Journal of Geophysical Research: Space Physics
© 2014 American Geophysical Union
Impact Factor: 3.174
ISI Journal Citation Reports © Ranking: 2012: 23/170 (Geosciences Multidisciplinary)
Online ISSN: 2169-9402
Associated Title(s): Journal of Geophysical Research
Coupled model boosts reproduction of inner magnetosphere ring current
The ring current that circles the Earth a few Earth radii above the surface consists of energetic ions and electrons and plays an important role in the space environment. During geomagnetic storms, the flow in the ring current rises dramatically. The behavior of the ring current and other features of the inner magnetosphere depend strongly on conditions in other regions of the magnetosphere. The small scale of the particle dynamics that drive the ring current, as compared to the vast spatial scale of the entire magnetosphere, makes it difficult to represent both the nuance of the inner magnetosphere and the full scope of the magnetospheric system.
By tying two models together, Glocer et al. developed a coupled model that can represent both the complex inner magnetosphere while also accounting for broader magnetospheric behavior. The authors used the Comprehensive Ring Current Model (CRCM) for the inner magnetosphere and the Block-Adaptive-Tree Solar-wind Roe-type Upwind Scheme (BATS-R-US) for the global magnetosphere. In the authors’ scheme, BATS-R-US is used to set the magnetic field and boundary conditions for CRCM, and CRCM’s results feed back into the wider model.
The authors’ model takes more magnetospheric dynamics into account, and it runs more smoothly on powerful supercomputers than previous similar setups. Comparing their model against reference geomagnetic storms, the authors found that their model reproductions of the magnetosphere’s behavior compared well with satellite and ground-based observations.