基于CHAMP卫星与三维Taylor多项式模型的区域地磁建模研究  

Regional geomagnetic modelling based on the magnetic data of CHAMP satellite and 3D Taylor polynomial

作　　者：蒋勇[1,2] 姜乙 冯彦[1,2] 刘宝嘉 傅帅[1] 常德[1] 张鹏飞[1] 江涛[1] 

机构地区：[1]南京信息工程大学空间天气研究所,南京210044 [2]中国科学院空间天气学国家重点实验室,北京100190

出　　处：《地球物理学报》2015年第9期3121-3132,共12页Chinese Journal of Geophysics

基　　金：国家自然科学基金(41404053;41174165);公益性行业(气象)科研专项(GYHY201306073);江苏省高校自然科学研究基金(14KJB170012);大学生创新创业训练计划项目基金联合资助

摘　　要：利用CHAMP卫星矢量和标量地磁测量数据,通过三维Taylor多项式模型建立了2010.0年中国及邻近地区在300km高度附近的X、Y、Z和F分量的三维磁场模型.为了比较验证所建模型,分析了其与Taylor多项式模型(二维模型)不同截断阶数所对应的均方偏差(RMSE)、残差及分布等.结果表明,三维模型每一阶的RMSE和残差绝对值的平均值均要比二维模型的小约45%.由于采用了系数完全展开的建模方式,三维模型的系数数量约为二维模型的2倍,三维模型较低的截断阶数可以反映更多的地磁信息.本研究中的5阶三维Taylor模型基本可达到8阶Taylor模型的精度.两种模型绘制的地磁场及残差分布有较好的一致性.The inherent shortcoming of most regional models is the lack of altitude information.In order to overcome this,the objective of this study is to establish the three-dimensional（3D）model of element X,Y,Z,and Fover Chinese and its adjacent regions in 2010.0at the height of about 300 km.Based on the vector and scalar geomagnetic measuring data of CHAMP satellite,associated with 3D Taylor polynomial method,we try to create the 3D model over China and calculate the spatial distribution of geomagnetic field region.3D model not only has the advantages like simple calculation and convenient to use,but also takes into account the height.In addition,the selection of truncation level of 3D model was also discussed.In order to verifythe constructed 3D model,a comparison between 3Dand Taylor polynomial（2D）model was taken,we analyzed the Root-mean-square error（RMSE）and the residual distributions between3 Dand 2D models in different truncation level.Results showed RMSE and the mean absolute residuals of each level of the 3D model are about 45% smaller than that of 2D model.The 3D model of degree 5basically has the same precision as that of 2Dmodel of degree 8in this study.Geomagnetic distributions and residuals of3 Dand 2D models have high consistency.After comparing with 2D model,the 3D model considers the altitude information,so the precision is really improved;the coefficients show that3 D model of low degree can reflect more information and has the similar precision when compared to 2D model of high degree.

关 键 词：地磁模型 三维Taylor多项式模型 CHAMP卫星 均方偏差 

分 类 号：P318[天文地球—固体地球物理学]