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Equatorial enhancement of Pc5–6 magnetic storm time geomagnetic pulsations

Earth, Planets and Space volume 51, pages 959–964 (1999)Cite this article

Abstract

Geomagnetic Pc5–6 (1–4 mHz) pulsations during three magnetic storms have been analyzed using ground observations at an array of 5 Indian stations ranging from 0.8° to 25° dip latitudes and two pairs of low-latitudes (~20°)—near equator (~4–5°) stations, located at ~4 hours to the West and East from this meridian. The pulsations are found to occur as individual wave packets that are characterized by similar spectra at all stations with two dominate bands of frequencies: ~1.5–2.0 mHz and ~2.5–4.0 mHz. Very strong daytime equatorial enhancement of the wave intensity has been noted. The higher enhancement is observed near noon while it is reduced towards the morning and evening sectors. The polarization of both frequency bands at the equator is found to be almost linear, mainly along the H-direction. It has been found that the amplitude of the D-component decreased with decrease in the latitude towards the equator. One of the spectral peaks is observed exclusively at the dip equator station and it has been attributed to the generation/amplification of MHD waves by the equatorial electrojet instabilities. The mechanism of day time equatorial enhancement of long period geomagnetic pulsations and the propagation characteristics are discussed.

References

  • Bolshakova, O. V., O. K. Borovkova, Ya. F. Borovkov, N. G. Kleimenova, and J. Bitterly, Magnetic storm on 13 March 1989: The structure of extremely disturbed magnetosphere obtained from geomagnetic pulsations Pc5, Geomagn. Aeron., 34, 492–500, 1995 (English translation).

    Google Scholar 

  • Dunlop, I. S., F. W. Menk, H. J. Hansen, B. J. Fraser, and R. J. Morris, A multistation study of long period geomagnetic pulsations at cusp and boundary layers latitudes, J. Atmos. Terr. Phys., 56, 667–679, 1994.

    Article  Google Scholar 

  • Federov, E., V. Pilipenko, V. Surkov, D. R. K. Rao, and K. Yumoto, Ionospheric propagation of magnetohydrodynamic disturbances from the equatorial inosphere, J. Geophys. Res., 104, 4329–4336, 1999.

    Article  Google Scholar 

  • Green, C. A., The longitudinal phase variation of mid-latitude Pc3–4 micropulsations, Planet. Space Sci., 24, 79–85, 1976.

    Article  Google Scholar 

  • Harrold, B.G. and J. C. Samson, Standing ULF modes of the magnetosphere: a theory, Geophys. Res. Lett., 19, 1811–1814, 1992.

    Article  Google Scholar 

  • Herron, T. J., Phase characteristics of geomagnetic micropulsations, J. Geophys. Res., 71, 871–889, 1966.

    Article  Google Scholar 

  • Jain, A. R. and K. G. A. Srinivasacharya, Study of magnetic pulsations in the Indian equatorial region, J. Atmos. Terr. Phys., 37, 1477–1483, 1975.

    Article  Google Scholar 

  • Kikuchi, T., Evidence of transmission of the polar electric fields to the low latitude at time of geomagnetic sudden commencements, J. Geophys. Res., 91, 3101–3105, 1986.

    Article  Google Scholar 

  • Kikuchi, T. and T. Araki, Horizontal transmission of the polar electric field to the equator, J. Atmos. Terr. Phys., 41, 927–936, 1979.

    Article  Google Scholar 

  • Kitamura, T. I., O. Saka, M. Shimoizzumi, H. Tachihara, T. Oguti, T. Araki, N. Sato, M. Ishitsuka, O. Veliz, and J. B. Nyobe, Global mode of Pi2 waves in the equatorial regions—difference of Pi2 mode between high and equatorial latitudes, J. Geomag. Geoelectr., 40, 621–634, 1988.

    Article  Google Scholar 

  • Lilley, F. E. M. and D. J. Bennett, Micropulsations recorded by an array of magnetic variometers, J. Geophys. Res., 78, 1603–1607, 1973.

    Article  Google Scholar 

  • Liu, J. Y., Y. N. Huang, and F. T. Berkey, The phase relationship between ULF geomagnetic pulsations and HF Doppler frequency shift oscillations on March 24, 1991, J. Geomag. Geoelectr., 45, 109–114, 1993.

    Article  Google Scholar 

  • McHarg, M. G., J. V. Olson, and P. T. Newell, ULF cusp pulsations: diurnal variations and interplanetary magnetic field correlations with ground-based observations, J. Geophys. Res., 100, 19729–19742, 1995.

    Article  Google Scholar 

  • Olson, J. V. and G. Rostoker, Longitudinal phase variations of PC4–5 micropulsations, J. Geophys. Res., 83, 2481–2488, 1978.

    Article  Google Scholar 

  • Otnes, R. K. and L. Enochson, Applied Time Series Analysis, V.1 Basic Techniques, 449 pp., Wiley-Interscience, New York, 1978.

    Google Scholar 

  • Rao, D. R. K., A result on Pc3–4 waves in the Indian equatorial region, J. Geomag. Geoelectr., 48, 1443–1449, 1996.

    Article  Google Scholar 

  • Reddy, C. A., S. Ravindran, K. S. Viswanathan, B. V. Krishna Murthy, D. R. K. Rao, and T. Araki, Observations of Pc5 micropulsation-related electric field oscillations in the equatorial ionosphere, Ann. Geophys., 12, 565–573, 1994.

    Article  Google Scholar 

  • Roy, M., D. R. K. Rao, B. M. Pathan, and R. L. Asinkar, Quiet time PS6 pulsation associated with equatorial electrojet irregularities, J. Atmos. Sol.-Terr. Phys., 1999 (in press).

  • Ruohoniemi, J. M., R. A. Greenwald, K. B. Baker, and J. C. Samson, HF radar observations of Pc5 field line resonances in the midnight/early morning MLT sector, J. Geophys. Res., 96, 15697–15710, 1991.

    Article  Google Scholar 

  • Saito, T., Resonance model on Pc3 sub-tropic region, in Contribuciones Cientificas para Conmemorar el 75 Aniversario del Observatorio del Ebro, pp. 175–180, 1983.

  • Saka, O., T. I. Kitamura, M. Shimoizzumi, T. Araki, T. Oguti, O. Veliz, and M. Ishitsuka, The effects of Non-Uniform Ionosphere on the Equatorial PC Pulsations, J. Geomag. Geoelectr., 40, 635–643, 1988.

    Article  Google Scholar 

  • Samson, J. C., B. G. Harrold, J. M. Ruohoniemi, R. A. Greenwald, and A. D. M. Walker, Field line resonances associated with MHD waveguides in the magnetosphere, Geophys. Res. Lett., 19, 441–444, 1992.

    Article  Google Scholar 

  • Sarma, S. V. S. and T. S. Sastry, On the equatorial electrojet influence on geomagnetic pulsation amplitudes, J. Atmos. Terr. Phys., 57, 749–754, 1995.

    Article  Google Scholar 

  • Sarma, S. V. S., T. S. Sastry, and Y. S. Sarma, On the latitudinal variation of magneto-telluric source field in the equatorial region of India, J. Geomag. Geoelectr., 43, 677–684, 1991.

    Article  Google Scholar 

  • Sastry, T. S., Y. S. Sarma, and S. V. S. Sarma, Equatorial electrojet effects on geomagnetic pulsations, Ind. J. Radio Space Phys., 8, 249–253, 1979.

    Google Scholar 

  • Sastry, T. S., Y. S. Sarma, and S. V. S. Sarma, Daytime Pi-pulsations in the equatorial region of India, J. Atmos. Terr. Phys., 45, 733–741, 1983.

    Google Scholar 

  • Schott, J. J., N. G. Kleimenova, J. Bitterly, and O. V. Kozyreva, The strong Pc5 geomagnetic pulsations in the initial phase of the great magnetic storm of March 24, 1991, Earth Planets Space, 50, 101–106, 1998.

    Article  Google Scholar 

  • Shinohara, M., K. Yumoto, N. Hosen, A. Yoshikawa, H. Tachihara, O. Saka, T. I. Kitamura, N. B. Trivedi, J. M. Da Costa, and N. J. Schuch, Wave characteristics of geomagnetic pulsations across the dip equator, J. Geophys. Res., 103, 11745–11754, 1998.

    Article  Google Scholar 

  • Sorokin, V. and G. V. Fedorovich, Propagation of short period waves in the ionosphere, Izv. VUZov (Radiofizika), 25, 495–507, 1982.

    Google Scholar 

  • Trivedi, N. B., B. R. Arora, A. L. Padilha, J. M. Da Costa, S. L. Dutra, F. H. Chamalaun, and A. Rigoti, Global Pc5 geomagnetic pulsations of March 24, 1991, as observed along the American sector, Geophys. Res. Lett., 24, 1683–1686, 1997.

    Article  Google Scholar 

  • Walker, A. D. M., J. M. Ruohononiemi, K. B. Baker, R. A. Greenwald, and J. C. Samson, Spatial and temporal behavior of ULF pulsations observed by Goose bay HF radar, J. Geophys. Res., 97, 12187–12202, 1992.

    Article  Google Scholar 

  • Ziesolleck, C. W. S. and F. H. A. Chamalaun, A two dimensional array study of low-latitude Pc5 geomagnetic pulsations, J. Geophys. Res., 98, 13705–13713, 1993.

    Google Scholar 

  • Ziesolleck, C. W. S. and D. R. McDiarmid, Auroral latitude Pc5 field line resonances: Quantized frequencies, spatial characteristics and diurnal variation, J. Geophys. Res., 99, 5817–5830, 1994.

    Article  Google Scholar 

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Authors and Affiliations

  1. Indian Institute of Geomagnetism, Colaba, Mumbai, 400 005, India

    B. M. Pathan, D. R. K. Rao & R. L. Asinkar

  2. Institute of Physics of Earth, 123810, Russia

    N. G. Kleimenova & O. V. Kozyreva

Authors
  1. B. M. Pathan
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  2. N. G. Kleimenova
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  3. O. V. Kozyreva
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  4. D. R. K. Rao
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  5. R. L. Asinkar
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Correspondence to B. M. Pathan.

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Pathan, B.M., Kleimenova, N.G., Kozyreva, O.V. et al. Equatorial enhancement of Pc5–6 magnetic storm time geomagnetic pulsations. Earth Planet Sp 51, 959–964 (1999). https://doi.org/10.1186/BF03351566

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