中国地区地磁场时空变化特征及模型精度评估  

Spatial-temporal variation characteristics of geomagnetic field in China and model accuracy evaluation

作　　者：张秀玲[1,2] 王同利 Zhang Xiuling;Wang Tongli(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China;Beijing Baijiatuan Earth Sciences National Observation and Research Station,Beijing 100095,China;Beijing Earthquake Agency,Beijing 100081,China)

机构地区：[1]中国地震局地球物理研究所,北京100081 [2]北京白家疃地球科学国家野外科学观测研究站,北京100095 [3]北京市地震局,北京100081

出　　处：《地震学报》2025年第2期182-199,共18页Acta Seismologica Sinica

基　　金：国家重点研发计划(2023YFE0101800)资助。

摘　　要：首先,基于第十三代国际地磁参考场(IGRF-13),以五年为时间间隔,对中国地区2000—2020年地磁场七个要素(X,Y,Z,H,D,I和F)的长期变化进行了系统的分析与探讨;其次,利用中国地磁台站的实际观测数据,研究了此期间地磁场逐年变化的特点,并以五年为间隔,探讨了1960—2020年中国地区内地磁场的变化模式;最后,通过分析IGRF-13和世界地磁模型WMM2020的计算结果与实际观测值之间的差值和均方根误差,深入探究了这些模型在中国地区的适用性差异。研究结果表明:2000—2020年间,中国地磁场的总磁场强度呈现出整体逐渐增强的趋势,等值线总体呈西北—东南走向;在2000—2005年、2005—2010年以及2010—2015年这三个时段内,地磁场七个要素的等值线移动方向一致,而在2015—2020年间,等值线的移动方向与前三个阶段相反;垂直分量与总磁场强度的变化模式基本相同,但总磁场强度的变化时间相比垂直分量滞后了1—3年。中国地磁场的长期变化周期约为30年,预计未来十年地磁场将呈现下降趋势。此外,IGRF-13和WMM2020模型的计算结果与实际观测值的差值和均方根误差相当一致,表明这两个模型都能较好地反映中国地区地磁场的长期变化特征。Since 1968,the International Association of Geomagnetism and Aeronomy(IAGA)has continuously published the International Geomagnetic Reference Field(IGRF)models.In 2019,the 13th generation IGRF model(IGRF-13)was released;at the same year,the U.S.National Centers for Environmental Information(NCEI)and the British Geological Survey(BGS)jointly issued the World Magnetic Model 2020(WMM2020).This study aims to use the IGRF-13 model,along with data from Chinese geomagnetic observatories,to conduct an in-depth analysis of the spatio-temporal variation characteristics of the seven elements of the geomagnetic field:magnetic declination D,magnetic inclination I,horizontal intensity H,northward component X,eastward component Y,vertical component Z,and total intensity F from 2000 to 2020.Furthermore,this study evaluates the applicability and accuracy of the IGRF-13 and WMM2020 models in China using data from 28 Chinese geomagnetic observatories.By studying the morphological changes and trends of these elements over the aforementioned period,we aim to gain a deeper understanding of the evolution process of the geomagnetic field and provide a detailed description of geomagnetic activities in China.We selected geomagnetic observatories within China that have continuous observation records.Subsequently,the IGRF-13 model was utilized to calculate the geomagnetic field model values spanning the period from 2000 to 2020.By analyzing these model values,we studied the change characteristics of the seven elements of the geomagnetic field(D,I,H,X,Y,Z,F)in different time intervals,each interval being five years long,throughout the period from 2000 to 2020.Twelve geomagnetic observatories were chosen from different regions across eastern,southern,western,northern,and central China,all with long-term and continuous observation records and located at similar latitudes and longitudes.For the data from 2000 to 2020,we performed a first-difference analysis on the time series of H,Z,F,so as to explore the trends and short-term fluctuations of t

关 键 词：IGRF-13 WMM2020 地磁场变化 等值线 周期 

分 类 号：P318.1[天文地球—固体地球物理学]