【摘要】 近年来地球自转加速现象引起时间保持领域的特别关注。利用国际地球自转和参考服务（IERS）提供的1972—2023年地球定向参数序列EOP C04数据，定位到最近的一次日长变化?LOD的拐点发生时间在2015—2016年间。本文针对地球自转加速是否会导致?LOD序列的中短周期项发生改变这一问题开展研究，采用了经验模态分解和快速傅里叶变换方法对拐点前后?LOD序列的中短周期项及其误差进行了细致的比较分析。数据分析表明，在目前数据和周期分析工具的精度水平上，未探测到由于地球自转加速导致的?LOD数据9.131,13.666,27.566,182.625和365.250 d周期成分的周期改变。更多还原

【Abstract】 The acceleration of the Earth’s rotation has received special attention in recent years, especially in the time keeping community. With the 1972-2023 Earth orientation parameter sequence EOP C04 data provided by the International Earth Rotation and Reference Service(IERS), we noticed an inflection point of ?LOD between 2015 and 2016. To answer the question of whether the speed up of the Earth rotation can influence the period of the ?LOD series, we make comparisons of the periods to the ?LOD data before and after the inflection point with the methods of ensemble empirical mode decomposition, and fast Fourier transforms.On the accuracy level of our methods, our analysis can not detect significant periodic changes for the 9.131,13.666, 27.566, 182.625 and 365.250 days components of ?LOD data.更多还原