HR: 1340h
AN: SM23A-1171 [Abstracts]
TI: Contribution of Sudden Solar Wind Compression to Substorm Triggering
AU: * Keika, K
EM: kunihiro.keika@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042,
Austria
AU: Nakamura, R
EM: rumi.nakamura@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042,
Austria
AU: Baumjohann, W
EM: baumjohann@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042,
Austria
AU: Runov, A
EM: Andrei.Runov@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042,
Austria
AU: Zhang, T L
EM: tielong.zhang@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042,
Austria
AU: Magnes, W
EM: werner.magnes@oeaw.ac.at
AF: Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, Graz, 8042,
Austria
AU: Angelopoulos, V
EM: vassilis@ssl.berkeley.edu
AF: Space Science Laboratory, University of California Berkeley, 7 Gauss Way #7450, Berkeley,
94720-7450, United States
AU: Angelopoulos, V
EM: vassilis@ssl.berkeley.edu
AF: Institute of Geophysics and Planetary Physics, UCLA, GPP, UCLA, Box 951567, Los
Angeles, 90095, United States
AU: Sibeck, D G
EM: david.sibeck@gsfc.nasa.gov
AF: Goddard Space Flight Center, NASA, Greenbelt, MD, 20771, United States
AU: Parks, G
EM: parks@ssl.berkeley.edu
AF: Space Science Laboratory, University of California Berkeley, 7 Gauss Way #7450, Berkeley,
94720-7450, United States
AU: Singer, H
EM: Howard.Singer@noaa.gov
AF: Space Environment Center, NOAA, 325 Broadway, Boulder, 80305, United States
AU: Cully, C M
EM: cully@Colorado.EDU
AF: Laboratory for Atmospheric and Space Physics, University of Colorado at Boulder, 1234
Innovation Drive, Boulder, 80303-7814, United States
AU: Bonnell, J W
EM: jbonnell@ssl.berkeley.edu
AF: Space Science Laboratory, University of California Berkeley, 7 Gauss Way #7450, Berkeley,
94720-7450, United States
AU: Chi, P
EM: pchi@igpp.ucla.edu
AF: Institute of Geophysics and Planetary Physics, UCLA, GPP, UCLA, Box 951567, Los
Angeles, 90095, United States
AU: Glassmeier, K H
EM: kh.glassmeier@tu-bs.de
AF: Institut fuNr Geophysik und extraterrestrische Physik, TU Braunschweig, Mendelssohnstr.
3, Braunschweig, D-38106, Germany
AU: Auster, H U
EM: uli.austertu-bs.de
AF: Institut fuNr Geophysik und extraterrestrische Physik, TU Braunschweig, Mendelssohnstr.
3, Braunschweig, D-38106, Germany
AU: Fornacon, K H
EM: k-h.fornacontu-bs.de
AF: Institut fuNr Geophysik und extraterrestrische Physik, TU Braunschweig, Mendelssohnstr.
3, Braunschweig, D-38106, Germany
AU: Reeves, G
EM: reeves@lanl.gov
AF: Los Alamos National Laboratory, Los Alamos, NM, 87544, United States
AU: Yumoto, K
EM: yumoto@serc.kyushu-u.ac.jp
AF: Space Environment Research Center, Kyushu University, 6-10-1 Hakozaki Higashi-ku,
Fukuoka, 812-8581, Japan
AU: Uozumi, T
EM: uozumi@serc.kyushu-u.ac.jp
AF: Space Environment Research Center, Kyushu University, 6-10-1 Hakozaki Higashi-ku,
Fukuoka, 812-8581, Japan
AU: Klecker, B
EM: berndt.klecker@mpe.mpg.de
AF: Max Planck Institute for extraterrestrial Physics, Karl-Schwarzschild-Str. 1, Garching, 85741,
Germany
AU: Lucek, E A
EM: e.lucek@ic.ac.uk
AF: Imperial College, Prince Consort Road, London, SW7 2BZ, United Kingdom
AU: Carr, C
EM: c.m.carr@imperial.ac.uk
AF: Imperial College, Prince Consort Road, London, SW7 2BZ, United Kingdom
AU: Dandouras, I
EM: Iannis.Dandouras@cesr.fr
AF: Centre d'Etude Spatiale des Rayonnements, CNRS, 9 Avenue du Colonel Roche,
Toulouse, F-31028, France
AU: Re`me, H
EM: Henri.Reme@cesr.fr
AF: Centre d'Etude Spatiale des Rayonnements, CNRS, 9 Avenue du Colonel Roche,
Toulouse, F-31028, France
AB:
The present study investigates the contribution of a sudden solar wind compression of the magnetosphere to the
triggering of a substorm on 21 June 2007. We take into account the propagation of shock-associated
disturbances from the magnetopause to the magnetotail. Previous studies that identified interplanetary shocks
and/or discontinuities as substorm triggers have not examined this propagation in detail, which in this study can
be determined by the THEMIS observations.
A discontinuity across which the dynamic pressure increases by a factor of `2 arrived at the magnetopause near
1245 UT. The magnetic field pointed northward in both sides of the discontinuity. The Double Star Program Tan
Ce 1 detected the arrival near 1245 UT in the dayside magnetosheath on the dawn side and Cluster at 1248 UT
in the flank magnetosheath on the dawn side. Cluster observations indicate that the shock normal was inclined
duskward by about 45 deg. Compression-associated magnetic and electric field disturbances were observed by
GOES 9 at 1245:50 UT, GOES 12 at 1245:53 UT, and GOES 11 near 12:46:30 UT on the dawn side and by
THEMIS near 1246:30 UT on the dusk side, consistent with the duskward inclined shock normal. Polar/UVI
observed an auroral breakup at `1247:00 UT and `23 MLT followed by a poleward expansion. LANL
observations at `03 MLT show a slightly dispersed electron injection beginning at `1249:00 UT.
We discuss whether or not the disturbances propagating from the dayside magnetopause had the potential to
trigger the substorm. The propagation speed and direction of the compression-related disturbances are
estimated from local measurements by THEMIS as well as time lags between the GOES spacecraft. The
estimate enables us to calculate when the disturbances arrived at a substorm onset site which we determine
from aurora intensification, electron injection, and high-latitude negative bays.
DE: 2740 Magnetospheric configuration and dynamics
DE: 2784 Solar wind/magnetosphere interactions
DE: 2790 Substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting