All Physics Faculty Publications

Document Type

Article

Journal/Book Title/Conference

Geophysical Research Letters

Volume

20

Issue

4

Publisher

American Geophysical Union

Publication Date

1993

First Page

313

Last Page

316

DOI

10.1029/93GL00079

Abstract

A study of the reflection of Alfvén waves at a horizontally inhomogeneous ionosphere has been carried out. In this study, the Alfvén speed above the ionosphere is assumed to be uniform and the ionosphere is treated as a height‐integrated conducting slab. Analytical and numerical results indicate that the horizontal nonuniformity of the ionospheric conductivity can lead to a rotation of the reflected wave fields and cause field‐aligned currents that originate in the ionosphere. A strong conductivity nonuniformity in the direction perpendicular to the incident wave field, large Hall to Pedersen conductivity ratios, and low conductivity values lead to a large rotation of the reflected wave field in the range from a few to 40°. The implications of the theoretical results for some ionospheric phenomena are presented, including comments on the Harang discontinuity and Sun‐aligned arcs.

Comments

Originally published by the American Geophysical Union. Note: This article appears in Geophysical Research Letters.