In situ spatiotemporal measurements of the detailed azimuthal substructure of the substorm current wedge.

ABSTRACT: The substorm current wedge (SCW) is a fundamental component of geomagnetic substorms. Models tend to describe the SCW as a simple line current flowing into the ionosphere toward dawn and out of the ionosphere toward dusk, linked by a westward electrojet. We use multispacecraft observations from perigee passes of the Cluster 1 and 4 spacecraft during a substorm on 15 January 2010, in conjunction with ground-based observations, to examine the spatial structuring and temporal variability of the SCW. At this time, the spacecraft traveled east-west azimuthally above the auroral region. We show that the SCW has significant azimuthal substructure on scales of 100 km at altitudes of 4000-7000 km. We identify 26 individual current sheets in the Cluster 4 data and 34 individual current sheets in the

SUBMITTER: Forsyth C 

PROVIDER: S-EPMC4497475 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature