Skip to main content

Joule heating due to vertical ion currents in the lower thermosphere over the dip equator

Abstract

The theory of equatorial electrojet predicts the presence of vertical ion currents (Pedersen currents) as a part of the electrojet current system. The vertical ion current density profile over the dip equator, that forms a part of the meridional current system is derived from an electrojet model. The joule heating due to these currents flowing upward during daytime for a local time for 1100 hrs has been estimated. The primary east-west current density of the model is kept at the same value as that measured by means of rocket-borne magnetometer on one occasion. The electrical power dissipated as heat in the narrow belt in the height region of 100–180 km is estimated and found to be significant. The height of maximum power dissipation coincides with the altitude of maximum ion velocity i.e. 122 km. By solving the heat conduction equation we obtain a maximum temperature increase of 8°K around 135 km. The importance of this localized heating in the lower thermosphere around ±2° of the dip equator is discussed.

References

  • Anandarao, B. G., Effects of gravity wave winds and wind shears on the equatorial electrojet, Geophys. Res. Lett., 3, 545–548, 1976.

    Article  Google Scholar 

  • Anandarao, B. G. and R. Raghavarao, Effects of vertical shears in the zonal winds on the electrojet, Space. Res., XIX, 283–286, 1979.

    Google Scholar 

  • Anandarao, B. G. and R. Raghavarao, Effects of vertical shears in the currents and fields of the equatorial due to zonal and meridional winds, J. Geophys. Res., 92, 2514–2526, 1987.

    Article  Google Scholar 

  • Anandarao, B. G., R. Raghavarao, J. N. Desai, and G. Haerendel, Vertical winds and turbulence over Thumba, J. Atmos. Terr. Phys., 40, 157–163, 1978.

    Article  Google Scholar 

  • Banks, P. M. and G. Kockarts, Aeronomy Part B, Academic Press, N.Y., 1973.

  • Cole, K. D., Joule heating of the upper atmosphere, Aust. J. Phys., 15, 223–235, 1962.

    Article  Google Scholar 

  • Cole, K. D., Electrodynamic heating and movement of the thermosphere, Planet. Space Sci., 19, 59–75, 1971.

    Article  Google Scholar 

  • Forbes, J. M., The equatorial electrojet, Rev. Geophys. Space Phys., 19, 469–504, 1981.

    Article  Google Scholar 

  • Gagnepain, J., M. Crochet, and A. D. Richmond, Comparison of equatorial electrojet models, J. Atmos. Terr. Phys., 39, 1119–1124, 1977.

    Article  Google Scholar 

  • Jacchia, L. G., Smithsonian. Astrophys. Obs. Special Rep., No. 375, 1977.

  • Kato, S., Joule heating at the magnetic equator, Planet. Space Sci., 11, 1297–1302, 1963.

    Article  Google Scholar 

  • Raghavarao, R. and B. G. Anandarao, Vertical winds as a plausible cause for equatorial counter-electrojet, Geophys. Res. Lett., 7, 357–360, 1980.

    Article  Google Scholar 

  • Raghavarao, R., R. Sridharan, and R. Suhasini, The importance of vertical ion currents in the nighttime ionization in the equatorial electrojet, J. Geophys. Res., 89, 11033–11037, 1984.

    Article  Google Scholar 

  • Rees, D., P. D. Bhavsar, J. N. Desai, S. P. Gupta, A. D. Farmer, and P. Rounce, Preliminary report on commonwealth collaborative rocket programme from Thumba equatorial rocket launching station for the investigation of atmospheric and ionospheric processes, Space. Res., XVI, 407–412, 1976.

    Google Scholar 

  • Sampath, S., T. S. G. Sastry, K. Oyama, and K. Hirao, Joule heating due to the equatorial electrojet as observed by rocket-borne probes, Space. Res., XIV, 253–258, 1974.

    Google Scholar 

  • Shirke, J. S., R. Sridharan, S. R. Das, A. D. Danilov, A. A. Pokhunkov, and V. A. Semenov, Simultaneous measurements of ionospheric parameters at the dip equator, Space. Res., XVII, 403–407, 1977.

    Google Scholar 

  • Untiedt, J., A model of the equatorial electrojet involving meridional currents, J. Geophys. Res., 72, 5799–5810, 1967.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Raghavarao, R., Sridharan, R. & Suhasini, R. Joule heating due to vertical ion currents in the lower thermosphere over the dip equator. Earth Planet Sp 50, 833–837 (1998). https://doi.org/10.1186/BF03352176

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1186/BF03352176

Keywords

  • Power Dissipation
  • Joule Heating
  • Vertical Wind
  • Lower Thermosphere
  • Equatorial Electrojet