The Effect of Geomagnetic Storms on foF2 Values over Low Latitude Ionosonde Station

Yıl 2019, Cilt: 23 Sayı: 6, 1237 - 1241, 01.12.2019

Erdinç Timoçin

https://doi.org/10.16984/saufenbilder.559334

Cited By: 3

Öz

In this
reseach, the changes in the low latitude critical frequencies (foF2) was
investigated during the geomagnetically active hours (geomagnetic storms). The critical
frequency (foF2) data obtained for 1991 over Manila that is low latitude
ionosonde station and the planetary geomagnetic indices (K_p) were
used. The superposed epoch analysis was used as a statistical method to investigate
the change in the critical frequencies during geomagnetically active hours. The
analyzes were conducted separately for the night hours, day hours and all hours
of 1991 and they were compared with each other. The results from this research
show that the highest change (increase or decrease) in foF2 values during
geomagnetically active hours occurs at the event time (zero time) and the local
time (day or night) has a significant impact on this change of the foF2 values.
The foF2 values increase at local day hours, while the foF2 values decrease at local
night hours.

Anahtar Kelimeler

Geomagnetic storms, low latitude ionospheric critical frequency, superposed epoch analysis method

Kaynakça

• J. Lastovička, “Effects of Geomagnetic Storms in the Lower Ionosphere, Middle Atmosphere and Troposphere,” Journal of Atmospheric and Terrestrial Physics, vol. 58, no. 7, pp. 831-843, 1996.
• R. W. Schunk and A. F. Nagy, “Ionospheres-physics, plasma physics, and chemistry,” Cambridge University Press, 2000.
• A. D. Danilov, J. Lastovička, “Effects of Geomagnetic Storms on the Ionosphere and Atmosphere,” Geomagnetism and Aeronomy, vol. 2, no. 3, pp. 209-224, 2001.
• G. W. Prölss, “Physics of the Earth's Space Environment,” Berlin-Heidelberg-New York Springer-Verlag Press, 2004.
• E. Timoçin, İ. Ünal, Y. Tulunay and Ü. D. Göker, “The effect of geomagnetic activity changes on the ionospheric critical frequencies (foF2) at magnetic conjugate points,” Advances in Space Research, vol. 62, no. 4, pp. 821-828, 2018.
• E. Timoçin, İ. Ünal and Ü. D. Göker, “A comparison of IRI-2016 foF2 predictions with the observations at different latitudes during geomagnetic storms,” Geomagnetism and Aeronomy, vol. 58, no. 7, pp. 846-856, 2018.
• H. Rishbeth, “F-region storms and thermospheric circulation,” Journal of Atmospheric and Terrestrial Physics, vol.37, no. 7, pp. 1055-1064, 1975.
• G. W. Prölss, “Common origin of positive ionospheric storms at middle latitudes and the geomagnetic activity effect at low latitudes,” Journal of Geophysical Research, vol. 98, no. A4, pp. 5981-5991, 1993.
• G. W. Prölss, “Handbook of Atmospheric Electrodynamics,” CRC Press, 1995.
• G. W. Prölss, “Storm-Induced Changes in the Thermospheric Composition at Middle Latitudes,” Planetary Space Science, vol. 35, no. 6, pp. 807-811, 1987.
• M. Blanc and A. D. Richmond, “The ionospheric disturbance dynamo”, Journal of Geophysical Research, vol. 85, no. A4, pp. 1669-1686, 1980.
• B. Tsurutani, A. Mannucci, B. Iijima, M. A. Abdu, J. H. A. Sobral, W. Gonzalez, F. Guarnieri, T. Tsuda, A. Saito, K. Yumoto, B. Fejer, T. J. Fuller-Rowell, J. Kozyra, J. C. Foster, A. Costerand, V. M. Vasyliunas, “Global dayside ionospheric up lift and enhancement associated with interplanetary electric fields,” Journal of Geophysical Research, vol. 109, no. A08302, pp. 1-16, 2004.
• A. J. Mannucci, B. T. Tsurutani, B. A. Iijima, A. Komjathy, A. Saito, W. D. Gonzalez, F. L. Guarnieri, J. U. Kozyra and R. Skoug, “Dayside global ionospheric response to the major interplanetary events of October 29-30, 2003 'Halloween Storms'”, Geophysical Research Letters, vol. 32, no. 12, pp. 1-4, 2005.
• B. T. Tsurutani, O. P. Verkhoglyadova, A. J. Mannucci, A. Saito, T. Araki, K. Yumoto, T. Tsuda, M. A. Abdu, J. H. A. Sobral, W. D. Gonzalez, H. McCreadie, G. S. Lakhinaand V. M. Vasyliunas, “Prompt penetration electric fields (PPEFs) and their ionospheric effects during the great magnetic storm of 30–31 October 2003,” Journal of Geophysical Research, vol.113, no. A5, pp. 1-10, 2008.
• World Data Center (WDC), http://www.sws.bom.gov.au/World_Data_Centre.
• Y. Tulunay, “Interplanetary magnetic field and its possible effects on the mid latitude ionosphere II,” Annali Di Geofisica, vol. 34, no. 2, pp. 193-200, 1994.
• Y. Tulunay, “Variability of mid-latitude ionospheric foF2 compared to IMF polarity inversions,” Advances in Space Research, vol. 15, no. 2, pp. 35-44, 1995.