日长变化与地磁场变化的时滞相关分析

Analysis on the Time-lag Correlation for the Changes of the Length of the Day and Geomagnetic Field

利用历史地磁场模型资料和日长资料,计算和分析了1840-2000年期间地磁场变化与日长变化的互相关特点。结果表明,地磁变化与日长变化存在时滞相关。地磁场强度参数的变化比日长变化超前7.5-10a（年）;地磁场西向漂移参数比日长变化滞后,其中,西漂分量.λ2^1和 λ3^2滞后7.5a,而地磁场的平均漂移速度和纬度漂移分量滞后20-22.5a。

Two data sets including the historical geomagnetic field model and the length of the day are used to anaiyze the correlation Characteristics of the geomagnetic field variation and the changes in the length of the day from 1840 - 2000. The results show that a lag correlation is available in the changes of geomagnetic field and the length of the day. The geomagnetic intensity parameter is approximately exceeding LOD by 7.5 - 10a （year）. However the geomagnetic western drift parameters lag behind LOD variation, the western drift components λ2^1 and λ3^2 lag behind LOD by 7.5a, the average drifting speed and the latitudinal drifting components of the geomagnetic field lag behind LOD by 20-22.5a.