An Exact Modon Solution in a Parabolically Sheared Zonal Flow

[摘要] An exact modon solution in a parabolically sheared zonal flow is constructed analytically in the equivalent barotropic system on a β plane. For a given parabolic shear, the propagation velocity of the modon is determined so that the potential vorticity becomes a linear function of the streamfunction. Circularity of the modon boundary is assumed. The obtained flow inside of the modon boundary has a high-over-low dipole structure in the central area, together with a low and high to the north and south thereof, respectively. The outside flow rapidly approaches the parabolically sheared zonal background flow as it recedes from the modon boundary.

[学科分类] 大气科学