太阳耀斑对电离层天顶方向电子总量的影响

ON EFFECT OF SOLAR FLARE ON VERTICAL TOTAL ELECTRIC CONTENTS IN IONOSPHERIC

对 2 0 0 0年 7月 14日太阳耀斑爆发期间北京、武汉、上海 3个观测站的GPS数据进行了精化处理 ,计算出各个卫星交叉点沿天顶方向上的电子总量 ,并对是否消除仪器偏差的计算结果进行了比较 ,从时间域、空间域上分析了这次耀斑爆发时电离层电子总量变化的特点。结果表明 :利用精化的GPS数据才能更好地反映出太阳耀斑爆发时电离层电子总量的突变情况和变化规律。分析 1998年 11月 2 2日和 2 0 0 0年 7月 14日耀斑爆发期间的GPS资料 ,还发现在耀斑爆发前一天与耀斑爆发相对应的一个时间段内 ,如果卫星交叉点的运动轨迹是从高纬到低纬的运动 ,这些交叉点的VTEC(天顶方向上的电子总量 )值在该时间段内有迅速增长的异常现象。这是否是耀斑爆发的“前兆”现象 。

The GPS data of Beijing, Wuhan, Shanghai station during the solar flare burst on July 14, 2000 is dealt with in this paper. The vertical total electric contents (VTEC) of every ionospheric pierce point (IPP) are calculated,and the result with the instrumental bias is compared with the result without the instrumental bias. The characteristics of the TEC of the ionosphere in space and time domain while the flare burst is analyzed. The analysis shows that only when the precise GPS data is used,the sudden increase and the change rule of VTEC during the flare burst can be reflected better. Analysis of the GPS data during the flare burst on Nov. 22, 1998 and Jul. 14, 2000, shows that if these IPPs move from the high latitude to the low latitude, the IPP's VTEC increases quickly in the corresponding time on the day before the flare burst.Whether this abnormal phenomenon is the 'auspice' of the flare burst,it is worth studying further.