中低纬电离层多参数对震前异常电场响应的数值模拟  

Numerical Simulations of Mid-and Low-Latitude Ionospheric Response in Multiparameter to Anomalous Electric Fields Before Earthquakes

作　　者：胡艳莉[1] 徐彤[1] 朱庆林[1] 朱梦言 许正文[1] 吴健[1] HU Yanli;XU Tong;ZHU Qinglin;ZHU Mengyan;XU Zhengwen;WU Jian(National Key Laboratory of Electromagnetic Environment,China Research Institute of Radiowave Propagation,Qingdao 266107,Shandong,China)

机构地区：[1]中国电波传播研究所电波环境特性及模化技术重点实验室,山东青岛266107

出　　处：《武汉大学学报（理学版）》2020年第6期532-540,共9页Journal of Wuhan University:Natural Science Edition

基　　金：基础性军工科研院所稳定支持项目(A131901W10);泰山学者工程专项经费(ts20190968)。

摘　　要：电场驱动机制常用来解释震前电离层扰动现象。基于该理论,利用电离层物理模型SAMI2,模拟了电离层电子/离子密度(ne和ni)及温度(Te和Ti)等参数对电离层异常电场的响应。结果表明,mV/m量级的电离层异常水平电场可以导致与观测数据相当的电离层电子密度异常扰动,相对其他离子成分,O^+密度变化明显;扰动的空间分布与观测结果基本一致,扰动峰值点与震中投影点不重合,且震中两侧扰动相位不同,并存在"磁共轭"效应;异常电场方向不同,扰动相位的空间分布不同;电离层n_e与T_e扰动呈现负相关关系。模拟结果有助于全面认识震前电离层异常现象,加深对其机理的理解,为震前电离层异常的甄别提供理论支持。Electric field-driven mechanism is commonly used to explain ionospheric anomalies before earthquakes.Based on this theory,the ionospheric physical model SAMI2 is used to simulate the response of electron/ion density(n_e and n_i)and temperature(T_e and T_i)of the plasma to the ionospheric anomalous electric field.The results show that the ionospheric anomalous horizontal electric field of the order of mV/m can cause the abnormal disturbance of ionospheric electron density which is equivalent to the observed data.Compared with other ions,O^+density changes significantly.The spatial distribution of the disturbances is basically consistent with the observations.The peak perturbation point does not coincide with the epicenter and the deviation sign depends on the relative position.The disturbances also appear in the conjugated area of the opposite hemisphere.A change in the external electric field direction can lead to a change of the deviation sign.A negative correlation between ionospheric n_e and T_e is exhibited.The results help to further understand the characteristics and mechanisms of the seismo-ionospheric anomalies,and are of great significance for the identification of the seismo-ionospheric anomalies.

关 键 词：异常电场 电离层 异常扰动 数值模拟 

分 类 号：P315.7[天文地球—地震学]