This book contains most of the invited papers and contributions pre sented at the Symposium/Workshop on Solar-Terrestrial Influences on Weather and Climate which was held at The Ohio State University on 24-28 July 1978. The authors and publisher have made a special effort for rapid publi cation. The length of the individual papers in this book were delib erately limited by the editors. Direct financial support for the Symposium/Workshop was provided by NASA. Palo Alto Billy M. McCormac Columbus Thomas A. Seliga January 1979 xiii SYMPOSIUH/WORKSHOP CONCLUSIONS Billy M. McCormac Department 52-l0/B202 Lockheed Palo Alto Research Laboratory 3251 Hanover Street Palo Alto, CA 94304 USA Thomas A. Seliga Atmospheric Sciences Program The Ohio State University 2015 Neil Avenue Columbus, OH 43210 USA A. INTRODUCTION The Symposium/Workshop on Solar-Terrestrial Influences on Weather and Climate was held at The Ohio State University on 24-28 July 1978. Its purpose was to provide an international forum for the presentation and discussion of recent research results and ideas regarding the question whether variations in solar outputs affect terrestrial weather and cli mate and, if so, to what extent and through what mechanisms. The Sym posium focused on the results of previous studies and consisted of both invited and contributed papers. The Workshop, on the other hand, built upon these deliberations to develop ideas and directions for future research. Over one hundred persons from eight countries attended the Symposium/ Workshop.