Volumes and Issues  Contents of Issue 12  
Ann. Geophys., 24, 3491-3496, 2006
www.ann-geophys.net/24/3491/2006/
© European Geosciences Union 2006


Global manifestations of a substorm onset observed by a multi-satellite and ground station network

H. Wang1,*, S. Y. Ma1, H. Lühr2, Z. X. Liu3, Z. Y. Pu4, C. P. Escoubet5, H. U. Frey6, H. Réme7, and P. Ritter2
1Inst. of Ionosphere and Magnetosphere, LOGEG, CNME; College of Electronic Informatics, Wuhan University, Wuhan 430079, P. R. China
2GeoForschungsZentrum Potsdam, Telegrafenberg 14473 Potsdam, Germany
3Center for Space Science and Applied research, Chinese Academy of Sciences, Beijing, P. R. China
4School of Earth and Space Science, Peking University, Beijing 100871, P. R. China
5ESA/ESTEC (SCI-RSSD), Postbus 299, Keplerlaan 1, 2200 AG Noordwijk, The Netherlands
6Space Sciences Laboratory, University of California, Berkeley, USA
7CESR/CNRS, 31029 Toulouse, France
*now at: University of Michigan, 2455 Hayward Str., Ann Arbor, 48109, USA

Abstract. With a favorable constellation of spacecraft and ground stations, a study is made on the global manifestations of a substorm onset. The onset occurred simultaneously and conjugately in both hemispheres, confirmed by observations of the auroral breakup from IMAGE FUV-WIC and a sudden intensification of a westward electrojet from ground-based magnetometers. Concurrently with the onset, field-aligned and Hall currents in the auroral ionosphere are observed by CHAMP, which are consistent with the signature of a Harang discontinuity. Immediately after the onset a magnetic field dipolarization is clearly observed by Double Star TC-1, located near the central magnetotail and subsequently, by the Cluster quartet. The observations can be explained by a dawnward propagation of the substorm current wedge at a speed of about 300 km/s.

Full Article (PDF, 1157 KB)

Citation: Wang, H., Ma, S. Y., Lühr, H., Liu, Z. X., Pu, Z. Y., Escoubet, C. P., Frey, H. U., Réme, H., and Ritter, P.: Global manifestations of a substorm onset observed by a multi-satellite and ground station network, Ann. Geophys., 24, 3491-3496, 2006.   Bibtex   EndNote   Reference Manager