我国西南地区电离层垂测网数据应用研究

Vertical ionosonde net and its data application in southwestern China

本文基于我国西南地区电离层垂测网普洱站和乐山站的基础数据,结合空间天气事件指数,通过限定不同阈值的滑动平均方法,提出靠近南部的普洱站应选取中值M±1.5σ(标准差)作为限定阈值,靠近北部的乐山站应选取中值M±IQR(四分位距)作为限定阈值.在此基础上,利用本文提出的扰动识别方法,对2015年4月25日尼泊尔MS8.1地震予以分析.研究结果显示,震前1天普洱站和乐山站均出现了正向扰动,震前3小时乐山站持续出现负异常.根据规划,我们还将在西南地区建立1—2个垂测台站,架设数台被动接收垂测仪信号的电离层斜向探测仪,通过组网对西南地区上空的电离层进行监测,为分析震前电离层扰动提供数据支持.

In order to monitor the ionospheric change in southwestern China, two stations were established in Pu＇er City of Yunnan Province and Leshan Normal University of Sichuan Province jointly by Institute of Earthquake Science, China Earthquake Administration and Wuhan University. Based on thevertical ionosonde data from the two stations and space weather events, we used the moving average method with different threshold to extract ionospheric per- turbation, and selected median± 1.5Std and median＋IQR as the threshold at the stations Pu＇er and Leshan, respectively. Furthermore, using this method, we analyzed the data before Nepal Ms8. 1 earthquake occurred at 14.11 on 25 April 2015. The results showed that there were positive anomalies in April 24 at the two stations Pu＇ er and Leshan, and negative anomalies lasting for three hours at Leshan station before the Nepal earthquake. According to our plan, besides the two stations, one or two vertical ionosonde stations and several oblique ionosondes will be set up in southwestern China, which will monitor the ionosphere over the region, and provide data for analyzing seismo-ionospheric disturbance.