【正文】 ng 100029, China2 Wuhan Institute of Physics and Mathematics, CAS, Wuhan 430071, China3 Graduate School of Chinese Academy of Sciences, Beijing, ChinaReceived: 8 May 2004 – Revised: 2 December 2004 – Accepted: 16 December 2004 – Published: 30 March 2005Abstract. The responses of Equatorial Ionization Anomaly (EIA) to the superstorms of October?November 2003 were investigated using the total electron content (TEC) measured with global positioning system (GPS) receivers in China, Southeast Asia, Australian (CSAA), and the American regions. Enhanced EIA was seen to be correlated with the southward turning of the interplanetary magnetic field Bz. In both the CSAA and American regions, EIA was intensified, corresponding to a large increase in the Flayer peak height (hmF2) measured by ionosonde and digisonde at middle and equatorial latitudes. However, the enhanced EIA was shown to be more significant during the daytime in the American region, which was associated with a series of large substorms when Bz was stable southward. The prompt penetration electric field and the wind disturbances dynamo electric field are suggested to be responsible for this observation according to current theory, although some features cannot be totally decipherable. Both the ionogram and magnetometer data show the existence of a weak shielding effect whose effect still needs further study. A clear asymmetric ionospheric response was shown in our TEC observations, even though it was only one month after autumnal equinox. The southern EIA crest was totally obliterated on 29 and 30 October in theCSAA region and on 31 October in the American region. Ion temperatures from the Defense Meteorological Satellite Program (DMSP) spacecraft revealed that the unequal energy injection at the polar region might be the reason for this effect. It is concluded that different physical processes have varying degrees of importance on the evolution of EIA in the CSAA and American regions. Keywords. Ionosphere (Equatorial ionosphere。 Accepted November 10, 2004)A newly installed meteor radar has been installed to measure winds in the mesosphere and lower thermosphere (MLT) over Wuhan (?E, ?N). In the present study, a database of the first 25 months (February 2002–February 2004) of observations has been analyzed to investigate the climatology of mean winds and tides. The daily average zonal wind is charactered by a strong shear in solstices and an intense eastward flow in summer. The daily average meridional wind is northward in winter and southward in other seasons. There are some discrepancies between the radar mean winds and the HWM93 model winds. The summer zonal winds and meridional winds from the model are obviously weaker than our observations. The analysis on tides indicates that the diurnal tide is dominant at Wuhan. The seasonal variability is observed in both the diurnal and semidiurnal tidal amplitudes with the maximum values occurring usually near the equinoxes. Compared with the Global Scale Wave Model (GSWM00), the observed results generally show a smaller diurnal tidal amplitude and a larger semidiurnal tidal amplitude. Key words: Meteor radar, mean winds, tides, MLT dynamics.The terdiurnal tide in the mesosphere and lower thermosphere over Wuhan (30?N, 114?E)Guangxin Zhao1,2,3, Libo Liu1, Baiqi Ning1, Weixing Wan1, and Jiangang Xiong1 1 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China2 Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China3 Graduate School of the Chinese Academy of Sciences, China(Received August 25, 2004。地磁與空間電磁環(huán)境研究室Seasonal behavior of meteor radar winds over WuhanGuangxin Zhao1,2,3, Libo Liu1, Weixing Wan1, Baiqi Ning1, and Jiangang Xiong11 Division of Geomagnetism and Space Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China2 Wuhan Institute of Physics and Mathematics, CAS, Wuhan, 430071, China3 Graduate School of the Chinese Academy of Sciences(Received March 23, 2004。 Revised November 9, 2004。 Revised April 18, 2005。 Ionospheremagnetosphere interactions。 received in revised form 18 August 2005。 1 lunar hour difference, with the eastward ponent leading the northward ponent for most months at Adelaide and eastward wind lagging the northward wind at Wuhan. Comparisons of phases between Wuhan and Adelaide suggest that an antisymmetric tide may be dominant in March, April, June and July and a symmetric tide in January, September and December. _ 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.Keywords: Lunar tides。 MesosphereThe 16day waves in the mesosphere and lower thermosphere over Wuhan (, ) and Adelaide (35_S, 138_E)Guoying Jianga,b,c, JianGang Xiong , WeiXing Wana, BaiQi Ninga,LiBo Liua, . Vincentd, I. Reida Institute of Geology and Geophysics, Chinese Academy of Sciences, . Box 9825, Beijing 100029, PR Chinab Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, . Box 71010, Wuhan 430071, PR Chinac Graduate School of Chinese Academy of Sciences, Beijing, PR Chinad Department of Physics and Mathematical Physics, University of Adelaide, Adelaide, SA, AustraliaReceived 14 October 2004。 accepted 2 March 2005Abstract Winds from a meteor radar at Wuhan (, ) and a MF radar at Adelaide (35_S, 138_E) are used to study the 16day waves in the mesosphere and lower thermosphere (MLT). The height range is 78–98 km at Wuhan and 70–98 km at Adelaide. By parison, it is found that the zonal ponents at both sites are generally larger than the meridional ones, and eastward motion of the zonal background winds is favorable for the 16day waves penetration to the MLT region. The zonal maximum amplitude appears in the autumn (September–October) around 86–98 km at Wuhan and in the winter months and early spring (July–October) around 72–82 km at Adelaide. Differences are found in wave amplitudes