Abstract The westward-propagating rotary wave-2 displacement field in the mantle with the period of 6 years ( Ding and Chao, 2018 ) predicts an ensuing 6-year variation in the Earth's two equatorial principle moments of inertia. In this paper we search for such signals in the sectoral Stokes coefficients C 22 and S 22 of the Earth's gravitational field. We analyze the monthly Δ C 22 and Δ S 22 data series derived from the satellite laser-ranging measurements for 1992-2018 (and the shorter series from the GRACE satellite, 2002-2017). We report unequivocal evidences found in Δ C 22 and Δ S 22 that conform to the predicted scenario in both amplitude and relative phasing. Conversely, this further corroborates the 6-year westward wave-2 motion in the Earth.

中文翻译：

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与地球向西旋转 6 年相关的赤道惯性矩的变化

摘要 地幔中6年周期向西传播的旋转波2位移场(Ding and Chao, 2018 )预测了地球两个赤道主惯性矩随后6年的变化。在本文中，我们在地球引力场的扇形斯托克斯系数 C 22 和 S 22 中搜索此类信号。我们分析了来自 1992-2018 年卫星激光测距测量（以及 2002-2017 年 GRACE 卫星的较短系列）的月度 Δ C 22 和 Δ S 22 数据系列。我们报告了在 Δ C 22 和 Δ S 22 中发现的明确证据，它们在幅度和相对相位方面都符合预测的情况。相反，这进一步证实了地球上 6 年的向西波 2 运动。