In the experiments, we clearly observe a plume-like flow for both viscosity regimes. This is in contrast to the images from GeoFlow I, which we relate with large-scale convective flow.

Several open issues have to be addressed:

• effects of depth dependence of gravity and thermal expansivity,
• specific planform of convection by numerical simulation and image processing,
• differences between further temperature-dependent properties of the 1-Nonanol in comparison with M5, e.g. dielectric expansion,
• impact of increasing viscosity ratio in numerical simulation for simple spherical model.

Therewith further experimental set points shall support the analysis of irregular fluid flow in the experiment, which occurs at very low Ra up to high Ra by means of

• highly resolved turn of the sphere, long-term observations of non-rotational
• cases with measurement time of n*15 min for specific temporal characteristics,
• variation of Vrms (6.5 : 6.51/2 : 1kV).