Recent Progress in Observational Studies of Electric Fields and Currents in the Polar Ionosphere: A Review (b. Electric Fields and Current System) (Proceedings of the First Symposium on Coordinated Observations of the Ionosphere and the Magnetosphere in the Polar Regions (Part I))

Abstract

The recent development of several new observational techniques has contributed significantly to our understanding of the characteristics of electric fields and currents in the high-latitude ionosphere as well as those of auroral particle precipitation and the auroral distribution. This paper attempts to review the main results of several years of research in these diverse fields in order to construct a plausible working model that is consistent with the basic physical requirements. Various ionospheric processes including substorm variations are discussed with special emphasis on field-aligned currents. It also contains sections of recent efforts in synthesizing the vast amount of the observations of large-scale auroras, electric and magnetic fields, and currents in the ionosphere and magnetosphere, and it concludes with a list of several questions to which satisfactory agreements have not been reached.