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  • Extended metric validation of a semi-physical Space Weather Modeling Framework conductance model on field-aligned current estimations
Title: Extended metric validation of a semi-physical Space Weather Modeling Framework conductance model on field-aligned current estimations
In this study, a detailed metric survey on the “Galaxy 15” (April 2010) space weather event is conducted to validate MAGNetosphere–Ionosphere–Thermosphere (MAGNIT), a semi-physical auroral ionospheric conductance model characterizing four precipitation sources, against AMPERE measurements via field-aligned current (FAC) characteristics. As part of this study, the comparative performance of three ionosphere electrodynamic specifications involving auroral conductance models, MAGNIT, Ridley Legacy Model (RLM) (empirical), and Conductance Model for Extreme Events (CMEE) (empirical), within the Space Weather Modeling Framework (SWMF), is demonstrated. Overall, MAGNIT exhibits marginally improved predictions; root mean square error values in upward and downward FACs of MAGNIT predictions compared to AMPERE data are smaller than those of CMEE and Ridley Ionosphere Model (RIM) by ∼ 12.7% and ∼ 6.24% before the storm, ∼ 4.52% and ∼ 2.13% better during the main phase, ∼ 1.98% and ∼ 1.27% worse during the second minimum, and better by ∼ 1.84% and ∼ 1.49% by the beginning of the recovery, respectively. In all three model configurations, the dusk and night magnetic local time (MLT) sectors over-predict throughout the storm, while the day and dawn MLT sectors under-predict in response to interplanetary magnetic field (IMF) conditions. In addition to accuracy and bias, similar results and conclusions are drawn from additional metrics, including in the categories of correlation, precision, extremes, and skill, and recommendations are made for the best-performing model configuration in each metric category. Visual data–model comparisons conducted by studying the FAC location and latitude/MLT spread throughout various phases of the storm suggest that the spatial extent of the FACs is captured relatively well in the night-side auroral oval, unlike in the day-side oval. The spread in latitude of the FACs matches that in the previous literature on other model performances. This information on auroral precipitation sources and their weight on FACs, along with metrics from model–data comparisons, can be used to modify MAGNIT settings to optimize SWMF model performance.  more » « less
Award ID(s):
1663885 2002574
PAR ID:
10574077
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Frontiers in Astronomy and Space Sciences
Date Published:
Journal Name:
Frontiers in Astronomy and Space Sciences
Volume:
11
ISSN:
2296-987X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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