New Insights Into the Substorm Initiation Sequence From the Spatio-Temporal Development of Auroral Electrojets.

ABSTRACT: In the present study we examine three substorm events, Events 1-3, focusing on the spatio-temporal development of auroral electrojets (AEJs) before auroral breakup. In Events 1 and 2, auroral breakup was preceded by the equatorward motion of an auroral form, and the ground magnetic field changed northward and southward in the west and east of the expected equatorward flow, respectively. Provided that these magnetic disturbances were caused by local ionospheric Hall currents, this feature suggests that the equatorward flow turned both eastward and westward as it reached the equatorward part of the auroral oval. The auroral breakup took place at the eastward-turning and westward-turning branches in Events 1 and 2, respectively, and after the auroral breakup, the westward AEJ enhanced only on

SUBMITTER: Ohtani S 

PROVIDER: S-EPMC9286795 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature