Conclusion
"Convection is THE important transport mechanism in geophysical systems
"for moderate heat differences systems exhibit a stationary flow
"depending on the magnitude of the Prandtl number the flows are becoming time-dependent
"for low-Pr. flow the velocity fields have a strong toroidal component
"effect like volumetric heating break the symmetry between up- and down-wellings
"most geophysical flows are in a regime where the flows are chaotic