In 1837 a comprehensive discussion of lightning appeared in the Annual of the French Bureau des Longitudes with a section on ball lightning which provided for the first time a readily available source in the scientific literature of the basic properties of this curious natural phenomenon. The author, Francois Arago, was the dominant influence in the French Academy of Sciences in the nineteenth century, having become a member of that august body at the age of twenty-three. His attention alone doubtless served at that time to establish the validity of scientific interest in the problem. In addition his discussion covered some of the major questions associated with ball lightning in a nota bly clear-sighted, effective style. Later reconsideration of the same questions often provided no significant improvement over Arago's discussion. There followed a dauntless band of varying but always small number who attempted to account for an apparently simple natural occurrence, a ball of fire usually seen in thunderstorms, with the best knowledge that advancing science could provide. All attempts to deal with this phenomenon were in variably frustrated. The characteristics of ball lightning could be readily cataloged, but they firmly resisted both experimental reproduction and theo retical explanation. One may say that to this day there is no explanation accepted by a large number of scientists. Several investigators of great ability and considerable accomplishment in different fields of science, including Faraday, Kelvin, and Arrhenius, took note of the problem.

During the last few decades anthropogenic activities in the industrially advanced countries have outcompeted nature in changing the global environment. This is best illustrated for example by the polluted lakes in Scandinavia and Canada, associated with acid deposition from fossil fuel combustion. One of the major challenges mankind is confronted with in the field of energy consumption is undoubtedly to ensure sustainability - a goal that requires improved management of natural resources and a substantial reduction of the noxious emissions which are dangerous to health and the environment. The threat of global climate change due to pollutant emissions causes se rious concern to many nations, and reaching an international consensus is likely to take some time. Carbon dioxide emissions have slowed only marginally in industrialized countries during the last few years, but have increased significantly in most developing countries due to increases in energy demand and the increasing use of fossil fuels, which remain the most readily available energy sources today. Unfortunately, far from learning lessons from the negative experiences of developed countries, many developing countries are taking the same path to development which has turned out to result in serious environmental consequences."

Since founding at the 23rd International Geological Congress in Prague in 1968, the International Association for Mathematical Geology has organized sessions in conjunction with the Congress. The 27th IGC in Moscow was no exception and the IAMG again held sessions and assisted the Congress in organizing Section 20 -Mathematical Geology and Geological Information ( D. F. Merriam, D. A. Rodionov, and R. Sinding-Larsen, conveners). All together 128 abstracts were published in the technical proceedings. Several of the papers were published prior to the Congress, others were not available, and others deemed not appropriate for publication in this volume. This collection then contains those papers aVailable and representative of the sessions. The collection is truly international with contributions from Canada, China, France, Poland, the UK, USA, and USSR. They are representative of the state-of-the-art as of the early 1980s in a variety of fields. The application of geomathematics/geostatistics to geological problems has been hastened by the availability of computers. These papers reflect that orientation -most of the results would not have been possible without the use of computers. Most of the approaches utilize techniques readily aVailable and adapted to solving geological problems -simulation, image analysis, decision theory, fuzzy sets, etc. However, one area, that of geostatistiques which includes Kriging, has been designed especially for use by earth scientists of the French school to solve geological problems.

These papers stem from the ISOTT Meeting held at Churchill College, Cambridge, from July 27th to 30th, 1986. Although the sun did not shine so brightly as during the Cambridge meeting in 1977, the communications and discussions were as lively and informative and some heat, as well as light, was generated in the presentation of differing views. The meeting was conducted in a generally informal way which allowed maximum time for discussion but the relatively unstructured nature of the debates made them unsuitable for publication. The amount of editing necessary meant that the printed version of the exchanges would bear little resemblance to the original, hence their omission. All the papers presented here have been scrutinized and retyped in a standard format. However, the diverse interests of ISOTT's members, reflected in the wide spectrum of the material submitted, made total editorial uniformity an unrealistic goal. Complete consistency in the use of symbols, abbreviations and units seemed less important than speed of publication.

In dem Jahrzehnt von 1952 bis 1961 ist in der Geo- ben einen statischen Charakter, sie lassen sich nicht zur Be- medizinischen Forschungsstelle der Heidelberger Aka- antwortung der Fragestellungen der Geomedizin verwen- demie der Wissenschaften in Heidelberg der Welt-Seuchen- den, die eine Erklarung der regionalen Unterschiede und Atlas bearbeitet worden. Zum ersten Male wurde der eine Prognose der weiteren Gefahrung zum Ziele haben. Versuch gemacht, mit Hilfe der medizinischen Karto- Krankheiten haben nicht nur eine Geschichte, sondern graphie Korrelationen zwischen dem Vorkommen von ihr Vorkommen und ihre Verbreitung auf der Erde Infektionskrankheiten, der Verbreitung ihrer Ubertrager ist auch raumlich differenziert. Eine Geographie der Krankheiten ist daher wissenschaftstheoretisch ebenso und Geofaktoren, die eine seuchenhafte Ausbreitung her- vorrufen oder fordern, in Weltkarten und Kontinentkar- gerechtfertigt wie eine Geschichte der Medizin als ein ten sichtbar zu machen. Dieses Kartenwerk sollte eine besonderes Teilgebiet der medizinischen Wissenschaft. Information uber den Stand der Seuchenverbreitung in Eine ganze Reihe von Krankheiten tragen sogar geo- graphische Herkunftsbezeichnungen, wie z. B. Indische der Welt bis zur Mitte unseres Jahrhunderts geben, dem Unterricht dienen und zur weiteren geomedizinischen Cholera, Asiatische Grippe, Mittelmeerfieber, Felsenge- Forschung anregen. Bei vielen Seuchen mussten aber erst birgsfieber u. a.

Recent progress in numerical methods and computer science allows us today to simulate the propagation of seismic waves through realistically heterogeneous Earth models with unprecedented accuracy. Full waveform tomography is a tomographic technique that takes advantage of numerical solutions of the elastic wave equation. The accuracy of the numerical solutions and the exploitation of complete waveform information result in tomographic images that are both more realistic and better resolved. This book develops and describes state of the art methodologies covering all aspects of full waveform tomography including methods for the numerical solution of the elastic wave equation, the adjoint method, the design of objective functionals and optimisation schemes. It provides a variety of case studies on all scales from local to global based on a large number of examples involving real data. It is a comprehensive reference on full waveform tomography for advanced students, researchers and professionals.

In the last decades, new experimental and numerical techniques have taken many advanced features of porous media mechanics down to practical engineering applications. This happened in areas that sometimes were not even suspected to be open to engineering ideas at all. The challenge that often faces engineers in the field of geomechanics, biomechanics, rheology and materials science is the translation of ideas existing in one field to solutions in the other. The purpose of the IUTAM symposium from which this proceedings volume has been compiled was to dive deep into the mechanics of those porous media that involve mechanics and chemistry, mechanics and electromagnetism, mechanics and thermal fluctuations of mechanics and biology. The different sections have purposely not been formed according to field interest, but on the basis of the physics involved.

This book on electromagnetic resonance phenomena describes a general approach to physical problems, ways to solve them, and properties of the solutions obtained. Attention is given to the discussion and interpretation of formal and experimental data and their links to global atmospheric conditions such as the dynamics of global thunderstorm activity, variations of the effective height of the lower ionosphere, etc.

Schumann resonance is related to worldwide thunderstorm activity, and simultaneously, to global properties of the lower ionosphere. Transverse resonance is predominantly a local phenomenon containing information on the local height and conductivity of the lower ionosphere and on nearby thunderstorm activity.

Transient events in ELF-VLF radio propagation are also treated. These are natural pulsed radio signals and/or abrupt changes of manmade VLF radio signals. The transients associated with cloud-to-ionosphere discharges (red sprites, blue jets, trolls) are discussed, and clarification of the underlying physical ideas and their practical applications to pioneer results achieved in the field recently are emphasised.

The book presents a comprehensive overview of the current state-of-the-art in the atmospheric boundary layer (ABL) research. It focuses on experimental ABL research, while most of the books on ABL discuss it from a theoretical or fluid dynamics point of view. Experimental ABL research has been made so far by surface-based in-situ experimentation (tower measurements up to a few hundred meters, surface energy balance measurements, short aircraft experiments, short experiments with tethered balloons, constant-level balloons, evaluation of radiosonde data). Surface flux measurements are also discussed in the book. Although the surface fluxes are one of the main driving factors for the daily variation of the ABL, an ABL description is only complete if its vertical structure is analyzed and determined. Satellite information is available covering large areas, but it has only limited temporal resolution and lacks sufficient vertical resolution. Therefore, surface-based remote sensing is a large challenge to enlarge the database for ABL studies, as it offers nearly continuous and vertically highly resolved information for specific sites of interest. Considerable progress has been made in the recent years in studying of ground-based remote sensing of the ABL. The book discusses such new subjects as micro-rain radars and the use of ceilometers for ABL profiling, modern small wind lidars for wind energy applications, ABL flux profile measurements, RASS techniques, and mixing-layer height determination.

The background This volume contains the proceedings of the first International symposium on "Non-C0 Greenhouse Gases: Why and How to 2 Control?" held in Maastricht, The Netherlands from 13-15 Decem ber 1993. Of the known greenhouse gases, political attention to date has been primarily focused on carbon dioxide (C0 ) and the 2 CFCs - the latter because of their interaction with stratospheric ozone. The other greenhouse gases, notably methane (CH ), nitrous 4 oxide (N 0), HCFCs, HFCs and tropospheric ozone and its precur 2 sors nitrogen oxides (NO), carbon monoxide (CO) and volatile organic compounds (VOCs), may appear collectively to be of equal importance for global warming but have attracted less attention. Nevertheless, a comprehensive approach to climate change respon se, taking into account all sources and sinks of all greenhouse gases, is explicitly allowed in the Framework Convention on Clima te Change. The Netherlands' policy on climate already addresses all greenhouse gases. In order to stimulate the development of international climate policy on this subject, the Dutch Ministry of Housing, Physical Planning and Environment supported the initative of organizing an international symposium on the science and policy of the non-C0 greenhouse gases. An important rationale behind 2 this initative was recognizing that for the non-C0 greenhouse 2 gases, abatement options are available that do not only address other environmental problems but that also do not require the major structural changes in society that an effective CO policy 2 may."

This volume presents selected papers from the IUTAM Symposium on Reynolds Number Scaling in Turbulent Flow, convened in Princeton, NJ, USA, September I1-13, 2002. The behavior ofturbulence at high Reynolds number is interesting from a fundamental point of view, in that most theories of turbulence make very specific predictions in the limit of infinite Reynolds number. From a more practical point of view, there exist many applications that involve turbulent flow where the Reynolds numbers are extremely large. For example, large vehicles such as submarines and commercial transports operate at Reynolds 9 numbers based on length ofthe order oft0 , and industrial pipe flows cover a 7 very wide range of Reynolds numbers up to 10 * Many very important applications of high Reynolds number flow pertain to atmospheric and other geophysical flows where extremely high Reynolds numbers are the rule rather than the exception, and the understanding of climate changes and the prediction of destructive weather effects hinges to some extent on our appreciation ofhigh-Reynolds number turbulence behavior. The important effects of Reynolds number on turbulence has received a great deal of recent attention. The objective of the Symposium was to bring together many of the world's experts in this area to appraise the new experimental results, discuss new scaling laws and turbulence models, and to enhance our mutual understanding of turbulence.

The Sixth Conference on Ultra-Wideband, Short-Pulse Electromagnetics (UWB SP6), chaired by Eric Mokole of the United States Naval Research Laboratory (NRL) and hosted by the NRL and the United States Naval Academy (USNA), was held at the USNA in Annapolis Maryland (USA) from 3-7 June 2002. UWB SP6 was part of the AMEREM 2002 Symposium, chaired by Terence Wieting of the NRL. AMEREM 2002 continued the series of international conferences that were held in: Brooklyn New York at the Polytechnic University in 1992 and 1994; Albuquerque New Mexico in 1996 as part of AMEREM '96; Tel-Aviv Israel in 1998 as part of EUROEM '98; and Edinburgh Scotland in 2000 as part of EUROEM 2000. The next conference (UWB SP7) will be held from 12-16 July 2004 at Otto von Guericke University in Magdeburg Germany (EUROEM 2004) and will be chaired by Frank Sabath. The purpose of these meetings is: to focus on advanced technologies for the generation, radiation, and detection of ultrawideband (UWB) short-pulse signals, taking into account their propagation about, scattering from, and coupling to targets and media of interest; to report on developments in supporting mathematical and numerical methods; and to describe current and potential future applications of the technology. The session topics of UWB-SP6 included electromagnetic theory, scattering, UWB antennas, UWB systems, ground penetrating radar (GPR), pulsed,. power generation, time-domain computational electromagnetics, UWB compatibility, target detection and discrimination, propagation through dispersive media, and wavelet and multi-resolution techniques.

The NATO Advanced Research Workshop on Coupling Processes in the Lower and Middle atmosphere held in Loen, Norway in May 1992 was, in the estimation of apparently all participants, an enormous success. The 18 invited speakers included many of the leaders in the field and resulted in the attendance of a large number of contributing speakers and observers. The subject of the workshop was itself very timely, given the increasing awareness within the international community of the sensitivity of the atmosphere to coupling between adjacent layers, different latitudes, and various scales of motion. It was also very beneficial to bring together researchers with different approaches to the same or similar problems. For example, experimentalists benefitted from the inputs of modelers and theoreticians concerning the needs of current models and the most pressing problems and unknowns. Likewise, theoreticians were challenged to apply themselves to realistic problems and saw their theories tested against geophysical data. These discussions led to meaningful exchanges of ideas and challenges to or displacement of conventional wisdom in some areas. Indeed, possibly the greatest benefit of the workshop was the exposure of many participants to other areas of research or approaches to problems relevant to their own work. Workshop topics were confined to dynamical coupling processes in order to examine progress in a relatively focussed area. Nevertheless, the results presented spanned spatial scales from molecular to global and temporal scales from seconds to decades.

Since the first international conference on urban air quality, held at the University ofHertfordshire in 1996, significant advances have taken place in the field of urban air pollution. In addition to the scientific advances in the measurement, modelling and management of urban air quality, significant progress has been achieved in relation to the establishment of major frameworks to ensure a more effective mechanism for international collaboration. Two such frameworks are SATURN (Studying Atmospheric Pollution in Urban Areas) and TRAPOS (Optimisation of Modelling Methods for Traffic Pollution in Streets). In response to such advances, the second international conference was held at the Technical University of Madrid in March 1999 with active participation of SATURN and TRAPOS investigators. The organisation of the conference was headed by the Institute of Physics in collaboration with the Technical University of Madrid and the University of Hertfordshire. The support of IUAPPA and AWMA ensured a truly worldwide promotion and participation. The meeting attracted 140 scientists from 26 different countries establishing it as a major forum for exchanging and discussing the latest research fmdings in this field.

Linking People, Place, and Policy: A GIScience Approach describes a breadth of research associated with the study of human-environment interactions, with particular emphasis on land use and land cover dynamics. This book examines the social, biophysical, and geographical drivers of land use and land cover patterns and their dynamics, which are interpreted within a policy-relevant context. Concepts, tools, and techniques within Geographic Information Science serve as the unifying methodological framework in which landscapes in Thailand, Ecuador, Kenya, Cambodia, China, Brazil, Nepal, and the United States are examined through analyses conducted using quantitative, qualitative, and image-based techniques.

Linking People, Place, and Policy: A GIScience Approach addresses a need for a comprehensive and rigorous treatment of GIScience for research and study within the context of human-environment interactions. The human dimensions research community, land use and land cover change programs, and human and landscape ecology communities, among others, are collectively viewing the landscape within a spatially-explicit perspective, where people are viewed as agents of landscape change that shape and are shaped by the landscape, and where landscape form and function are assessed within a space-time context. This book articulates some of these challenges and opportunities.

Introduced to the technical aspects of forestry aerial spraying in the mid-1970's, we were immediately impressed by the complexity of the process of delivering pesticide to foliage. At that time, there was a vigorous public debate in New Brunswick about the ecological and public h~alth impacts of the annual spray program for the control of defoliation of spruce and fir trees by the spruce budworm. The forest industry is important to the province and changes to the established procedures of budworm control could have major economic implications. A rational debate required reliable information about the mechanics of the spraying process. There was a need to supply missing information as to required pesticide application rates, atomizer performance, off-target drift and deposit, and the effects of weather and aircraft operating factors. We were invited to initiate a research program in this domain by New Brunswick forest management officials, and what follows in this book is a logical and quantitative description of the overall process based on our own research and that of others over the intervening years. After a short introduction to aerial spraying, we begin (Chapter 2) by describing forest stands in terms of their interaction with suspended atmospheric particulate material carried along by the wind and susceptible to deposition on foliage. We introduce foliage simulators and their use in measuring the deposit of sprayed pesticide on foliage, the "biological interface" between pest and pesticide.

Summary of the NATO Advanced Research Workshop on Physical Signatures of Magnetospheric Boundary Layer Processes T A POTEMRA, M I PUDOVKIN, R W SMITH, V M VASYLIUNAS and A EGELAND 451 PREFACE These proceedings are based on the invited talks and selected research reports presented at the NATO Advanced Workshop on "PHYSICAL SIGNATURES OF MAGNETOSPHERIC BOUNDARY LAYER PROCESSES", held at Sundvolden Hotel, Norway, 9.-14.May 1993. The international political and scientific communities have gradually realized that the Earth's environment is more fragile than previously believed. This has led to the establishment of international research programmes directed toward the understanding of "Global Change". The Earth's magnetosphere, "the Earth-space", is a part of our environment, and physical processes in the magnetosphere and coupling between the solar energy stream, the solar wind, and the Earth-space are important in the complete understanding of our environment. Variations in the electromagnetic and particle energy output of the Sun have a significant effect on global changes. The energy transfer mechanisms at the days ide magnetospheric boundary layers and their ionospheric signatures are perhaps even more important to solar terrestrial research than the night-side processes in this connection. The dayside boundary layers and the polar cusps are the Earth's windows to outer space. The present NATO ARW was the latest in a series of conferences focused on dayside magnetospheric phenomena. It is five years since the preceding Workshop on "Electromag netic Coupling in the Polar Clefts and Caps" was held at Lillehammer in September 1988.

Only a few laboratories in the world have taken the bold step to attempt the integration of sub-models of the climate system, the global biogeochemical cycles and the human/societal components. This volume reports such a major undertaking and it is an important step towards an integrated approach to global change science. The IMAGE 2 model is important in demonstrating our current ability to model the complex global system.

The workshop on "Optical Properties of Low Dimensional Silicon sL Structures" was held in Meylan, France on March, I yd, 1993. The workshop took place inside the facilities of France Telecom- CNET. Around 45 leading scientists working on this rapidly moving field were in attendance. Principal support was provided by the Advanced Research Workshop Program of the North Atlantic Treaty Organisation (NATO). French Delegation a l'Armement and CNET gave also a small financial grant, the organisational part being undertaken by the SEE and CNET. There is currently intense research activity worldwide devoted to the optical properties of low dimensional silicon structures. This follow the recent discovery of efficient visible photoluminescence (PL) from highly porous silicon. This workshop was intended to bring together all the leading European scientists and laboratories in order to reveal the state of the art and to open new research fields on this subject. A large number of invited talks took place (12) together with regular contribution (20). The speakers were asked to leave nearly 1/3 of the time to the discussion with the audience, and that promoted both formal and informal discussions between the participants.

Funding Science: An Immense Challenge The real challenge in science should be hypothesis formation, experimental design and conducting the actual research under rigorous control and experimental condi of tions with the best available equipment/infrastructure. However, in many parts the world, the real challenge in science is trying to obtain some minimal amount of funding to initiate research. Every country in the world is challenged with an im mense number of interconnected environmental and health problems. Examples in clude biologically and chemically contaminated water and soil, air pollution, waste and sewage treatment, a multitude of infectious diseases in humans, animals and plants, global change, population growth, alternate energy sources, deforestation, floods, crop production and so on. Solutions to these national and international problems require training and re search to ensure the best available people and knowledge are available to man age and/or solve these problems. This can only be accomplished if the research community has the funding to conduct priority research and apply the knowledge globally. The challenge in science should be discovering the unknown and col laborative research/training of new scientists. Too often the challenge is how to conduct research without proper support. Many scientists are likely of the opinion that it is not their jobs/careers that is stressful, but the inability to do their research properly, that is stressful. Good research in a knowledge based economy requires proper funding.

Mohamed Larbi Selassi Deputy Director of the National Meteorology, Morocco Welcome address (translated from French) WMO, WCRP, Medias-France and scientific institutions representatives, ladies and gentlemen, to thank WMO and MEDIAS-France, who have honoured us by I want first organizing the two workshops, climate indices in Africa and data assessment for global change research in the Mediterranean region, in Casablanca and I welcome all of you here in Morocco. It is with great pleasure that I open these two workshops on behalf of myself and on behalf of the Direction of the Meteorologie N ationale of Morocco. Climate change is becoming the focus of the international community because of its global scale and unpredictable effects, the numerous impacts it causes, its global feature and the complexity of the solutions that can mitigate its impacts. Global warming and the greenhouse effect became a subject of study at the international level since the United Nations Conference on the human environment that was held in Stockholm in 1972. The research and coordination efforts that have been made in this area have led to an "International Scientific consensus". High level meetings like those held in Toronto in 1988, in Lahaye in 1989 and in Geneva in 1990, did confirm the greenhouse threat and the emergency to treat it.

As the regional models required to understand and control the generation, distribution and deposition of air pollutants become more precise, the need to understand the detailed effects of hilly and mountainous terrain becomes more acute. The Alpine regions and the mountainous Mediterranean coasts have large effets on the way the pollutant burden is spread in their areas. Similarly an understanding of the effects of chemical and physical processes controlling pollutant deposition and the emission of biogenic compounds is essential to the correct modelling of the coastal regions which surround so much of Europe.
The results from two projects on these problems are presented in this volume: one involved a series of field campaigns in the Alps and in the Rhine valley, the other involves ships and platforms in the North Sea and also in the Mediterranean.

This volume contains the lectures presented at the second course of the International School of Space Chemistry held in Erice (Sicily) from October 20 - 30 1991 at the "E. Majorana Centre for Scientific Culture." The course was attended by 58 participants from 13 countries. The Chemistry of Life's Origins is well recognized as one of the most critical subjects of modem chemistry. Much progress has been made since the amazingly perceptive contributions by Oparin some 70 years ago when he first outlined a possible series of steps starting from simple molecules to basic building blocks and ultimate assembly into simple organisms capable of replicating, catalysis and evolution to higher organisms. The pioneering experiments of Stanley Miller demonstrated already forty years ago how easy it could have been to form the amino acids which are critical to living organisms. However we have since learned and are still learning a great deal more about the primitive conditions on earth which has led us to a rethinking of where and how the condition for prebiotic chemical processes occurred. We have also learned a great deal more about the molecular basis for life. For instance, the existence of DNA was just discovered forty years ago.

Measurements of solar irradiance, both bolometric and at various wavelengths, over the last two decades have established conclusively that the solar energy flux varies on a wide range of time scales, from minutes to the 11-year solar cycle. The major question is how the solar variability influences the terrestrial climate. The Solar Electromagnetic Radiation Study for Solar Cycle 22 (SOLERS22) is an international research program operating under the auspices of the Solar-Terrestrial Energy Program (STEP) Working Group 1: The Sun as a Source of Energy and Disturbances'. STEP is sponsored by the Scientific Committee of Solar-Terrestrial Physics (SCOSTEP) of the International Council of Scientific Unions (ICSU). The main goal of the SOLERS22 1996 Workshop was to bring the international research community together to review the most recent results obtained from observations, theoretical interpretation, empirical and physical models of the variations in the solar energy flux and their possible impact on climate studies. These questions are essential for researchers and graduate students in solar-terrestrial physics.

This volume is on the flexibility mechanisms of the Kyoto Protocol and summarises the main fmdings of a two day workshop on 'Dealing with Carbon Credits after Kyoto', organised by ETC and the JIN foundation (both from the Netherlands) in Callantsoog, the Netherlands, on 28-29 May 1998. The workshop was one of the fIrst meetings held on the flexibility mechanisms after the Kyoto Protocol had been accepted at the Third Conference of the Parties (CoP3) in Kyoto, Japan, in December 1997. During the workshop it became clear that during the stage of translating the Protocol provisions on the flexibility mechanisms (notably Articles 6, 12 and 17) into concrete action, there are still many questions on how to interpret the scope and meaning of the Protocol text precisely. Indeed, various issues need to be elaborated on before a full assessment of the future practical work - the start of CDM and JI projects and possibly international emissions trading - can be made. Several issues were addressed at the workshop: e. g. how and via which procedures to determine the net abatement of particular CDMIJI projects; who is liable for non compliance in international emissions trading; is there a need for credit sharing formulae; can incentives be provided for early action, etc.