乌鲁木齐地区地磁场静日变化特征分析

ANALYSIS ON STATIC DIURNAL VARIATION CHARACTERISTICS OF GEOMAGNETIC FIELD IN URUMQI AREA

太阳静日变化Sq是地球变化磁场的重要组成部分,及时了解Sq的变化特征,有助于人们认识中低纬度地区磁场静日的周期性变化。因为Sq具有地方时依赖的特性,本文中基于乌鲁木齐台地磁场X、Y和Z分量分均值数据,结合克利时序叠加法和傅里叶谐波分析法分离基于地方时坐标的Sq,重点分析了2007~2021年乌鲁木齐地区Sq及其强度的季节变化和长期变化。结果表明:Sq(X)、Sq(Y)及Sq(Z)均存在明显的地方时变化、季节变化和太阳活动变化;各分量Sq强度随夏、春秋、冬三季均呈现出依次减弱的季节变化特征,但不同分量的逐月变化过程略有不同;从Sq的变化强度来看,最强的是Sq(Y),Sq(X)次之,Sq(Z)则表现的最弱;Sq强度与F_(107)指数呈现出显著的正相关关系,反映出了太阳活动与Sq之间的密切关联。

Solar static diurnal variation Sq is an important part of the earth's changing magnetic field.Knowing the change characteristics of Sq in time helps people understand the periodic changes of the magnetic static solar in the middle and low latitudes.Because sq has the characteristic of local time dependence,based on the fractional mean value data of X,Y and Z components of the geomagnetic field at Urumqi station,combined with Kerry time series superposition method and Fourier harmonic analysis method to separate Sq based on local time coordinates,this paper focuses on the seasonal and long-term changes of Sq and its intensity in Urumqi from 2007 to 2021.The results show that:Sq(X),Sq(Y)and Sq(Z)all have obvious local temporal changes,seasonal changes and solar activity changes;The Sq intensity of each component presents seasonal variation characteristics that gradually decrease with the three seasons of summer,spring and autumn,winter,but the month by month variation process of each component is slightly different;From the change intensity of Sq,Sq(Y)is the strongest,Sq(X)second,and Sq(Z)is the weakest;Sq intensity and F_(107) index show a obviously positive correlation relationship,reflecting the close associate between solar activity and Sq.