| 基于协方差矩阵的地磁场急变特征提取研究 | |
| Alternative Title | Geomagnetic jerk extraction based on the covariance matrix |
| 冯彦; 姜云杉; 顾嘉琳; 徐凡; 姜乙; 刘爽 | |
| Department | 空间科学部 |
| Source Publication | 应用地球物理
 |
| 2019 | |
| Volume | 16Issue:2Pages:153-159 |
| ISSN | 1672-7975 |
| Language | 英语 |
| Keyword | 地磁场 长期变化 协方差矩阵 地磁急变 |
| Abstract | 对43个中国地区的地磁台站数据进行归一化处理后,选取了10个质量较好的台站数据,通过计算其基于月均值的年变化以进行长期变化(SV)及地磁场急变(jerk)的研究,基于协方差矩阵分析了北向、东向及垂直特征方向的变化,发现在垂直方向受到较为明显的磁层环电流影响。为了获取干净的数据,我们计算了台站数据与全球模型-CHAOS-6预测值的残差的协方差矩阵,提取并移除了源于磁层环电流的干扰部分(对应于最大特征值/特征向量)的影响,7个欧洲地区的台站数据被选用进行比较及验证。结果显示协方差矩阵方法可较好地模拟Dst指数,并能反映较为可靠的SV情况。2014年国内北向分量dX/dt以及2003.5年东向分量dY/dt的jerk特征与欧洲台站垂直分量dZ/dt的变化高度一致,相比较CHAOS-6,协方差矩阵方法可以显示更多的SV细节。 |
| Other Abstract | We normalize data from 43 Chinese observatories and select data from ten Chinese observatories with most continuous records to assess the secular variations (SVs) and geomagnetic jerks by calculating the deviations between annual observed and CHAOS-6 model monthly means. The variations in the north, east, and vertical eigendirections are studied by using the covariance matrix of the residuals, and we find that the vertical direction is strongly affected by magnetospheric ring currents. To obtain noise-free data, we rely on the covariance matrix of the residuals to remove the noise contributions from the largest eigenvalue or vectors owing to ring currents. Finally, we compare the data from the ten Chinese observatories to seven European observatories. Clearly, the covariance matrix method can simulate the SVs of Dst, the jerk of the northward component in 2014 and that of the eastward component in 2003.5 in China are highly agree with that of Vertically downward component in Europe, compare to CHAOS-6, covariance matrix method can show more details of SVs. |
| Indexed By | CSCD |
| Citation statistics | |
| Document Type | 期刊论文 |
| Identifier | http://ir.nssc.ac.cn/handle/122/7201 |
| Collection | 空间科学部 |
| Recommended Citation GB/T 7714 | 冯彦,姜云杉,顾嘉琳,等. 基于协方差矩阵的地磁场急变特征提取研究[J]. 应用地球物理,2019,16(2):153-159. |
| APA | 冯彦,姜云杉,顾嘉琳,徐凡,姜乙,&刘爽.(2019).基于协方差矩阵的地磁场急变特征提取研究.应用地球物理,16(2),153-159. |
| MLA | 冯彦,et al."基于协方差矩阵的地磁场急变特征提取研究".应用地球物理 16.2(2019):153-159. |
| Files in This Item: | ||||||
| File Name/Size | DocType | Version | Access | License | ||
| 2019162153-159.pdf（1131KB） | 期刊论文 | 出版稿 | 开放获取 | CC BY-NC-SA | Application Full Text | |
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