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The solar activity cycle is successfully modeled by the flux transportdynamo, in which the meridional circulation of the Sun plays an important role.Most of the kinematic dynamo simulations assume a one-cell structure of themeridional circulation within the convection zone, with the equatorward returnflow at its bottom. In view of the recent claims that the return flow occurs ata much shallower depth, we explore whether a meridional circulation with such ashallow return flow can still retain the attractive features of the fluxtransport dynamo (such as a proper butterfly diagram, the proper phase relationbetween the toroidal and poloidal fields). We consider additional cells of themeridional circulation below the shallow return flow---both the case ofmultiple cells radially stacked above one another and the case of morecomplicated cell patterns. As long as there is an equatorward flow in lowlatitudes at the bottom of the convection zone, we find that the solar behavioris approximately reproduced. However, if there is either no flow or a polewardflow at the bottom of the convection zone, then we cannot reproduce solarbehavior. On making the turbulent diffusivity low, we still find periodicbehavior, although the period of the cycle becomes unrealistically large. Also,with a low diffusivity, we do not get the observed correlation between thepolar field at the sunspot minimum and the strength of the next cycle, which isreproduced when diffusivity is high. On introducing radially downward pumping,we get a more reasonable period and more solar-like behavior even with lowdiffusivity.

Is a deep one-cell meridional circulation essential for the flux transport Solar Dynamo?