The first comparison between Swarm-C accelerometer-derived thermospheric densities and physical and empirical model estimates

摘要

First systematic comparison between Swarm-C accelerometer-derivedthermospheric density against both empirical and physics-based model resultsusing multiple model performance metrics is presented. This comparison isperformed at the satellite's high temporal resolution, which provides ameaningful evaluation of the models' fidelity for orbit prediction and otherspace weather forecasting applications. The comparison against the physicalmodel is influenced by the specification of the lower atmospheric forcing, thehigh-latitude ionospheric plasma convection and solar activity. Amachine-learning exercise is also used to isolate the impact ofthermosphere-driving mechanisms. The results show that the short-timescalevariations observed by Swarm-C during periods of high solar and geomagneticactivity were better captured by the physics-based model as compared to theempirical model in this analysis. It is concluded that Swarm-C data agree wellwith the climatologies inherent within the models, and is, therefore, a usefuldataset for further model validation and scientific research.