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NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competencies and with regard for appropriate balance.

Support for this project was provided by the National Oceanic and Atmospheric Administration under Contract No. 50-DKNA-5-00015. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the above-mentioned agency.

Library of Congress Catalog Card Number 98-88439
International Standard Book Number 0-309-06098-2

Additional copies of this report are available from:

National Academy Press
2101 Constitution Avenue, NW
Box 285
Washington, DC 20055
800-624-6242
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http://www.nap.edu

COVER: The Day It Happened, the oil painting reproduced on the cover of this book, is the work of Ilana Cernat of Bat-Yam, Israel. Dr. Cernat is linked to the world of intermediate-scale climate change through her son Michael Ghil, a member of the panel on Climate Variability on Decade-to-Century Time Scales. The Day It Happened (1988) is one of several of her paintings that express her concern for the future, particularly what sort of world we will be leaving to the generations to come. A lawyer by training and profession, Dr. Cernat began studying painting in her teens. Her work has been exhibited in Romania, Hungary, Israel, and the United States, and hangs in collections in other countries as well. Her 1989 painting The Eye of the Storm appeared on the cover of the 1995 NRC report on natural climate variability on decade-to-century time scales.

Copyright 1998 by the National Academy of Sciences. All rights reserved.

Printed in the United States of America