ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-7-4943-2007 Evidence of gravity waves into the atmosphere during the March 2006 total solar eclipse Zerefos C. S. 1 3 Gerasopoulos E. 1 Tsagouri I. 1 Psiloglou B. E. 1 Belehaki A. 1 Herekakis T. 1 Bais A. 2 Kazadzis S. 2 Eleftheratos C. 3 Kalivitis N. 4 Mihalopoulos N. 4 National Observatory of Athens, V. Pavlou & I. Metaxa, P. Penteli, 15236, Athens, Greece Aristotle University of Thessaloniki, Physics Department, Laboratory of Atmospheric Physics, Thessaloniki, Greece Foundation for Biomedical Research, Academy of Athens, Greece University of Crete, Chemistry Department, Environmental and Chemical Processes Laboratory, Crete, Greece 26 09 2007 7 18 4943 4951 Copyright: © 2007 C. S. Zerefos et al. 2007 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://acp.copernicus.org/articles/7/4943/2007/acp-7-4943-2007.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/7/4943/2007/acp-7-4943-2007.pdf

This study aims at providing experimental evidence, to support the hypothesis according to which the movement of the moon's shadow sweeping the ozone layer at supersonic speed, during a solar eclipse, creates gravity waves in the atmosphere. An experiment was conducted to study eclipse induced thermal fluctuations in the ozone layer (via measurements of total ozone column, ozone photolysis rates and UV irradiance), the ionosphere (Ionosonde Total Electron Content – ITEC, peak electron density height – hmF2), and the troposphere (temperature, relative humidity), before, during and after the total solar eclipse of 29 March 2006. We found the existence of eclipse induced dominant oscillations in the parameters related to the ozone layer and the ionosphere, with periods ranging between 30–40 min. Cross-spectrum analyses resulted to statistically significant square coherences between the observed oscillations, strengthening thermal stratospheric ozone forcing as the main mechanism for GWs. Additional support for a source below the ionosphere was provided by the amplitude of the oscillations in the ionospheric electron density, which increased upwards from 160 to 220 km height. Even though similar oscillations were shown in surface temperature and relative humidity data, no clear evidence for tropospheric influence could be derived from this study, due to the modest amplitude of these waves and the manifold rationale inside the boundary layer.

 References Altadill, D., Sole, J. G., and Apostolov, E. M.: Vertical structure of a gravity wave like oscillation in the ionosphere generated by the solar eclipse of August 11, 1999, J. Geophys. Res., 106(A10), 21 419–21 428, 2001. Anderson, R. C., Keefer, D. R., and Myers, O. E.: Atmospheric pressure and temperature changes during the 7 March 1970 solar eclipse, J. Atmos. Sci., 29, 583–587, 1972. Bais, A. F., Zerefos, C. S., and McElroy, C. T.: Solar UVB measurements with the double and single monochromator Brewer ozone spectroradiometers, Geophys. Res. Lett., 23, 833–836, 1996. Blumthaler, M., Bais, A., Webb, A., Kazadzis, S., Kift, R., Kouremeti, N., Schallhart, B., Kazantzidis, A.: Variations of solar radiation at the Earth's surface during the total solar eclipse of 29 March 2006, in: Remote Sensing of Clouds and the Atmosphere XI, edited by: Slusser, J. R., Schäfer, K., Comerón, A., Proceedings of the SPIE, Vol 6362, https://doi.org/10.1117/12.689630, 2006. Chimonas, G.: Internal gravity-waves motions induced in the Earth's atmosphere by a solar eclipse, J. Geophys. Res., 75, 5545–5551, 1970. Chimonas, G.: Lamb waves generated by the 1970 solar eclipse, Planetary Space Science, 21, 1843–1854, 1973. Chimonas, G. and Hines, C. O.: Atmospheric gravity waves induced by a solar eclipse, J. Geophys. Res., 75, p. 875, 1970. Chimonas, G. and Hines, C. O.: Atmospheric gravity waves induced by a solar eclipse, 2, J. Geophys. Res., 76(28), 7003–7005, 1971. Davis, M. J. and da Rosa, A. V.: Possible detection of atmospheric gravity waves generated by the solar eclipse, Nature, 226, p. 1123, 1970. Dörnbrack, A., Birner, T., Fix, A., Flentje, H., Meister, A., Schmid, H., Browell, E. V., and Mahoney, M. J.: Evidence for inertia gravity waves forming polar stratospheric clouds over Scandinavia, J. Geophys. Res., 107(D20), 8287, https://doi.org/10.1029/2001JD000452, 2002. Eckermann, S. D., Broutman, D., Stollberg, M. T., Ma, J., McCormack, J. P., and Hogan, T. F.: Atmospheric effects of the total solar eclipse of 4 December 2002 simulated with a high-altitude global Model, J. Geophys. Res., 112, D14105, https://doi.org/10.1029/2006JD007880, 2007. Founda, D., Melas, D., Lykoudis, S., Lysaridis, I., Kouvarakis, G., and Petrakis, M.: The effect of the total solar eclipse of March 29, 2006 on meteorological variables in Greece, Atmos. Chem. Phys. Discuss., 7, 10 631–10 667, 2007. Fritts, D. C. and Luo, Z.: Gravity wave forcing in the middle atmosphere due to reduced ozone heating during a solar eclipse, J. Geophys. Res., 98(D2), 3011–3021, 1993. Fritts, D. C. and Alexander, M. J.: Gravity wave dynamics and effects in the middle atmosphere, Rev. Geophys., 41(1), 1003, https://doi.org/10.1029/2001RG000106, 2003. Gerasopoulos, E., Kouvarakis, G., Vrekoussis, M., Donoussis, C., Kanakidou, M., and Mihalopoulos, N.: Photochemical ozone production in the Eastern Mediterranean, Atmos. Environ., 40, 3057–3069, https://doi.org/10.1016/j.atmosenv.2005.12.061, 2006. Hanuise, C., Broche, P., and Ogubazghi, G.: HF Doppler observations of gravity waves during the 16 February 1980 solar eclipse, J. Atmos. Solar-Terr. Phys., 44, 963–966, 1982. Hays, P. B., Kafkalidis, J. F., Skinner, W. R., and Roble, R. G.: A global view of the molecular oxygen night glow, J. Geophys. Res.-Atmos., 108(D20), 4646, https://doi.org/10.1029/2003JD003400, 2003. Jones, B. W.: A search for atmospheric pressure waves from the total solar eclipse of 9 March 1997, J. Atmos. Solar-Terr. Phys., 61, 1017–1024, 1999. Kazadzis, S., Topaloglou, C., Bais, A. F., Blumthaler, M., Balis, D., Kazantzidis, A., and Schallhart, B.: Actinic flux and O$^1$D photolysis frequencies retrieved from spectral measurements of irradiance at Thessaloniki, Greece, Atmos. Chem. Phys., 4, 2215–2226, 2004. Kazadzis, S., Bais, A., Kouremeti, N., Blumthaler, M., Webb, A., Kift, R., Schallhart, B., and Kazantzidis, A.: Effects of total solar eclipse of 29 March 2006 on surface radiation, Atmos. Chem. Phys. Discuss., 7, 9235–9258, 2007. Kazantzidis, A., Bais, A. F., Emde, C., Kazadzis, S. and Zerefos, C. S.: Attenuation of global ultraviolet and visible irradiance over Greece during the total solar eclipse of 29 March 2006, Atmos. Chem. Phys. Discuss., 7, 13475–13501, 2007. Liu, J. Y., Hsiao, C. C., Tsai, L. C., Liu, C. H., Kuo, F. S., Lue, H. Y., and Huang, C. M.: Vertical phase and group velocities of internal gravity waves from ionograms during the solar eclipse of 24 October 1995, J. Atmos. Solar-Terr. Phys., 60, 1679–1686, 1998. Mapes, B. E.: Gregarious tropical convection, J. Atmos. Sci., 50, 2026–2037, 1993. Mayaud, P. N.: Derivation, Meaning and Use of Geomagnetic Indices, AGU Geophysical Monograph, 22, Washington D.C., 1980. Mims III, F. M. and Mims, E. R.: Fluctuations in column ozone during the total solar eclipse of July 11, 1991, Geophys. Res. Lett., 20(5), 367–370, 1993. Müller-Wodarg, I. C. F., Aylward, A. D., and Lockwood, M.: Effects of a mid-latitude solar eclipse on the thermosphere and ionosphere: A modelling study, Geophys. Res. Lett., 25, 3787–3790, 1998. Prölss, G. W.: Ionospheric F-region storms in Handbook of Atmospheric Electrodynamics, II, , 195–248, CRC Press, 1995. Ridley, E. C., Dickinson, R. E., Roble, R. G., and Rees, M. H.: Thermospheric response to the June 11, 1983, solar eclipse, J. Geophys. Res., 89, 7583–7588, 1984. Roble, R. G., Emery, B. A., and Ridley, E. C.: Ionospheric and thermospheric response over Millstone Hill to the May 30, 1984 annular solar eclipse, J. Geophys. Res., 91, 1661–1670, 1986. Ruggaber, A., Dlugi, R., and Nakajima, T.: Modelling Radiation Quantities and Photolysis Frequencies in the Troposphere, J. Atmos. Chem., 18, 171–210, 1994. Sauli, P., Abry, P., Boska, J., and Duchayne, L.: Wavelet characterization of ionospheric acoustic and gravity waves occurring during the solar eclipse of August 11, 1999, J. Atmos. Solar-Terr. Phys., 68, 586–598, 2006. Seykora, E. J., Bhatnagar, A., Jain, R. M., and Streete, J. L.: Evidence of atmospheric gravity waves produced during the 11 June 1983 total solar eclipse, Nature, 313, 124–125, 1985. Singh, L., Tyagi, T. R., Somayajulu, Y. V., Vijayakumar, P. N., Dabas, R. S., Loganadham, B., Ramakrishna, S., Rama Rao, P. V. S., Dasgupta, A., Naneeth, G., Klobuchar, J. A., and Hartmann, G. K.: A multi-station satellite radio beacon study of ionospheric variations during solar eclipses, J. Atmos. Solar-Terr. Phys., 51, 271–278, 1989. Voigt, C., Tsias, A., Dörnbrack, A, Meilinger, S., Luo, B., Schreiner, J., Larsen, N., Mauersberger, K., and Peter, T.: Non-equilibrium compositions of polar stratospheric clouds in gravity waves, Geophys. Res. Lett., 27(23), 3873–3876, 2000. Zerefos, C. S., Balis, D. S., Meleti, C., Bais, A. F., Tourpali, K., Kourtidis, K., Vanicek, K., Cappellani, F., Kaminski, U., Colombo, T., Stubi, R., Manea, L., Formenti, P., and Andreae M. O.: Changes in surface solar UV irradiances and total ozone during the solar eclipse of August 11, 1999, J. Geophys. Res., 105(D21), 26 463–26 473, 2000.