回転球面上における減衰性2次元乱流の形態

Abstract

A series of numerical experiments is performed on two-dimensional turbulence on a rotating sphere of several rotation rate, with an attention to the pattern of flow field. In the non-rotating case, isolated coherent vortices emerge in the course of time development similarly to the planar two-dimensional turbulence.As the rotation rate increases, however, the temporal evolution of the flow field changes drastically and there appears an easterly circumpolar vortex in high latitudes. The flow field is then anisotropic at all the latitudes and elongated in the longitudinal direction.