Overview of Ionosphere-Thermosphere Modeling in CISM

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Overview of Ionosphere-Thermosphere Modeling in
CISM S.C. Solomon, A.G. Burns, G. Jee, T.L.
Killeen, J. Lei, A. Maute, L. Qian, A.D.
Richmond, R.G. Roble, W. Wang, M. Wiltberger, and
Z. Zeng High Altitude Observatory, National
Center for Atmospheric Research
Abstract The Ionosphere-Thermosphere modeling
component of the CISM project is responsible for
development of general circulation models of the
upper atmosphere system and their coupling to the
magnetosphere. The Coupled Magnetosphere-Ionosphe
re-Thermosphere model (CMIT) consists of the
Lyon-Fedder-Mobarry (LFM) Magnetosphere model
coupled to the NCAR Thermosphere-Ionosphere-Electr
odynamics General Circulation Model (TIE-GCM).
Studies using the coupled and stand-alone models
show considerable improvement over
empirical-model descriptions of the thermosphere
and ionosphere. We are working on extending
ionospheric models into the plasmasphere,
collaborating with data assimilation activities,
conducting an extensive validation effort, and
including ion outflow in the feedback to the
magnetosphere.
The Coupled Magnetosphere-Ionosphere-Thermosphere
Model (CMIT)
The NCAR Thermosphere-Ionosphere-Electrodynamics
General Circulation Model (TIE-GCM)
The December 2006 AGU Storm
Neutral density simulations over the declining
phase of solar cycle 23 made by the NCAR TIE-GCM
using observed solar spectral irradiance inputs
from measurements by the TIMED Solar EUV
Experiment. Comparison to satellite drag density
measurements shows improved agreement over
empirical models.
CMIT simulations of Total Electron Content (TEC).
GPS measurements of Total Electron Content.
Plans and Goals ITM Goals Plasmasphere
extension to TIE-GCM Solar Energetic Particle
fluxes and ionization High-resolution TIE-GCM in
coupled models Transition to TIME-GCM in coupled
models ECMWF analysis fields at lower
boundary Systematic ionospheric updates from
GAIM Near-real-time solar irradiance
inputs Short-term forecast of solar irradiance
inputs Cross-Thrust Goals Inclusion of auroral
acceleration module Specification of ion outflow
rates Plasmaspheric coupling from the Rice
Convection Model (RCM) Electric
Fields Precipitation
Vertical ion drift at the magnetic equator during
the April 2004 CAWSES event simulations by
the stand-alone TIE-GCM and CMIT compared to
radar measurements at Jicamarca.
Comparison of TIE-GCM ionospheric climatology at
low solar activity during summer 2006 to initial
measurements by the COSMIC satellites using GPS
occulations.
Center for Integrated Space Weather Modeling
Annual Site Visit 5 June 2007