利用球冠谐分析法对2009年我国35个绝对观测地磁台站的sq太阳静日变化进行内外源场分离,反演得到三个劳埃德季节(冬季D,分点E,夏季J)相应的内、外源等效电流体系,结果表明sq外源电流体系在该区域D、E、J三个季节的电流涡中心强度分别为56.2kA、137.7kA、137.9kA,电流涡中心位置的地方时由冬季的1124LT前移至夏季的约1030LT;Sq内源电流体系在该区域D、E、J三个季节的电流涡中心强度分别为21.1kA、63.4kA、72.7kA,电流涡中心位置的地方时由冬季的1100LT前移至夏季的约1000LT.
We calculated three-component Sq variations of 35 geomagnetic observatories for three geomagnetic seasons in China in 2009, and used spherical cap harmonic analyzing method to divide those Sq variations into inner and external two parts, then deduced their equivalent current system individually. We analyzed the seasonal characteristics of the two parts of geomagnetic current systems and obtained the following results. For external current system, in three Lloyd(D,E,J) seasons, respectively, the maximum intensity is 56.2 kA, 137.7 kA, 137.9 kA, and the LT of the current vortex is displaced from l124LT to about 1030 LT. For inner current system, in D, E, J season, respectively, the maximum intensity is 21.1 kA, 63.4 kA, 72.7 kA, and the LT of the current vortex is displaced from 1100 LT to about 1000 LT.