal magnetograms to large areas of marine surveys can disrupt the time-reduced data sets by a geomagnetic residual time component. The phenomenon is related to the distance from the coastal observatory and to the homogeneity of the local magnetic characteristics of the crust. The maximum applicability distance of the time-line correction (TL) is qualitatively evaluated and is shown to be inconsistent with geomagnetic marine surveys in high definition. In this work we show a quantitative method to evaluate the stability of the coastal observatory magnetograms over the nearby marine area, together with the numerical degree of precision of the correction. The method is based on a double survey of the same profile (timer track: TT) at two different times. The surveys produce two different row data sets where the difference is related only to the geomagnetic time variations. Using the coastal observatory magnetograms we time-reduce the two data sets: if the coastal observatory magnetograms are fully coherent in the whole survey area the difference between the two reduced data sets will be zero. However, if the time variations measured in the observatory are inadequate in amplitude or phase to model the corresponding time variations in the surveyed profile (TT), the discrepancy between the time reduced data sets will not be zero. Similar TTs starting with various course from the base station permit the surveyed area to be split into sectors with variable degree of time coherence and to assign a degree of precision to the time-reduced survey.     

Coastal observatory for long-term measurement and real time data processing of oceanological parameters

A coastal observatory for long-term continuous measurements of oceanological parameters and real-time data transfer via the Internet to remote users is described. The observatory was designed at the Shirshov Institute of Oceanology (SIO) and tested at its southern branch (SB) in the Black Sea. The architecture, components, and design principles of the observatory are discussed along with its application for solving problems of water dynamics in the coastal zone. Results of field tests are given.     

An Acoustic-Instrumented Mine for Studying Subsequent Burial

The U.S. Navy is supporting the research to develop and validate stochastic, time-dependent, mine burial prediction models to aid the tactical decision making process. This research requires continuous monitoring of both mine behavior during burial, and the near-field processes responsible for burial. A new instrumented mine has been developed that far exceeds the capabilities of the earlier optically instrumented mine in terms of the burial processes that can be measured. The acoustic-instrumented mine (AIM) utilizes acoustic transducers to measure burial and scour, localized flow rates, and sediment size and concentration in the water column. The AIM also includes sensors for measuring mine orientation and movement, as well as oceanographic information such as significant waveheights, wave period, and water temperature. Four AIMs were constructed and deployed during the Indian Rocks Beach (IRB, FL) and Martha's Vineyard Coastal Observatory (MVCO, Edgartown, MA) mine burial experiments. The results from the field experiments have proven that the sensor suite is viable in providing a wealth of data that are critical in understanding and modeling the complex subsequent burial process.     

A coastal management program for channels located in backbarrier systems

Management of the interactions between social/economic interests and the coastal environment requires practical, interdisciplinary assessment techniques. Backbarrier systems are critical natural resources that provide both economic and social benefits. Activities such as aquaculture, fishing, shipping and port activities, sediment mining, salt extraction, and tourism all take place in these ecosystems but are often not compatible with each other. Therefore, a program to manage such a system must congregate many different types of activities and stakeholders with potentially conflicting interests. In this paper, we develop a proposed coastal management program (CMP), based on the driving-pressure-state-impact-response (DPSIR) framework and the integrated coastal management (ICM) cycle, for the management of channels located in backbarrier systems subject to dredging operations. The conceptual model involves the application of regional sediment management (RSM) actions and is applied to a case study, Faro Channel, located in the Ria Formosa backbarrier system in Algarve, Portugal. The CMP provides results on the interactivity between scientists, stakeholders, and decision-makers, by defining and clarifying the economic and environmental aspects of decision-making processes through the utilisation and measurement of local coastal indicators. The proposed CMP proved to be a useful tool in the definition of coastal management initiatives for channels inside backbarrier systems, since it identified management problems and allowed management solutions to be formulated. The CMP could be used within a broader ICM program but would also be effective when used on its own.     

Predicting Seabed Burial of Cylinders by Wave-Induced Scour: Application to the Sandy Inner Shelf Off Florida and Massachusetts

A simple parameterized model for wave-induced burial of mine-like cylinders as a function of grain-size, time-varying, wave orbital velocity and mine diameter was implemented and assessed against results from inert instrumented mines placed off the Indian Rocks Beach (IRB, FL), and off the Martha's vineyard coastal observatory (MVCO, Edgartown, MA). The steady flow scour parameters provided by Whitehouse (1998) for self-settling cylinders worked well for predicting burial by depth below the ambient seabed for (0.5 m) diameter mines in fine sand at both sites. By including or excluding scour pit infilling, a range of percent burial by surface area was predicted that was also consistent with observations. Rapid scour pit infilling was often seen at MVCO but never at IRB, suggesting that the environmental presence of fine sediment plays a key role in promoting infilling. Overprediction of mine scour in coarse sand was corrected by assuming a mine within a field of large ripples buries only until it generates no more turbulence than that produced by surrounding bedforms. The feasibility of using a regional wave model to predict mine burial in both hindcast and real-time forecast mode was tested using the National Oceanic and Atmospheric Administration (NOAA, Washington, DC) WaveWatch 3 (WW3) model. Hindcast waves were adequate for useful operational forcing of mine burial predictions, but five-day wave forecasts introduced large errors. This investigation was part of a larger effort to develop simple yet reliable predictions of mine burial suitable for addressing the operational needs of the U.S. Navy.     

Study on 10 kVDC powered junction box for a cabled ocean observatory system

A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current (kVDC) with up to 10 kW power, along with 1 Gigabit/sec Ethernet communication, can be transmitted from the shore to the seafloor through an umbilical armored cable. A subsea junction box is fixed at a cable terminal, enabling the extension of up to nine connections. The box consists of three main pressure vessels that perform power conversion, power distribution, and real-time communication functions. A method of stacking modules is used to design the power conversion system in order to reduce the 10 kV voltage to levels that can power the attached instruments. A power distribution system and an Ethernet communication system are introduced to control the power supply and transmit data or commands between the terminals and the shore station, respectively. Specific validations of all sections were qualified in a laboratory environment prior to the sea trial. The ocean observatory system was then deployed at the coast of the East China Sea along with three in situ instruments for a 14-day test. The results show that this high voltage-powered observatory system is effective for subsea long-term and real-time observations.     

International law considerations for owners and operators of cabled and buoy observatories

Numerous undersea observatories using cables or buoys are being planned and implemented by scientists and engineers. These projects are being planned with service lives measured in decades. The geographic reach of these systems extends beyond national waters and well into the high seas. Procurement and maintenance of these systems must be cost effective if they are to realize their scientific goals. This objective can be enhanced if the scientists and engineers designing, building, and operating these systems do so with awareness of the responsibilities, liabilities, and advantages accorded marine scientific research under international and maritime law. Generally, these subjects are addressed in the United Nations Law of the Sea Convention 1982 (UNCLOS), as it is supplemented by appropriate national law. This paper provides a basic overview of applicable international law. For purposes of showing the relationship between UNCLOS with national law, U.S. law is utilized, although many nations have similar approaches in their domestic law. In planning an undersea observatory system, a complete and timely analysis of the national law of jurisdictions with a factual nexus to the system is recommended at the earliest stages.     

Mine Burial Observations During the 2003–2004 U.S. Office of Naval Research Experiment

During the 2003-2004 winter season, the U.S. Office of Naval Research (ONR, Arlington, VA), sponsored a detailed in situ study of the mine burial process resulting from wave-seafloor-mine interaction at Martha's Vineyard Coastal Observatory (MVCO, Edgartown, MA). In total, 16 mine shapes were deployed. Six were the Forschungsanstalt der Bundeswehr fur Wasserschall und Geophysik (FWG, Kiel, Germany) burial registration mines using optical sensors, four others were equipped with acoustical sensors, and six were simple shapes. Repeated acoustic surveys and detailed sediment sampling were conducted to characterize the site and the burial status of all objects. This paper focuses on data from three recovered optical systems. The records show three roll events at all three registration mines, which are necessary for scour burial. Two systems experienced a fourth roll event. Results from earlier experiments suggest only three (four) stages of progressively increasing burial despite frequent successive burial and exposure cycles (some as short as 1 h). During these burial-exposure cycles changes of buried mine volume reached up to 80%. The only reasonable explanation is a change of sediment height of up to 40 cm relative to the stably lying mines. This requires new concepts. Cyclic burial changes that were observed simultaneously at different positions cannot be explained with existing models. The least difficult explanation is ldquounderwater sand stormsrdquo which are characterized by a high sediment suspension.     

Real-time geophysical measurements on the deep seafloor usingsubmarine cable in the southern Kurile subduction zone

A permanent real-time geophysical observatory using a submarine cable was developed and deployed to monitor seismicity, tsunamis, and other geophysical phenomena in the southern Kurile subduction zone. The geophysical observatory comprises six bottom sensor units, two branching units, a main electro-optical cable with a length of 240 km and two land stations. The bottom sensor units are: 1) three ocean bottom broadband seismometers with hydrophone; 2) two pressure gauges (PGs); 3) a cable end station with environmental measurement sensors. Real-time data from all the undersea sensors are transmitted through the main electro-optical cable to the land station. The geophysical observatory was installed on the continental slope of the southern Kurile trench, southeast Hokkaido, Japan in July 1999. Examples of observed data are presented. Sensor noises and resolution are mentioned for the ocean bottom broadband seismometers and the PGs, respectively. An adaptable observation system including very broadband seismometers is scheduled to be connected to the branching unit in late 2001. The real-time geophysical observatory is expected to greatly advance the understanding of geophysical phenomena in the southern Kurile subduction zone     

海上警戒浮标实时监控系统

为有效保护近海海底观测网观测安全,免受渔船拖网和抛锚等损坏的问题,设计了一套多警戒浮标(直径2.4~3.0 m)的实时监控系统,该警戒浮标可获取浮标本身工作状态,并能实时、动态、连续的将警戒浮标的运行状态发送到陆基岸站,实现对保护目标海域的实时监控,同时该浮标系统可进行扩充实现对海洋环境要素的观测。警戒浮标布设采用正多边形(三角形、正方形和正五边形等)预警保护方式,浮标以保护节点为中心等距布放,组网形成有效的海上保护围栏,保障海底观测系统的安全运行;供电系统采用太阳能电池和蓄电池组合供能方式,可保证在连续阴天的情况下警戒浮标系统运行100天。该警戒浮标技术已在东海海底观测网保护中成功示范运行6个月,该技术可为近海海底观测保护提供有效技术保障。     

Scientists’ prioritization of global coastal research questions

Complex coastal management challenges often span ecological and political boundaries, and involve competing demands from groups advocating alternative coastal management strategies. As a consequence, policy-makers require scientific evidence from across a range of disciplines. Implementing cross-disciplinary research and facilitating science-policy engagement are, however, a significant challenge in its own right. Seven recent ecologically oriented ‘big question’ exercises identified a variety of research questions potentially important for coastal and marine management. In this research, 592 coastal scientists from 91 different countries completed a survey that ranked those 20 coastally oriented research questions. There was a clear overall ordering of aggregated coastal research priorities but scientists did exhibit heterogeneity regarding priorities. Some prioritized ecological issues while others focused more on issues such as coastal resource use or global environmental change. The differences in opinion were largely disciplinary-based, highlighting the importance of, and challenges in, encouraging scientific collaboration across disciplines to support effective coastal zone management. In addition to the ranking of existing questions, scientists submitted an additional 340 potential priority research questions, thus broadening the participatory nature of the original exercises. New questions regarding coastal processes, contaminants and pollution, and monitoring were prominent. This first synthesis across ‘big question’ exercises should provide valuable insights into the diversity of scientists’ opinions and help policy makers understand potentially conflicting science advice.     

Numerical Simulations of the Flow and Sediment Transport Regimes Surrounding a Short Cylinder

The 3-D flow field and bed stress surrounding a short cylinder in response to combined wave and mean-flow forcing events is examined. Model simulations are performed with a 3-D nonhydrostatic computational fluid dynamics model, FLOW-3D. The model is forced with a range of characteristic tidal and wave velocities as observed in 12-15 m of water at the Martha's Vineyard Coastal Observatory (MVCO, Edgartown, MA). The 2.4-m-long and 0.5-m diameter cylinder is buried 10% of the diameter on a flat, fixed bed. Regions of incipient motion are identified through local estimates of the Shields parameter exceeding the critical value. Potential areas of sediment deposition are identified with local estimates of the Rouse parameter exceeding ten. The model predictions of sediment response are in general in agreement with field observations of seabed morphology obtained over a one-week period during the 2003-2004 MVCO mine burial experiment. Both observations and simulations show potential transport occurring at the ends of the mine in wave-dominated events. Mean flows greater than 10 cm/s lead to the formation of larger scour pits upstream of the cylinder. Deposition in both cases tends to occur along the sides, near the center of mass of the mine. However, the fixed-bed assumption prohibits the prediction of full perimeter scour as is observed in nature. Predicted scour and burial regimes for a range of wave and mean-flow combinations are established.     

以GIS为平台的海岛资源环境信息系统

地理信息系统是一种应用范围很广，地理信息管理功能十分强大的计算机应用软件。这种软件的应用与发展目前也得到海岸带科技、管理人员的重视．我们尝试用MAPINFO建立了江苏海岛资源环境信息系统，实践证明了这一系统的实用性和先进水平。本文介绍了该系统的主要功能，并打算以此为基础建立海岸带资源环境信息系统，为江苏的“海上苏东”建设服务。     

Environmental problem solving in coastal ecosystems: A paradigm shift to sustainability

The human ecological footprint now extends to the entire globe, and human impacts are the dominant feature of many ecosystems, resulting in our current era being coined the ‘anthropocene’. This is particularly apparent in coastal ecosystems as human populations are increasing rapidly in coastal cities and the ecosystem services in these areas are rapidly being compromised. Science has historically progressed as a series of paradigm shifts and this paper reviews this history of paradigm shifts and makes the case that the next major paradigm shift will be directed at sustainability, resulting in a shift in scientific focus on solving rather than just studying our current environmental problems. Traditionally, science has been extremely effective at data acquisition and then successively less effective at translating this into information, knowledge and finally environmental problem solving. The currently required paradigm shift is to focus on environmental problem solving, filling gaps in knowledge, information and data only as required to solve a particular problem. A key element in turning this process around is better science communication between scientists, key stakeholders and the community. This will require more ‘science communicators’ who can use credibility, tenacity, creativity and virtue to effect solutions.     

THESEUS decision support system for coastal risk management

While planning coastal risk management strategies, coastal managers need to assess risk across a range of spatial and temporal scales. GIS-based tools are one efficient way to support them in the decision making process through a scenarios analysis starting from social, economic and environmental information integrated into a common platform. However, this integration process requires a significant effort from a team of scientists in terms of a) identifying the appropriate scales and data resolution for analysing social, environmental and economic issues; b) selecting and linking an appropriate set of tools to build a coupled model; c) representing key emerging (and hence challenging) research issues, such as risk perception and social resilience in the model; d) developing multi-criteria analysis to integrate social, environmental, economic impacts; and e) accounting for the expectations of the stakeholders and therefore optimizing the opportunity for them to interact with the tool development and with the final tool itself.In this spirit, this paper presents an open-source Spatial Decision Support System developed within the THESEUS Project to help decision makers to scopeg optimal strategies to minimise coastal risks. The exploratory tool allows the users to perform an integrated coastal risk assessment, to analyse the effects of different combinations of engineering, social, economic and ecologically based mitigation options, across short (2020s), medium (2050s) and long-term (2080s) scenarios, taking into account physical and non-physical drivers, such as climate change, subsidence, population and economic growth.     

Testing the application of the Systems Approach Framework (SAF) for the management of eutrophication in the Ria Formosa

The SAF (Systems Approach Framework) encompasses the ecological, social and economic components of coastal zones and aims to establish a permanent dialogue between scientists, stakeholders and policy makers working within European coastal zones for developing effective ICZM (Integrated Coastal Zone Management). The objective of the present study is to test the application of the SAF for defining eutrophication management options in the Ria Formosa, Portugal. Stakeholders were identified and the issue of eutrophication was agreed upon. Having defined the virtual system, the conceptual model of the Ria Formosa was developed. The formulation of the conceptual model into a mathematical model representing the ecological, social and economic components of the system is then discussed. The linking variable of the three components within the simulation model, as well as the scenarios to be run are then explored. The role of scientists as facilitators within the deliberation process is discussed, and a format by which the final output package could be disseminated is suggested. This case study demonstrates how the SAF could successfully be applied to the management of eutrophication in the Ria Formosa. It also suggests ways in which this approach may be adapted to address unique coastal systems with specific system characteristics.     

Who and what is to be involved in successful coastal zone management: a Thailand example

Successful coastal zone management (CZM) requires the participation of five sectors: local people, government authorities, non-governmental organizations (NGOs), scientists and investors. NGOs must play an important role in providing the opportunities for all sectors to meet and talk with each other. All the parties involved should have the chance to express and exchange their opinions. They should be able to discuss the problems they are facing and how they would like them to be solved. When all needs and problems have been discussed scientists or academics could then provide their expertise in formulating the CZM plan. The plan should reflect all the needs each sector has expressed as well as mitigation measures for implementation. Such- a co-management process should result in a satisfactory and sustainable CZM plan. This plan should be monitored and revised whenever it is seen fit. This is the pattern that Thailand is experiencing.