Abstract A conspicuous and intermittent signature of a 120-day oscillation is found in the winds and tides in the mesosphere and lower thermosphere (MLT) over a Southern hemispheric equatorial station, Sao Joao do Cariri (7.4oS, 36.5oW) for the first time using meteor radar observations during the interval 2004–2008. The intermittent 120-day modulation can be as high as 10 m/s in the MLT winds. However, the seasonal component of the concerned periodicity, i.e. terannual oscillation is relatively smaller in amplitude (

中文翻译：

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São João do Cariri (7.4oS, 36.5oW) MLT 风和潮汐的 120 天振荡特征

摘要 在南半球赤道站 Sao Joao do Cariri (7.4oS, 36.5oW) 的中间层和低热层 (MLT) 的风和潮汐中首次发现了 120 天振荡的显着和间歇性特征在 2004-2008 年期间使用流星雷达观测。在 MLT 风中，间歇性 120 天调制可高达 10 m/s。然而，相关周期性的季节性成分，即年际振荡的幅度相对较小（