SAPS: A new categorization for sub-auroral electric fields

Abstract

Sub‐auroral electric fields play critical roles in energizing and transporting ring current ions, as well as convecting thermal plasma in the inner magnetosphere and in the mid‐ to low‐latitude ionosphere. A number of terms have been employed to describe the sub‐auroral electric fields and many of these are specifically associated with processes established through their prior use in the literature. The continued use of descriptive terms such as penetration electric fields, polarization jets, and sub‐auroral ion drifts could lead to misunderstanding, especially when comparing the broad/narrow, persistent/transient regions of sub‐auroral electric field and plasma flow. An inclusive name for these phenomena is sub‐auroral polarization streams (SAPS).