Simulation Grid Choices for GUMICS Model

GUMICS uses an adaptive grid in GSE coordinates with the dipole tilt set to a fixed position (time-varying dipole orientation not available). The grid is primarily defined by the adaptation level which specified how many times a cell can be subdivided (in half in each spatial direction) from the coarsest resolution of 8 RE in the grid.

Simulation box size:
-223 RE < X < 33 RE
-64 RE < Y,Z < 64 RE

These grids are offered at CCMC:

  • Adaption level 4:
    Plot of adapt=4 GUMICS grid in near-Earth magnetosphere
    This grid has the finest resoluton of 0.5 RE. We set the maximum number of grid cells to 500,000 but on average the grid has about 100,000 cells.
  • Adaption level 5:
    Plot of adapt=5 GUMICS grid in near-Earth magnetosphere
    This grid has the finest resoluton of 0.25 RE. We set a maximum number of cells to 1,000,000 but the grid usually has between 350,000 and 400,000 cells.
  • Adaption level 6:
    Plot of adapt=6 GUMICS grid in near-Earth magnetosphere Y=0, closeup around Earth
    This grid has the finest resoluton of 0.125 RE. We set a maximum number of cells to 3,000,000 but the grid usually has between 1,350,000 and 1,380,000 cells.
The finest resolution is assigned adaptively depending on the gradients found and will be found:
  • Near Earth:
    The cells are finest at and near the Earth boundary at R=3.7 RE. Maximum adaptation is prescribed to ensure best resolution.
  • Magnetopause and bow shock
    The model detects boundaries and attempts to resolve them.
  • Plasmasheet
    In regions where physical quantities vary strongly the grid resolution will be improved within the maximum adaptation level and allowed number of grid cells.

You can examine the grids in more detail by viewing the results of a particular run and choosing the "Show simulation grid" option.

Last update: Feb. 4, 2020 by Lutz Rastätter