Ionospheric Response to the 21 May 2012 Annular Solar Eclipse Over Taiwan

2019 ◽  
Vol 124 (5) ◽  
pp. 3623-3636 ◽  
Author(s):  
J. Y. Liu ◽  
S. S. Yang ◽  
P. K. Rajesh ◽  
Y. Y. Sun ◽  
J. Chum ◽  
...  
2020 ◽  
Vol 125 (11) ◽  
Author(s):  
Ercha Aa ◽  
Shun‐Rong Zhang ◽  
Philip J. Erickson ◽  
Larisa P. Goncharenko ◽  
Anthea J. Coster ◽  
...  

2012 ◽  
Vol 30 (9) ◽  
pp. 1371-1377 ◽  
Author(s):  
C. K. Nayak ◽  
D. Tiwari ◽  
K. Emperumal ◽  
A. Bhattacharyya

Abstract. In this paper we present a case study of the annular solar eclipse effects on the ionization of E and F regions of equatorial ionosphere over Tirunelveli [77.8° E, 8.7° N, dip 0.4° N] by means of digital ionosonde on 15 January 2010. The maximum obscuration of the eclipse at this station was 84% and it occurred in the afternoon. The E and F1 layers of the ionosphere showed very clear decrease in their electron concentrations, whereas the F2 layer did not show appreciable changes. A reduction of 30% was observed in the foF1 during the maximum phase of the eclipse. During the beginning phase of the eclipse, an enhancement of 0.97 MHz was observed in the foF2 as compared to that of the control days. But the foF2 decreased gradually as the eclipse progressed and a decrease of 0.59 MHz was observed towards the end phase of the eclipse. Observed variations in the h'F2 and hmF2 showed lower values than the control days, although hmF2 was found to increase a bit during the eclipse. Observed variability in the E, F1 and F2 layer ionospheric parameters on the eclipse day and their departure from the control days are discussed as the combined effect of annular eclipse and presence of counter equatorial electrojet (CEEJ).


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1216
Author(s):  
Xin Wang ◽  
Bo Li ◽  
Fan Zhao ◽  
Xinyu Luo ◽  
Luxi Huang ◽  
...  

Due to the occlusion of the moon, an annular solar eclipse will have an effect on the ionosphere above the earth. The change of the ionosphere, for the low-frequency time-code signal that relies on it as a reflection medium for long-distance propagation, the signal field strength, and other parameters will also produce corresponding changes, which will affect the normal operation of the low-frequency time-code time service system. This paper selects the solar eclipse that occurred in China on 21 June 2020, and uses the existing measurement equipment to carry out experimental research on the low-frequency time-code signal. We measured and analyzed the signal field strength from 20 June 2020 to 23 June 2020, and combined solar activity data, ionospheric data, and geomagnetic data, and attempted to explore the reasons and rules of the change of signal parameters. The results showed that the field strength of the low-frequency time-code signal changed dramatically within a short time period, the max growth value can reach up to 17 dBμV/m and the variation trend yielded ‘three mutations’. This change in signal field strength is probably due to the occurrence of a solar eclipse that has an effect on the ionosphere. When the signal propagation conditions change, the signal strength will also change accordingly.


1992 ◽  
Vol 11 (2) ◽  
pp. 37-41 ◽  
Author(s):  
Jinlai Xie ◽  
Xunren Yang ◽  
Qitai Li

Can solar eclipses generate AGWs? If so, how are they excited? This is still an open question and a long-standing dispute within academic circles. The annular solar eclipse which traversed the Chinese mainland on September 23rd 1987 afforded a rare and excellent opportunity to study this problem. Vast amounts of data of microbarometric pressure at ground level, radio-sondage, solar radiation and ionospheric probing were obtained from various observation stations. By making use of these abundant data synthetically, an important conclusion has been reached: there is an obvious accord between the period of the solar eclipse, AGW and the fluctuation period of solar direct radiation. All the solar eclipse AGWs in different places come from two different kinds of atmospheric oscillation, i.e., the forced oscillation generated directly by changes in direct solar radiation and the buoyancy oscillation in the local atmosphere above various spots. The former has a longer wave period and a larger amplitude, depending directly upon the radiation change during the solar eclipse; the latter has a shorter period and smaller amplitude, depending upon thermodynamic stability in the local atmosphere during the solar eclipse and the atmospheric moisture condition.


Sign in / Sign up

Export Citation Format

Share Document