Validation of Long-term Solar Coronal Modeling Using FORWARD

Abstract This research aims to evaluate the capabilities of two of the most widely used coronal models over multiple solar cycles and to study variations in solar coronal structures over an extended period across multiple channels. We have created a comprehensive database of solar corona (FORWARD data cubes) and inner heliosphere simulations using the Space Weather Modeling Framework’s Alfvén Wave Solar Atmosphere Model (AWSoM) for SC 24 and SC 25 to examine the distribution of solar wind source regions over time: coronal holes, active regions, and quiet Sun. The model accuracy was evaluated by comparing the synthetic images to Atmospheric Imaging Assembly observations from the same period across six different channels (94, 131, 171, 193, 211, and 335 Å). Additionally, to evaluate the simulations’ accuracy, we compared the AWSoM solar wind plasma parameter output at 1 au to the available OMNI data set for each Carrington rotation. Through SolarSoft’s FORWARD tool, we also accessed the Predictive Science Inc. Magnetohydrodynamic Algorithm outside a Sphere (MAS) model results, and performed the same analysis for MAS to demonstrate the evaluative power of our methodology. We share the similarities and differences in predictive power of the two models through multiple solar cycles in an unprecedented way. We found that both AWSoM and MAS slightly underperform near solar maximum—albeit in different ways with respect to active regions and coronal holes. Overall, we assert that active regions are more accurately reproduced and recognized than coronal holes in both models.