Abstract: The beta plane approximation as it is usually derived suffers from the difficulty that it is only valid if the quasi-geostrophic approximation is made. It is not valid for the underlying momentum and continuity equations. ...

Abstract: In recent observational studies of atmospheric blocking it was found that the blocking region is characterized by relatively low and uniform values of the isentropic potential vorticity. It will be shown that the barotropic ...

Abstract: A numerical method is presented that allows one to obtain steady or zonally moving (i.e., form-preserving) solutions of the barotropic vorticity equation on a sphere. The solutions are characterized by nonlinear functional ...

Abstract: A simple model of the large-scale atmospheric circulation is studied. The model is based on the observation that the potential vorticity changes rapidly at the tropopause. This observation underlies the assumption that the ...

Abstract: An extension is given of the class of barotropic modon solutions on a sphere. In contrast to the previously obtained modons, the new solutions can be stationary in a solid-body rotation which is westerly. This property, ...

Abstract: A global version of the equivalent barotropic vorticity equation is derived for the one-layer shallow-water equations on a sphere. The equation has the same form as the corresponding beta plane version, but with one important ...

Abstract: It is shown that exact modon solutions of the barotropic vorticity equation on a sphere can be constructed. By using Legendre functions of real and complex degree and superimposing dipole and monopole streamfunctions, the ...

Abstract: The principle of maximum entropy is used to obtain energy and enstrophy spectra as well as average relative vorticity fields in the context of geostrophic turbulence on a rotating sphere. In the unforced-undamped (inviscid) ...

Abstract: A column of dry air in hydrostatic equilibrium is considered, bounded by two fixed values of the pressure, and the question is asked, what vertical temperature profile maximizes the total entropy of the column? Using an ...

Abstract: The influence of orography on the structure of stationary planetary Rossby waves is studied in the context of a contour dynamics model of the large-scale atmospheric flow. Orography of infinitesimal and finite amplitude ...