Combined CUTLASS, EISCAT and ESR observations of ionospheric plasma ¯ows at the onset of an isolated substorm
Abstract. On August 21st 1998, a sharp southward turning of the IMF, following on from a 20 h period of northward directed magnetic ®eld, resulted in an isolated substorm over northern Scandinavia and Svalbard. A combination of high time resolution and large spatial scale measurements from an array...
Main Authors: | , , , , |
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Other Authors: | |
Format: | Text |
Language: | English |
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.1625 http://www.ann-geophys.net/18/1073/2000/angeo-18-1073-2000.pdf |
Summary: | Abstract. On August 21st 1998, a sharp southward turning of the IMF, following on from a 20 h period of northward directed magnetic ®eld, resulted in an isolated substorm over northern Scandinavia and Svalbard. A combination of high time resolution and large spatial scale measurements from an array of coherent scatter and incoherent scatter ionospheric radars, ground magnetometers and the Polar UVI imager has allowed the electrodynamics of the impulsive substorm electrojet region during its ®rst few minutes of evolution at the expansion phase onset to be studied in great detail. At the expansion phase onset the substorm onset region is characterised by a strong enhancement of the electron temperature and UV aurora. This poleward expanding auroral structure moves initially at 0.9 km s)1 poleward |
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