Abstract

Magnetic buoyancy, believed to occur in the solar tachocline, is both an important part of large-scale solar dynamo models and the picture of how sunspots are formed. Given that in the tachocline region the ratio of magnetic diffusivity to thermal diffusivity is small it is important, for both the dynamo and sunspot formation pictures, to understand magnetic buoyancy in this egime. Furthermore, the tachocline is a region of strong shear and such investigations must involve structures that become buoyant in the double-diffusive regime, which are generated entirely from a shear flow.

In this talk, I will briefly review my initial 3D-calcuations that showed that a double diffusive buoyancy instability was possible in the tachocline. However, as I will discuss, it became apparent that a reduced quasi-two dimensional model needed to be considered. I will then present this model together with the findings from the research.