The aim of the book is to present for non-specialist researchers as well as for experts a comprehensive overview of the background, key ideas, basic methods, implementation details and a selection of solutions offered by a novel technology for the optimisation of the location of dangerous offshore activities in terms of environmental criteria, as developed in the course of the BalticWay project. The book consists of two parts. The first part introduces the basic principles of ocean modeling and depicts the long way from the generic principles to the practical modeling of oil spills and of the propagation of other adverse impacts. The second part focuses on the techniques for solving the inverse problem of the quantification of offshore areas with respect to their potential to serve as a source of environmental danger to vulnerable regions (such as spawning, nursing or also tourist areas). The chapters are written in a tutorial style; they are mostly self-contained and understandable for non-specialist researchers and students. They are carefully peer-reviewed by international experts. The goal was to produce a book that highlights all key steps, methods, models and data sets it is necessary to combine in order to produce a practically usable technology and/or decision support system for a particular sea region. Thus the book is useful not only as a description and a manual of this particular technology but also as a roadmap highlighting the complicated technical issues of ocean modeling for practical purposes. It describes the approaches taken by the authors in an understandable way and thus is useful for educational purposes, such as a course in industrially and environmentally relevant applications of ocean modeling.

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.

Thisvolumecontainsacollectionofpapersbyinternationalexpertsingeoph- ical ?uid dynamics, based upon presentations at a colloquium held in memory of Pedro Ripa on the ?rst anniversary of his untimely death. They review or present recent developments in hydrodynamic stability theory, Hamiltonian ?uid mechanics, balanceddynamics, waves, vortices, generaloceanographyand the physical oceanography of the Gulf ofCalifornia; all of them subjects in which Professor Ripamadeimportant contributions. His work, but also his friendly spiritandkindnesswerehighly regardedandappreciatedby colleagues and students alike around the world. This book is a tribute to his scienti?c legacy and constitutes a valuable reference for researchers and graduate s- dents interested in geophysical and general ?uid mechanics. Earlyin his career asa physicaloceanographer, Pedro Ripa made two la- mark contributions to geophysical ?uid dynamics. In 1981, he showed that the conservation of the potential vorticity is related to the invariance of the eq- tions of motion under the symmetry transformationsof the labels that identify the ?uid particles. That is, potential vorticity conservation is a consequence, via Noether's theorem, of the particle re-labelling symmetry. Two years later he published a paper entitled "General stability conditions for zonal ?ows in a one-layer model on the beta-plane or the sphere," where he established nec- sary conditions for stability in the shallow water equations, nowadays known as "Ripa's Theorem. " This is one of the very few Arnol'd-like stability con- tions that goes beyond two-dimensional or quasi-geostrophic ?ow, and stands alongside other famous stability criteria in making the foundations of the ?eld.

Although international scientific cooperation - particularly in meteorology - was established previous to the first International Polar Year, the IPY-1 (1882-83) is considered to be the first revolutionary step towards an extensive international cooperation in the polar areas for the benefit of science rather than national prestige and territorial gain. This was followed by IPY-2 (1932-33) and IPY-3 - actually the International Geophysical Year (1957-58) - before the crowning effort of IPY-4 (2007-08). The history of these years is recounted here and explains the political, economic, technical and scientific conditions and expectations that laid the basis for each IPY and which gradually expanded both the scope and extent of our understanding of the complexities in polar regions

Easter Island, a World Heritage Site is still, after over 50 years since Thor Heyerdahl's work on the island, a fascinating area to explore and learn about a culture that has only remnants remaining, while documenting a marine ecology still mostly unknown. Easter Island: Scientific Exploration into the World's Environmental Problems in Microcosm presents the research results from three years of interdisciplinary expeditions to Easter Island. The primary objectives were to investigate the effects of human population growth on the ecology of the island and to discover whether any dramatic climatic changes such as a prolonged El Nino could have disrupted the island's fragile ecosystem. The interdisciplinary scientific team were mainly researching the paleontology, archaeology, climatology, and geophysics of the island. This book now brings together the results of the three expeditions, identifies new areas of research, and hopefully will continue to inspire aspiring scientists to revisit this amazing island to explore and demystify this timeless enigma of human history.

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.

Research of the origins of life in connection with a marine environment started at the end of the seventies, when the black smokers' in the Pacific were discovered and the Red Sea deep hydrothermal brines were found to be a fruitful environment for abiotic synthesis of life precursors. For a while this research was categorised under the heading chemistry', but in less than a decade the topic became fully integrated into the science of 'oceanography'. The Scientific Committee on Oceanographic Research (SCOR) initiated Working Group 91: Chemical Evolution and Origin of Life in Marine Hydrothermal Systems'. This volume contains the final report of this working group.

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.

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).

This book presents a historical perspective on plate tectonics. In doing so it discusses the foundations of rigid plate tectonics and the limitations of this approach. This classic approach explains the data at a level of 95 % precision. The authors explain data anomalies as a result of the discrepancies between spatial geodetical data and rigid kinematics in oceans. Data and its interpretation from various disciplines are pulled together in this book.

This book is devoted to the quantitative physical modeling of subduction and subduction-related processes. It presents a coherent description of the modeling method (including similarity criteria, and a novel applied experimental technique), results from model experiments, theoretical analysis of results on the basis of continuum mechanics, and their geodynamic interpretation. Subduction is modeled in general as well as applied to particular regions using both 2-D and 3-D approaches, with both slab-push and slab-pull driving forces. The modeling covers all stages from subduction initiation to death', different regimes of subduction producing back arc extension and compression, blocking of subduction and jumps of subduction zone, arc-continent collision and continental subduction. This work is for geologists and geophysicists interested in geodynamics of the convergent plate boundaries and in mechanics of the lithosphere.

Marine protected areas (MPAs) have an important role in marine conserva tion programmes around the world. Although most have been established relatively recently when compared with protected areas on land, there is considerable expertise on their identification, setting up and management. Some techniques have been adapted from those used on land. Others are novel, and unique to marine conservation. The chapters in this book give an insight into this fast developing field where experiment and innovation work alongside techniques which have been tried and tested. The guiding princi ples behind key stages in the setting up and management of MP As are described, and case studies illustrate how they have worked. While it is most encouraging to read about the successes, the case studies also point to difficulties which have been encountered. Not all of the examples are new or recent but, together, they illustrate what is happening in this field.

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).

This book contains the most recent progress in data assimilation in meteorology, oceanography and hydrology including land surface. It spans both theoretical and applicative aspects with various methodologies such as variational, Kalman filter, ensemble, Monte Carlo and artificial intelligence methods. Besides data assimilation, other important topics are also covered including targeting observation, sensitivity analysis, and parameter estimation. The book will be useful to individual researchers as well as graduate students for a reference in the field of data assimilation.

This volume reflects the present state of the study of the Mediterranean as carried out by the Italian scientific community. The multidisciplinary character of the papers creates different "transversal" reading and clustering possibilities that the informed reader is free to design and undertake autonomously.

Experts in the field offer the first comprehensive review of the tectonics and magmatism of backarc basins, covering their initial rift stage to mature spreading. Complete with numerous illustrations, each of the twelve chapters focuses on a young, active backarc basin of the circum-Pacific-where volcano-tectonic processes are best studied because of their activity. Key themes in this volume include volcano-tectonics setting; cause and location; rift magmas; and hydrothermal activity. Researchers also present models of the dynamic processes occurring in backarc basins.

Solid-solution equilibria of marine evaporites are important in a wide range of science and technology. However, the data had not yet been summarized in a form that is at the same time comprehensive and permits to understand how the quinary seawater system builds up from its bounding systems. Thus the goal of the present volume is at the same time scientific and educational. The understanding of solid-solution equilibria of the various systems with respect to dissolution, precipitation and transformation of solids, their application to the evolution of brines, and a fast access to data is a necessary requirement for any modelling, especially in Geoscience. Another goal is to show the avail ability of data. Unfortunately, though solubility data are numereous there are substantial gaps, especially with respect to high temperatures. But also up to about 100 0 C data are missing for some of the systems so that they cannot be described entirely. Based on the present volume further work on the solubili ties of the minerals of marine evaporites may be promoted. The data have been viewed and collected over several years by the first author. The second author entered the preparation of the volume when it was realized that besides graphics and tables a fast access to data was required. Although both authors are responsible for the whole volume, responsibility is weighted somewhat differently for the various parts."

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.

Opening Speech of the ICEDIVE 84 Conference by His Royal Highness Prince Bertil of Sweden I am very pleased to be invited to open the International Conference ICEDIVE 84, dealing with medical and technical problems of diving and related underwater activities in arctic conditions. Until recent times, the arctic was considered astrange and remote area of minor importance. However, in a world with diminishing natural resources, arctic areas have become a region of global importance because of their enormous resources and strategie position. Certain experts believe that more than 50% of oil reserves are "sleeping" in these northern areas which are cold, harsh and hostile to man. Operations in arctic areas are extremely difficult, expensive, and demand high levels of technical, scientific and physiological achievement. One should recall for example, that Alaskan oil investment onIy became economically viable after the 1973-1974 price explosion. Recent political/military troubles in the Gulf have increased interest in the development of polar resources. This conference is unique as it is the first time that medical and technical specialists interested in the problem of diving in arctic conditions have met in an international forum. Development of the arctic resources is a matter of international urgency, and it pleases me that scientists from the USA, Canada, the USSR, Australia and Europe have gathered here in Stockholm to present their experience and to discuss problems in this field.

This book grew out of lectures on geophysical fluid dynamics delivered over many years at the Moscow Institute of Physics and Technology by the author (and, with regard to some parts of the book, by his colleagues). During these lectures the students were advised to read many books, and sometimes individual articles, in order to acquaint themselves with the necessary material, since there was no single book available which provided a sufficiently complete and systematic account (except, perhaps, the volumes on Hydrophysics of the Ocean, Hydrodynamics of the Ocean, and Geodynamics in the ten-volume Oceanology series published by Nauka Press in 1978-1979; these refer, however, specifically to the ocean, and anyway they are much too massive to be convenient for study by students). As far as we know, no text corresponding to our understanding of geophysical fluid dynamics has as yet been published outside the Soviet Union. The present book is designed to fill this gap. Since it is customary to write the preface after the entire book has been completed, the author has an opportunity there to raise some points of possible criticism by the reviewers and readers. First of all, note that this work presents the theoretical fundamentals of geophysical fluid dynamics, and that observational and experimental data (which in the natural sciences are always very copious) are referred to only rarely and briefly.

There is now an awareness within the industry, particularly as oil companies direct considerable resources towards developing diverless production systems, that a fully integrated approach to equipment design and intervention is necessary to achieve an acceptable system. The requirement for an integrated approach to equipment design and intervention is applicable not only to diverless depths but to all subsea structures, equipment and intervention techniques in whatever depth. Fortunately the inherent dexterity of the diver does not impact so severely on design as other intervention techniques. However the benefits of an integrated approach are still applicable and the use of such simple "diver aids" as cutting guides and subsea markings installed prior to the installation of jackets and subsea equipment can have a significant impact on the cost of intervention. This paper examines the requirements and limitations in designing subsea equipment for Remotely Operated Vehicle (ROV) intervention. For the oil company embarking on the development of a diverless production system, be it totally diverless because of the envisaged water depth or primarily diverless with the possibility of diver back up, the intervention techniques adopted will strongly influence the final system design. The necessity to undertake an extensive development programme to produce the optimum intervention system is very costly, requires long lead times and comprehensive testing particularly where novel solutions are adopted. It is a daunting prospect for even the most progressive of oil companies.

When, in 1966, the Gennan Research Society directed the attention of oceanographers in the Federal Republic of Ger many to problems of marine pollution, I was not enthusiastic. Emphasis on this problem area meant that other important research plans had to be postponed. But the lectures at the Third International Oceanographic Congress, September 1970, in Tokyo, and at the FAO Conference on Marine Pollution and its Effects on Living Resources and Fishing, December 1970, in Rome, convinced me that research on problems of marine pollution is a social obligation, and that the oceanographer has to take a stand. I issued public warnings about the continuing use of pesticides and had to defend myself against protests by the fishing industry and many colleagues who were, in Novem ber 1970, unaware of the extent of the threat. Thus, I was required by my profession to acquire an overview of the prob lems of ocean pollution. In 1971 I only needed to familiarize myself with some one hundred bibliographical items. In the interim, the flood of data has risen dramatically, and in the year 1975, no fewer than 868 publications under the heading of "Marine Pollution" were reported (Table 1). It is, therefore, more and more diffi cult to distinguish new results of scientific research from the many repetitions and variations, and I fear that from year to year my efforts to illustrate the actual status of the problem at a given moment will be subject to more gaps."

The monograph presented to foreign readers has been prepared by the famous Soviet investigators of processes of geochemistry and sedimentation in the Mediterranean Sea. For more than 20 years E.M. Emelyanov has examined the recent sedimentation of the Mediterranean Sea and K.M. Shimkus has studied the Quaternary and the earlier sedi mentation of the area. The authors, scientific workers from the P.P. Shirshov Institute of Oceanology, USSR Academy of Sciences (Atlantic and Southern Depart ments), took part not only in numerous cruises on oceanographic vessels of the USSR, but in the study of cores of the deep-sea drilling on R/V "Glomar Challenger." A great number of scientific papers and some books devoted to the processes of sedimentation and geochemistry of the Mediterranean Sea were written by them. Although the scientific interests of the authors are not only limited to these questions, I should like to emphasise these aspects of their scientific activity when introducing this book. The Mediterranean Sea is a suitable natural laboratory for solving a number of principal problems of marine sedimentation and lithogenesis."

The impetus for the conference held at Bombannes, France in May, 1982 arose out of a Scientific Committee on Oceanic Research (SCOR) Working Group on "Mathematical Models in Biological Oceanography." This group was chaired by K.H. Mann and held two meetings in 1977 and 1979. At both meetings it was felt that, although reductionist modelling of marine ecosystems had achieved some successes, the future progress lay in the development of holistic ecosystem models. The members of the group (K.H. Mann, T. Platt, J.M. Colebrook, D.F. Smith, M.J.R. Fasham, J. Field, G. Radach, R.E. Ulanowicz and F. Wulff) produced a critical review of reductionist and holistic models which was published by the Unesco Press (Platt, Mann and Ulanowicz, 1981). One of the conclusions of this review was that, whether holistic or reductionist models are preferred, it is critically important to increase the scientific effort in the measurement of physiological rates for the computation of ecological fluxes. The Working Group therefore recommended that an international meeting should be organized which would attempt to bring together theoretical ecologists and biological oceanographers to assess the present and future capability for measuring ecological fluxes and incorporating these data into models. An approach was made to the Marine Sciences Panel of the NATO Science Committee who expressed an interest in funding such a meeting. They awarded a planning grant and a planning group was formed consisting of M.J.R. Fasham, M.V. Angel, T. Platt, R.E.

Primary productivity in the sea accounts for 30% of the total global annual production. Holistic understanding of the factors determining marine productivity requires detailed knowl edge of algal physiology and of hydrodynamics. Traditionally studies of aquatic primary productivity have heen conducted hy workers in two major schools: experimental laboratory biology, and empirical field ecology. Here an attempt was made .to hring together people from both schools to share information and con cepts; each author was charged with reviewing his field of exoer tise. The scope of the Symposium is broad, which we feel is its strength. We gratefully acknowledge financial support from the Depart ment of Energy, the United States Environmental Protection Agency, the National Oceanic and Atmospheric Administration, including the NMFS Northeast Fisheries Center and the MESA New York Bight Project. Thanks are due to Mrs. Margaret Dienes, with out whose editorial skills this volume could not have been pro duced, and to Mrs. Helen Kondratuk as Symposium Coordinator. Finally, we wish to record our indebtedness to Dr. Alexander Hollaender for his tireless efforts and valuable advice in sup porting all aspects of this Symposium."