Abstract
Various solar flares and coronal mass ejections were associated with the intense solar activity located at RGN 2673 based on NASA’s record. The effects of solar activity change the condition of the ionosphere leading to fading or loss of signal. The duration of signal loss may last for a few minutes or more than an hour depending on the scale of the solar flare. Having said that, such an event disturbed the HF (high-frequency) radio communication with high sunspot number (SSn) from 4th to 10th September 2017. The R1–R2 (minor moderate) and R3 (strong) radio blackouts occurred on 4th, 6th and 10th of September 2017. Therefore, this study aims to investigate and analyse the effects of intense solar activity towards HF radio communication based on the observations of Jicamarca (11.571° S, 76.525° W) and Fortaleza (3.7327° S, 38.527° W) ionosondes located at low latitudes and an amateur radio application executed at a ground station in UKM (2.92° N, 101.77° E). According to the data coverage from both the ionosondes on the specific dates, an increased value of critical frequency of F2 layer (foF2) during HF radio blackout was identified to be associated with high SSn. The X-class flares recorded on all three dates in September 2017 caused the foF2 to enhance with recovery times of tens of minutes to hours, based on the decay time of the flare. Moreover, HF selection for amateur radios experienced an increase of more than 8 MHz during the day compared to around 7 MHz on a normal day. This result is essential for frequency planning, especially for HF amateur radio users in and around Malaysia.
Similar content being viewed by others
References
N A Frissell et al Space Weather 17 118 (2019)
R Don, E Vince and W S Robert Space Weather Effects on Aviation Fall 2015 FPAW Session at NBAA Annual Convention (2015).
C Bianchi et al Adv. Space Res. 52 403 (2013)
D V Blagoveshchensky and M A Sergeeva Adv. Space Res. 63 239 (2018)
A G Elias et al J. Atmos. Sol Terr. Phys. 163 114 (2017)
D B Contreira et al Adv. Space Res. 36 2455 (2005)
L F McNamara Radio Sci. 41 1 (2006)
A D Richmond From the Sun: Auroras, Magnetic Storms, Solar Flares, Cosmic Rays, 50 35 (1998)
W H Campbell Introduction to Geomagnetic Fields, Cambridge University Press (2003)
R P Lin From the Sun: Auroras, Magnetic Storms, Solar Flares, Cosmic Rays 50 91 (1998)
K Davies Ionospheric Radio (London: IET) vol 31 (1999)
L Qian et al J. Geophys. Res. Space Phys. 124 2298 (2019)
A Johar, W R S Osman and A A Aziz Proceedings of Knowledge Management International Conference 54 (2016)
E K Nollet and H Ohto Transfus. Apheresis Sci. 49 422 (2013)
Australia Government, Bureau of Meteorology (2017).
J A Richards Radio Wave Propagation. An Introduction to Non-Specialist (Berlin: Springer) (2008)
P Wongcharoen et al (2015) Adv. Space Res. 55 2131
B Zolesi et al J. Atmos. Sol. Terr. Phys. 70 854 (2008)
F G Steward ICEPAC Technical Manual (Undated)
J M Goodman Space Weather & Telecommunications (New York: Springer) vol 782 (2006)
E Yiğit et al J. Atmos. Sol. Terr. Phys. 171 157 (2018)
Z R Xue and T K Boon Asia-Pacific Radio Science Conference 350 (2004)
ITU International Telecommunications Union, Handbook–Radiocommunication Bureau (1998)
J A Joselyn From the Sun: Auroras, Magnetic Storms, Solar Flares, Cosmic Rays 50 67 (1998)
Acknowledgements
The authors would like to extend their gratitude to the Fundamental Research Grant Scheme, code: FRGS/1/2016/TK04/UKM/02/4 for funding and supporting this research. The authors would also like to thank Space Weather Services (SWS) Bureau of Meteorology, Australia for providing the data on weather and foF2 maps and the EMBRACE Program from the National Institute for Space Research (INPE) for making the data from the Brazilian Ionosonde network available.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Abdullah, S., Talib, J. High-frequency trend during intense solar activity in September 2017: equatorial studies. Indian J Phys 95, 1967–1976 (2021). https://doi.org/10.1007/s12648-020-01893-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12648-020-01893-2