Speaker
Description
Numerical magnetofrictional simulations are valuable tools for studying the solar coronal magnetic field and making predictions useful for forecasting space weather. Such models rely upon magnetograph observations of the emergence of new magnetic flux on the Sun, but, to date, the necessary observations have only be available from Earth. Consequently, these models can incorporate new magnetic flux only within a limited range of longitudes visible from Earth. Therefore, it is instructive to assess how far this limitation impairs the accuracy of such models. In order to do so, two global coronal simulations are performed, incorporating emergent flux, in one case, simply as observed with Earth-bound magnetographs and, in the other, also including emergence on the far side of the Sun inferred from STEREO. When incorporating flux on the far side of the Sun, simulations report significantly higher total magnetic flux, energy, currents, and, which is geomagnetically influential, open magnetic flux. Structures on the eastern limb, which are rotating onto the solar disc and into view from Earth, differ widely between the two simulations, but converge considerably before reaching the western limb. How much more accurate the open v. closed magnetic field structure and non-potentiality of the magnetic field are when including flux on the far side of the Sun is demonstrated. In light of these improvements with far-side flux emergence, the importance of having full, 4π-steradian observational coverage of the Sun is underlined.
