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Part 1 Seminar on Possible Responses of Weather Phenomena to Variable NCAR LIBRARY 03422 . Proceedings of the Seminar on Possible Responses of Weather Phenomena to Variable Extra-Terrestrial Influences Workshop, June 16 to July 28, Open Meeting, July 29 and 30, 1965 Boulder, Colorado Ni,' .S 7 NCAR Technical Note, TN-8 NATIONAL CENTER FOR ATMOSPHERIC RESEARCH BOULDER, COLORADO 1965 NCARLibrary - V 5 0583 01011903 4 ERRATA Page 23 -- Under the text figure the following is missing: Time Page 37 -- The second figure caption is missing: Fig. 7 -- Sketch of a wind profile from Wallops Island that was obtained after a strong magnetic storm The National Center for Atmospheric Research (NCAR) is dedicated to the advancement of the atmospheric sciences for the benefit of mankind. It is operated by the University Corpora- tion for Atmospheric Research (UCAR), a private, university-controlled, non-profit organization, and is sponsored and principally,funded by the National Science Foundation. NCAR shares with other atmospheric research groups four interrelated, long-range objectives that provide justification for major expenditures of public and private funds: * To ascertain the feasibility of controlling weather and climate, to develop the tech- niques for control, and to bring about the beneficial application of this knowledge; * To bring about improved description and prediction of astrophysical influences on the atmosphere and the space environment of our planet; * To bring about improved description and prediction of atmospheric processes and the forecasting of weather and climate; * To improve our understanding of the sources of air contamination and to bring about the application of better practices of air conservation. The research and facilities operations of NCAR are conducted in four organizational entities: The Laboratory of Atmospheric Sciences The High Altitude Observatory The Facilities Division The Advanced Study Program All visiting scientist programs and joint-use facilities of NCAR are available to scientists from UCAR-member and non-member institutions (including private and government laboratories in the U.S. and abroad) on an equal basis. The member universities of UCAR are: University of Alaska Florida State University Pennsylvania State University University of Arizona University of Hawaii Saint Louis University University of California The Johns Hopkins University Texas A and M University University of Chicago Massachusetts Institute of Technology University of Texas Colorado State University University of Michigan University of Utah University of Colorado University of Minnesota University of Washington Cornell University New York University University of Wisconsin Proceedings of the Seminar on Possible Responses of Weather Phenomena to Variable Extra-Terrestrial Influences Workshop, June 16 to July 28, Open Meeting, July 29 and 30, 1965 Boulder, Colorado John E. Kutzbach, Editor Emmy H. Shakeshaft, Assistant NCAR Technical Note, TN-8 NATIONAL CENTER FOR ATMOSPHERIC RESEARCH BOULDER, COLORADO 1965 Conference Sponsors: Workshop, June 16 to July 28, 1965 - Sponsored by the Office of Naval Research and the National Center for Atmospheric Research. Open Meeting, July 29 and 30, 1965 - Sponsored by the American Meteorological Society, the Office of Naval Research, and the National Center for Atmospheric Research. iii FOREWORD Every morning at nine, a small group of regular participants in our seminar climbed the hill to the same blackboard-walled classroom, underneath the telescope dome at the High Altitude Observatory, where many of us had similarly met nine years be- fore to discuss closely related questions. There at HAO, for an hour and a half or more each morning, spirited discussions centered around an introductory and sometimes very informal paper aimed at some selected topic of the seminar. After this, each of us devoted the rest of the day to individual research projects, informal discussions, and other tasks. This document was put together principally to remind those of us who participated, in months to come, of clues and ideas that emerged in the morning sessions. The collection was assembled from notes and tape recordings -- by John Kutzbach, who, with the help of Emmy Shakeshaft, worked diligently as seminar recorder. Each "kickoff" talk is covered, sometimes in detail, sometimes more sketchily. The papers are not to be taken as formal or original publi- cations. Much of the material is derived, and not new. Much is not yet ready for publication, but reveals us, instead, thinking out loud before a blackboard. In these instances the summary is nothing more than a transcript of an informal debate -- and thus there are gaps in coverage of important contributions from the literature, and there is sometimes no definitive thread of logic pervading the arguments. In spite of these shortcomings in the document, we have felt that many who could not attend our sessions would like to know something of what went on. We are glad, in this way, to share our sometimes all-too-random thoughts. In the call to the seminar I quoted some brilliant and hortatory remarks of John R. Platt ("Strong Inference," Science, 146, No. 3642, 347-353, October 16, 1964). Platt urged people interested in things like the possible effects of anomalous solar radiation on weather to structure their thinking toward the development of chains of logical inference -- a process he called "strong inference." He urged, for complex systems like atmospheric science, that working hypotheses be developed, however speculative they might prove, so that systematic searches might be made, at each step, for alternatives and for critical tests to eliminate false elements of the tree of logic. We did not really meet this goal -- though some of us now feel more prepared to try. But we did focus on constructing plausible mechanisms to explain assumed relationships, rather than on delineating empirical-statistical findings or conducting iv arguments about whether or not such extra-terrestrial effects were "proven beyond reasonable doubt" instead of simply "strongly sug- gested," etc. The pages reflect, I think, some of this character. At least one "regular," whose contributions were of great value, remains convinced that the evidence is slender for a lunar influ- ence on heavy rainfall occurrences -- even though to explain this was a prime target of our deliberations. We divided up into three topic groups, with topic chairmen, as follows: Topic A. Chairman: C. Rooth -- Interactions between different types of motions in a deep, stratified atmosphere Topic B. Chairman: G. Brier -- Mechanisms involving the apparent influences of solar and lunar tidal forces on peak rain- fall and other meteorological phenomena Topic C. Chairman: W. O. Roberts -- Miscellaneous selected background or summary topics This document is arranged to reflect the topic areas. The long title of our seminar -- which went through several variants -- was quickly abbreviated to "extra-terrestrial influ- ences." Thus, the sign on the top floor of Hallett Hall, where many of us had our offices, bore simply that legend, under which some anonymous wit, early in our sessions, boldly marked in "Like God?" But, of course, our discussions were not quite that inter- disciplinary. The workshop was jointly sponsored, with NCAR, by the Office of Naval Research; the "wrap-up" meeting at the conclusion of the seminar was sponsored by the American Meteorological Society as well. We are grateful to these organizations. I want also to express deep appreciation to Glenn W. Brier, Claes Rooth, Paul Twitchell, Emmy Shakeshaft, and John Kutzbach, whose hard work went far toward making things a success. And, of course, many others -- full-term and occasional participants -- generously entered the spirit of our deliberations, and contributed magnificently. Walter Orr Roberts v PREFACE The presentations and discussions at the workshop moved from one topic to another depending on such things as the availability of speakers, the time required for preparing material and the pre- ferences of the participants. The material has been reorganized for presentation here to obtain a more logical grouping. The three general topics of this seminar are strongly interrelated and in some cases the inclusion of a presentation or discussion in a parti- cular section of these proceedings is rather arbitrary. The Table of Contents provides an additional brief outline of the subject matter. I vii CONTENTS Foreword . iii Preface . v Participants List .................... ... xi Topic A Interactions between Different Types of Motions in a Deep Stratified Atmosphere Summary paper presented at open meeting, C. Rooth . 3 * Certain aspects of stratospheric-mesospheric circulations and dynamics Global Circulations of the Stratosphere and Mesosphere, W. L. Webb .. ....................... 13 Thermal Tidal Effects in the Upper Stratosphere and Lower Mesosphere, W. L. Webb ................... 21 Motions in the 80 to 100 Kilometer Region, A. Kochanski. 27 Photochemical Interactions near the Mesopause, C. Leovy. 39 * Suggested models for studying possible dynamic interactions be- tween various levels in the atmosphere Models for Studying Interactions between Various Layers of the Atmosphere, C. Rooth. .......... .... 41 Dynamic Interactions, P. D. Thompson .. ....... 43 * Results of experiments with numerical models of the atmosphere Responses to Heating, E. N. Lorenz ...... ...... 47 Models of Atmospheric Circulation, E. B. Kraus . 59 Effects of High Level Heating on the Large-Scale Circulation of the Lower Atmosphere,
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