www.ann-geophys.net/24/751/2006/ © European Geosciences Union 2006

• Main Author: S. E. Milan
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Solar wind-magnetosphere interactions; Storms and substorms; Dy; Greenland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.592.6309; http://hal.archives-ouvertes.fr/docs/00/33/00/51/PDF/angeo-24-751-2006.pdf

Abstract. We examine magnetic flux closure during an ex-tended substorm interval on 29 August 2004 involving a two-stage onset and subsequent re-intensifications. Cluster and Double Star provide observations of magnetotail dy-namics, while the corresponding auroral evolution, convec-tion response, and substorm current wedge development are monitored by IMAGE FUV, SuperDARN, and the Greenland magnetometer chain, respectively. The first stage of onset is associated with the reconnection of closed flux in the plasma sheet; this is accompanied by a short-lived auroral intensifi-cation, a modest substorm current wedge magnetic bay, but no significant ionospheric convection enhancement. The sec-ond stage follows the progression of reconnection to the open field lines of the lobes; accompanied by prolonged auroral bulge and westward-travelling surge development, enhanced