利用法国电磁卫星Demeter装载的ICE(电场探针)及IAP(等离子体分析仪)探测数据,分析研究2006年不同季节、不同地方时顶部电离层电场及各等离子参量的全球空间分布特征,结果发现,电场x分量及H+离子浓度、O+离子浓度、He+离子浓度、等离子体温度具有显著的季节变化和地方时变化,而电场了分量及z分量全球分布的季节和地方时效应不明显。可见,在分析地震引起的电离层异常时,需要排除电场x分量、H+离子浓度、O+离子浓度、He+离子浓度、等离子体温度这些显著的季节和地方时变化。
Kinds of variations in the ionosphere cover the possible abnormal induced by transient accidents (such as earthquake), so itls necessary of the studies on characteristics of these variations for the exploring to seismic-ionosphere coupling phenomena. Here, we use observations of the instruments ICE (Instrument Champ Electrics) and IAP (Instrument Analyzer of Plasma) onboard Demeter electro-magnetic micro-satellite to analyze the spatial distributions of ionospheric electric field and ions parameters in 2006. As the result, we conclude that there are obvious seasonal variations and local time variations of the Ex vector and H+ density. O+ density. He+ density and ions temperature, by contraries, seasonal and local-time effects of the electric-wave Ey and Ez vector are not apparent. Based on the definition that the long term global graphs of one season (include longer time period) compared to the transient earthquake event are called background fields of the ionosphere. We can conclude that the seasonal and local time variations of the electric-wave Ex vector and H+ density. O+ density. He+ density, ions temperature must be subtracted while extracting the Seismic-ionospheric disturbances.