Abstract—

Variations in solar, geomagnetic, and seismic activity cause disturbance in the ionosphere that can be monitored effectively using GPS observations. Total electron content (TEC) is an effective parameter to understand structure of ionosphere and investigate ionospheric variability by making use of GPS receivers. The aim of this study is to determine TEC variations caused by three magnetic storms (Kp ≥ 8) occurred between 2012‒2017 years over ISTA station. GNSS-TEC was computed for 20 days before and day of magnetic storm. After that, 27 quiet days were defined to detect ionospheric disturbance during storm. Using statistical method, averages of TEC values were computed to obtain upper and lower bounds. Firstly, (Kp = 8) magnetic storm occured on 09.03.2012 was investigated and positive disturbance (about 11 TECU) was determined. Secondly, (Kp = 8.3) magnetic storm occured on 22.06.2015 was analyzed and negative disturbance (about 6 TECU) was obtained during magnetic storm. Thirdly, (Kp = 8.3) magnetic storm occured on 08.09.017 was discussed and positive disturbance (about 4 TECU) was confirmed.

中文翻译：

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土耳其上空电磁风暴期间电离层变化的调查

摘要—

太阳，地磁和地震活动的变化会引起电离层的干扰，可以使用GPS观测有效地对其进行监视。总电子含量（TEC）是了解电离层结构并利用GPS接收器研究电离层变化性的有效参数。这项研究的目的是确定由ISTA台站2012年至2017年之间发生的三场电磁风暴（Kp≥8）引起的TEC变化。GNSS-TEC是在磁暴发生之前和当天进行了20天的计算。此后，定义了27个安静的日子来检测风暴期间的电离层干扰。使用统计方法，计算TEC值的平均值以获得上限和下限。首先，（Kp= 8）调查了2012年3月9日发生的磁暴，并确定了正干扰（大约11 TECU）。其次，分析了（Kp = 8.3）2015年6月22日发生的磁暴，并在磁暴期间获得了负面干扰（约6 TECU）。第三，讨论了在08.09.017发生的（Kp = 8.3）磁暴，并确认了正干扰（大约4 TECU）。