Data of 3D MHD Simulation for manuscript "A Space Hurricane over the Earth's Polar Ionosphere"

Data of 3D MHD Simulation for manuscript "A Space Hurricane over the Earth’s Polar Ionosphere"

These data come from a fully run of a 3D MHD Simulation model that named by PPMLR-MHD model (detailed descriptions below).

There are 3 types of data files:

1) Zh14d0617_XY_Z4Re.dat, Zh14d0617_XY_Z8Re.dat and Zh14d0617_XZ_Y0Re.dat are the extracted data in XY plane at Z=4 Re and 8 Re, and XZ plane at Y=0 from the 3D simulation data at 16:18 UT;

2) RRSW_XY_8RE_Zh14d0001-1191.mat is saved time series data for the extracted parameters in XY plane at Z=8 Re.

3) 3D MFL.zip is the compressed data with a file name of pic_Zh14dxxxx_lines4_ 11.csv. These data are 3D positions of the selected magnetic field lines from the 3D simulation data. The numbered files saved the data at a certain time, for example, 0617 for 16:18 UT, 0558 for 15:48 UT, and 0678 for 16:48 UT, etc. The time resolution of the data (each file) is 30 seconds. 

The first two type files of data include the following parameters:

time, x, y, z, logrho, Vx, Vy, Vz, Bx, By, Bz, Pr, Jx, Jy, Jz, Edj

Where, time is simulation time, which need to plus the start time to transfer them to universal time: time+14:04;

             (x,y,z) are the three components of the position of simulation point in GSM coordinates;

             logrho is the plasma density at the simulation point;

             (Vx, Vy,Vz) are the three components of plasma velocity at the simulation point in GSM coordinates;

            (Bx, By,Bz) are the three components of magnetic field at the simulation point in GSM coordinates;

             Pr is the plasma dynamic presure at the simulation point;

            (Jx, Jy,Jz) are the three components of plasma electric current at the simulation point in GSM coordinates;

           Edj is the electric field E dot electric current J, E dot J.

The third type file of data including the 3D positions of the selected field lines, which can be read by the matlab code, named as  3D_Fieldlines_plot_gif.m. 

PPMLR-MHD model

The PPMLR-MHD model is on the basis of an extension of the piecewise parabolic method (1) with a Lagrangian remap to magnetohydrodynamics (MHD) (2, 3). It is a three-dimensional MHD model, designed specially for the solar wind–magnetosphere–ionosphere system (4-6). The model possesses a high resolution in capturing MHD shocks and discontinuities and a low numerical dissipation in examining possible instabilities inherent in the system (4).

The model uses a Cartesian coordinate system with the Earth’s center at the origin and X, Y, and Z axes pointing towards the Sun, the dawn-dusk direction, and the north, respectively. The size of the numerical box extends from 30 RE to –100 REalong the Sun-Earth line and from –50 RE to 50 RE in Y and Z directions, with 320×320×320 grid points and a minimum grid spacing of 0.15 RE. An inner boundary of radius 3 RE is set for the magnetosphere to avoid the complexities associated with the plasmasphere and large MHD characteristic velocity from the strong magnetic field (6). An electrostatic ionosphere shell with height-integrated conductance is imbedded, allowing an electrostatic coupling process introduced between the ionosphere and the magnetospheric inner boundary. The Earth’s magnetic field is approximated by a dipole field with a dipole moment of 8.06×1022 A/m in magnitude. The model is run to solve the whole system by inputting the real interplanetary conditions for the current event.

Reference

1. P. Colella, P. R. Woodward, The piecewise parabolic method (PPM) for gas-dynamical simulations. J. Comput. Phys.54, 174– 201 (1984).
2. Y. Q. Hu, X. C. Guo, C. Wang, On the ionospheric and reconnection potentials of the Earth: Results from global MHD simulations. J. Geophys. Res. 112, A07215 (2007).
3. B. B. Tang, C. Wang, Large scale current systems developed from substorm onset: Global MHD results. SCIENCE CHINA Technological Sciences, 61(3): 389-396(2018).
4. C. Wang et al. Magnetohydrodynamics (MHD) numerical simulations on the interaction of the solar wind with the magnetosphere: A review. Sci. China, Ser. D Earth Sci., 56(7), 1141–1157 (2013).
5. X. Guo, C. Wang, Y. Hu,Global MHD simulation of the Kelvin-Helmholtz instability at the magnetopause for northward interplanetary magnetic field. J. Geophys. Res. 115, A10218 (2010).
6. W. Li, C. Wang, B. Tang, X. Guo, D. Lin, Global features of Kelvin-Helmholtz waves at the magnetopause for northward interplanetary magnetic field. J. Geophys. Res. Space Physics. 118, 5118–5126 (2013).