Substorm Current Wedge Revisited

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Journal Title
Journal ISSN
Volume Title
School of Electrical Engineering | B1 Kirjoitus tieteellisessä aikakauslehdessä
Date
2014
Department
Major/Subject
Mcode
Degree programme
Language
en
Pages
46 p.
Series
Space Science Reviews. 4 December 2014
Abstract
Almost 40 years ago the concept of the substorm current wedge was developed to explain the magnetic signatures observed on the ground and in geosynchronous orbit during substorm expansion. In the ensuing decades new observations, including radar and low-altitude spacecraft, MHD simulations, and theoretical considerations have tremendously advanced our understanding of this system. The AMPTE/IRM, THEMIS and Cluster missions have added considerable observational knowledge, especially on the important role of fast flows in producing the stresses that generate the substorm current wedge. Recent detailed, multi-spacecraft, multi-instrument observations both in the magnetosphere and in the ionosphere have brought a wealth of new information about the details of the temporal evolution and structure of the current system. While the large-scale picture remains valid, the new details call for revision and an update of the original view. In this paper we briefly review the historical development of the substorm current wedge, review recent in situ and ground-based observations and theoretical work, and discuss the current active research areas. We conclude with a revised, time-dependent picture of the substorm current wedge that follows its evolution from the initial substorm flows through substorm expansion and recovery.
Description
Keywords
substorm, substorm current wedge, field-aligned currents, Birkeland currents
Other note
Citation
Kepko, Larry. & McPherron, R. L. & Amm, O. & Apatenkov, S. & Baumjohann, W. & Birn, J. & Lester, M. & Nakamura, R. & Pulkkinen, T. I. & Sergeev, V. 2014. Substorm Current Wedge Revisited. Space Science Reviews, nro 4, December 2014. P. 46 p. 1572-9672 (electronic). DOI: 10.1007/s11214-014-0124-9