Baroclinic Wave Transitions in the Martian Atmosphere
Baroclinic Wave Transitions in the Martian Atmosphere
复制标题
火星大气中的斜压波转变
DOI：
10.1006/icar.1996.0055
复制
发表时间：
1996
期刊：
影响因子：
3.2
通讯作者：
F. Hourdin
中科院分区：
文献类型：
--
作者：
M. Collins;S. Lewis;P. Read;F. Hourdin
摘要利用奇异系统分析方法，对维京海盗号火星着陆器使命和火星大气GCM模拟的表面气压数据进行了分析。发现非常有规律的振荡，其频率呈双峰分布，峰值分别对应于约2-4天和5-7天的周期。两个振荡的振幅的重建通常是负相关的;即，当一个振荡的振幅大时，另一个振荡的振幅小。GCM模拟表明，两个振荡振幅的负相关可以解释为两个不同波数模式之间的翻转。在没有昼夜强迫的模式，过渡从一个不切实际的经常性的高频模式，以类似的不切实际的经常性的低频模式发生在北方冬季最多一次。然而，在模型中的昼夜周期，在非线性意义上的行为，以刺激两个波数之间的过渡，从而增加模式翻转事件的频率。相应的模拟结果与观测结果更为相似。
Abstract Surface pressure data from the Viking Lander mission and from GCM simulations of the martian atmosphere have been analyzed using singular systems analysis. Very regular oscillations are found with frequencies that are distributed bimodally with peaks corresponding to periods of approximately 2–4 days and 5–7 days, respectively. Reconstructions of the amplitudes of the two oscillations are often negatively correlated; i.e., when the amplitude of one oscillation is large, that of the other is small. The GCM simulations show that the negative correlation in the amplitudes of the two oscillations can be explained as a flipping between two different wavenumber modes. In the absence of diurnal forcing in the model, transition from an unrealistically regular high frequency mode to a similarly unrealistic regular low frequency mode occurs at most once during the northern winter season. The diurnal cycle in the model, however, acts in a non-linear sense to stimulate the transitions between the two wavenumbers and thus increases the frequency of mode flipping events. The corresponding simulations bear a closer resemblance to the observations.