Layer formation in rotating and stratified flows

We present a numerical study of layer formation in forced, rotating, stably stratified Boussinesq flows. We focus on parameter regimes with buoyancy frequency $N$ and rotation frequency $f$ chosen such that the timescales $1/N$ and $1/f$ are at least as fast as the nonlinear timescales. The aspect-ratio of the domain is $\delta = H_d/L_d$ where $H_d$ and $L_d$ are the domain height and width respectively. Two sets of calculations are studied at small, nearly fixed Froude number $Fr = U/(H N) \approx 0.002$ where $H$ is fixed at one-quarter of $H_d$ and $U$ is the characteristic forcing based velocity scale. The first set fixes $\delta = 1$ with $N/f$ values ranging from 1 to 32. The second set fixes the Burger number $Bu = \delta N/f = 1$ with aspect ratio $\delta = H_d/L_d$ ranging from 1 to 1/16. We show that both rotation rate and domain aspect-ratio conspire to set the scale and structure of the layers formed in the flows.