The fonner Egyptian Minister of State for Foreign Affairs and fonner UN Secre tary General, Butros Butros Ghali stated after the second Gulf War "The next war in the Middle East will not be fought for oil, but for water. " This famous statement has been echoed by many politicians: shortly before be coming president of Turkey, SOleyman Demirel declared that the waters of the Euphrates and Tigris belonged to Turkey, just as oil belongs to the Arabs. Rafael Eytan, at that time and now again Israeli Minister of Agriculture, declared in 1990 in full-page advertisements in the Jerusalem Post that Israel would never cede the West Bank to the Palestinians because Israel's water supply would otherwise be endangered. Finally, Ismail Serageldin, vice president of the World Bank, declared in 1995 that "the wars of the next century will be over water." These statements are typical of the atmosphere reigning in the Middle East and in several other places around the world concerning the issue of international fresh water resources. Whether these perceptions correspond to an actual threat to a nation's water supply or whether they correspond to the official position of states in negotiations often conducted secretly, is an entirely different matter. A closer analysis of the issue of international fresh water resources, as we attempt in this book, admittedly reveals a dangerous potential for conflict over water."

Floods constitute a persistent and serious problem throughout the United States and many other parts of the world. They are responsible for losses amounting to billions of dollars and scores of deaths annually. Virtually all parts of the nation--coastal, moun tainous and rural--are affected by them. Two aspects of the problem of flooding that have long been topics of scientific inquiry are flood frequency and risk analyses. Many new, even improved, tech niques have recently been developed for performing these analyses. Nevertheless, actual experience points out that the frequency of say a 100-year flood, in lieu of being encountered on the average once in one hundred years, may be as little as once in 25 years. It is there fore appropriate to pause and ask where we are, where we are going and where we ought to be going with regard to the technology of flood frequency and risk analyses. One way to address these questions is to provide a forum where people from all quarters of the world can assemble, discuss and share their experience and expertise pertaining to flood frequency and risk analyses. This is what constituted the motivation for organizing the International Symposium on Flood Frequency and Risk Analyses held May 14-17, 1986, at Louisiana State University, Baton Rouge, Louisiana.

Nowadays, major environmental issues are the object of large public debates de- spite the fact that scientific knowledge is often insufficient to draw unequivocal conclusions. Such is the case in the ongoing debate regarding the specific contri- butions of anthropogenic greenhouse gas emissions and of natural climate changes to global warming. At least 10 to 20 years of additional observations will be re- quired, before we will be able to conclude, with certainty, on this subject. In the mean time, and as directed by their immediate interests, people will continue to promote contradictory opinions. The media are, in part, responsible for perpetuat- ing such debates in that they convey indiscriminately the opinion of highly credi- ble scientists as that of dogmatic researchers, the latter, unfortunately too often expressing working hypotheses as established facts. Naturally, in a similarly mis- informed manner, pressure groups tend to support the researcher whose opinions most closely represent either their particular ideological battles or their economic interests and, hence, in their own way, add further to the confusion and obscurity of the debate. Only a few years ago, mercury (Hg)contamination in hydroelectric reservoirs was the object of such media and social biases. At the time, analytical data used to support the discourse were themselves uncertain and numerous hypotheses, often times fanciful, were proposed and hastily "delivered" to the public.

Water is one of the world's threatened resources: it is also a substance of importance in Geology. For some years I have felt the need for a book that sets out the fundamentals of fluid mechanics, written for geologists rather than engineers. The efforts to repair my own deficiencies in this respect led me along various unfamiliar paths, few of which were unrewarding. This book is the result of my journeys through the literature and as a geologist in several parts of the world. It has been written for students of geology of all ages, in the simplest terms possible, and it has one objective: to provide a basis for an understanding of the mechanical role of water in geology. It has not been written for experts in ground water hydrology, or specialists in the fluid aspects of structural geology: it has been written for geologists like me who are not very good mathematicians, so that we can take water better into account in our normal geological work, whatever it might be. The fundamentals apply equally to mineralization, geochemistry, and vulcanology although they have not been specifically mentioned. It has also been written for the university student of geology so that he or she may start a career with some appreciation of the importance of water, and understanding of its movement."

In recent years, much concern has been expressed on the deleterious effects that anthropogenic emissions of acidic pollutants have on ecosystems of both industrialized countries and remote areas of the world. In many of these regions, seasonal snowcover is a major factor in the transfer of atmospheric pollutants, either to terrestrial and aquatic ecosystems or to the more permanent reservoirs of glaciers and ice sheets. The recognition of the role that seasonal snowcovers can thus play in the chemical dynamics of whole ecosystems was recently echoed by the Committee on Glaciology of the National Research Council (National Academy of Sciences, National Academy of Engineering and the Institute of Medicine) which recommended that studies on "Impurities in the snowpack, their discharge into runoff, and management of the problem" be rated at the highest prority level (ref. a). It is in this context that the Advanced Research Institute (ASI) brought together scientists active in the fields of snow physics, snow chemistry and snow hydrology. The programme was structured so as to facilitate the exchange of information and ideas on the theories for the chemical evolution of seasonal snowcovers and snowmelt and on the impact of the chemical composition of the meltwaters on the different components of hydrological systems. As a consequence the ASI also attracted participants from potential users of the information that was disseminated; these were particularly concerned with the effects of snowmelt and snowcover on terrestrial biota and those of lakes and streams.

Floods constitute a persistent and serious problem throughout the United States and many other parts of the world. They are responsible for losses amounting to billions of dollars and scores of deaths annually. Virtually all parts of the nation--coastal, moun tainous and rural--are affected by them. Two aspects of the problem of flooding that have long been topics of scientific inquiry are flood frequency and risk analyses. Many new, even improved, tech niques have recently been developed for performing these analyses. Nevertheless, actual experience points out that the frequency of say a IOO-year flood, in lieu of being encountered on the average once in one hundred years, may be as little as once in 25 years. It is therefore appropriate to pause and ask where we are, where we are going and where we ought to be going with regard to the technology of flood frequency and risk analyses. One way to address these ques tions is to provide a forum where people from all quarters of the world can assemble, discuss and share their experience and expertise pertaining to flood frequency and risk analyses. This is what con stituted the motivation for organizing the International Symposium on Flood Frequency and Risk Analyses held May 14-17, 1986, at Louisiana State Universj. ty, Baton Rouge, Louisiana."

Proceedings of the NATO Advanced Study Institute, Aussois, France, September 4-15, 1985

This book covers topics on the basic models, assessments, and techniques to calculate evapotranspiration (ET) for practical applications in agriculture, forestry, and urban science. This simple and thorough guide provides the information and techniques necessary to develop, manage, interpret, and apply evapotranspiration ET data to practical applications. The simplicity of the contents assists technicians in developing ET data for effective water management.

In this book major construction projects are reviewed. The aim is to present case studies or topics which would stimulate discussion within the areas of environmental policy, economy, ethics or science. By carefully balancing the needs and interests of all involved stakeholders and by observing basic ethical principles, it is possible to resolve the conflicts and to proceed towards constructive cooperation with commonly accepted environmental objectives. The book further contains the key conclusions and recommendations resulting from the "First International Symposium on Large-Scale Constructions in Coastal Environments" held on the island of Norderney from 21-25 April 1997.

This volume is the result of an initiative of the Commission on the Coastal Environment of the International Geographical Union. The initial concept from which the plan has proceeded was presented at the 24th International Geographical Congress in Japan in 1980. AUTHORSHIP AND COVERAGE All of the articles in this volume have been written by specialists familiar with the coastal segment discussed. Nearly all have been prepared by citizens of the country (and, for that matter, even each subregion) considered. In the case of exceptions (e.g. Suriname), the authors have conducted fieldwork on the coast of the country they treat. In order to preserve the "on-the-spot" integrity of the volume, it was decided not to fill in the blanks along the world's coastline with library researched chapters. Thus, coverage is variable. Nearly every coastal country in Europe is represented whereas for Africa and South America there are major gaps. In addition, there are 2 instances of overlap. In the case of England (with a shoreline of nearly 3,000 km) a complementary chapter on Lincolnshire (with a shoreline of only 155 km) is included. The other case is the general article on the Baltic Coast of the USSR which is supported by chapters on Estonia and Lithuania.

Remote sensing is the study of a region from a distance, particularly from an airplane or a spacecraft. It is a tool that can be used in conjunction with other methods of research and investigation. This tool is especially applicable to the study of the deserts and arid lands of the Earth because of their immense size and their inaccessibility to detailed study by conventional means. In this book examples are given of the utility of aerial photographs and space images in the study of semi-arid, arid, and hyper-arid terrains. Emphasis is placed on the physical features and terrain types using examples from around the world. The authors I have called upon to prepare each chapter are renowned specialists whose contributions have received international recognition. To the general reader, this book is a review of our knowledge of the relatively dry parts of the Earth, their classification and varied features, their evolution in space and time, and their development potentials. To the specialist, it is a detailed account of the deserts and arid lands, not only in North America, but also their relatively unknown counterparts in North Africa, Australia, China, India, and Arabia.

This book provides a state-of-the-art overview of the development of concepts and methodology of hydrological sys tems analysis and its wide range of practical applications. Hydrological systems analysis involves the management, processing and interpretation of huge amounts of geoscien tific as well as ecological and historical data of many different types and sources, which can only be handled coherently and efficiently by using interactive geoscientific information systems. Geoscientific information systems as well as flow simulators are integral parts of the methodology. The methodology is clearly explained in the book and ample figures il lustrate the text. The emphasis of the book is on the practical applicability of hydrological systems analysis in integrated water re source management, nature conservation and environmental planning. The compilation of many case-studies, conducted by TNO geohydrologists and others in recent years, included in the book deals with different temporal and spatial scales and various geohydrological settings in The Netherlands, Poland, the European Union as well as in Indonesia. These case studies underpin the strength and elegance of hydrological systems analysis."

The problem of ice destruction comes most frequently to our attention in engineering glaciology and ice engineering because it is essential in the solution of many problems in the polar regions of the Earth. Ice destruction (like the destruction of any other material, in principle) is a complex problem at the junction of solid-state physics, continuum mechanics, and materials science. Ice, particularly sea ice, is characterized by known anomalies that can be explained by the simultaneous occurrence of solid, liquid and gaseous phases. Even minor temperature fluctuations cause changes in the relationship of these phases and, as a consequence, change the physico-mechanical properties of ice. New hydraulic engineering tasks, associated with the destruction of such a complex material, demand continuous improvement of methods and techniques. The present authors have brought these together in a form which is convenient for a wide range of users. This book covers only local ice destruction, by means other than icebreakers, requiring comparatively low consumption of power in proportion to the volume and mass of destroyed ice. Problems of natural ice destruction under the influence of solar radiation, tidal, wind and wave factors are not dis cussed. Mechanical and thermal methods were the first of many to be used for ice destruction. Their application has involved a greater num ber of techniques, so the first two chapters are the longest."

Proceedings of the NATO Advanced Research Workshop on Advances in Analytical and Numerical Groundwater Flow and Quality Modelling, Lisbon, Portugal, June 2-6, 1987

On May 27-31, 1985, a series of symposia was held at The University of Western Ontario, London, Canada, to celebrate the 70th birthday of Pro fessor V. M. Joshi. These symposia were chosen to reflect Professor Joshi's research interests as well as areas of expertise in statistical science among faculty in the Departments of Statistical and Actuarial Sciences, Economics, Epidemiology and Biostatistics, and Philosophy. From these symposia, the six volumes which comprise the "Joshi Festschrift" have arisen. The 117 articles in this work reflect the broad interests and high quality of research of those who attended our conference. We would like to thank alI of the contributors for their superb cooperation in helping us to complete this project. Our deepest gratitude must go to the three people who have spent so much of their time in the past year typing these volumes: Jackie BeU, Lise Constant, and Sandy Tamowski. This work has been printed from "camera ready" copy produced by our Vax 785 computer and QMS Lasergraphix printers, using the text processing software TEX. At the initiation of this project, we were neophytes in the use of this system. Thank you, J ackie, Lise, and Sandy, for having the persistence and dedication needed to complete this undertaking."

The idea for this volume came during the dryland sessions of the Association of American Geographers meeting in San Diego in April, 1992. The large number of papers devoted to aeolian processes and landforms indicated to me that aeolian geomorphology had come of age and the last 15 years or so had produced a plethora of papers, books, and edited volumes on all aspects of aeolian geomorphology. Chapter one is my tentative attempt to place develop ments in aeolian geomorphology in a historical perspective and to contemplate some thoughts about the future. The fourteen papers selected address a wide range of issues ranging from micro-scale studies devoted to aeolian dust, sediment transport, and rock varnish in ventifacts to medium-scale studies of dunes and dune forms, reverse desertification, and macro-scale studies of ergs and sand transport pathways. The American Southwest, particularly the spectacular and unique Mojave Desert of California, is featured prominently in seven chapters. I hope this volume provides students and colleagues some new perspectives in aeolian geomorphology as well as pathways for future work."

Soil science is perhaps one of the oldest practical sciences, having been of concern to man probably from the time he progressed from a strictly preda tory life to one in which agriculture became important. In view of the anti quity of concern with the subject, it is perhaps surprising that it can be approached from a fresh viewpoint, as is done in this book. Because soil science is an applied science, it is not surprising that the approach is usually descriptive, rather than imaginative. For agriculturalists and other land users, perhaps the most important part of soil science is the description of soils and the capacities of such soils to maintain crops, and this is reflected by the fact that soil science is usually treated ima highly descriptive manner, with soil classification being one of the main efforts. The treatment of the subject from a geological point of view, with considerable emphasis on the evolution of soils and the reasons governing their composition and form, makes this a highly readable book. Books on soil science are timely, with present-day concern with such major problems as the pollution of our environment and the possibility of overreaching our capacity for producing food for an expanding population.

J. J. Beukema, w. J. Wolff & J. J. W. M. Brouns Man is changing the biosphere at an ever increasing Netherlands ministery of Housing, Physical Planning rate. Several of these man-made changes are on a and Health (represented by Dr. G. P. Hekstra), chaired worldwide scale, such as the increase in atmospheric by Dr. w. J. Wolff (Research Institute for Nature concentrations of several gases. In particular the Management) and housed by the Netherlands In ongoing increase of the concentration of at stitute for Sea Research (N. I. O. Z., represented by Dr. mospheric carbon dioxide, by excessive burning of J. J. Beukema). fossil fuels and forest destruction, is well The written versions of the presentations by 23 par documented. By the year 2050, CO levels will ticipants have been brought together in these pro 2 almost certainly be twice the pre-industrial concen ceedings of the Workshop. trations and this is expected to have far-reaching consequences. Direct effects include higher rates of The first paper, by G. P. HEKSTRA, explains how plant production (also in agriculture). Indirect effects trace gases affect UV-B radiation, alkalinity of the might be less favourable: by the intensified sea, rate of photosynthesis, and greenhouse warm 'greenhouse process' (to which several other gases ing."

In the past decades, environmental scientists, economists and physicists have been juggling critical issues within environmental strategies and environmental management styles in order to find a feasible medium between limited resources, long term demands and objectives, and interest groups. In the search for best management alternatives, practice has undergone a pendulum swing between stages that can be characterised as frontier economics, radical environmentalism, resource management/allocation, selective environmentalism and sustainable environmental management. The next stage of management must answer such questions as: Can there be a global - uniform environmental strategy?', or Based on their characteristics, can different issues, different regions and different applications have unique environmental strategies?' Based on this premise, the next stage of management may be identified as risk based sustainable environmental management. The goal of this style will be the risk based, long term, harmonious management of economic resources and environmental preservation for health, safety and prosperity of sustainable populations. When evaluation of risk or risk based ranking of management alternatives enter the picture as part of the overall puzzle, then social policy, ethics and health issues assume a very important role in the management strategy. Economic incentives and environmental constraints have to be considered harmoniously, the main emphasis being placed on protection and preservation of human health and the long term sustaining of populations.

It is the task of the engineer, as of any other professional person, to do everything that is reasonably possible to analyse the difficulties with which his or her client is confronted, and on this basis to design solutions and implement these in practice. The distributed hydrological model is, correspondingly, the means for doing everything that is reasonably possible - of mobilising as much data and testing it with as much knowledge as is economically feasible - for the purpose of analysing problems and of designing and implementing remedial measures in the case of difficulties arising within the hydrological cycle. Thus the aim of distributed hydrologic modelling is to make the fullest use of cartographic data, of geological data, of satellite data, of stream discharge measurements, of borehole data, of observations of crops and other vegetation, of historical records of floods and droughts, and indeed of everything else that has ever been recorded or remembered, and then to apply to this everything that is known about meteorology, plant physiology, soil physics, hydrogeology, sediment transport and everything else that is relevant within this context. Of course, no matter how much data we have and no matter how much we know, it will never be enough to treat some problems and some situations, but still we can aim in this way to do the best that we possibly can.

Earthquake Hazard and Risk is a book summarizing selected papers presented at the 27th General Assembly of the International Association of Seismology and Physics of the Earth's Interior (Wellington, January 1994). The papers, rigorously scrutinized by an international board of referees, cover some recent aspects of current research in earthquake hazard and seismic risk. They address the algorithms and methodology used in seismological applications, the reliability of these techniques with the decreasing level of probability and uncertainty associated with various seismotectonic settings, the physical and statistical nature of earthquake occurrences, strong ground motions and effects of surface seismogeological conditions. A special effort has been made to include papers that illustrate the assessment of earthquake hazard and seismic risk through applications at sites in either inter-plate or intra-plate tectonic settings. Of particular interest is hazard assessment in regions of rare large earthquakes. The book is suitable for those interested in earthquake hazard and seismic risk research as well as a more general audience of seismologists, geophysicists and Earth scientists. It is also useful for authorities responsible for public safety and natural hazard mitigation plans and for insurance companies.

Viewed from space, the Earth appears as a globe without a beginning or an end. Encompassing the globe is the atmosphere with its three phases- gaseous, liquid, and solid--moving in directions influenced by sunlight, gravity, and rotation. The chemical compositions of these phases are determined by biogeochemical cycles. Over the past hundred years, the processes governing the rates and reactions in the atmospheric biogeochemical cycles have typically been studied in regions where scientists lived. Hence, as time has gone by, the advances in our knowledge of atmospheric chemical cycles in remote areas have lagged substantially behind those for more populated areas. Not only are the data less abundant, they are also scattered. Therefore, we felt a workshop would be an excellent mechanism to assess the state of-knowledge of the atmospheric cycles of sulfur and nitrogen in remote areas and to make recommendations for future research. Thus, a NATO Advanced Research Workshop ' he Biogeochemical Cycling of Sulfur and Nitrogen in the Remote Atmosphere" was held at the Bermuda Biological Station, St. Georges, Bermuda, from 8-12 October 1984. The workshop was attended by 24 international scientists known for their work in atmospheric cycling in remote areas. This volume contains the back ground papers and the discussions resulting from that workshop. The workshop was organized along the lines of the atmospheric cycle. There were working groups on emission, transport, transformation, and deposi tion."

Next to air, water is the most essential of human requirements. The hydrosphere-the waters of the Earth, its oceans, rivers and lakes-is vital, constituting a feature unique in the solar system and one responsible for physical and climatic phenomena characteristic of the planet. Water moves through the hydrologic cycle and runs the heat engine of the Earth, approximately 97% of it occurring in the oceans. These contain vast natural resources including abundant plant and animal life and they assist in cleansing the atmosphere by becoming the final repository of air and land pollutants of which many are man-made. Unfortunately their ability to do this is diminishing because of rising pollution by toxicants such as DDT, nuclear by-products such as strontium-90 and oil spills. The oceans contain huge quantities of various substances mostly originating from the atmosphere, biological activity, river transport after rock weathering, groundwater, spreading zones along mid-oceanic ridges and crustal out-gassing. After hydrogen and oxygen, the commonest elements in them are Cl, Na, Mg, S, K, Ca, Br, C and B. The atmosphere and the oceans together cooperate in an energy cycle important in controlling and equalising the Earth's surface temperature.

The Workshop on Parameter Identification and Inverse Problems in Hydrology, Geology and Ecology, Karlsruhe, April 10-12, 1995, was organized to bring to gether an interdisciplinary group drawn from the areas of science, engineering and mathematics for the following purposes: - to promote, encourage and influence more understanding and cooperation in the community of parameter identifiers from various disciplines, - to forge unity in diversity by bringing together a variety of disciplines that attempt to understand the reconstruction of inner model parameters, un known nonlinear constitutive relations, heterogeneous structures inside of geological objects, sources or sinks from observational data, - to discuss modern regularization tools for handling improperly posed pro blems and strategies of incorporating a priori knowledge from the applied problem into the model and its treatment. These proceedings contain some of the results of the workshop, representing a bal anced selection of contributions from the various groups of participants. The reviewed invited and contributed articles are grouped according to the broad headings of hydrology, non-linear diffusion and soil physics, geophysical methods, mathematical analysis of inverse and ill-posed problems and parallel algorithms for inverse problems. Some of the issues adressed by the articles in these proceedings include the rela tion between least squares and direct formulations of inverse problems for partial differential equations, nonlinear regularization, identification of nonlinear consti tutive relations, fast parallel algorithms for large scale inverse problems, reduction of model structures, geostatistical inversion techniques.