ANGEO Annales Geophysicae ANGEO Ann. Geophys. 1432-0576 Copernicus Publications Göttingen, Germany 10.5194/angeo-27-1625-2009 Characteristics of equatorial gravity waves derived from mesospheric airglow imaging observations Suzuki S. 1 Shiokawa K. 2 Liu A. Z. 3 Otsuka Y. 2 Ogawa T. 2 5 Nakamura T. 4 Sugadaira Space Radio Observatory, University of Electro-Communications, Chofu, Tokyo, Japan Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi, Japan Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto, Japan now at: National Institute of Information and Communications Technology, Koganei, Tokyo, Japan 06 04 2009 27 4 1625 1629 Copyright: © 2009 S. Suzuki et al. 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://angeo.copernicus.org/articles/27/1625/2009/angeo-27-1625-2009.html The full text article is available as a PDF file from https://angeo.copernicus.org/articles/27/1625/2009/angeo-27-1625-2009.pdf

We present the characteristics of small-scale (<100 km) gravity waves in the equatorial mesopause region derived from OH airglow imaging observations at Kototabang (100.3° E, 0.2° S), Indonesia, from 2002 to 2005. We adopted a method that could automatically detect gravity waves in the airglow images using two-dimensional cross power spectra of gravity waves. The propagation directions of the waves were likely controlled by zonal filtering due to stratospheric mean winds that show a quasi-biennial oscillation (QBO) and the presence of many wave sources in the troposphere.

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