Testing models for traveling convection vortices: Two case studies

Abstract

We use geosynchronous magnetic field observations to discriminate between two models for traveling convection vortices (TCVs) generated by pressure variations applied to the magnetosphere. According to the model of Glassmeier [1992], an azimuthal gradient in the pressure generates a single field-aligned current into the high-latitude ionosphere and a single TCV. According to the model of Southwood and Kivelson [1990], an azimuthal gradient in the pressure generates a pair of oppositely directed currents and TCVs. We reexamine two well-documented examples of TCVs and show that their signatures correspond better to the predictions of the Southwood/Kivelson model than to the predictions of the Glassmeier model.