Hysteretic transitions between quasi-two-dimensional flow and three-dimensional flow in forced rotating turbulence

Conflict between formation of a cyclonic vortex and isotropization in forced homogeneous rotating turbulence is numerically investigated. It is well known that a large rotation rate of the system induces columnar vortices to result in quasi-two-dimensional (Q2D) flow, while a small rotation rate allows turbulence to be three-dimensional (3D). It is found that the transition from the Q2D turbulent flowto the 3D turbulent flowand the reverse transition occur at different values of the rotation rates. At intermediate rotation rates, bistability of these two statistically steady states is observed. Such a hysteretic transition is also observed for variations of the amplitude of an external force.