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ISSN  2096-3955

CN  10-1502/P

Citation: Zhou, R. X., Gu, X. D., Yang, K. X., Li, G. S., Ni, B. B., Yi, J., Chen, L., Zhao, F. T., Zhao, Z. Y., Wang, Q., Zhou, L. Q. (2020). A detailed investigation of low latitude tweek atmospherics observed by the WHU ELF/VLF receiver: I. Automatic detection and analysis method. Earth Planet. Phys., 4(2), 120–130.

2020, 4(2): 120-130. doi: 10.26464/epp2020018


A detailed investigation of low latitude tweek atmospherics observed by the WHU ELF/VLF receiver: I. Automatic detection and analysis method


Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China


State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China

Corresponding author: XuDong Gu, Ni,

Received Date: 2019-12-28
Web Publishing Date: 2020-03-13

As a dispersive wave mode produced by lightning strokes, tweek atmospherics provide important hints of lower ionospheric (i.e., D-region) electron density. Based on data accumulation from the WHU ELF/VLF receiver system, we develop an automatic detection module in terms of the maximum-entropy-spectral-estimation (MESE) method to identify unambiguous instances of low latitude tweeks. We justify the feasibility of our procedure through a detailed analysis of the data observed at the Suizhou Station (31.57°N, 113.32°E) on 17 February 2016. A total of 3961 tweeks were registered by visual inspection; the automatic detection method captured 4342 tweeks, of which 3361 were correct ones, producing a correctness percentage of 77.4% (= 3361/4342) and a false alarm rate of 22.6% (= 981/4342). A Short-Time Fourier Transformation (STFT) was also applied to trace the power spectral profiles of identified tweeks and to evaluate the tweek propagation distance. It is found that the fitting accuracy of the frequency–time curve and the relative difference of propagation distance between the two methods through the slope and through the intercept can be used to further improve the accuracy of automatic tweek identification. We suggest that our automatic tweek detection and analysis method therefore supplies a valuable means to investigate features of low latitude tweek atmospherics and associated ionospheric parameters comprehensively.

Key words: tweeks, automatic detection, WHU-VLF receiver

Burg, J. P. (1975). Maximum Entropy Spectrum Analysis. Stanford: Stanford University.222

Carpenter, R. J., Jordan, G. J., Macphail, M. K., and Hill, R. S. (2012). Near-tropical Early Eocene terrestrial temperatures at the Australo Antarctic margin, western Tasmania. Geology, 40(3), 267–270.

Chen, Y. P., Yang, G. B., Ni, B. B., Zhao, Z. Y., Gu, X. D., Zhou, C., and Wang, F. (2016). Development of ground-based ELF/VLF receiver system in Wuhan and its first results. Adv. Space Res., 57(9), 1871–1880.

Chen, Y. P., Ni, B. B., Gu, X. D., Zhao, Z. Y., Yang, G. B., Zhou, C., and Zhang, Y. N. (2017). First observations of low latitude whistlers using WHU ELF/VLF receiver system. Sci. China Technol. Sci., 60(1), 166–174.

Clilverd, M. A., Rodger, C. K., Thomson, N. R., Brundell, J. B., Ulich, T., Lichtenberger, J., Cobbett, N., Collier, A. B., Menk, F. W., … Turunen, E. (2009). Remote sensing space weather events: Antarctic-Arctic Radiation-belt (Dynamic) Deposition-VLF Atmospheric Research Konsortium network. Space Wea., 7(4), S04001.

Cohen, M. B., Inan, U. S., Gołkowski, M., and McCarrick, M. J. (2010). ELF/VLF wave generation via ionospheric HF heating: Experimental comparison of amplitude modulation, beam painting, and geometric modulation. J. Geophys. Res. Space Phys., 115(A2), A02302.

Dowden, R. L., Brundell, J. B., and Rodger, C. J. (2002). VLF lightning location by time of group arrival (TOGA) at multiple sites. J. Atmos. Sol.-Terr. Phys., 64(7), 817–830.

Kumar, S., Dixit, S. K., and Gwal, A. K. (1994). Propagation of tweek atmospherics in the earth-ionosphere wave guide. Il Nuovo Cimento C, 17(3), 275–280.

Kumar, S., Kishore, A., and Ramachandran, V. (2008). Higher harmonic tweek sferics observed at low latitude: estimation of VLF reflection heights and tweek propagation distance. Ann. Geophys., 26(6), 1451–1459.

Kumar, S., Deo, A., and Ramachandran, V. (2009). Nighttime D-region equivalent electron density determined from tweek sferics observed in the South Pacific Region. Earth Planets Space, 61(7), 905–911.

Lay, E. H., Holzworth, R. H., Rodger, C. J., Thomas, J. N., Pinto, O. Jr., and Dowden, R. L. (2004). WWLL global lightning detection system: Regional validation study in Brazil. Geophys. Res. Lett., 31(3), L03102.

Maurya, A. K., Singh, R., Veenadhari, B., Kumar, S., Cohen, M. B., Selvakumaran, R., Pant, P., Singh, A. K., Siingh, D., and Inan, U. S. (2012). Morphological features of tweeks and nighttime D region ionosphere at tweek reflection height from the observations in the low-latitude Indian sector. J. Geophys. Res. Space Phys., 117(A5), A05301.

Ohya, H., Shiokwa, K., and Miyoshi, Y. (2008). Development of an automatic procedure to estimate the reflection height of tweek atmospherics. Earth Planets Space, 60(8), 837–843.

Ohya, H., Shiokawa, K., and Miyoshi, Y. (2011). Long-term variations in tweek reflection height in the D and lower E regions of the ionosphere. J. Geophys. Res. Space Phys., 116(A10), A10322.

Ohya, H., Tsuchiya, F., Nakata, H., Shiokawa, K., Miyoshi, Y., Yamashita, K., and Takahashi, Y. (2012). Reflection height of daytime tweek atmospherics during the solar eclipse of 22 July 2009. J. Geophys. Res. Space Phys., 117(A11), A11310.

Ohya, H., Shiokawa, K., and Miyoshi, Y. (2015). Daytime tweek atmospherics. J. Geophys. Res. Space Phys., 120(1), 654–665.

Outsu, J. (1960). Numerical study of tweeks based on waveguide mode theory. Proc. Res. Inst. Atmos., Nagoya University, 7, 58-71.222

Ramachandran, V., Prakash, J. N., Deo, A., and Kumar, S. (2007). Lightning stroke distance estimation from single station observation and validation with WWLLN data. Ann. Geophys., 25(7), 1509–1517.

Reeve, C. D., and Rycroft, M. J. (1972). The eclipsed lower ionosphere as investigated by natural very low frequency radio signals. J. Atmos. Sol.-Terr. Phys., 34(4), 667–672.

Singh, R., Veenadhari, B., Maurya, A. K., Cohen, M. B., Kumar, S., Selvakumaran, R., Pant, P., Singh, A. K., and Inan, U. S. (2011). D-region ionosphere response to the total solar eclipse of 22 July 2009 deduced from ELF-VLF tweek observations in the Indian sector. J. Geophys. Res. Space Phys., 116(A10), A10301.

Volland, H., Schmolders, M., Prölss, G. W., and Schäfer, J. (1987). VLF propagation parameters derived from sferics observations at high southern latitudes. J. Atmos. Sol.-Terr. Phys., 49(1), 33–41.

Wang, Y. P., Lu, G. P., Ma, M., Zhang, H. B., Fan, Y. F., Liu, G. J., Wan, Z. R., Wang, Y., Peng, K. M., … Zhou, R. X. (2019). Triangulation of red sprites observed above a mesoscale convective system in North China. Earth Planet. Phys., 3(2), 111–125.

Yamashita, M. (1978). Propagation of tweek atmospherics. J. Atmos. Sol.-Terr. Phys., 40(2), 151–156.

Yi, J., Gu, X. D., Li, Z. P., Lin, R. T., Cai, Y. H., Chen, L., Ni, B. B., and Yue, X. A. (2019). Modeling and analysis of NWC signal propagation amplitude based on LWPC and IRI models. Chinese J. Geophys., 62(2), 3223–3234.

Yi, J., Gu, X. D., Cheng, W., Tang, X. Y., Chen, L., Ni, B. B., Zhou, R. X., Zhao, Z. Y., Wang, Q., and Zhou, L. Q. (2020). A detailed investigation of low latitude tweek atmospherics observed by the WHU ELF/VLF receiver: 2 Occurrence features and associated ionospheric parameters. Earth Planet. Phys., 4(3), 1–8.

Yusop, N., Ya'Acob, N., Shariff, K. K. M., Yusof, A. L., Ali, M. T., Idris, A., and Ali, D. M. (2013). Nighttime D-region ionosphere characteristics from tweek atmospherics observed in the North America Region. In 2012 IEEE Asia-Pacific Conference on Applied Electromagnetics (APACE). Melaka: IEEE.


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A detailed investigation of low latitude tweek atmospherics observed by the WHU ELF/VLF receiver: I. Automatic detection and analysis method

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