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CME-CME Interactions as Sources of CME Helio-effectiveness

Camilla Scolini - KU Leuven; Emmanuel Chané - KU Leuven, Belgium; Manuela Temmer - University of Graz, Austria; Jens Pomoell - University of Helsinki, Finland; Emilia Kilpua - University of Helsinki, Finland; Karin Dissauer - NorthWest Research Associates, United States; Astrid Veronig - University of Graz, Austria; Erika Palmerio - Space Sciences Laboratory, University of California -- Berkeley, United States; Mateja Dumbovic - Hvar Observatory, University of Zagreb, Croatia; Jingnan Guo - University of Science and Technology of China, China; Luciano Rodriguez - Royal Observatory of Belgium, Belgium; Stefaan Poedts - KU Leuven, Belgium

Session: Interplanetary CMEs and Solar Particle Event


Coronal Mass Ejections (CMEs) are the main space weather drivers in the heliosphere. It is known that the capability of individual CMEs to drive strong disturbances at Earth (“geo-effectiveness”) and other locations (“helio-effectiveness”) primarily depends on their speed, density, and magnetic field at impact, and that CME-CME interactions can often dramatically amplify the geo-effectiveness of the individual CMEs involved. However, the actual quantification of this amplification has been rarely investigated, and previous studies have mostly focused on the near-Earth region, i.e. without considering its full space-time evolution as the CMEs propagate to 1 AU and beyond.

Here, we present a study on the role of CME-CME interactions as sources of CME helio-effectiveness by performing numerical simulations with the EUHFORIA heliospheric model. As a case study, we consider a sequence of geo-effective CMEs observed in September 2017. We perform observation-based simulations of magnetised CMEs, and quantify the resulting helio-effectiveness amplification of individual CMEs as a function of the CME-CME interaction phase and of the location within the CME structure. We then explore the possibility of existence of a “helio-effectiveness amplification zone”, i.e. a characteristic heliocentric distance where CME-CME interactions have the highest probability to develop into highly helio-effective events.

Approaching deadlines:

Registration opens:

16 July 2020

Abstract submission opens:

16 July 2020

European Space Weather Medals:

6 September 2020

Registration deadline:

25 September 2020

Registration deadline: [extended]

10 October 2020

Abstract submission deadline:

4 September 2020