In most natural sciences, modeling is a widespread method of gaining new knowledge about natural and technical systems. This book analyses the concepts of 'model' and 'modeling' in different fields of research. The different methods of modeling as well as the potentials and limits of this concept are reflected and discussed. The book presents a variety of modeling techniques, from mathematical models in climatology, meteorology or oceanography to methods used in morphology, decision-making in ecology and physical modeling in oceanography. In this broad overview regarding modeling, the book is unique.

Written from the perspective of developing countries, this book discusses the development process from a spatial perspective, focussing particularly on the evoltuion of the intra-national space-economy. With emphasis on African nations, this book offers a distinctive interpretation of the current situation and policy prescriptions differing significantly from previous literature in the area.

The CLimatoLogy Research Programme of the Commi ssion of the European Communities started in 1980 after a few years of preparation which foLLowed the concern caused by the European drought of 1976. It was mainLy a concern about European Land and water resources, which then as never before appeared threatened by cLimate vagaries. It was mainLy an economic concern which Led the Commmission to propose, and the CounciL to adopt, a five-year piLot research programme which in the meantime has proved to be both usefuL and successfuL. The best speciaLists in many interreLated fieLds were brought together for the first time to join into a unique cooperation effort in the area of European cLimatoLogicaL research. The programme aLso enjoyed the efficient and competent cooperation of an Advisory Committee for Programme Management (ACPM) which, being essentiaLLy composed of cLimatoLogists, proved to be a scientific body of high quaLity, whose work has been one of the factors for the success of the programme. The Advisory Committee shared with the Services of the Commission the responsibiLity of preparing a Review Symposium, thought to be the best means of coLLecting and presenting the resuLts of the research performed during 1980-1984. This voLume contains the proceedings of that Review Symposium of the EC CLimatoLogy Research Programme, organized by the Directorate GeneraL of Science, Research and DeveLopment jointLy with the Centre d'Etudes et de Recherches Geodynamiques et Astronomiques (CERGA) at Sophia AntipoLis, France, 2-5 October 1984.

This book combines, for the first time, the topics of radar polarimetry and interferometry. This combination was first developed in 1997 and has since become a major topic in radar sciences and their applications, in particular to space sciences. In its simplest form it concerns the study of interferograms formed by combining waves with different polarisations and their exploitation to infer important physical properties of the planetary surface being investigated. The book is written in three main sections. The first four chapters provide a detailed coverage of all major topics of polarimetry, including its basis in electromagnetic scattering theory, decomposition theorems, and a detailed analysis of the entropy/alpha approach. The next chapter offers a brief introduction to radar interferometry, before developing in three chapters the important new topic of polarimetric interferometry. In this way the book provides a complete treatment of the subject, suitable for those working in interferometry who wish to know about polarimetry, or vice versa, as well as those new to the topic who are looking for a one-stop comprehensive treatment of the subject. The emphasis throughout is on the application of these techniques to remote sensing, and the book concludes with a set of practical examples to illustrate the theoretical ideas.

Fifteen years ago, approximately half the world population was estimated to live in continental and insular South-East Asia (Burma, Thailand, Kampuchea, Vietnam, Laos, Indonesia, Philippines). Then the region had a population growth of four million people every month, and the problem of malnutrition was acute for the rural population. International agricultural development organisations decided that their primary aim would be to double existing levels of agricultural production and, taking account of population growth, to double it again by the end of the century (Whyte 1976). Today, while global issues have greatly affected the parameters of the problem, the situation remains both serious and difficult. Despite impressive efforts in education and health, Indonesia for example, where population (179 millions) growth eased off only slightly between 1980 and 1990 (from 2. 3 percent to 1. 9 percent), is having to cope with increasing difficulties in managing natural resources and particularly its evanescent forest assets which, until 1986, were the second largest source of national revenue. Indonesia has the second largest surface area of tropical rain forests in the world (after Brazil) and thus all the problems linked with management and disappearance of those forests. The latest estimate gives a figure of 109 million hectares of forest in 1990, of which 40. 8 million hectares are production forests (Anon. -F AO 1990).

Als im ersten Band des Welt-Seuchen-Atlas vor erst einmal in Ubersichtskarten auf die geookologischen 10 Jahren einige Klimakarten uber Temperaturverhalt- Probleme aufmerksam zu machen. nisse und Niederschlage in Europa erschienen, wurde von Die Herausgeber mochten mit den in dieser Ausgabe einigen Kritikern nicht verstanden, warum einem Atlas vorgelegten Weltkarten zur Klimakunde denjenigen Wis- uber die Verbreitung von Seuchen Karten mit klimatolo- senschaftlern, die den Welt-Seuchen-Atlas benutzen, die gischen Angaben beigegeben wurden. Offensichtlich schien Moglichkeit einer Erganzung der darin befindlichen der Gewinn an Korrelationen zu gering, die aus den An- Klimakarten fur Untersuchung weiterer Korrelationen gaben uber klimatische Verhaltnisse zu dem Auftreten geben, aber auch allen biologisch und klimatologisch von Seuchen in den gleichen Gebieten gezogen werden interessierten Fachkreisen ein Hilfsmittel fur weitere konnten. Im zweiten Band wurde die Reihe der Klima- geookologische Forschungen zur Verfugung stellen. karten fur den afrikanischen Kontinent durch karto- Die bisher veroffentlichten Klimakarten, die fur die graphische Darstellungen der Regenzeiten und der Trok- ersten 3 Bande des Welt-Seuchen-Atlas von Professor Dr.

This "Catalogue of Typical Cases" was written between 1977 and 1981, based on examples supplied by the Compagnie Fran

F.K. Lehner: A Review of the Linear Theory of Anisotropic Poroelastic Solids. - J.W. Rudnicki: Eshelby's Technique for Analyzing Inhomogeneities in Geomechanics. - Y. Gueguen, M. Kachanov: Effective Elastic Properties of Cracked and Porous Rocks - an Overview. - J.L. Raphanel: 3D Morphology Evolution of Solid-Fluid Interfaces by Pressure Solution. - Y.M. Leroy: An Introduction to the Finite-Element Method for Linear and Non-linear Static Problems.

The mechanical behaviour of the earth's upper crust enters into a great variety of questions in different areas of the geological and geophysical sciences as well as in the more applied geotechnical disciplines. This volume presents a selection of papers from a CISM course in Udine on this topic. While each of these chapters will make for a useful contribution in its own right, the present bundle also illustrates, by way of examples, the variety of theoretical concepts and tools that are currently brought to bear on earth deformation studies, ranging from reviews of poroelastic field theory to micro-mechanical and homogenization studies, chemomechanics and interfacial stability theory of soluble solids under stress, and finally to an introduction to the finite element method.

Des Menschen Werk auf Erden kann vergehen, Doch Leben stets im Wandel wird bestehen. Heinrich Walter The importance of ecology for the fate of mankind is receiving ever wider recognition. A syncretic-holistic approach to ecology was recently given unexpected support by the well-known atomic physicist and pupil of Heisenberg, Fritjov Capra. In his book The Turning Point, published in 1982 in the U.S.A., Capra comments critically, from the viewpoint of the latest findings of subatomic physics, on the mechanical-analytical ap proach which still predominates in the biological sciences, and adds some philosophical reflections. The following quotations are important ecolo gically and may be of interest to biologists in general: "It is now becoming apparent that overemphasis on the scientific method and on rational, analytic thinking has led to attitudes that are profoundly anti-ecological. In truth, the understanding of ecosystems is hindered by the very nature of the rational mind. Rational thinking is linear, whereas ecological awareness arises from an intuition of non-linear systems .... The Cartesian view of the universe as a mechanical system provided a 'scientific' sanction for the manipulation and exploitation of nature that has become typical of Western culture .... The problem is that scientists, encouraged by their success in treating living organisms as machines, tend to believe that they are nothing but machines .... Modern physics can show the other sciences that scientific thinking does not necessarily have to be reductionist and mechanistic, that holistic and ecological views are also scientifically sound ...."

The analysis of polar ice cores has proven to be very instructive about past environmental conditions on the time scale of several climatic cycles, and recent drilling operations have provided information of great value for global change issues.
The book presents the most recent data extracted from Greenland ice cores and surface experiments and compares them with former Antarctic results. It contains background articles, original contributions and group reports of interest to scientists, climatologists, atmospheric chemists, and glaciologists involved in global change research.

The problern of "acid precipitation" has been recognized with growing concern in many industrialized countries. The incorporation of pollutants into cloud and rain elements and their transfer to the ground by "wet deposition" are dominant mechanisms leading to a self~cleansing of the tro- posphere but, on the other hand, to hazards to the soil, vegetation and forests. The influence of orographic and meteorological parameters and of the regional distribution of precipitation on the deposition of pollutants are insuffi- ciently known factors. During previous years, several projects and analyses have been initiated to improve our knowledge on the dry and wet deposition of pollutants and on the mechanisms of transport of gaseaus and particulate components from the atmosphere to the ground. Research activities have been supported in different fields and it appeared not only useful but necessary to bring the different research-groups tagether to endorse the communication and cooperation between scientists in the related fields. A symposiumwas arranged in Oberurself Taunus in November 1981 to discuss the results of experimen- tal and theoretical work in the field of deposition and to gain a better understanding of each other's methods, experience and Observations. The proceedings presented in this volume permit a fair sur- vey of the present-day knowledge and will be a useful tool for all working in this field. The meeting would not have been possible without the finan- cial support of the German Environmental Agency {Umwelt- bundesamt) .

1. 1 Solution of geological problems-are mathematical methods necessary? A question which is often asked is whether it is necessary for geologists to know and to use mathematics in the practise of their science. There is no simple answer to this question, and it is true that many geologists have had successful careers without ever needing to get involved in anything other than simple mathematics, and all the indications are that this is likely to continue into the future. However, in many branches of the subject the trend has been towards using a numerical approach for the solution of suitable problems. The extent to which this occurs depends on the nature of the area being studied; thus, in structural geology, which is con cerned in its simplest aspects with the geometrical relationships between various features, there are many problems which are easily solved. More recently the use of analytical methods has allowed the solution of more-difficult problems. In another area, geochemistry, two things have happened. On the theoretical side there has been a greater integration with physical chemistry, which itself is a highly mathematical subject; and on the practical side there is the need to analyse and interpret the vast quantities of data which modem instrumentation produces. Within geology the application of numerical methods has been given various names, so we have numerical geology, geo mathematics, geostatistics and geosimulation."

Proceedings of the NATO Advanced Research Workshop on The Long-Range Atmospheric Transport of Natural and Contaminant Substances from Continent to Ocean and Continent to Continent, St. Georges, Bermuda, January 10-17, 1988

Prominent progress in science is inevitably associated with controversies. Thus, young researchers, in particular, have to learn how to persevere during the period of controversy and struggle for acceptance. Unfortunately, the skills needed are not taught in textbooks or monographs, which mostly describe the consensus of contemporary experts.
This book, which is based on my own experiences as a scientist, describes the history of the progress made in auroral science and magnetospheric physics by providing examples of ideas, controversies, struggles, acceptance, and success in some instances.
Although no general methodology (if any exists) is mentioned, I hope that the reader will learn about the history of progress in auroral science and examples (right or wrong) of dealing with the controversies.

The International Conference on Differential Equations, theor*y, nu- merics and applications(ICDE'96-Bandung) was held successfully at the West Aula of Institut TeknoIogi Bandung on September 29 - October 2, 1996, hosted by the Center of Mathematics and the Department of Mathe- matics ITB. This was the first international conference on differential equa- tions in the region and attended by participants from 12 countries: Aus- tralia, Cambodia, Hong Kong, France, IndonE'sia, Malaysia, Netherlands, Philippine, Thailand, Singapore, USA and Vietnam. We would like to express our gratitude to the following organizations and institution: Directorate General of Higher Education of Indonesia (through Center Grant Project), Institut Teknologi Bandung, UNESCO (through Participating Programme and ROSTSEA Programme), European Economic Community(through the Joint Research Project between the Faculty of Ap- plied Mathematics, Universiteit Twente and the Department of Mathemat- ics, Institut Teknologi Bandung), South East Asian Mathematical Society (SEAMS), French Embassy in Jakarta and local sponsors for their generolls support which have made this conference possible.

The thermodynamics of the atmosphere is the subject of several chapters in most textbooks on dynamic meteorology, but there is no work in English to give the subject a specific and more extensive treatment. In writing the present textbook, we have tried to fill this rather remarkable gap in the literature related to atmospheric sciences. Our aim has been to provide students of meteorology with a book that can playa role similar to the textbooks on chemical thermodynamics for the chemists. This implies a previous knowledge of general thermodynamics, such as students acquire in general physics courses; therefore, although the basic principles are reviewed (in the first four chapters), they are only briefly discussed, and emphasis is laid on those topics that will be useful in later chapters, through their application to atmospheric problems. No attempt has been made to introduce the thermodynamics of irreversible processes; on the other hand, consideration of heterogeneous and open homogeneous systems permits a rigorous formulation of the thermodynamic functions of clouds (exclusive of any consideration of microphysical effets) and a better understanding of the approx imations usually implicit in practical applications."

Special functions enable us to formulate a scientific problem by reduction such that a new, more concrete problem can be attacked within a well-structured framework, usually in the context of differential equations. A good understanding of special functions provides the capacity to recognize the causality between the abstractness of the mathematical concept and both the impact on and cross-sectional importance to the scientific reality. The special functions to be discussed in this monograph vary greatly, depending on the measurement parameters examined (gravitation, electric and magnetic fields, deformation, climate observables, fluid flow, etc.) and on the respective field characteristic (potential field, diffusion field, wave field). The differential equation under consideration determines the type of special functions that are needed in the desired reduction process. Each chapter closes with exercises that reflect significant topics, mostly in computational applications. As a result, readers are not only directly confronted with the specific contents of each chapter, but also with additional knowledge on mathematical fields of research, where special functions are essential to application. All in all, the book is an equally valuable resource for education in geomathematics and the study of applied and harmonic analysis. Students who wish to continue with further studies should consult the literature given as supplements for each topic covered in the exercises.

Systems and their mathematical description play an important role in all branches of science. This book offers an introduction to mathematical modeling techniques. It is intended for undergrad students in applied natural science, in particular earth and environmental science, environmental engineering, as well as ecology, environmental chemistry, chemical engineering, agronomy, and forestry. The focus is on developing the basic methods of modeling. Students will learn how to build mathematical models of their own, but also how to analyze the properties of existing models. The book neither derives mathematical formulae, nor does it describe modeling software, instead focusing on the fundamental concepts behind mathematical models. A formulary in the appendix summarizes the necessary mathematical knowledge. To support independent learners, numerous examples and problems from various scientific disciplines are provided throughout the book. Thanks in no small part to the cartoons by Nikolas Sturchler, this introduction to the colorful world of modeling is both entertaining and rich in content

Throughout the nineteenth century, Britain remained hungry for minerals to fuel her industrial and economic growth. Archibald Liversidge (1846-1927) found his knowledge and research to be in high demand. He had studied at the Royal College of Chemistry, and then obtained an exhibition to Cambridge, where he founded the Cambridge University Natural Sciences Club. At just twenty-seven years old Liversidge was appointed Reader in Geology at the University of Sydney, where he revolutionized the study of minerals and their potential applications. First published in 1876, and reprinted here from the enlarged, third edition of 1888, his chemical audit of the minerals of New South Wales became a key text for students of this field. Divided into two sections that address metallic and non-metallic minerals in turn, and incorporating a detailed map and substantial appendix, this work is of enduring interest and importance to geologists, chemists and historians of science.

During the last decades, continuum mechanics of porous materials has achieved great attention, since it allows for the consideration of the volumetrically coupled behaviour of the solid matrix deformation and the pore-fluid flow. Naturally, applications of porous media models range from civil and environmental engineering, where, e. g. , geote- nical problems like the consolidation problem are of great interest, via mechanical engineering, where, e. g. , the description of sinter materials or polymeric and metallic foams is a typical problem, to chemical and biomechanical engineering, where, e. g. , the complex structure of l- ing tissues is studied. Although these applications are principally very different, they basically fall into the category of multiphase materials, which can be described, on the macroscale, within the framework of the well-founded Theory of Porous Media (TPM). With the increasing power of computer hardware together with the rapidly decreasing computational costs, numerical solutions of complex coupled problems became possible and have been seriously investigated. However, since the quality of the numerical solutions strongly depends on the quality of the underlying physical model together with the experimental and mathematical possibilities to successfully determine realistic material parameters, a successful treatment of porous materials requires a joint consideration of continuum mechanics, experimental mechanics and numerical methods. In addition, micromechanical - vestigations and homogenization techniques are very helpful to increase the phenomenological understanding of such media.

Inside the epic quest to find life on the water-rich moons at the outer reaches of the solar system Where is the best place to find life beyond Earth? We often look to Mars as the most promising site in our solar system, but recent scientific missions have revealed that some of the most habitable real estate may actually lie farther away. Beneath the frozen crusts of several of the small, ice-covered moons of Jupiter and Saturn lurk vast oceans that may have existed for as long as Earth, and together may contain more than fifty times its total volume of liquid water. Could there be organisms living in their depths? Alien Oceans reveals the science behind the thrilling quest to find out. Kevin Peter Hand is one of today's leading NASA scientists, and his pioneering research has taken him on expeditions around the world. In this captivating account of scientific discovery, he brings together insights from planetary science, biology, and the adventures of scientists like himself to explain how we know that oceans exist within moons of the outer solar system, like Europa, Titan, and Enceladus. He shows how the exploration of Earth's oceans is informing our understanding of the potential habitability of these icy moons, and draws lessons from what we have learned about the origins of life on our own planet to consider how life could arise on these distant worlds. Alien Oceans describes what lies ahead in our search for life in our solar system and beyond, setting the stage for the transformative discoveries that may await us.

Die Radioaktivitat von Boden, Wasser und Luft ist ein klassisches Forschungs- gebiet der Geophysik, aus dessen Ergebnissen diese von jeher reichen Nutzen zieht: Fragen nach der Warmebilanz des Erdinnern, nach dem Alter der Erde und dem der Gesteine haben erst von hier aus eine befriedigende Losung gefunden; H ydro- logie und Balneologie verdanken der Radioaktivitat entscheidende Bereicherung; im Rahmen der Prospektion und Bodenforschung hat sie ihren Platz; in der Physik der Atmosphare bietet sie die wesentliche Grundlage zum Verstandnis der atmospharisch-elektrischen Erscheinungen; dem Meteorologen gibt sie neue Moglichkeiten zur Bearbeitung atmospharischer Austausch- und Transport- probleme. Die Moglichkeit der Injektion gewaltiger Mengen radioaktiven Materials in die Atmosphare und das Auftreten kunstlich-radioaktiver Elemente im geo- physikalischen Bereich als Folge von Spaltprozessen oder Wirkungen der kos- mischen Strahlung haben dieser engen Verbindung zwischen Radioaktivitat und Geophysik neue Impulse verliehen. Die im letzten J ahrzehnt gewonnenen neuen Erkenntnisse und Fortschritte ubertreffen bei weitem die in den rund 50 Jahren "klassischer" Periode erworbenen Einsichten und haben dazu neue Probleme, Aufgaben und Moglichkeiten aufgezeigt.