Visualizing CMEs and Predicting Geomagnetic Storms from Solar Magnetic Fields

Abstract

Because solar photospheric magnetic fields are the main source of the magnetic field in the corona and interplanetary space, changes in the photospheric field may be expected to drive transients in both regions. However, because the solar field is both complex and influenced by the solar wind, it is difficult to determine whether specific photospheric field features underlie the important transients called Coronal Mass Ejections (CMEs). Models enable us to link the photospheric field to coronal field changes and visualize the response. The potential field source surface (PFSS) model is known for its combination of relative simplicity and ability to approximate coronal hole geometry and eclipse images. We utilize PFSS models and specialized synoptic maps of the solar magnetic field to study the relationship between coronal field changes and CMEs, and to attempt to visualize CMEs and predict geomagnetic storms. For prediction purposes, updated synoptic maps in real time are needed. Several solar observatories and SOHO/MDI are currently providing such maps on a roughly daily basis, although the potential exists for hourly updates. Our results to date suggest that the combination of photospheric field observations and coronal models can provide a useful addition to the collection of space weather forecast tools.