Quasi-biennial oscillation influence on long-period planetary waves in the Antarctic upper mesosphere
Quasi-biennial oscillation influence on long-period planetary waves in the Antarctic upper mesosphere
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准两年期振荡对南极上层中间层长周期行星波的影响
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
E. Ford
中科院分区：
文献类型：
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作者：
R. Hibbins;M. Jarvis;E. Ford
[1] 展示了利用南极哈雷 SuperDARN 雷达在 12 年期间记录的流星风观测得出的长周期行星波数据，并将其与整个赤道平流层的准两年期振荡 (QBO) 的相位进行了比较。南极上层中间层的行星波活动增强出现在夏季，此时赤道上平流层的 QBO 为西风，而在冬末，此时上平流层的 QBO 为东风。行星波活动每两年一次的增强与南极上层中层冬末东风强度的减少（高达 30%）同时发生。此外，当 QBO 处于哈雷上方中间层上层行星波活动增强的正确相位时，在北半球高纬度上层中间层测量到的行星波活动会减少（反之亦然）。这些结果清楚地表明行星波从冬季半球到夏季半球的显着的半球间传播。根据这些结果，讨论了平流层 QBO 在赤道上层中间层诱发足够强的 QBO 来充当这些长周期波在半球间传播的大门的观测证据。
[1] Long-period planetary wave data derived from meteor wind observations recorded over a 12-year period with the SuperDARN radar at Halley, Antarctica, are presented and compared with the phase of the quasi-biennial oscillation (QBO) throughout the equatorial stratosphere. Enhanced planetary wave activity in the Antarctic upper mesosphere is found during the summer months, when the QBO in the equatorial upper stratosphere is westerly, and during the late winter, when the QBO in the upper stratosphere is easterly. These quasi-biennial enhancements in planetary wave activity coincide with a reduction in strength, by up to 30%, of the late-winter eastward winds in the Antarctic upper mesosphere. In addition, when the QBO is in the correct phase for enhanced planetary wave activity in the upper mesosphere above Halley, planetary wave activity measured in the upper mesosphere of the high-latitude Northern Hemisphere is reduced (and vice versa). These results clearly indicate significant interhemispheric propagation of planetary waves from the winter to summer hemispheres. Observational evidence that the stratospheric QBO induces a strong enough QBO in the equatorial upper mesosphere to act as a gate to the interhemispheric propagation of these long-period waves is discussed in light of these results.