Event on November 17, 1996 has been studied by using a 3-dimensional global magnetohydrodynamic (MHD) simulation of interaction between the solar wind and the earth's magnetosphere when the WIND data in the upstream was used as input of simulation. We have presented response of the earth's magnetosphere and ionosphere depending on practical variations of the solar wind and IMF (Interplanetary magnetic field) for the selected event and compare simulation results with SuperDARN observations.
In the simulation model the MHD equation and Maxwell's equation were solved as an initial and boundary problem due to modified leap-frog method. Number of grid points is (nx,ny,nz)=(500,100,200) and grid spacing is uniform and 0.5Re in three direction. Therefore the simulation domain is -220.25Re<x<30.25Re, -0.25Re<y<50.25Re, and -50.25Re<z<50.25Re.
The WIND satellite observations of the solar wind and magnetic field almost every 1 minute in GSM coordinates were used as input of this global MHD simulation. The practical input data is the solar wind number density, x-component of velocity, plasma pressure and IMF (Interplanetary magnetic field) y and z components in the GSM coordinates. In the simulation, we used the WIND data at the observed time and position as the input data at the upstream boundary at x=30Re and same time. Moreover, the electric conductivity in the ionosphere is Pedersen only and uniform by a value of 7S. Thus people need to consider these differences in compare the MHD simulation results with observations.
In summary, we could successfully carried out a global 3D MHD simulation of the solar wind-magnetosphere-ionosphere interaction when the WIND observations were used as input. Response of electric potential in the polar cap is very quick (less than 10 minutes) and strongly depends on variations of the IMF z component and the solar wind dynamic pressure. The earth's magnetosphere-ionosphere is much influenced by southward IMF than northward IMF (about 5 times). Thus effects of southward IMF become remarkable.
Response of the magnetotail and plasma sheet needs longer time (40-60 minutes) and the associated phenomena such as ionospheric convection in the midnight polar region also need longer time. We can apply the global 3D MHD model to an operational model in space weather study.
We presented three kind graphics output of cross sectional profiles of energy in the noon-midnight and equatorial planes, polar plots and configuration of magnetic field lines every 10 minutes. They are shown by movie (QuickTime and GIF formats), GIF format files and PostScript files.
We also presented three dimensional visualization of the magnetosphere by using VRML (Virtual Reality Modeling Language) and the vrml files (*.wrl) can be watched by VRML viewer such as "cosmo player" in the personal computers and workstations.
--readme.txt figure ---- hashi01.ps WIND plot given by Hashimoto hashi01.gif hashi02.ps WIND plot given by Hashimoto hashi02.gif wi991117a.ps WIND plot for 00:00-24:00 wi991117a.gif wi991117b.ps WIND plot for 17:30-20:30 wi991117b.gif potent01.ps simulated potential for 00:00-24:00 potent01.gif potent02.ps simulated potential for 17:30-20:30 potent02.gif potent03.ps simulated potential for 17:30-20:30 (scale) potent03.gif potent04.ps simulated potential for 17:30-20:30 (1 min) potent04.gif movie ---- zcc10511.gif GIF movie, polar plots (17:30-20:30 1 minute) zcc10511.mov can look by "xanim", polar plots (1 minute) zeb10511.gif GIF movie, polar plots (17:30-20:30 1 minute) zeb10511.mov can look by "xanim", polar plots (1 minute) movie2 ---- ze021390.gif GIF movie, polar plots ze021390.mov can look by "xanim", polar plots ze001067.gif GIF movie, polar plots ze001067.mov "xanim", polar plots ze073139.gif ze073139.mov zm001067.gif GIF movie, magnetic field lines zm001067.mov "xanim", magnetic field lines zm021390.gif GIF movie, magnetic field lines zm021390.mov "xanim", magnetic field lines zm073139.gif zm073139.mov zz001067.gif GIF movie, cross sectional profiles zz001067.mov "xanim", cross sectional profiles zz021390.gif zz021390.mov zz073139.gif zz073139.mov zd001067.gif GIF movie, cross sectional pattern zd001067.mov "xanim", cross sectional pattern zd021390.gif zd021390.mov zd073139.gif zd073139.mov psz25e2b ---- polar convection and potential eb1051.ps.gz PostScript file 17:31 - 17:40 | eb1221.ps.gz PostScript file 20:21 - 20:30 eb10511.gif gif file t=17:31 | eb122110.gif gif file t=20:30 psz25e2c --- vorticity and parallel velocity ec1051.ps.gz PostScript file 17:31 - 17:40 | ec1221.ps.gz PostScript file 20:21 - 20:30 ec10511.gif gif file t=17:31 | ec122110.gif gif file t=20:30 vrml -------- Three dimensional visualization of the magnetosphere by using VRML (Virtual Reality Modeling Language) vrml files (*.wrl) can be watched by cosmo player. 1835d.wrl magnetospheric structure at 18:35 1920d.wrl magnetospheric structure at 19:20 1934d.wrl 1950d.wrl 2000d.wrl 2010d.wrl 1838.B.ondo.wrl many field lines are drawn at 18:38 1842.B.ondo.wrl many field lines are drawn at 18:42 1901.B.ondo.wrl 1936.B.ondo.wrl 1939.B.ondo.wrl vrml -------- Three dimensional visualization with transparent technique 1835d2.wrl magnetospheric structure at 18:35 1920d2.wrl magnetospheric structure at 19:20 1934d2.wrl 1950d2.wrl 2000d2.wrl 2010d2.wrl 1838.C.ondo.wrl many field lines are drawn at 18:38 1842.C.ondo.wrl many field lines are drawn at 18:42 1901.C.ondo.wrl 1936.C.ondo.wrl 1939.C.ondo.wrl Correspondence of time and file name is as follows, Event on November 17, 1999 for 17:31 - 20:30 file name hh:mm ec1051.ps.gz 17:31 -17:40 PostScript file ec10511.gif 17:31 ec10512.gif 17:32 ec10513.gif 17:33 ec10514.gif 17:34 ec10515.gif 17:35 ec10516.gif 17:36 ec10517.gif 17:37 ec10518.gif 17:38 ec10519.gif 17:39 ec105110.gif 17:40 ec1061.ps.gz 17:41 -17:50 PostScript file ec10611.gif 17:41 ec1221.ps.gz 20:21 -20:30 PostScript file ec12211.gif 20:21 ec12212.gif 20:22 ec12213.gif 20:23 ec12214.gif 20:24 ec12215.gif 20:25 ec12216.gif 20:26 ec12217.gif 20:27 ec12218.gif 20:28 ec12219.gif 20:29 ec122110.gif 22:30 file name time interval zz001067.gif 00:10-12:00 every 10 minutes gif movie zz001067.mov 00:10-12:00 every 10 minutes "xanim" movie zz021390.gif 00:10-24:00 every 10 minutes gif movie zz021390.mov 00:10-24:00 every 10 minutes "xanim" movie zz073139.gif 12:10-24:00 every 10 minutes gif movie zz073139.mov 12:10-24:00 every 10 minutes "xanim" movie
Acknowledgments, The computer simulation was performed on Fujitsu VPP5000-16PE in the Computer Center of Nagoya University. The WIND data of the solar wind and magnetic field in ISTP Key Parameters was used courtesy of Drs. R.P. Lepping and K.W. Ogilvie.
CONTACTS:
Tatsuki Ogino
Solar-Terrestrial Environment Laboratory
Nagoya University
3-13 Honohara, Toyokawa, Aichi 442-8507, Japan
E-mail: ogino[AT]stelab.nagoya-u.ac.jp
TEL: +81-533-89-5207 FAX: +81-533-89-5090