Last Updated: 06/18/2024


Version: 4.1

The Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics Model (CTIPe) model consists of four distinct components:

-A global thermosphere model; -A high-latitude ionosphere model; -A mid and low-latitude ionosphere/plasmasphere model; -An electrodynamical calculation of the global dynamo electric field.

All four components of the CTIPe are run concurrently and are fully coupled with respect to energy, momentum, and continuity.

The thermospheric code simulates the time-dependent global structure of the wind vector, temperature, and density of the neutral thermosphere by numerically solving the non-linear primitive equations of momentum, energy, and continuity on a 3D spherical polar grid rotating with the Earth. The latitude resolution is 2 deg, longitude resolution is 18 deg, and the vertical direction is divided into 15 levels in logarithm of pressure from lower boundary of 1 Pa at 80 km altitude. The equation of motion includes Coriolis effects, horizontal pressure gradients, horizontal and vertical viscosity, and ion drag. The non-linear energy equation describes horizontal and vertical advection of energy, horizontal and vertical heat conduction by both molecular and turbulent diffusion, heating by solar UV and EUV radiation, cooling by infrared radiation, and ionospheric Joule heating. The continuity equation incorporates three major species: atomic oxygen, molecular nitrogen and molecular oxygen and include chemistry, transport and the mutual diffusion between species.

The high-latitude ionosphere convection model calculates field-aligned ion velocity components from the field-aligned momentum equation. The model includes chemistry, gravity, and ion-ion and ion-neutral collisional drag. The ionosphere is computed self-consistently with the thermosphere pole-ward of 23 degrees latitude in both hemispheres. Transport under the influence of magnetospheric electric fields is explicitly treated, assuming ExB drifts and collisions with neutral particles.

The plasmasphere model solves coupled equations of continuity, momentum and energy balance along many closed flux tubes concurrently. The orientation of flux tubes is determined by eccentric dipole approximation to the Earth's magnetic field. Each flux-tube is subject to ExB drift.


CTIPe 4.1 Sample Output Diagram 1CTIPe 4.1 Sample Output Diagram 2

Change Log

Lower boundary condition: with WAM climatological fields (monthly mean zonal, meridian, and temperature)


  • Global Ionosphere
  • Thermosphere

Space Weather Impacts

  • Ionosphere variability (navigation, communications)
  • Atmosphere variability (satellite/debris drag)


  • Variablility of Plasma Density
  • Atmosphere Expansion
  • Neutral Composition Change
  • Neutral Wind Change
  • Ion Drift Velocity
  • Equatorial Anomaly
  • Traveling Ionospheric Disturbances
  • Traveling Atmospheric Disturbances


Code Languages: Fortran


Publication Policy

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