论文部分内容阅读
地磁规则日变化的有效提取能够提高地磁活动指数现报的准确性.本文基于1998—2013年北京十三陵(BMT)台站的地磁数据,利用卡尔曼滤波(KF)方法提取了地磁场规则日变化(S_R)曲线.该方法提取的S_R曲线具有明显的逐日变化特征,能够准确反映S_R曲线的季节变化和地方时效应.根据KF方法得到的S_R日变幅度逐日变化的结果,改进了K指数的量算方法,重新计算了十三陵台站的K指数以及Ak指数,并分析了S_R日变幅度的逐日变化对K指数量算的改进程度.分析结果表明,当K≤3时,KF方法可以较好地改善S_R曲线扰动幅度的计算,提高了地磁规则日变化提取的有效性,从而改进相应的地磁活动指数的量算.
The effective extraction of the daily variation of the geomagnetism rules can improve the accuracy of the report of the geomagnetism activity index.Based on the geomagnetic data of Beijing Ming Tombs (BMT) station from 1998 to 2013, the geomagnetic field rules are extracted by the Kalman filter (KF) method (S_R) curve.The S_R curve extracted by this method has obvious daily variation characteristics, and can accurately reflect the seasonal variation and local time effect of S_R curve.According to the daily variation of S_R curve obtained by KF method, K The K index and Ak index of Shisanling station were recalculated and the degree of improvement of K index calculated by the daily change of S_R diurnal variation was analyzed.The analysis results show that when K≤3, KF method can well improve the calculation of disturbance amplitude of S_R curve and improve the validity of diurnal variation of geomagnetism rules so as to improve the calculation of corresponding geomagnetic activity index.