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| Titel |
Numerical modeling of fast CMEs from Sun to Earth |
| VerfasserIn |
Tibor Torok, Cooper Downs, Roberto Lionello, Jon A. Linker, Viacheslav S. Titov, Zoran Mikic, Pete Riley |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250083401
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| Zusammenfassung |
| Coronal mass ejections (CMEs) are the main driver of space weather
disturbances near Earth. The most severe disturbances are caused
by fast CMEs with coronal speeds in excess of 1000 km/s and magnetic
orientations favorable for interaction with the Earth's magnetosphere.
A proper assessment of the impact of CMEs from numerical simulations
requires the self-consistent modeling of both CME initiation and its
propagation through interplanetary space. Such simulations are very
challenging, in particular because of the enormous disparity of scales
involved. Here we present our recent attempts to model fast CMEs all
the way from Sun to Earth.
We first simulate the initiation and propagation of CMEs in the corona
using our "thermodynamic" MHD model, which includes empirical coronal
heating, thermal conduction, and radiation losses. After the initial
configuration, consisting of a large-scale dipole field and an idealized
active region, is relaxed to a steady-state solar wind solution, we
insert a flux rope in magnetic equilibrium into the active region and
trigger its eruption by imposing localized converging flows. We perform
a small series of simulations, varying the geometry and field strength
of the flux rope. The resulting CMEs produce a shock low in the corona
and reach peak velocities of up to 3000 km/s, after which they slow down
to constant propagation speeds of 1000 km/s or less. We then use our
recently developed heliospheric model to simulate the further propagation
to 1 AU for one of the model CMEs. |
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