2019-05-26秘鲁北部地震前低纬电离层变化分析北大核心CSCD

针对2019-05-26秘鲁北部M W8.0地震,利用CODE-TEC数据和GPS-TEC实测数据,分析此次地震前上空电离层总电子含量和电离层赤道异常变化。利用地震前2019-05-10~26总电子含量格网数据分析震前电离层赤道异常变化和电离层TEC随地理纬度的异常变化;然后利用RIOP和GLPS站的GPS-TEC数据,统计分析地震前电离层TEC日变化异常。结果表明,地震发生前3 d,电离层赤道异常“双峰”消失,且电离层TEC含量显著减少,可达10 TECu左右。在地震发生前3 d 16:00~20:00 UT,电离层TEC随纬度变化呈现双峰曲线特征,震中附近存在低谷,且在该期间RIOP和GLPS站电离层TEC也出现显著减少现象。

Analysis of Low Latitude Ionospheric Changes before the May 26, 2019 Earthquake in Northern Peru

Based on the M_W8.0 earthquake in northern Peru on May 26, 2019, using the global ionospheric map(GIM) obtained by the center for orbit determination in Europe(CODE) and the GPS-TEC observation data provided by the international GNSS service, we analyze the changes of ionosphere total electron content(TEC) and equatorial ionospheric anomaly before the earthquake. Using the TEC grid data from May 10 to 26, 2019, we analyze the variation of equatorial ionospheric anomaly and ionospheric TEC with geographic latitude before the earthquake, and statistically analyze the daily variation anomalies of ionospheric TEC before the earthquake using the GPS-TEC data of RIOP and GLPS stations. The results show that three days before the earthquake, the equatorial ionospheric anomaly “double peaks” disappeared, and the ionospheric TEC decreased significantly, reaching about 10 TECu. At 16:00~20:00 UT three days before the earthquake, the ionospheric TEC shows a bimodal curve with latitude, and there is a trough near the epicenter. During this period, the ionospheric TEC at RIOP and GLPS stations also decreased significantly.