www.nat-hazards-earth-syst-sci.net/10/901/2010/ doi:10.5194/nhess-10-901-2010 © Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License. Fractal analysis of subionospheric LF propagation data and consideration of the lithosphere-atmosphere-ionosphere coupling 1Department of Electronic Engineering, The University of Electro – Communications (UEC), 1-5-1 Chofugaoka, Chofu Tokyo, 182-8585, Japan 2Research Station on Seismo Electromagnetics, UEC, Tokyo, Japan 3Advanced Wireless Communications Research Station, UEC, Tokyo, Japan Abstract. Fractal analysis has been applied to the local nighttime data of subionospheric LF propagation, and the fractal dimension is estimated every day in the two distinct frequency ranges (AW: acoustic wave and AGW: atmospheric gravity wave). The data during several years are analyzed for the propagation paths from the Japanese transmitter of JJY to Moshiri (Hokkaido) and to Kochi. As the result of analysis, we come to the conclusion that when we pay attention to the period just around the earthquake, we sometimes detect some significant increases in the fractal dimension either in AW or AGW range. This indicates that the self – organization effect prior to an earthquake in the lithosphere, might be seen even in the lower ionosphere, probably in terms of atmospheric oscillation effect. Full Article (PDF, 3844 KB) Citation: Imamura, T., Ida, Y., Kasahara, Y., Nakamura, T., Hobara, Y., and Hayakawa, M.: Fractal analysis of subionospheric LF propagation data and consideration of the lithosphere-atmosphere-ionosphere coupling, Nat. Hazards Earth Syst. Sci., 10, 901-906, doi:10.5194/nhess-10-901-2010, 2010. Bibtex EndNote Reference Manager XML |
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