HR: 1400h
AN: SH23C-01    [Abstracts]
TI: Validation of a Global 3D-MHD Model for the Synoptic Solar Wind
AU: Cohen, O
EM: oferc@umich.edu
AF: Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143, United States
AU: Sokolov, i V
EM: igorsok@umich.edu
AF: Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143, United States
AU: Roussev, I I
EM: iroussev@ifa.hawaii.edu
AF: IFA, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, United States
AU: * Gombosi, T I
EM: tamas@umich.edu
AF: Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143, United States
AU: Manchester, W B
EM: chipm@umich.edu
AF: Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward St., Ann Arbor, MI 48109-2143, United States
AB: We developed a global 3D MHD model for the ambient solar. The model is driven by SOHO MDI magnetogram data, and is constrained by the empirical Wang-Sheeley-Arge (WSA) model. The WSA provides the distribution of the asymptotic solar wind speed; therefore it also provides the distribution of the kinetic energy. Assuming that far from the Sun the total energy is dominated by the energy of the bulk motion and assuming the conservation of the Bernoulli integral, we can trace the total energy along a magnetic field line to the solar surface. Since the gravitational energy on the surface is known, and the kinetic energy is negligible, we can obtain the distribution of the polytropic index on the surface of the Sun. By interpolating the value of the polytropic index to a spherically constant value of 1.1 at the source surface and to 1.5 at 5 Rs, we use this spatial distribution of the polytropic index in the energy equation to get a self-consistent, steady state MHD solution for the ambient, synoptic solar wind. We present a long-term comparison of the model results with observations at 1AU.
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
DE: 7509 Corona
DE: 7959 Models
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Joint Assembly