基于地球流体有效角动量函数的UT1分段预报  

Piecewise UT1 prediction based on the Earth’s fluid effective angular momentum function

作　　者：杨新宇 吴元伟 赵鑫 杨旭海[1,2] 张首刚 YANG Xin-yu;WU Yuan-wei;ZHAO Xin;YANG Xu-hai;ZHANG Shou-gang(National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Electronic Electrical and Communication Engineering,Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家授时中心,西安710600 [2]中国科学院大学,北京100049 [3]中国科学院大学电子电气与通信工程学院,北京100049

出　　处：《时间频率学报》2023年第2期94-104,共11页Journal of Time and Frequency

基　　金：中国科学院“一带一路”资助项目(XAB2018YDYL01);国家自然科学基金面上资助项目(12073034)。

摘　　要：世界时UT1的变化受到大气、海洋、陆地水圈等多种激发因素的影响,这些激发因素可以由地球流体有效角动量函数EAM(effective angular momentum)描述。基于德国地学研究中心地球系统建模小组ESMGFZ(Earth System Modeling at GeoForschungsZentrum)的有效角动量函数和国际地球自转和参考系服务IERS(International Earth Rotation and Reference Systems Service)的EOP(Earth orientation parameters)数据,使用最小二乘法LS(least square)和自回归模型AR(auto regression)方法,通过一系列实验,参数搜索,最终,针对不同的预报跨度,采用不同的参数对世界时UT1进行预报。在2019年至2021年进行的495次预报实验中,对比IERS的预报结果,在未来第6天,第30天,第90天,平均绝对误差MAE(mean absolute error)分别降低了0.0874 ms,0.4999 ms,1.4764 ms,提升分别为37.43%、14.72%、11.82%;对比传统LS+AR的预报结果,在未来第6天,第30天,第90天,MAE分别降低了0.6315 ms,1.1347 ms,2.3761 ms,提升分别为81.21%、28.15%、17.74%。The variation of UT1 is affected by the excitations of atmosphere,ocean and terrestrial hydrosphere.These excitations can be described by the effective angular momentum function EAM(effective angular momentum)of the Earth’s fluid components.A series of UT1 prediction experiments are performed by combining the GFZ(GeoForschungsZentrum)EAM data and the IERS(International Earth Rotation and Reference Systems Service)UT1 C04 series and using the LS(least square)and AR(auto regression)method.The UT1 was predicted in 90 days by adopting different parameters in different time spans.For the 495 prediction experiments with date ranging from 2019 to 2021,compared with the IERS Bulletin A prediction,the MAE(mean absolute error)is reduced by 0.0874 ms,0.4999 ms and 1.4764 ms respectively on the 6th,30th and 90th day in the future,corresponding to an improvement of 37.43%,14.72%and 11.82%respectively;Compared with the prediction results of traditional LS+AR method,the MAE is reduced by 0.6315 ms,1.1347 ms and 2.3761 ms respectively on the 6th,30th and 90th day in the future,corresponding to an improvement of 81.21%,28.15% and 17.74% respectively.

关 键 词：地球自转 UT1预报 地球流体有效角动量函数 

分 类 号：P128[天文地球—天体测量] P183.31[天文地球—天文学]