Last Updated: 04/15/2024


Version: 20230131

The Comprehensive Inner-Magnetosphere Ionosphere (CIMI) model is a bounce-averaged kinetic model of the ring current and radiation belts. This model calculates the temporal and spatial variation of the phase space density of ring current and radiation belt species: H+ and O+ in the energy range of 0.1 - 400 keV and electrons (e-) in the energy range of 1 - 4000 keV. The model considers particle drift in realistic, time-varying magnetic field, and self-consistent electric field that is solved taking into account current closure in the ionosphere. CIMI also considers charge exchange loss, energy and pitch-angle diffusion due to whistler mode chorus waves and plasmaspheric hiss. The simulation region is from the dayside magnetopause to the nightside boundary at 10-15 earth radii. The model is an initial-boundary-value problem, so initial distribution and boundary distribution as a function of time are required to run the model.

CIMI can be coupled with global MHD models. This type of code merging has been done with CIMI's predecessors: the CRCM (Comprehensive Ring Current Model) and RBE (Radiation Belt Environment) model [e.g., Glocer et al., 2011, 2013].

CIMI is thus a powerful tool for studying the dynamics of the ring current, radiation belts, and plasmasphere along with how they respond to solar wind input and their couplings with the ionosphere. Besides its various science applications, it also has great space weather potential.


Strengths: Combine the strengths of the Comprehensive Ring Current Model (CRCM) and the Radiation Belt Environment (RBE) model. Limitations: This version of CIMI uses empirical magnetic field models of T96 or T04. It does not consider the magnetic perturbation from the ring current and the transport due to MHD waves.


3D Magnetic Fields (Selection of Tsyganenko field models)

Ionospheric Electric Potentials at CIMI poleward boundary at 70.3° magnetic latitude (e.g., Weimer 2005)

Ionospheric quiet-time conductances (F10.7 solar irradiation index) and auroral conductances (Kp driven)

Solar wind speed, density and magnetic field, Dst, AE, AL index values to obtain plasma boundary conditions and drive the wave power model and magnetic field model


Equatorial H+, O+ and e- fluxes as functions of time, energy and pitch angle. Fluxes at off-equator can be obtained by mapping flux along a field line according to the equatorial pitch-angle distribution.

Plasmasphere density

Ionospheric potentials, Region 2 field aligned current and electron precipitation.

Model is time-dependent.

Change Log

The main differences between this version and the last one are:

  • All the wave diffusion coefficients were provided by Qianli Ma from BU
  • IGRF internal field is ready to be used. Just set intB=1 in cimi.dat. Set intB=0 if dipole internal is desired.


  • Geospace
  • Magnetosphere / Inner Magnetosphere / RingCurrent
  • Magnetosphere / Inner Magnetosphere / RadiationBelt

Space Weather Impacts

  • Near-earth radiation and plasma environment (aerospace assets functionality)


  • Ultra Low Frequency Waves
  • Whistler Chorus Waves
  • Plasmaspheric Hiss
  • Electromagnetic Ion Cyclotron Waves
  • Other Tyes of Waves
  • Wave-particle Interactions
  • Particle Dynamics
  • Plasmasphere / Plasmapause Dynamics
  • Inner Magnetosphere-ionosphere-thermosphere Coupling
  • Inner Magnetosphere and Outer Magnetosphere / Tail Coupling
  • Seed Population for the Ring Current and Radiation Belt / Preconditioning



Publication Policy

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