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THE SUN AS a VARIABLE STAR: SOLAR and STELLAR IRRADIANCE VARIATIONS Photograph of Participants of IAU Colloquium No

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THE SUN AS a VARIABLE STAR: SOLAR and STELLAR IRRADIANCE VARIATIONS Photograph of Participants of IAU Colloquium No THE SUN AS A VARIABLE STAR: SOLAR AND STELLAR IRRADIANCE VARIATIONS Photograph of participants of IAU Colloquium No. 143 'The Sun as a Variable Star: Solar and Stellar Irradiance Variations', held in Boulder, Colorado, June 20-25, 1993. Nearly 200 scientists participated in this meeting. THE SUN AS A VARIABLE STAR: SOLAR AND STELLAR IRRADIANCE VARIATIONS Proceedings of the 143rd Colloquium of the International Astronomical Un ion held in the Clarion Harvest House, Boulder, Colorado, June 20-25,1993 Edited by JUDITM.PAP Jet Propulsion Laboratory, MS 171-400, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, U.S.A. CLAUS FROHLICH Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Davos Dor/, Switzerland HUGH S. HUDSON 1nstitute for Astronomy, University of Hawaii, Honolulu, Hawaii, U.S.A. and W. KENT TOBISKA TELOSIJPL, MS 264-765, 4800 Oak Grove Drive, Pasadena, CA 91109, U.S.A. Reprinted from Solar Physics, Volume 152, No. 1, 1994 SPRINGER-SCIENCE+BUSINESS MEDIA, B.V. Library of Congress Cataloging-in-Publication Data ISBN 978-94-010-4410-3 ISBN 978-94-011-0950-5 (eBook) DOI 10.1007/978-94-011-0950-5 Printed on acid-free paper AII Rights Reserved © 1994 Springer Science+Business Media Dordrecht OriginalIy published by Kluwer Academic Publishers in 1994 Softcover reprint of the hardcover 1st edition 1994 No part ofthe material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written permis sion from the copyright owner. TABLE OF CONTENTS (The Sun as a Variable Star: Solar and Stellar [rradiance Variations) Preface ix 1. E. MARTIN and N. P. FOX / Cryogenic Solar Absolute Radiometer - CSAR H. L. KYLE, D. V. HOYT, and J. R. HICKEY / A Review of the Nimbus-7 ERB Solar Dataset 9 JUDIT M. PAP, RICHARD C. WILLSON, CLAUS FROHLICH, RICHARD F. DON- NELLY, and LARRY PUGA / Long-Term Variations in Total Solar Irradiance 13 1. ROMERO, C. WEHRLI, and C. FROHLICH / Solar Total Irradiance Variability from SOY A 2 on Board EURECA 23 YU. S. ROMANOV and N. S. ZGONY AIKO / The Periodicity of Solar Activity Cycles 31 C. 1. BUTLER / Maximum and Minimum Temperatures at Armagh Observatory, 1844-1992, and the Length of the Sunspot Cycle 35 E. A. GURTOVENKO, I. G. KESEL'MAN, R. I. KOSTYK, S. N. OSIPOV, N. I. LEBEDEV, I. M. KOPAYEV, V. N. ORAJEVSKY, and YU. D. ZHUGZHDA / Photometer "DIFOS" for the Study of Solar Brightness Variations 43 E. A. MAKAROV A, E. M. ROSHCHINA, and A. P. SARYCHEV / The Brightness of the Solar Disk in the Continuum in the Region 1.0-2.4 11m 47 MARKUS J. ASCHWANDEN / Irradiance Observations of the 1-8 A Solar Soft X-Ray Flux from GOES 53 M. T. DeLAND and R. P. CEBULA / Comparisons of the Mg II Index Products from the NOAA-9 and NOAA-II SBUV 12 Instruments 61 R. F. DONNELLY, O. R. WHITE, and W. C. LIVINGSTON / The Solar Ca II K Index and the Mg II Core-to-Wing Ratio 69 T. V. KAZACHEVSKAYA, A. I. LOMOVSKY, and A. A. NUSINOV / Solar EUV Flux Variations near Activity Maxima 77 B. C. MONSIGNORI FOSSI and M. LANDINI/The X-Ray-EUV Spectrum of Optically Thin Plasmas 81 E. I. TEREZ / List of Stars Recommended as Spectrophotometric Standards 87 L. EYER, M. GRENON, 1.-L. FALIN, M. FROESCHLE, and F. MIGNARD / Variable Stars with the Hipparcos Satellite 91 ALAN D. FIALA, DAVID W. DUNHAM, and SABATINO SOFIA / Variation of the Solar Diameterfrom Solar Eclipse Observations, 1715-1991 97 v vi TABLE OF CONTENTS RONALD 1. KROLL / Latitudinal Variation of the Solar Limb-Darkening Function 105 CLAUS FROHLICH, JUDIT M. PAP, and HUGH S. HUDSON / Improvement of the Photometric Sunspot Index and Changes of the Disk-Integrated Sunspot Contrast with Time 111 P. N. BRANDT, M. STIX, and H. WEINHARDT / Modelling Solar Irradiance Variations with an Area Dependent Photometric Sunspot Index 119 JUN NISHIKAWA / On the Cause of Total Irradiance Variations Observed by the CCD Solar Surface Photometer 125 R. MULLER and TH. ROUDIER / Latitude and Cycle Variations of the Photospheric Network 131 R. KARIY APPA and K. R. SIV ARAMAN / Variability of the Solar Chromospheric Network over the Solar Cycle 139 L. VAN DRIEL-GESZTELYI, H. S. HUDSON, B. ANWAR, and E. HIEI/ A Yohkoh Search for "Black-Light Flares" 145 M. RYBANSKY, V. RUSIN, M. MINAROVJECH, and P. GASPAR / Coronal Index of Solar Activity: Years 1939-1963 153 J. RYBAK / Rotational Characteristics of the Green Solar Corona: 1964-1989 161 E. J. SCHMAHL and M. R. KUNDU / Solar Cycle Variation of the Microwave Spectrum and Total Irradiance 167 V. G. NAGNIBEDA and V. V. PIOTROVITCH / Solar Brightness Distribution and Its Variability at 3 Millimeter Wavelength 175 M. GUHATHAKURTA and R. R. FISHER / Latitudinal Variability of Large-Scale Coronal Temperature and Its Association with the Density and the Global Magnetic Field 181 T. P. HARTSELL and P. L. BORNMANN / Active Region Evolution and Solar Flux Variations 189 E. A. MAKAROVA, T. V. KAZACHEVSKAYA, and A. V. KHARITONOV / On the Variability of Some Characteristics of Solar Radiative Flux 195 A, A. NUSINOV and V. V. KATYUSHINA / Lyman-Alpha Line Intensity as a Solar Activity Index in the Far Ultraviolet Range 201 W. KENT TOBISKA / Modeled Soft X-Ray Solar Irradiances 207 M. MINAROVJECH, V. RUSIN, and M. RYBANSKY / Cosmic Rays as an Indicator of Solar Activity 217 G. LUSTIG and H. WOHL / Meridional Motions of Sunspot Groups during Eleven Activity Cycles 221 TABLE OF CONTENTS vii 1. STAUDE, N. S. DZHALILOV, and Y. D. ZHUGZHDA / Radiation-Hydrodynamic Waves and Global Solar Oscillations 227 B. N. ANDERSEN / Excitation of Solar Gravity Waves 241 B. N. ANDERSEN, T. LEIFSEN, and T. TOUT AIN / Solar Noise Simulations in Irradiance 247 A. JIMENEZ, P. L. PALLE, C. REGULO, and T. ROC A CORTES / Secular Variations in the Spectrum of Solar P-Modes 253 REKHA JAIN and B. ROBERTS / Solar Cycle Variations in P-Modes and Chromospheric Magnetism 261 A. VIGOUROUX and PH. DELACHE / Sunspot Numbers Uncertainties and Parametric Representations of Solar Activity Variations 267 D. E. MKRTICHIAN / "Star as a Sun" Observations in Seismology of Distant Stars 275 KWING L. CHAN and HANS G. MA YR / Rotating Convection and the Solar Differential Rotation 283 V. P. BOBOVA and N. N. STEPANIAN / Variations of the Magnetic Fields of the Sun and the Earth within 7-50 Day Periods 291 T. BARANYI and A. LUDMANY / Distinction between the Climatic Effects of the Solar Corpuscular and Electromagnetic Radiation 297 L. PATERNO and S. SOFIA / EUDOSSO: A Space Project for Solar Oscillations and Long Term Variability Relevant to Climatic Changes 303 G. CINI CASTAGNOLI, G. BONINO, and C. TARICCO / Solar Magnetic and Bolometric Cycles Recorded in Sea Sediments 309 A. RUZMAIKIN, 1. FEYNMAN, and P. ROBINSON / Long-Term Persistence of Solar Activity (Abstract) 313 K. G. STRASSMEIER / Stellar Irradiance Variations Due to Surface Temperature In- homogeneities (Abstract) 314 G. DE TOMA, R. J. VERVACK, B. R. SANDEL, and R. STALIO / Voyager EUV Solar Spectra during 1981-1993 (Abstract) 315 N. AUDARD and J. PROVOST / On P-Mode Oscillations in Stars from 1M8 to 2M8 (Abstract) 316 M. STEINEGGER, H. HAUPT, P. N. BRANDT, and W. SCHMIDT / Facular Excess Radiation and the Energy Balance of Solar Active Regions (Abstract) 317 A. OZGOc; and T. ATAc; / The 73-Day Periodicity of the Flare Index during the Current Solar Cycle 22 (Abstract) 318 A. JIMENEZ / Phase Differences between Irradiance and Velocity Low Degree Solar Acoustic Modes Revisited (Abstract) 319 Preface The IAU Colloquium No. 143 "The Sun as a Variable Star: Solar and Stellar Irradiance Variations" was held on June 20 - 25, 1993 at the Clarion Harvest House, Boulder, Colorado, USA. The main objective of this Colloquium was to review the most recent results on the observations, theoretical interpreta­ tions, and empirical and physical models of the variations observed in solar and stellar irradiances. A special emphasis of the Colloquium was to discuss the results gained on the climatic impact of solar irradiance variability. The study of changes in solar and stellar irradiances has been of high interest for a long time. Determining the absolute value of the luminosity of stars with different ages is a crucial question for the theory of stellar evolu­ tion and energy production of stellar interiors. Observations of the temporal changes of solar and stellar irradiances - in the entire spectral band and at different wavelengths - provide an additional tool for studying the physical processes below the photosphere and in the solar- stellar atmospheres. Since the Sun's radiative output is the main driver of the physical processes with­ in the Earth's atmosphere, the study of irradiance changes is an extremely important issue for climatic studies as well. Climatic models show that small, but persistent changes in solar irradiance may influence the Earth's climate. Furthermore, to understand the human effect on global climatic change, the role of irradiance variations (as a significant source of natural climate changes) in terrestrial and climatic processes must be revealed. The Colloquium was a historical meeting since this was the first time when a conference sponsored by the International Astronomical Union was entirely devoted to irradiance variations and their climatic impact. 200 scien­ tists from 30 countries participated in this Colloquium. The Colloquium was divided into six sessions as defined by their key topics: (1) General Reviews on Observations of Solar and Stellar Irradiance Variability; (2) Observa­ tional Programs for Solar and Stellar Irradiance Variability; (3) Variabili­ ty of Solar and Stellar Irradiance Related to the Network, Active Regions (Sunspots and Plages), and Large-Scale Magnetic Structures; (4) Empiri­ cal Models of Solar Total and Spectral Irradiance Variability; (5) Solar and Stellar Oscillations, Irradiance Variations and their Interpretation; and (6) The Response of the Earth's Atmosphere to Solar Irradiance Variations and Sun-Climate Connections.
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