Last Updated: 03/28/2024

LFM

Version: LTR-2_1_5

The CMIT model is a coupling of the LFM-MIX magnetosphere-ionosphere model with the TIE-GCM thermosphere-ionosphere model. The LFM portion of the model solves the ideal MHD equations to simulate the interaction of the solar wind with the magnetosphere. A full description of the model can be found in Lyon et al. 2004. The MIX portion of the model provides electric field inner boundary condition information to the LFM and coupled to the TIE-GCM to obtain conductance information needed for the calculation of the electric potential. Full details about the MIX model can be found in Merkin and Lyon 2010.

The TIE-GCM model is a first principle, 3D simulation of the thermosphere-ionosphere system including a self-consistent calculation of the low-latitude electric field. It solves the 3D momentum, energy, and continuity equations for the ion and neutral species. The high latitude electric field and particle precipitation parameters are provided to the TIE-GCM by the MIX module. Details of the TIE-GCM model can be found in Richmond et al. 1992. A more detailed description is also provided here.

These models are coupled together using the CISM Framework which is described in Goodrich et al. and the specific details of the CMIT model can be found in Wiltberger et al. 2004 and Wang et al. 2004.

Caveats:

The ring current included in the model has been tested to run for a few events but the results have not been verified with the modelers.

Inputs

LFM-MIX: Solar wind input including plasma density, velocities, sound speed, and magnetic field vector, Dipole tilt angle,
XML input file containing run-time parameters,
File defining magnetospheric grid

TIE-GCM: Solar EUV inputs, daily and 81-day center-averaged F10.7 solar index
GSWM specification of diurnal and semi-diurnal migrating tides

Outputs

LFM-MIX HDF4 file containing MHD state vector at magnetospheric grid points HDF4 file containing potential, current, conductance and particle energy and flux at ionospheric grid points Log file with run information TIE-GCM netCDF file containing output fields specified in latitude, longitude and pressure level including geopotential height, ion, electron, and neutral temperatures, neutral composition, ion and electron densities, and the electron potential.

RCM - Rice Convection Model of the ring current: Model influences the magnetosphere MHD solution through modifications of the plasma pressure and magnetic-field-aligned currents.

Model is time-dependent.

Change Log

Update from LTR-2_1_4

Domains

  • Geospace
  • Magnetosphere / Global Magnetosphere
  • Global Ionosphere
  • Thermosphere

Space Weather Impacts

  • Ionosphere variability (navigation, communications)
  • Near-earth radiation and plasma environment (aerospace assets functionality)

Code

Code Languages: Fortran, C, C++

Contacts

Publication Policy

Papers you must cite if you plan to publish the results: Lyon et al. (2004) and Merkin&Lyon (2010)

In addition to any model-specific policy, please refer to the General Publication Policy.