Migrating tides and their variability are investigated using Canadian Middle Atmosphere Model (CMAM30) zonal and meridional wind data from 1979 to 2010. Migrating diurnal (DW1) and semi-diurnal (SW2) tides show strong annual and semi-annual variations. The former is stronger in the Southern Hemisphere and the latter is significant over sub-tropical latitudes in the mesosphere. Wavelet analysis in the mesopause region shows a 120-day variability in SW2 tide over equator and with no apparent connection with solar activity. A close inspection shows that the 120-day variation is not due to variations in solar energy inputs.

中文翻译：

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CMAM30 风迁移潮汐的 120 天变化

使用加拿大中层大气模型 (CMAM30) 1979 年至 2010 年的纬向和经向风数据研究了迁徙潮汐及其变化。迁徙日潮 (DW1) 和半日潮 (SW2) 潮汐显示出强烈的年度和半年度变化。前者在南半球较强，后者在中层亚热带纬度地区显着。中层顶区域的小波分析表明，赤道上空的 SW2 潮汐有 120 天的变化，与太阳活动没有明显的联系。仔细检查表明，120 天的变化并不是由于太阳能输入的变化造成的。