8822287 Roberts The principal investigator will study nonlinear convection arising in a horizontal layer of electrically conducting fluid. The layer is heated from below, cooled from above, is rotating about the vertical, and is permeated by an applied horizontal magnetic field. This represents an idealization of conditions that arise in nature, e.g. in the solar convection zone. The unusual feature of such a system, the feature that motivates this project, consists of theoretical and observational hints that the pattern of convection will in general vary with height. This possibility will be studied in detail in this project.