THE DISTRIBUTION OF KINETIC ENERGY IN CERTAIN STEADY BAROTROPIC CURRENTS

Abstract The spreading of an energy concentration superimposed on a uniform zonal current at a particular latitude, may be characterized by the complete disappearance of the perturbation at infinity. Under this condition the vorticity equation for a nondivergent barotropic atmosphere can be linearized exactly for steady-state motion and reduces to the well-known Helmholtz wave equation. Its solution then is quite general, and is not subjected to any restrictive condition of small perturbations. Two cases of “dispersion” were studied, the problem of the deflection of a zonal current and the problem of a zonal jet stream. In the first case the northward velocity component was prescribed as a boundary condition, in the second case the eastward velocity component. Due to the assumption of nondivergent flow, both components cannot be arbitrarily prescribed since they must satisfy the continuity requirement. Prescribing the distribution of either velocity component along a fixed meridian by a function with a pr...