The Origin, Early Evolution and Predictability of Solar Eruptions

Coronal mass ejections (CMEs) were discovered in the early 1970s when spaceborne coronagraphs revealed that eruptions of plasma are ejected from the Sun. Today, it is known that the Sun produces eruptive flares, filament eruptions, coronal mass ejections and failed eruptions; all thought to be due to a release of energy stored in the coronal magnetic field during its drastic reconfiguration. This review discusses the observations and physical mechanisms behind this eruptive activity, with a view to making an assessment of the current capability of forecasting these events for space weather risk and impact mitigation. Whilst a wealth of observations exist, and detailed models have been developed, there still exists a need to draw these approaches together. In particular more realistic models are encouraged in order to asses the full range of complexity of the solar atmosphere and the criteria for The Scientific Foundation of Space Weather Edited by Rudolf von Steiger, Daniel Baker, André Balogh, Tamás Gombosi, Hannu Koskinen and Astrid Veronig B L.M. Green [email protected] T. Török [email protected] B. Vršnak [email protected] W. Manchester IV [email protected] A. Veronig [email protected] 1 Mullard Space Science Laboratory, UCL, Holmbury St. Mary, RH5 6NT, UK 2 Predictive Science Inc., 9990 Mesa Rim Rd, Ste 170, San Diego, CA 92121, USA 3 Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, 10000 Zagreb, Croatia 4 Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109, USA 5 Institute of Physics/IGAM, University of Graz, Universitaetsplatz 5, 8010 Graz, Austria 46 Page 2 of 52 L.M. Green et al. which an eruption is formed. From the observational side, a more detailed understanding of the role of photospheric flows and reconnection is needed in order to identify the evolutionary path that ultimately means a magnetic structure will erupt.