Validation of Ionospheric Specifications During Geomagnetic Storms: TEC
and foF2 during the 2013 March Storm Event-II
Abstract
Assessing space weather modeling capability is a key element in
improving existing models and developing new ones. In order to track
improvement of the models and investigate impacts of forcing, from the
lower atmosphere below and from the magnetosphere above, on the
performance of ionosphere-thermosphere models, we expand our previous
assessment for 2013 March storm event [Shim et al., 2018]. In this
study, we evaluate new simulations from upgraded models (Coupled
Thermosphere Ionosphere Plasmasphere Electrodynamics (CTIPe) model
version 4.1 and Global Ionosphere Thermosphere Model (GITM) version
21.11) and from NCAR Whole Atmosphere Community Climate Model with
thermosphere and ionosphere extension (WACCM-X) version 2.2 including 8
simulations in the previous study. A simulation of NCAR
Thermosphere-Ionosphere-Electrodynamics General Circulation Model
version 2 (TIE-GCM 2) is also included for comparison with WACCM-X. TEC
and foF2 changes from quiet-time background are considered to evaluate
the model performance on the storm impacts. For evaluation, we employ 4
skill scores: Correlation coefficient (CC), root-mean square error
(RMSE), ratio of the modeled to observed maximum percentage changes
(Yield), and timing error(TE). It is found that the models tend to
underestimate the storm-time enhancements of foF2 (F2-layer critical
frequency) and TEC (Total Electron Content) and to predict foF2 and/or
TEC better in the North America but worse in the Southern Hemisphere.
The ensemble simulation for TEC is comparable to results from a data
assimilation model (Utah State University-Global Assimilation of
Ionospheric Measurement (USU-GAIM)) with differences in skill score less
than 3% and 6% for CC and RMSE, respectively.