Testing models for traveling convection vortices: Two case studies

We use geosynchronous magnetic field observations to discriminate between t wo models for traveling convection vortices (TCVs) generated by pressure va riations applied to the magnetosphere. According to the model of Glassmeier [1992], an azimuthal gradient in the pressure generates a single field-ali gned 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 ree xamine two well-documented examples of TCVs and show that their signatures correspond better to the predictions of the Southwood/Kivelson model than t o the predictions of the Glassmeier model.