大气对地球自转参数（ERP）的高频激发

HIGH FREQUENCY EXCITATION OF EARTH ROTATION PARAMETERS (ERP) FROM ATMOSPHERE

本文采用１９８３—１９９２年期间由空间大地测量技术观测和归算的地球自转参数（ＥＲＰ）序列，以及由全球气象资料归算的大气角动量（ＡＡＭ）序列，分析和研究了大气对地球自转参数的日长变化（ＬＯＤ）和极移（ｘ和ｙ）在一个月时间尺度以内的高频激发作用，得到的主要结果如下：１大气对ＬＯＤ分量高频潮汐的估计值存在着影响，但是，潮汐形变参数ｋ／ｃ随时间和频率的变化却是受非大气因素的扰动引起的．２．大气可以解释３０天以下ＬＯＤ非潮汐的大部分变化．３．极移分量３０天以内的高频变化也主要由大气激发．ｘ分量与大气的相关性要强于ｙ分量，而且更为稳定，主要表现为平均时间尺度约为２７天的波动，大气对这个波动的贡献可达７０％．

The data sets of Earth Rotation Parameters (ERP) measured by the spacegeodetic techniques and atmospheric angular momentum (AAM) reduced by the globalmeteorological data from 1983 through 1992 are used in this work to analyse andstudy the high frequency excitations of Earth rotation parameters for the length ofday (LOD) and polar motion (X and Y components) up to the monthly time scalefrom atmosphere. The main results are as follows:1. The effects of atmosphere on tile estimated values of high frequency tides forLOD component are exicted. K /C of tidal deformation parameters is changed withthe time and frequency, and induced by non-atmospheric disturbances.2. The atmosphere may explain the greater part of non-tide high frequency variation in LOD up to 30 days.3. The high frequency variations of polar motion up to 30 days are mathly excited by the atmosphere. The relationship between the X component and atmosphereis better and more stable than that between the Y component and atmosphere. It isshown that there is a fluctuation in the X component with the mean time scale ofabout 27 days and the contribution of atmosphere of the fluctuation is about 70%.