Satellite observations show that there is a wintertime hotspot of gravity wave activity, located mainly over the ocean, around 60°S in the stratosphere. However, the sources of the gravity waves making up this hotspot are varied and complex and remain unclear. Here we use radiosonde observations from 11 Antarctic stations and selected small islands close to 60°S to examine the horizontal directional pseudo‐momentum flux and energy density distributions of upward propagating gravity waves in the lower stratosphere. This paper shows, for the first time, that short vertical wavelength gravity waves in the lower stratosphere clearly propagate meridionally toward 60°S during the winter months. This result supports previous studies that show that this belt of gravity wave activity over the ocean is contributed to by wave sources outside 60°S.

中文翻译：

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平流层下部60°S附近重力波冬季经向收敛的无线电探空仪观测

卫星观测表明，冬季有一个重力波活动的热点，主要集中在平流层大约60°S的海洋上空。但是，构成这个热点的重力波的来源是多种多样且复杂的，仍然不清楚。在这里，我们使用来自11个南极站和选定的接近60°S的小岛的探空仪观测数据，来检查平流层下部向上传播的重力波的水平方向伪动量通量和能量密度分布。本文首次表明，在冬季，平流层下部的短垂直波长重力波清楚地向60°S子午经传播。这一结果支持了先前的研究，这些研究表明，海洋上空的重力波活动带是由60°S以外的波源造成的。