经验和抛物面模式模拟暴时磁场的误差特性研究  

Error characteristics of the empirical and paraboloid magnetic field models during storms

作　　者：张晓芳[1] 符养 严卫[1] 

机构地区：[1]中国人民解放军理工大学气象学院,中国南京211101 [2]北京应用气象研究所,中国北京100029

出　　处：《地震地磁观测与研究》2008年第2期34-41,共8页Seismological and Geomagnetic Observation and Research

摘　　要：利用两种不同的磁场模式,协同GOES10/12、Polar及Geotail的实测资料,本文对3种不同强度磁暴的磁层磁场进行了详细分析,从而检验了两种不同磁场模式的可靠性,给出了模式间的性能对比。我们采用Tsyganenko经验模式及Alexeev抛物面模式,分别模拟了2004年4月、7月和11月的磁暴,3个磁暴过程中最强Dst指数分别达到-110nT,-150nT以及-289nT。结果发现:T01模式对于中等磁暴时磁场模拟准确,而由于建立模式的数据库中强磁暴资料少,模式中不包含亚暴效应,T01对于强磁暴磁场模拟的误差增大,磁场分量远远偏离观测值;A2000模式缺少部分环电流及Ⅱ区场向电流,模式对于近地点Polar轨道上的磁场扰动模拟不足,对强磁暴时亚暴效应的过高模拟使其模拟的磁场分量偏高;T01模式对于中等磁暴时磁场的模拟效果明显好于A2000模式,随着磁层扰动的增强,T01与A2000模式的总体性能相当。In this paper, the reliability of the three models is contrasted and examined by comparing the magnetospheric magnetic fields modeled by the empirical models T96.T01 and the parab- oloid model A2000 with observations from GOES10/12, Polar and Geotail satellites. We have modeled three storm events, one on 3 ～4 April 2004 when the Dst index reached -110 nT, one on 24～26 July 2004 when Dst reached -150 nT, and another on 9～11 Novemberwhen Dst dropped -289 nT. The results show that, the T01 model shows good agreement with observations during moderate storm. Since the substorm effect is not included in the T01 model and intense storms are only a small part of the databases that construct the model, the magnetic field modeled by T01 shows more deviation from observations during intense storms. Due to the absence of partial ring current and II region field-aligned current, the A2000 model underestimates the disturbance of magnetic filed component observed by Polar near perigees. And due to overestimation for the substorm effect during intense storms, the Bx magnetic filed component modeled by A2000 is much larger than observations. Summarily, the T01 model shows better agreement with observation than that of the A2000 model for moderate storm event, while errors of the two models are comparable for the intense storms.

关 键 词：磁暴 亚暴 磁层磁场 Tsyganenko模式 抛物面模式 

分 类 号：P353[天文地球—空间物理学]