不同尺度低纬电离层不规则体漂移特性的观测研究  

Observations on hundred meter-and meter-scale ionospheric irregularity drifts at low latitude

作　　者：郦洪柯[1,2] 宁百齐[1] 李国主[1] 

机构地区：[1]北京空间环境国家野外科学观测研究站,中国科学院地质与地球物理研究所,北京100029 [2]中国科学院研究生院,北京100049

出　　处：《地球物理学进展》2013年第2期545-553,共9页Progress in Geophysics

基　　金：国家自然科学基金(41074113,40904038,41174136);中国科学院野外观测研究台站网络创新三期项目(KZCX2-YW-Y10)共同资助

摘　　要：利用我国三亚站GPS短基线接收机阵以及VHF电离层相干散射雷达多波束扫描模式进行同时观测,对2011年10月22日至29日夜间两种不同尺度电离层不规则体的纬圈漂移速度进行比较研究.结果表明,两种不同手段观测的不同尺度不规则体漂移速度,在大小、变化趋势以及时间范围上基本一致.不规则体产生在20:00LT(LT为北京时)左右,以100～250m/s的速度东向漂移,并且速度幅值起伏较大;在不规则体发展中后期(21:00LT以后),东向漂移速度减低到50～150m/s,并延续至午夜.两种手段观测的漂移速度差异,一个重要原因可能来自于两者观测范围的不同.此外,GPS短基线接收机阵观测的400米尺度电离层不规则体通常比VHF雷达探测到的3米尺度电离层不规则体存在的时间要长.Multi-technique observations may improve our understanding on the dynamics of low latitude nighttime ionospheric irregularities. The zonal drift velocities of different-scale ionospheric irregularities, are comparatively researched using L1 band scintillation data from GPS short-baseline receivers and RTI（Range-Time-Intensity） maps from VHF coherent radar five-beam steering measurements during the period October 22-29 2011, at Sanya, China （18°N, 109°E, dip lat. 13°N）. The results indicate that the irregularities initiated mostly around 2000 LT（China Standard Time）, with highly fluctuated eastward velocities varying from 100 m/s to 250 m/s. After about 2100 LT, the zonal velocities reduced to 50-150 m/s and the irregularities continued to exist until midnight. The difference of zonal drifts measured by the two techniques could be mainly resulted from the differences in the probing area, as the GPS scintillation data was averaged from GPS satellites all over the sky while the VHF radar beam covered just a fixed area north overhead of the Sanya station. By restricting GPS scintillation data to the north sky, we could obtain a more similar result to that of the VHF radar observation. Furthernre, the 400 m scale ionospheric irregularities measured by the GPS receivers generally last longer than the 3 m scale ones observed by the VHF radar.

关 键 词：电离层不规则体 漂移速度 GPS短基线阵 VHF相干雷达 

分 类 号：P352[天文地球—空间物理学]