SM52A-02
Repeatable and Predictable Dynamics of the Outer Radiation Belt
Friday, 18 December 2015: 10:35
2018 (Moscone West)
Kyle R Murphy1, Ian Robert Mann2, David G Sibeck3, Louis Ozeke2, Jonathan Rae4 and Clare Watt5, (1)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (2)University of Alberta, Edmonton, AB, Canada, (3)NASA/GSFC, Greenbelt, MD, United States, (4)University College London, London, United Kingdom, (5)University of Reading, Reading, RG6, United Kingdom
Abstract:
Many believe that the response of energetic electrons in the outer radiation belt to each geomagnetic storm is unique, such that the response to any two storms in never the same. This has coined the popular phrase “If you've seen one storm, you've seen one storm”. Here we investigate the response of energetic electrons in the outer radiation belt to geomagnetic storms driven by Coronal Mass Ejections (CMEs) and Co-rotating Interaction Regions (CIRs) during the SAMPEX era through solar cycle 23 (1994-2004). We demonstrate that the outer radiation belt responds consistently and predictably to external solar wind energy input and magnetospheric wave dynamics such that larger geomagnetic storms are associated with both increased loss and acceleration. In particular, we demonstrate that the amount of electron loss in the outer radiation belt and subsequent acceleration during a geomagnetic storms is very well characterised by the total energy input from the solar wind, the minimum location of the magnetopause, minimum Dst, and ULF wave power within the inner magnetosphere. Finally we demonstrate that CMEs and CIRs have different external and internal driving conditions that produce distinct belt morphologies. However, a simple ULF wave diffusion model can reproduce both morphologies. This demonstrates how the radiation belts respond predictably for different storm drivers and magnetospheric dynamics.
