Selçuk SAĞIR, Ramazan ATICI, İskender DÖLEK

Şiddetli Jeomanyetik Fırtınanın Gece Yarısı İyonosfer Üzerindeki Etkisinin ROTI Aracılığıyla İncelenmesi

Bu çalışmada, 6 Eylül 2017'deki X-9 ışımaları ile ilişkili koronal kütle boşalmalarının erken ulaşması ile 07-08 Eylül 2017 tarihlerinde Dünya'nın iyonosferindeki yoğun jeomanyetik fırtınanın etkisi ROTI, Toplam Elektron İçerik (TEC) indeksinin oranı (Rate of TEC Index-ROTI) aracılığıyla incelendi. Çalışma beş farklı enlem bölgesi için IGS-GPS ağına bağlı on istasyondan elde edilen TEC değerleri ile gerçekleştirilmiştir. Sonuç olarak, fırtına sırasında gece yarısı güney yarımkürenin yüksek enlem bölgesinde meydana gelen rahatsızlıkların kuzey yarımkürenin yüksek enlem bölgesinden daha büyük olduğu gözlenmiştir. Ayrıca, tedirgin günlerdeki ROTI değerlerinin (07-08 Eylül 2017) diğer günlerden daha yüksek olduğu belirlendi.

Anahtar Kelimeler:

İyonosferik TEC, ROTI, jeomanyetik fırtına

Investigation of the Severe Geomagnetic Storm Effects on Ionosphere at Nighttime through ROTI

In this study, the effect of the intense geomagnetic storm on the Earth's ionosphere during the period 07-08 September 2017 with the early arrival of coronal mass discharges associated with X-9 flares on the 6 September 2017 was investigated through ROTI, an index of Total Electron Content (TEC) ratio (ROT). The study was conducted with TEC values obtained from ten stations connected to the IGS-GPS network for five different latitude regions. As a result, it was observed that during the storm, the disturbances that occurred in the high latitude region of the southern hemisphere were more disturbed than the high latitude region of the northern hemisphere at nighttime. In addition, ROTI values were found to be higher than other days on disturbed days (07-08 September 2017).

Keywords:

Ionospheric TEC, ROTI,

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