Oceanographic discontinuities (e. g. frontal systems, upwelling areas, ice edges) are often areas of enhanced biological productivity. Considerable research on the physics and biology of the physical boundaries defining these discontinues has been accomplished (see [I D. The interface between water and sediment is the largest physical boundary in the ocean, but has not received a proportionate degree of attention. The purpose of the Nato Advanced Research Workshop (ARW) was to focus on soft-sediment systems by identifying deficiencies in our knowledge of these systems and defining key issues in the management of coastal sedimentary habitats. Marine sediments play important roles in the marine ecosystem and the biosphere. They provide food and habitat for many marine organisms, some of which are commercially important. More importantly from a global perspective, marine sediments also provide "ecosystem goods and services" [2J. Organic matter from primary production in the water column and contaminants scavenged by particles accumulate in sediments where their fate is determined by sediment processes such as bioturbation and biogeochemical cycling. Nutrients are regenerated and contaminants degraded in sediments. Under some conditions, carbon accumulates in coastal and shelf sediments and may by removed from the carbon cycle for millions of years, having a potentially significant impact on global climate change. Sediments also protect coasts. The economic value of services provided by coastal areas has recently been estimated to be on the order of $12,568 9 10 y" [3J, far in excess of the global GNP.

The authors explain the rewarding results from the interdisciplinary collaboration between an environmental study group working on coastal ecosystems and effects of oil spills and applied mathematicians modelling wave motion on sandy beaches. By using the unified Navier-Stokes equations with a Bingham fluid model for spilled oil, multi-phase flow analysis were made. Decomposition of spilled oil by bacteria was simulated as a chemical reaction, and the theoretical and numerical analysis suggested a countermeasure to help reduce stress on coastal ecosystems. The new understanding of how ecosystems both depend upon, and help to determine, the nature of the shoreline demonstrates promising ways to better assist and exploit the regenerative powers inherent in nature.

Global warming, melting polar caps, rising sea levels and intensifying wave-current action, factors responsible for the alarming phenomena of coastal erosion on the one hand and adverse environmental impacts and the high cost of 'hard' protection schemes, on the other, have created interest in the detailed examination of the potential and range of applicability of the emerging and promising category of 'soft' shore protection methods. 'Soft' methods such as beach nourishment, submerged breakwaters, artificial reefs, gravity drain systems, floating breakwaters, plantations of hydrophylous shrubs or even dry branches, applied mostly during the past 20 years, are recognised as possessing technical, environmental and financial advantageous properties deserving more attention and further developmental experimentation than has occured hitherto. On the other hand, 'hard' shore protection methods such as seawalls, groins and detached breakwaters, artefacts borrowed from port design and construction technology, no matter how well designed and well implemented they may be, can hardly avoid intensification of the consequential erosive, often devastating, effects on the down-drift shores. Moreover, they often do not constitute environmentally and financially attractive solutions for long stretches of eroding shoreline. Engineers and scientists practising design and implementation of shore defence schemes have been aware for many years of the public demand for improved shore protection technologies. They are encouraging efforts that promise enrichment of those environmentally sound and financially attractive methods that can be safely applied.

High Performance Computing in the Geosciences surveys the state of the art of programs presently being developed which require high performance computing for their implementation, provides a guide for decision making in regard to computing directions in future numerical models, and provides an overview of future developments in massively parallel processing and their implications for numerical modelling in the geosciences.

In the framework of the Diderot Mathematical Forum (DMF) of the European Mathematical Society (EMS), December 19-20, 1997, a Videoconference was held linking three teams of specialists in Amsterdam, Madrid and Venice respectively. The general subject of this videoconference, the second one of the DMF series, was Mathematics and Environment and more specifically, Problems related to Water.

This volume contains the texts of the Madrid site contributions with important, new and unpublished, examples on the modeling, mathematical and numerical analysis and treatment of the associated control problems of relevant questions arising in Oceanography and Environment.

To place this book in perspective it is useful for the reader to be aware of the recent history of the topic of underwater sound generation at the ocean surface by natural mechanisms. A meeting in Lerici, Italy in 1987 was convened within the NATO Advanced Research Workshop series, to bring together underwater acousticians and ocean hydrodynamicists to examine various mechanisms which generate sound naturally at the ocean surface. A record of that meeting was published in the NATO scientific publication series in 1988 under the title 'Sea Surface Sound'. That meeting was successful in inspiring and co ordinating both participants and non-attending colleagues to examine some key issues which were raised during the course of presentations and discussions. The understanding among those present was that another meeting should be convened 3 years hence to report and review progress in the subject. Accordingly the second conference was convened in Cambridge in 1990, whose proceedings are presented here. This volume represents a very gratifying increase in only a 3 year interval in our understanding of a number of physical processes which generate sound at the peripheries of oceans. In fact it represents both the acceleration of singular effort as well as the development of interdisciplinary sophistication and co-operation. The enthusiasm, goodwill, and intense scientific curiosity which characterized the Lerici meeting carried through to Cambridge. The collegial atmosphere established by the participants was perfectly timed to foster another major advance in studies of ocean surface sound.

Studies of convection in geophysical flows constitute an advanced and rapidly developing area of research that is relevant to problems of the natural environment. During the last decade, significant progress has been achieved in the field as a result of both experimental studies and numerical modelling. This led to the principal revision of the widely held view on buoyancy-driven turbulent flows comprising an organised mean component with superimposed chaotic turbulence. An intermediate type of motion, represented by coherent structures, has been found to play a key role in geophysical boundary layers and in larger scale atmospheric and hydrospheric circulations driven by buoyant forcing. New aspects of the interaction between convective motions and rotation have recently been discovered and investigated. Extensive experimental data have also been collected on the role of convection in cloud dynamics and microphysics. New theoretical concepts and approaches have been outlined regarding scaling and parameterization of physical processes in buoyancy-driven geophysical flows. The book summarizes interdisciplinary studies of buoyancy effects in different media (atmosphere and hydrosphere) over a wide range of scales (small scale phenomena in unstably stratified and convectively mixed layers to deep convection in the atmosphere and ocean), by different research methods (field measurements, laboratory simulations, numerical modelling), and within a variety of application areas (dispersion of pollutants, weather forecasting, hazardous phenomena associated with buoyant forcing).

Acoustic Signal Processing for Ocean Explortion has two major goals: (i) to present signal processing algorithms that take into account the models of acoustic propagation in the ocean and; (ii) to give a perspective of the broad set of techniques, problems, and applications arising in ocean exploration. The book discusses related issues and problems focused in model based acoustic signal processing methods. Besides addressing the problem of the propagation of acoustics in the ocean, it presents relevant acoustic signal processing methods like matched field processing, array processing, and localization and detection techniques. These more traditional contexts are herein enlarged to include imaging and mapping, and new signal representation models like time/frequency and wavelet transforms. Several applied aspects of these topics, such as the application of acoustics to fisheries, sea floor swath mapping by swath bathymetry and side scan sonar, autonomous underwater vehicles and communications in underwater are also considered.

This collection of 52 papers presents the state-of-the-art of Oceanology of China Seas, including Yellow Sea, East China Sea and South China Sea. The papers are published in two volumes comprising six parts: Volume 1: Physical Oceanography, Marine Chemistry and Marine Biology. Volume 2: Marine Geology, Coastal Research and Marine Physics and Technology. The purpose of this book is to introduce to the world the most representative research of Chinese oceanographers and provide marine developers with a significant reference work. For marine scientists and developers at oceanographic institutions, academia and naval research establishments. It will also be of value to the oil company geologist having an interest in the exploration of China Seas.

This volume is one outcome of the 6th International Conference on Paleoceano graphy (ICP VI). The conference was held August 23-28, 1998 in Lisbon, Portugal. The meeting followed the traditional format of a small number of invited oral presentations complemented by a large number ofcontributed posters. Over 550 participants attended, representing thirty countries and nearly 450 posters were presented. The invited speakers addressed the main themes of the 5oral sessions. The session topics were: Polar-Tropical and Interhemisphere Linkages; Does the Ocean Cause, or Respond to, Abrupt Climatic Changes?; Biotic Responses to Major Paleoceanographic Changes; Past Warm Climates; and Innovations In Monitoring Ocean History. This is the first time in ICP history that the Conference Proceedings are published. The aim of the organisers with the publication of this book is two-fold: to provide a useful review of the field and to document the ideas/controversies raised during the con ference that may stimulate future work. The book reflects the initial intentions of the conference, but it is not a conven tional conference proceedings, given that the papers have been reviewed by formal exter nal referees. Each of the conference topics is introduced by a review article designed to summarize the state of the art in each theme followed by articles prepared by the invited speakers. As with most conference proceedings, each theme is covered heterogenously. Some topics have all the expected contributions, others are less well covered."

The Fourteenth International Tsunami Symposium held from 31 July to 3 August 1989 in Novosibirsk, U.S.S.R., was sponsored by the International Union of Geodesy and Geophysics. Sixty-five scientists from 13 countries met to exchange information on recent advances in tsunami research. The Symposium was a great success due to the enthusiasm of the participants, the quality of research presented, and the great organization provided by the Soviet hosts. Teams of dedicated workers, under the fine leadership of Academician A. S. Alexseev and Dr V. K. Gusiakov, blended social and scientific activities in a memorable fashion. The 62 presentations of the Symposium were divided into six areas of research: generation (7), propagation (12), coastal effects (10), observations (11), seismics and tectonics (10), and hazard mitigation (12). A summary of the research presented appears as the first article in this special issue. Following the Symposium, a team of session chairmen nominated 20 of these oral presentations to be published in a special issue devoted to the International Tsunami Symposium.

The future of the Common Fisheries Policy depends on progress in the relevant areas of research. This applies to the whole range of management decisions, where precise, reliable and complete data are essential to inform those who must decide on the pursuit of existing activities, especially in the area of maritime fisheries, and the development of promising new activities such as aquaculture. Every day the Director-General of DG XIV requires more and more information to prepare decisions which will affect the future of all those in the Community who are dependent on fishing and aquaculture. There is thus a high level of direct demand from DG XIV. Over and above this immediate and specific requirement for short- and medium-term applications, research affects the competitivity of the Community. This is one area which favours the collaboration across frontiers of all those who seek to advance knowledge. But although DG XIV is uniquely placed to appreciate the importance of research into fisheries and aquaculture, there is no question of succumbing to the temptation to directly control the scope of research or its conduct. The notion of subsidiarity can best be understood by examining the existing structures in the Member States. The Commission must act first and foremost as a catalyst, by promoting the circulation of information and the coordination of research programmes.

Challenging problems involvrllg jet and plume phenomena are common to many areas of fundamental and applied scientific research, and an understanding of plume and jet behaviour is essential in many geophysical and industrial contexts. For example, in the field of meteorology, where pollutant dispersal takes place by means of atmospheric jets and plumes formed either naturally under conditions of convectively-driven flow in the atmospheric boundary layer, or anthropogenically by the release of pollutants from tall chimneys. In other fields of geophysics, buoyant plumes and jets are known to play important roles in oceanic mixing processes, both at the relatively large scale (as in deep water formation by convective sinking) and at the relatively small scale (as with plume formation beneath ice leads, for example). In the industrial context, the performances of many engineering systems are determined primarily by the behaviour of buoyant plumes and jets. For example, (i) in sea outfalls, where either sewage or thermal effluents are discharged into marine and/or freshwater environments, (ii) in solar ponds, where buoyant jets are released under density interfaces, (iii) in buildings, where thermally-generated plumes affect the air quality and ventilation properties of architectural environments, (iv) in rotating machinery where fluid jet~ are used for cooling purposes, and (v) in long road and rail tunnels, where safety and ventilation prcedures rely upon an understanding of the behaviour of buoyant jets. In many other engineering and oceanographic contexts, the properties of jets and plumes are of great importance.

This Brief deals with the reconstruction of Holocene paleoenvironment in the central part of Bangladesh in relation to relative sea-level (RSL) changes which is 200 km north from the present coastline. Lithofacies characteristics, mangal peat, diatom and paleophysiographical evidences were considered to reconstruct the past position and C-14 ages were used to determine the time of formation of the relative sea-level during the Holocene. With standard reference datum the required m.s.l. at the surface of five sections are calculate and the RSL curve suggests that Bangladesh has experienced two mid Holocene RSL transgressions punctuated by regressions. The abundant marine diatom and mangrove pollens indicates that the highest RSL transgression in Bangladesh is around 6000 cal BP which is attained at least 4.5 to 5m higher than the modern m.s.l. After this phase, the relative sea-level started to fall and consequently a freshwater peat developed around 5980 5700 cal BP. The abundant mangrove pollens in salt-marsh succession shows the regression around 5500 cal BP and, the height was 1 2 m higher than the modern sea level. These and more interesting findings are discussed in this Brief.

In Chapter 1 the methodological principles of systemization and visualization of multidimensional ecological information for its operational dissemination among potential users are stated. Their realization results in creation of the geographic-and ecologic model of marine basin as an information base for diagnosis of the marine ecosystem state, estimation of consequences of economic activity, and modelling of its changes with the use of mathematical tools. In Chapter 2 the geographic-and-ecological aspects of mathematical modelling of marine ecosystems, the possibilities and peculiarities of the most adequate models, the Russian hydrodynamic model of oil spills "SPILLMOD" and hydroecological model of organogenic compound transformation in the sea, are investigated. In the following six Chapters the examples of practical realization of geographic-and-ecological (as information source) and mathematical (as computing apparatus) modelling at the investigations of specific ecological problems associated with consequences of natural hazards and economic activity on aquatory and within the whole Black Sea basin are given.

"

Accretionary prisms in convergent margins are natural laboratories for exploring initial orogenic processes and mountain building episodes. They are also an important component of continental growth both vertically and laterally. Accretionary prisms are seismically highly active and their internal deformation via megathrusting and out-of-sequence faulting are a big concern for earthquake and tsunami damage in many coastal cities around the Pacific Rim. The geometries and structures of modern accretionary prisms have been well imaged seismically and through deep drilling projects of the Ocean Drilling Program (and recently IODP) during the last 15 years. Better understanding of the spatial distribution and temporal progression of accretionary prism deformation, structural and hydrologic evolution of the decollement zone (tectonic interface between the subducting slab and the upper plate), chemical gradients and fluid flow paths within accretionary prisms, contrasting stratigraphic and deformational framework along-strike in accretionary prisms, and the distribution and ecosystems of biological communities in accretionary prism settings is most important in interpreting the evolution of ancient complex sedimentary terrains and orogenic belts in terms of subduction-related processes. This book is a collection of interdisciplinary papers documenting the geological, geophysical, geochemical, and paleontological features of modern accretionay prisms and trenches in the northwestern Pacific Ocean, based on many submersible dive cruises, ODP drilling projects, and geophysical surveys during the last 10 years. It also includes several papers presenting the results of systematic integrated studies of recent to ancient on-land accretionary prisms in comparison to modern analogues. The individual chapters are data and image rich, providing a major resource of information and knowledge from these critical components of convergent margins for researchers, faculty members, and graduate and undergraduate students. As such, the book will be a major and unique contribution in the broad fields of global tectonics, geodynamics, marine geology and geophysics, and structural geology and sedimentology.

The goals ofthe Symposium were to highlight advances in modelling ofatmosphere and ocean dynamics, to provide a forum where atmosphere and ocean scientists could present their latest research results and learn ofprogress and promising ideas in these allied disciplines; to facilitate interaction between theory and applications in atmosphere/ocean dynamics. These goals were seen to be especially important in view ofcurrent efforts to model climate requiring models which include interaction between atmosphere, ocean and land influences. Participants were delighted with the diversity ofthe scientific programme; the opportunity to meet fellow scientists from the other discipline (either atmosphere or ocean) with whom they do not normally interact through their own discipline; the opportunity to meet scientists from many countries other than their own; the opportunity to hear significant presentations (50 minutes) from the keynote speakers on a range ofrelevant topics. Certainly the goal ofcreating a forum for exchange between atmosphere and ocean scientists who need to input to create realistic models for climate prediction was achieved by the Symposium and this goal will hopefully be further advanced by the publication ofthese Proceedings.

The Antarctic fish fauna has evolved over a long period of geographic and climatic isolation. In the course of this evolution, Antarctic fish have developed specialized adaptations, some of which characterize these organisms as unique. In strong contrast to the continental shelf faunas elsewhere, the Antarctic shelf ichthyofauna is dominated by a single highly endemic group, the Notothenioidei. This group of perciform fish probably first appeared and diversified in the early Tertiary. The development of the Polar Front (referred to as the Antarctic Convergence in the older literature) resulted in a natural oceanographic barrier to migration in either direction, and thus became a key factor in the evolution of Antarctic fish. The dominance of the Antarctic continental shelf fauna by a single taxonomic group of fish provides a simplified natural laboratory for exploring the wealth of physiological, biochemical and ecological adaptations that characterize the fauna. Understanding of the patterns of adaptation in this highly specialized group of fish can tell us much about of evolution.

Anoxic basins are ofgreat interest to oceanographersofall disciplines. Theirextreme conditionsresult from acombinationofhigh oxygen utilization and restricted circulation. It is necessery to understand present -day anoxic environments ifwe are to understand the early evolution of the oceans (e.g. SiIlen, 1965). Sarmiento et al.(1988a) explored the causes of anoxia in the global ocean, which is in effect a "closed" basin and in marginal seas such as the Eastern Mediterranean (Sarmiento et al. 1988b). Anoxic conditions have been proposed toexist in various ocean basins at different times in the geological past (e.g. the Crataceous period; Weissert, 1981) and possibly as recent as the last glacial maximum (e.g., Sarmiento and Toggweiler,1984). The modern Black Sea has been considered as the type anoxic basin. It is the world's 2 3 largest permanaently anoxic basin (area = 423,000 km; volume = 534,000 km ) and is thought to be aquasi-steady state system. It is extremely isolated from the rest ofthe world's oceans. Only the narrow and shallow Bosporus Strait provides water exchange with the Mediterranean. Concentrationsofhydrogen sulfide reach valuesof350 Mm in the deep water and the oxygen-hydrogen sulfide Interface exists between 80 and 200m waterdepth. The hydrographic regime is characterized by low salinity surface water of riverine origin overlying high salinity deep waterofMediterranean origin. Asteep pycnocline is the primary phycical barrier to mixing and is the origin of the stability of the anoxic interface.

In recent years, research on acoustic remote sensing of the ocean has evolved considerably, especially in studying complex physical and biological processes in shallow water environments. To review the state of the art, an international workshop was held at Carvoeiro, Portugal, in March 1999, bringing together leading international researchers in the field. In contrast to much of the recent theoretical work, emphasis was placed on the experimental validation of the techniques. This volume, based on presentations at this workshop, summarizes a range of diverse and innovative applications. The invited contributions explore the use of acoustics to measure bottom properties and morphology, as well as to probe buried objects within the sediment. Within the water column, sound is applied to imaging of oceanographic features such as currents and tides or monitoring of marine life. Another key theme is the use of sound to solve geometric inverse problems for precise tracking of undersea vehicles. Audience: This volume should be useful both to the novice seeking an introduction to the field and to advanced researchers interested in the latest developments in acoustic sensing of the ocean environment. The workshop was sponsored by the Fundacao para a Ciecia e a Tecnologia (Portuguese Foundation for Science and Technology).

Curtis Ebbesmeyer is no ordinary scientist. He's been a consulting oceanographer for multinational firms and a lead scientist on international research expeditions, but he's never held a conventional academic appointment. He seized the world's imagination as no ordinary scientist could when he and his worldwide network of beachcomber volunteers traced the ocean's currents using thousands of sneakers and plastic bath toys spilled from storm-tossed freighters. Now, for the first time, Ebbesmeyer tells the story of his lifelong struggle to solve the sea's mysteries, and shares his most surprising discoveries. He recounts how flotsam has changed the course of history-leading Viking mariners to safe harbours, Columbus to the New World, and Japan to open up to the West - and how it may even have made the origin of life possible. He explores the vast floating garbage patches and waste-heaped junk beaches that collect the flotsam and jetsam of industrial society. Finally, he reveals the music-like mathematical order in oceanic gyres and the threats that global warming and disintegrating plastic waste pose to the seas ...and to us.

This authoritative guide enables accurate identification of the common components of the inshore benthic invertebrates of the British Isles and adjacent European coasts, as well as a substantial proportion of fish species. This new edition builds upon the strengths of the earlier work and is thoroughly revised throughout to incorporate advances in both the taxonomy and ecology of the organisms concerned.

Seafloor investigation has long been a feature of not only seismology but also of acoustics. Indeed it was acoustics that produced depth sounders, giving us the first capability of producing both global and local maps of the seafloor. Subsequently, better instrumentation and techniques led to a clearer, more quantitative picture of the seabed itself, which stimulated new hypotheses such as seafloor spreading through the availability of more reliable data on sediment thickness over ocean basins and other bottom features. Geologists and geophysicists have used both acoustic and seismic methods to study the seabed by considering the propagation of signals arising from both natural seismic events and man-made impulsive sources. Although significant advances have been made in instrumentation, such as long towed geophysical arrays, ai r guns and ocean bot tom seismometers, the pic ture of the seafloor is still far from complete. Underwater acoustics concerns itself today with the phenomena of propagation and noise at frequencies and ranges that require an understanding of acoustic interaction at both of its boundaries, the sea surface and seafloor, over depths ranging from tens to thousands of meters. Much of the earlier higher frequency (>1 kHz) work included the characterization of the seafloor in regimes of reflection coefficients which were empirically derived from surveys. The results of these studies met with only limited success, confined as they were to those areas where survey data existed and lacking a physical understanding of the processes of reflection and scattering.

Did you know that the Grand Bank earthquake of 1929 triggered a huge submarine mass movement which broke submarine cables over a distance of up to 1000 km from its source and generated a tsunami which devastated a small village in Newfoundland killing 27 people? The same happened in Papua New Guinea in 1998 with more than 2000 casualties. Submarine mass movements of various sizes and styles are shaping the sea floor and are of concern for many facets of human activities both onshore and offshore. These include the development of natural resources, energy and communication transport, coastal infrastructures and communities. This book provides a world-wide perspective of submarine mass movements and their consequences. This has been made possible by assembling excellent contributions from active researchers, groups, or institutions, thus providing full coverage of the many scientific and engineering aspects of this type of marine and coastal geo-hazard. It covers fundamental as well as site specific studies from many areas including the Atlantic and Pacific oceans, inner seas like the Mediterranean Sea, and fjords using the most recent technologies from multibeam sonar imaging techniques, 3D seismic analysis, slope stability analysis, to debris flow and tsunami modeling.

Audience: This book is of interest to any researcher in the field of marine and coastal geo-hazards. It will be useful for planners, scientists and engineers involved in the development of offshore and near-shore resources and also to those in charge of the management and mitigation of coastal hazards. For graduate students, this book provides an up-to-date vision of the process of submarine mass movements and their consequences from both a scientific and an engineering standpoint, and it includes a unique collection of the existing literature on marine geo-hazards.

CD-Rom included
This volume contains a CD-Rom which in addition to an electronically searchable version of the contributions, has full colour versions of figures which are printed in black and white in the book.