Zonally non‐uniform distribution of equatorial gravity waves in an atmospheric general circulation model
Zonally non‐uniform distribution of equatorial gravity waves in an atmospheric general circulation model
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DOI：
10.1029/2005gl024068
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发表时间：
2005-12
影响因子：
5.2
通讯作者：
Y. Kawatani;K. Tsuji;M. Takahashi
中科院分区：
文献类型：
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作者：
Y. Kawatani;K. Tsuji;M. Takahashi
没有重力波（GW）阻力参数化的大气环流模式的结果包括赤道平流层下部的准两年振荡（QBO）样振荡。分析了QBO西风切变位相期间赤道地区周期小于3天的重力波的纬向分布。QBO的西风加速与纬向强迫有关，而纬向强迫是由各分量的分解波引起的，全球变暖约占强迫的60%。对流层上层大气纬向动量的垂直通量呈非均匀分布。东（西）半球主要是大（相对较小）量级的上升通量和西风（东风）动量。波动量通量散度也随经度变化。在东半球，由全球变暖引起的纬向风的西风加速比西半球大得多。
The results from an atmospheric general circulation model without gravity wave (GW) drag parameterization include quasi‐biennial oscillation (QBO)‐like oscillations in the equatorial lower stratosphere. The zonal distribution of gravity waves with periods of less than 3 days over the equatorial region is analyzed for 2 months (July–August) during the westerly shear phase of the QBO. The westerly acceleration of the QBO is associated with the zonal forcing due to resolved waves of all components, and GWs account for about 60% of the forcing. The vertical flux of the zonal momentum of GWs in the upper troposphere has a non‐uniform distribution. Large (relatively small) magnitude upward fluxes with westerly (easterly) momentum dominate in the Eastern (Western) Hemisphere. The wave momentum flux divergence also varies with longitude. The westerly acceleration of the zonal wind due to GWs in the Eastern Hemisphere is much greater than that in the Western Hemisphere.