We introduce a new quantitative approach for assessing the quality of coronal magnetic field models. The method compares the location of the magnetic neutral line at a specified height in the magnetic field model with the locations of localized density peaks in the coronal electron density, as measured using coronal rotational tomography. This approach is flexible to the presence of pseudostreamers in the coronal magnetic field, as well as folds in the streamer belt. We present an example application during mid-2010 when the white-light streamer-belt structure is complex and the emergence of a large active region on the far side of the Sun presents a challenge for modeling the coronal magnetic structure.

This article provides a concise review of the main physical structures and processes involved in space weather’s interconnected systems, emphasizing the critical roles played by magnetic topology and connectivity. The review covers solar drivers of space weather activity, the heliospheric environment, and the magnetospheric response, and is intended to address a growing cross-disciplinary audience interested in applied aspects of modern space weather research and forecasting. The review paper includes fundamental facts about the structure of space weather subsystems and special attention is paid to extreme space weather events associated with major solar flares, large coronal mass ejections, solar energetic particle events, and intense geomagnetic perturbations and their ionospheric footprints. This paper aims to be a first step towards understanding the magnetically connected space weather system for individuals new to the field of space weather who are interested in the basics of the space weather system and how it affects our daily lives.