b-PLANE MAGNETOHYDRODYNAMIC TURBULENCE IN THE SOLAR TACHOCLINE
نویسندگان
چکیده
This Letter discusses the role of a weak toroidal magnetic field in modifying the turbulent transport properties of stably stratified rotating turbulence in the tachocline. A local two-dimensional b-plane model is investigated numerically. In the absence of magnetic fields, nonlinear interactions of Rossby waves lead to the formation of strong mean zonal flows. However, the addition of even a very weak toroidal field suppresses the generation of mean flows. We argue that this has serious implications for angular momentum transport in the lower tachocline. Subject headings: MHD—Sun: interior— Sun: magnetic fields— turbulence
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