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Tsunami Glossary: a Glossary of Terms and Acronyms Used in The Intergovernmental Oceanographic Commission technical series 37 Tsunami Glossary A Glossary of Terms and Acronyms Used in the Tsunami Literature UNESC01991 The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariats of UNESCO and IOC concerning the legal status of any country or territory, or its authorities, or concerning the delimitations of the frontiers of any country or territory. For bibliographic purposes this document should be cited as follows: Tsunami Glossary, IOC Tech. Ser. 37, UNESCO, 1991 (English) Published in 1991 by the United Nations Educational, Scientific and Cultural Organization 7, place de Fontenoy, 75700 Paris Printed in UNESCO’s Workshops © UNESCO 1991 Printed in France SC/91/WS/27 PREFACE Tsunami Science is a relatively new field dating only a few decades. It is only in the last fifty years that the tsunami scientific literature proliferated. Many terms from other disciplines were adopted, modified, revised, and applied to the studies of the tsunami phenomena. Many other terms were redefined in the context of the components of this new scientific field. This glossary is intended to list as many as possible of the terms found in the tsunami literature and provide their specific definitions. It is intended for students, scientists, administrators and for anyone interested in tsunami. This book contains concise definitions of more than 2,000 terms. It includes terms from a multitude of disciplines. Primary, specialized and frequently-used tsunami terms are given with bolder headwords. Less frequently used terms are not highlighted. As the tsunami scientific literature increases in the future, as our understanding becomes greater, and as our technology becomes more advanced, it is expected that new terms will be introduced. Such terms, and terms that have been omitted, will be included in a future edition. The present Glossary is viewed as an evolving document. ACKNOWLEDGMENTS No project of this magnitude goes forward without encouragement, support and helpful constructive criticism. I would like to thank ali the people who have reviewed drafts of this Glossary and provided comments and advice. I am very grateful to them ali. I would like to thank most particularly, the Intergovernmental Oceanographic Commission (IOC- UNESCO) and its International Coordination Group for the Tsunami Warning System in the Pacific (ICG/TTSU) for support of this project, and in particular, Dr. I. Oliounine of IOC and Mr. H. Hagemeyer, Chairman, ICG/ITS U for giving me deadlines and keeping me on schedule. Otherwise I could have been on this project for several more years. I wish to extend my appreciation to Professor S. L. Soloviev and his colleagues in the USSR for reviewing earlier listings of terms and providing comments that were useful in the development of this Glossary. Furthermore, I wish to express my appreciation to the ICG/ITS U committee members who reviewed proposed terms, recommended their adoptation and helped me differentiate between primary and secondary terms, for inclusion into the Glossary. Specifically, I wish to thank Dr. Mohammed El Sabh (Canada), Dr. Tad Murty (Canada), Mr. Emilio Lorca (Chile), Mr. James Lander (USA), and ali the others that served in this ICG/TTSU reviewing committee. Finally, I wish to thank Mrs. Millie Ching, ITIC Secretary, Mr. Loy Kuo, Graduate Assistant, Mr. Joseph Hunt, Mr. Joseph Edmon, Mr. Sam Kemer and ali the others, who helped with research, typing, computer formatting, and computer preparation of the first Edition of this Glossary. George Pararas-Carayannis Director International Tsunami Information Center (ITIC) of IOC ( iii ) Contents Introduction Background (vii) Philosophy of Glossary Development (viii) Tsunami Glossary 1 (v) INTRODUCTION Background At the first Workshop on the Technical Aspects of Tsunami Analyses, Prediction and Communications held at Sidney, B.C., Canada on 29 July - 1 August 1985, the following recommendation was made: "Recognizing that the diversity of terms used in describing the tsunami phenomenon which involves a wide variety of scientific and non-scientific groups in a variety of interdisciplinary fields, the Workshop recommends the preparation of a glossary of tsunami-related terms to serve as the basis for defining and understanding tsunami terminology." At the subsequent Tenth Session of the International Co-ordination Group for the Tsunami Warning System in the Pacific (ICG/TTSU) at the Institute of Ocean Sciences in Sidney, which followed the Tsunami Workshop, the Group accepted and adopted the recommendations proposed by the Workshop and requested the International Tsunami Information Center (ITIC) to take the necessary action for the implementation of this recommendation. In response to this ITSU-X recommendation, in August 1985, ITIC began the compilation of a "Glossary of Terms and Acronyms Used in the Tsunami Literature." A preliminary draft of the glossary with a total of about 2200 entries was distributed to the TTSU editorial group in early 1988 and a revised version in November 1988. These early drafts included a number of oceanographic, meteorological and physical terms that may have appeared as not necessary for inclusion. However, the original intent was to compile a comprehensive draft glossary and then, by a process of elimination, retain those terms that are more appropriate or likely to be found in the tsunami literature. Since November 1988, ITIC put a concerted effort to edit the earlier draft. A number of knowledgeable tsunami scientists were consulted as to what should be included in the glossary and a consensus of opinion was sought. In August 1989, at the ITSU XII meeting in Novosibirsk, USSR, the Director of ITIC presented the Group a final listing of Glossary terms compiled by ITIC and a listing of terms proposed by Dr. S. L. Soloviev. The Group noted that there was a diversion of opinion as to what terms should be included. The Chairman appointed a Sessional Group to review the proposed terms and to report to the Session those terms to be included in the first edition. After reviewing both listings and the philosophy of development of the ITIC-compiled listing, the Committee recommended the adoptation of the ITIC version into the Glossary, but stressed that a differentiation needed to be made between the primary glossary terms that relate directly to the tsunami problem, and the secondary terms that are indirect and of general interest. The Committee identified the primary terms, which in the present Glossary are distinguished by bolder print. With the recommendation of the editorial committee, the Group mandated that the first edition of the Tsunami Glossary should be published without delay and asked the Director, ITIC, to provide the final version of the Glossary, reflecting the recommendations of the Sessional Group to the 10C Secretariat by 15 August 1990. This date was later changed to 31 December 1990. Furthermore, the 10C Secretariat was to arrange the printing of the Glossary and its distribution to ITSU National Contacts. (Vii) Philosophy of Glossary Development The etymology of the word glossary comes from the Greek. Accordingly, the meaning of the word "glossary" signifies a term or a word which requires explanation or definition. A lexicographical compilation of pertinent words and terms with specific definition of usage and meaning is the basic prerequisite of every specialized discipline of science. This is very important as such words and terms are often used in different context or sense when applied to other disciplines or to spoken language. Furthermore, each discipline of science, as it develops, introduces its own specialized vocabulary which could be totally unfamiliar to others outside that particular field. The field we cali "tsunami" is a hybrid discipline of science encompassing principally, but not exclusively, aspects of solid earth geophysics and oceanography. As such, it has borrowed extensively terms and definitions from the many disciplines that comprise these fields, as well as from the basic sciences, engineering, and from mathematics. New specialized terms and definitions have aiso been introduced, some of them in languages other than English, which often elude universal acceptance and adoptation. Thus, there is a need to develop standardized tsunami terminology in the form of a glossary which has the endorsement of the appropriate scientific Groups. International research on the tsunami phenomenon has increased considerably in the last forty years as several destructive tsunamis have hit many Pacific countries. As a result, the tsunami scientific literature has proliferated. Interest in tsunamis and in the mitigation of tsunami disasters has aiso increased with the advent of new technology of data collection and communications and the development of early warning systems. Thus, a need has evolved for definition and proper usage of new terms which now appear frequently in the literature. The resulting philosophy is that a tsunami glossary should include, not only the direct terms related to tsunamis, but aiso terms from other fields of science that may be encountered by tsunami administrators or scientists, not only in their own field, but in peripheral fields of science or engineering where the terminology may be somewhat unfamiliar or utilized under a different context. Thus, the decision was made to include terms that are often being used in such diverse subjects
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