CEDAR Electrodynamics Thermosphere Ionosphere (ETI) Challenge for systematic assessment of ionosphere/thermosphere models: NmF2, hmF2, and vertical drift using ground‐based observations

Abstract

1] Objective quantification of model performance based on metrics helps us evaluate the current state of space physics modeling capability, address differences among various modeling approaches, and track model improvements over time. The Coupling, Energetics, and Dynamics of Atmospheric Regions (CEDAR) Electrodynamics Thermosphere Ionosphere (ETI) Challenge was initiated in 2009 to assess accuracy of various ionosphere/thermosphere models in reproducing ionosphere and thermosphere parameters. A total of nine events and five physical parameters were selected to compare between model outputs and observations. The nine events included two strong and one moderate geomagnetic storm events from GEM Challenge events and three moderate storms and three quiet periods from the first half of the International Polar Year (IPY) campaign, which lasted for 2 years, from March 2007 to March 2009. The five physical parameters selected were NmF2 and hmF2 from ISRs and LEO satellites such as CHAMP and COSMIC, vertical drifts at Jicamarca, and electron and neutral densities along the track of the CHAMP satellite. For this study, four different metrics and up to 10 models were used. In this paper, we focus on preliminary results of the study using ground-based measurements, which include NmF2 and hmF2 from Incoherent Scatter Radars (ISRs), and vertical drifts at Jicamarca. The results show that the model performance strongly depends on the type of metrics used, and thus no model is ranked top for all used metrics. The analysis further indicates that performance of the model also varies with latitude and geomagnetic activity level.Citation: Shim, J. S., et al. (2011), CEDAR Electrodynamics Thermosphere Ionosphere (ETI) Challenge for systematic assessment of ionosphere/thermosphere models: NmF2, hmF2, and vertical drift using ground-based observations, Space Weather, 9, S12003,

The International Reference Ionosphere 2012 – a model of international collaboration

“…IRI was the only data-based model, all others were physics-based models and two of these in addition employed data assimilation techniques with GPS data for the respective event periods. IRI performed very well in this challenge and was best or one of the three best in all categories considered by this challenge (Shim et al 2011(Shim et al , 2012. It is noteworthy that in several cases IRI performed better than the physics-based models with data assimilation capabilities.…”

The International Reference Ionosphere: Rawer's IRI and its status today

“…IRI performed very well in this challenge and was best or one of the three best in all categories considered by this challenge (Shim et al, 2011(Shim et al, , 2012. It is noteworthy that in several cases IRI performed better than the physics-based models with data assimilation capabilities.…”

“…In comparisons with Atmosphere Explorer C data they could show that their model provides a more accurate description of the molecular ions than the old IRI-2007 ion composition model. In the topside ionosphere the work of Bilitza et al (2007) and Truhlik et al (2009) with a large volume of satellite in situ measurements has resulted in a better understanding of the solar cycle variations of electron temperature and in the inclusion of the this effect in the IRI electron temperature model . With this latest version IRI for the first time will include a representation of auroral oval boundaries based on the work of Zhang and Paxton (2008) with observations from the Global Ultraviolet Imager (GUVI) of the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite.…”

Ionosphere‐Thermosphere Physics

“…There was also a coupling energetics and dynamics of atmospheric regions challenge for a systematic quantitative comparison of physics-based I-T models with observations; eight global models were evaluated. Nine events (two strong and four moderate storms, three quiet periods), three parameters (N m F 2 , h m F 2 , vertical drifts), and all latitudes were considered [Shim et al, 2011]. As expected, no model ranked the best when all events, parameters, and latitudes were taken together.…”