MHD Simulation of the Shock Wave Event on October 24, 2003
- Paper number
IAC-05-D5.1.01
- Author
Dr. Tatsuki Ogino, Nagoya University, Japan
- Year
2005
- Abstract
There happened two very large magnetic storms at the end of October (10/29-31), 2003. The DST to show the magnitude of storms was -(350-400) nT and the AE (Auroral Electrojet) was beyond 4000 nT. Before the large magnetic storm event, remarkable magnetic storms were not happened in October. However, abnormal operation occurred in the Japanese satellite for environment observation technology, ADEOS-II (Midori-II) on October 24. The electric power generated by the solar cell was lowering for 16:13-16:17 UT on 10/24 (01:13-01:17 JST on 10/25). On the particular day, the SC was observed at 15:25 UT in the Kakioka geomagnetic data, which suggest arrival of a shock wave at magnetopause. Really, an interplanetary shock wave was observed at 14:50 UT by the ACE satellite which was located at (x,y,z)-(231,40,-21) Re. Velocity of the shock wave increased from 430 km/s to 600 km/s. The maximum of AE reached about 2000 nT at 15:40 UT and magnetic storm did not occur on that day (DST > -65 nT). We have simulated the shock wave event on October 24, 2003 by using a 3-dimensional global magnetohydrodynamic (MHD) model to solve interaction between the solar wind and earth's magnetosphere when the ACE satellite data every 1 minute used as input of simulation. The used ACE data are the density, velocity and plasma pressure of solar wind and IMF (Interplanetary Magnetic Field) By and Bz components. Then the IMF Bx component is not included. The simulation interval is 10:00-17:00 UT and the simulation data at 14:00 UT on October, 1999 was used as an initial condition at 10:00 UT. Simulation results are not seriously affected by initial condition 2 hours later, so the simulation results will be discussed for 12:00-17:00 UT. Characteristic features of the ACE data are the arrival of shock wave at 14:50, and variations of IMF By at 15:30, 17:10 and 18:30 UT at the ACE position. It takes about 39 minutes when disturbances propagate from the ACE position to the magnetopause. Therefore the shock wave arrives at the magnetopause at 15:29 UT and the first variation of IMF By does at 16:09 UT before lowering the electric power ADEOS-II satellite. Before arrival of the shock wave, the earth's magnetosphere has a tail-like configuration with inclined thin plasma sheet due to southward and dawnward IMF. The magnetosphere shrinks at the time of shock arrival and the magnetopause approaches the geosynchronous orbit. Then plasma sheet plasma goes around the dayside magnetosphere from the magnetotail along dawn/dusk magnetosphere by magnetospheric convection. Inclination of the plasma sheet is reversed in y-z cross section as the IMF By changes from negative to positive at 16:09 UT. In the case, the plasma sheet is twisted, a plasma extension (or lobe bifurcation) appears and the plasma sheet extension surprisingly seems to connect with the earth's ionosphere.
- Abstract document
- Manuscript document
IAC-05-D5.1.01.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.