Ionospheric Response to an Auroral Substorm

Authors

Robert W. Schunk, Utah State UniversityFollow
L. Zhu
Jan Josef Sojka, Utah State UniversityFollow
M. D. Bowline, Utah State University

Document Type

Article

Journal/Book Title/Conference

Geophysical Research Letters

Volume

24

Issue

16

Publication Date

1997

First Page

1979

Last Page

1982

Abstract

The response of the ionosphere to a representative auroral substorm was simulated. The response was found to be significant at all altitudes in a large spatial region near midnight magnetic local time. In this midnight region, there were T_e and T_i hot spots, substantial O⁺ → NO⁺ composition changes, non‐Maxwellian velocity distributions, transient ion upwellings, a large‐scale lowering of the F‐layer, ionization peaks that occur in the E‐region, and sharp horizontal gradients. Also, during the expansion phase, the E‐region densities increase due to auroral precipitation, while the plasma densities above 300 km decrease due to the overall lowering of the ionosphere. The net result is that the temporal morphologies of the plasma densities at high and low altitudes are opposite during this part of the substorm. These complex features indicate that care must be exercised when interpreting plasma measurements from both ground‐based and space‐based instruments.

Comments

Published by American Geophysical Union in Geophysical Research Letters.

Recommended Citation

Schunk, R. W., L. Zhu, J. J. Sojka, and M. D. Bowline (1997), Ionospheric response to an auroral substorm, Geophys. Res. Lett., 24(16), 1979–1982, doi:10.1029/97GL01252.