地球自转对北极黄河站观测日侧极光弧运动的影响  

Motion of Dayside Auroral Arc Observed at Yellow River Station Affected by the Earth's Rotation

作　　者：丘琪[1,2] 杨惠根[2] 陆全明[1] 胡泽骏[2] QIU Qi YANG Huigen LU Quanming HU Zejun(CAS Key Laboratory of Geoseience Environment, Department of Geophysics and Planetary Science University of Science and Technology of China, Hefei 230026 SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai 200136)

机构地区：[1]中国科学技术大学地球和空间科学学院中国科学院近地空间环境重点实验室,合肥230026 [2]中国极地研究中心国家海洋局极地科学重点实验室,上海200136

出　　处：《空间科学学报》2016年第6期909-915,共7页Chinese Journal of Space Science

基　　金：国家自然科学基金重点项目(41431072);国家自然科学基金面上项目(41274164;41504115);南北极环境综合考察与评估专项(CHINARE2016-02-03;CHINARE2016-04-01);中国科学院战略性先导科技专项(XDA04060201);浦东新区科技发展基金(Pkj2013-z01);国家海洋局极地科学重点实验室开放基金(KP201303);中组部青年拔尖人才计划项目共同资助

摘　　要：利用北极黄河站全天空极光数据,采用AACGM模型,将日侧极光弧映射到地磁坐标系,定量计算地球自转导致的极光弧运动速度.对于任意一条极光弧,其偏斜角定义为极光弧方向与当地地磁东西方向的夹角.研究发现,地球自转产生的速度由极光弧离开天顶的距离和偏斜角决定,其中偏斜角的影响更为重要,其还决定速度的方向.在4年的观测数据中,提取超过40 000张出现极光弧的图像,计算极光弧偏斜角.计算结果表明,日侧极光弧的偏斜角随磁地方时增大而逐渐减小,并在大约10:00 MLT(磁地方时)附近发生反转.由于偏斜角的反转,地球自转产生的极光弧运动在晨侧多为极向运动,到午后多为赤道向运动.相比午前,午后的运动更为明显,最大速度可超过300m.s^(-1).By using of the all-sky auroral data detected at Chinese Arctic Yellow River Station,the frame of dayside auroral arc is extracted and mapped to the Magnetic Local Time（MLT）-geomagnetic Latitude（MLAT） coordinate system,and the auroral arc velocity induced by the Earth＇s rotation is calculated.For any auroral arc,its tilt is the angle between the arc direction and the local geomagnetic east-west direction.The results indicate that the velocity is determined by the distance that the arc departs away from zenith and the arc tilt.The arc tilt determines the velocity orientation,and hence is more important.In order to calculate the arc tilt,over 40000 images of dayside auroral arcs are extracted from 4 years observations of Chinese Arctic Yellow River Station.The calculation results show that arc tilt decreases as MLT increases and reverses at about 10：00 MLT.Due to the reversal of arc tilt,the arc motion induced by the Earth＇s rotation is poleward and equatorward motion at dawn and afternoon respectively.The equatorward motion of the arc is much more obvious than that of poleward motion,and its maximum velocity may exceed 300 m·s^（-1）.

关 键 词：日侧极光弧 地球自转 偏斜角 弧运动 

分 类 号：P353[天文地球—空间物理学]