Thermospheric General Circulation and Response to Magnetospheric Forcings

  1. T. E. Moore,
  2. J. H. Waite Jr.,
  3. T. W. Moorehead and
  4. W. B. Hanson
  1. R. G. Roble

Published Online: 18 MAR 2013

DOI: 10.1029/GM044p0021

Modeling Magnetospheric Plasma

Modeling Magnetospheric Plasma

How to Cite

Roble, R. G. (1988) Thermospheric General Circulation and Response to Magnetospheric Forcings, in Modeling Magnetospheric Plasma (eds T. E. Moore, J. H. Waite, T. W. Moorehead and W. B. Hanson), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM044p0021

Author Information

  1. High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, Colorado 80307

Publication History

  1. Published Online: 18 MAR 2013
  2. Published Print: 1 JAN 1988

ISBN Information

Print ISBN: 9780875900704

Online ISBN: 9781118664414

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Keywords:

  • Space plasmas—Mathematical models;
  • Magnetosphere—Mathematical models;
  • Ionosphere—Mathematical models

Summary

The earth's thermosphere is driven primarily by the absorption of solar ultraviolet radiation at wavelengths less than 200 nm. In the upper thermosphere, solar heating drives a diurnal circulation from the dayside to the nightside of the earth. In the lower thermosphere, a semidiurnal circulation dominates. It is driven by semidiurnal in situ heating components and by upward propagating tides from the lower atmosphere. Thermospheric winds calculated by the National Center for Atmospheric Research (NCAR) thermospheric general circulation model (TGCM) have been used with a global ionospheric dynamo model to calculate the global distribution of electric currents and fields for equinox conditions during solar minimum. At high latitudes, the solar-driven circulation is modified greatly by magnetospheric convection and auroral particle precipitation. Time-dependent thermospheric responses to auroral energy and momentum sources calculated by the TGCM display a wide variety of dynamic phenomena that depends upon the nature and time history of the forcings. Results from two TGCM simulations, November 21–22, 1981, and March 22, 1979, are described.