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.

This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

This material is based upon work supported by the National Science Foundation under Grant No. ATM-9316824. 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 National Science Foundation.

Library of Congress Catalog Card No. 94-67804

B-485

Cover: Reproduction of an oil painting titled J's Landscape by Edith Paipert Namias. The artist studied at the Corcoran School of Art and the American University. Exhibitions of her work have appeared in the Smithsonian, the Corcoran Biennial Exhibit, the Baltimore Museum, the University of Virginia, the George Washington University, and the National Collection of Paintings, among many others. She is represented in several collections, including those of the Argentine Embassy and the Watkins Gallery of American University. Edith and her husband Jerry, an internationally recognized pioneer in the study of climate variability, reside in La Jolla, California.