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Block diagrams of the whole TNB station: X , Y , and Z signals were processed, and then stored in a large memory.
Source publication
Measurements of the magnetic component of the Schumann resonance in the frequency range 6-14 Hz were performed
at high latitude location (TNB Antarctica; geographic coordinates: 74.7°S, 164.1°E; geomagnetic coordinates:
80.0°S, 307.7°E; LT=UT+13; MLT=UT8; altitude=28 m a.s.l.), during the two years 1996-1997. TNB
is a particularly important observ...
Contexts in source publication
Context 1
... in order to obtain measurements of the di- rectional characteristics of the noise (Palangio, 1993). A single sensor is composed of 8 coils of 50000 turns each ( fig. 1). Two of the sensors were oriented in the horizontal plane, one in the magnetic north-south ( X ) and the other in the magnetic east-west ( Y ), the third is oriented in the local vertical direction ( Z ). The magnetic declina- tion mean value at the time of measurements was 137°. The station is powered by battery and solar cells, and includes a microprocessor, filters and data collecting system. Data recording electron- ics consists of a microcomputer interface, which performs sampling, a/d conversion, and storing of X , Y and Z signal amplitudes in a small memory. At the end of each measurement the data stored in the interface memory were transferred into the microcomputer for processing. The results were stored in large memory (fig. 1). The station is therefore able to record data for long time in autonomous way. A block diagram of the whole experimental system is presented in fig. 1. The station can perform wide band geomagnetic measurements from 0.0005 Hz to 1000 Hz. To obtain the measurements considered in the present paper, signals were sampled at a frequency of 32 Hz, and then double integrated in the frequency range f = f 0 ± ∆ f /2 (where f 0 = 8 Hz and ∆ f = 6 Hz ), and in a time window of 120 s. The measurements are expressed in spectral density unit ( f T 2 /Hz). To motivate the analysis procedure we show in fig. 2 the plot of the magnetic power the horizontal components of the 8 Hz Schumann resonance mode versus the Local Time (LT), for two time intervals 5 days long, selected respectively in January and July 1996. For each day two principal peaks are evident: a first one (M1) lying in the time interval 8-12 LT, and a second one (M2) approximately at 20-21 LT. The two peak profile varies from day-to-day. We performed a data analysis to study the seasonal variation of the hour of appearance and amplitude of the two peaks. For each day we computed hourly means (LT) of the magnetic power. Then we determined peaks time positions and amplitudes using a pro- gram based on the derivative ...
Context 2
... in order to obtain measurements of the di- rectional characteristics of the noise (Palangio, 1993). A single sensor is composed of 8 coils of 50000 turns each ( fig. 1). Two of the sensors were oriented in the horizontal plane, one in the magnetic north-south ( X ) and the other in the magnetic east-west ( Y ), the third is oriented in the local vertical direction ( Z ). The magnetic declina- tion mean value at the time of measurements was 137°. The station is powered by battery and solar cells, and includes a microprocessor, filters and data collecting system. Data recording electron- ics consists of a microcomputer interface, which performs sampling, a/d conversion, and storing of X , Y and Z signal amplitudes in a small memory. At the end of each measurement the data stored in the interface memory were transferred into the microcomputer for processing. The results were stored in large memory (fig. 1). The station is therefore able to record data for long time in autonomous way. A block diagram of the whole experimental system is presented in fig. 1. The station can perform wide band geomagnetic measurements from 0.0005 Hz to 1000 Hz. To obtain the measurements considered in the present paper, signals were sampled at a frequency of 32 Hz, and then double integrated in the frequency range f = f 0 ± ∆ f /2 (where f 0 = 8 Hz and ∆ f = 6 Hz ), and in a time window of 120 s. The measurements are expressed in spectral density unit ( f T 2 /Hz). To motivate the analysis procedure we show in fig. 2 the plot of the magnetic power the horizontal components of the 8 Hz Schumann resonance mode versus the Local Time (LT), for two time intervals 5 days long, selected respectively in January and July 1996. For each day two principal peaks are evident: a first one (M1) lying in the time interval 8-12 LT, and a second one (M2) approximately at 20-21 LT. The two peak profile varies from day-to-day. We performed a data analysis to study the seasonal variation of the hour of appearance and amplitude of the two peaks. For each day we computed hourly means (LT) of the magnetic power. Then we determined peaks time positions and amplitudes using a pro- gram based on the derivative ...
Context 3
... in order to obtain measurements of the di- rectional characteristics of the noise (Palangio, 1993). A single sensor is composed of 8 coils of 50000 turns each ( fig. 1). Two of the sensors were oriented in the horizontal plane, one in the magnetic north-south ( X ) and the other in the magnetic east-west ( Y ), the third is oriented in the local vertical direction ( Z ). The magnetic declina- tion mean value at the time of measurements was 137°. The station is powered by battery and solar cells, and includes a microprocessor, filters and data collecting system. Data recording electron- ics consists of a microcomputer interface, which performs sampling, a/d conversion, and storing of X , Y and Z signal amplitudes in a small memory. At the end of each measurement the data stored in the interface memory were transferred into the microcomputer for processing. The results were stored in large memory (fig. 1). The station is therefore able to record data for long time in autonomous way. A block diagram of the whole experimental system is presented in fig. 1. The station can perform wide band geomagnetic measurements from 0.0005 Hz to 1000 Hz. To obtain the measurements considered in the present paper, signals were sampled at a frequency of 32 Hz, and then double integrated in the frequency range f = f 0 ± ∆ f /2 (where f 0 = 8 Hz and ∆ f = 6 Hz ), and in a time window of 120 s. The measurements are expressed in spectral density unit ( f T 2 /Hz). To motivate the analysis procedure we show in fig. 2 the plot of the magnetic power the horizontal components of the 8 Hz Schumann resonance mode versus the Local Time (LT), for two time intervals 5 days long, selected respectively in January and July 1996. For each day two principal peaks are evident: a first one (M1) lying in the time interval 8-12 LT, and a second one (M2) approximately at 20-21 LT. The two peak profile varies from day-to-day. We performed a data analysis to study the seasonal variation of the hour of appearance and amplitude of the two peaks. For each day we computed hourly means (LT) of the magnetic power. Then we determined peaks time positions and amplitudes using a pro- gram based on the derivative ...
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Citations
... V. Koloskov et al., 2020;O. V. Koloskov et al., 2022;Kulak et al., 2003;Nickolaenko, 1997;Nickolaenko & Hayakawa, 2014;Ondrášková et al., 2007Ondrášková et al., , 2008Ouyang, Xiao, et al., 2015;Ouyang et al., 2013;Price & Melnikov, 2004;Rodríguez-Camacho et al., 2022;Rossi et al., 2009;Sátori, 1996;Sátori & Zieger, 1996;Satori et al., 1996;Sentman, 1987;Sentman & Fraser, 1991;Shvets et al., 2010;Tatsis et al., 2020;Zhou et al., 2013a). In addition to ground-based observations, Abstract Based on 9 years of quasi-continuous data observed at extremely low-frequency electromagnetic stations, the long-term variations of Schumann resonances (SRs) are compared and analyzed. ...
Based on 9 years of quasi‐continuous data observed at extremely low‐frequency electromagnetic stations, the long‐term variations of Schumann resonances (SRs) are compared and analyzed. We obtained two major parameters, namely the peak intensity and peak frequencies by Lorentz fitting and focus on their seasonal and interannual variations of the first three modes in 10 stations. Fengning station was taken as an example to show the seasonal variations of the intensity and frequency of each electromagnetic component and each mode of SR, with the intensity reaching the maximum in Northern Hemisphere summer and minimum in winter; while the frequency has an inverse phase. And the amount they change from summer to winter also shows different characteristics. The interannual variation of the 10 stations shows the unified law of change in the magnetic field than in the electric field. Finally, in conjunction with observations from other regions of the globe, the periodic intensity variation and migration of the lighting activities were considered the dominant controlling factors for the SR parameters. And by comparing with the El Niño index and solar X‐radiation flux, the strong links between SR parameters and the 11‐year solar cycle are confirmed, and intensity enhanced under the influence the 2015/2016 super E1 Niño phenomenon.
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Schumann resonance (SR) is an electromagnetic resonance phenomenon in the Earth–ionosphere cavity exited by global lightning activities when the wavelength matches the circumference of the Earth, and the lowest four peak frequencies of SR are about 8, 14, 20, and 26 Hz. This article presents the new observational data of SR in China. The observations of two horizontal magnetic components (B
NS and B
EW) in the frequency band range of 3–29 Hz at Yongsheng observatory (26.7°N, 100.8°E) in southwestern China were mainly analyzed. It is found that the SR amplitudes at peak frequencies in B
NS and B
EW components all showed diurnal and seasonal variations, and that the SR amplitude in B
NS component is always higher than that in B
EW component. Diurnal variation of SR amplitude around equinoxes and solstices in B
NS component is related to active intervals of three global thunderstorm centers, while SR amplitude in B
EW component is the most significant at around 16 LT, corresponding to Asian center. SR amplitudes both in B
NS and B
EW components increase in the rainy season from May to September. In addition, the SR anomalies in association with the 2011 Japan earthquake are exhibited. The anomalous effect was characterized by an increase in amplitude at the lowest four SR modes beginning at 4 days before this earthquake. Upon analyzing the wave interference between the direct wave and disturbed wave scattered by localized modification of lower ionosphere over the epicenter, Asian and African thunderstorm centers are found to contribute to anomalous effect observed at Yongsheng station. Modeling results of SR regular and disturbed spectra at different local times led to the similar conclusion.
