In this paper, the nonlinear stationary waves forced by topography and diabatic heating are investigated. It is pointed out that (1) the nonlinear interaction of different stationary waves forced only by topography mi...In this paper, the nonlinear stationary waves forced by topography and diabatic heating are investigated. It is pointed out that (1) the nonlinear interaction of different stationary waves forced only by topography might form dipole blocking in the atmosphere, this might explain the dipole blocking appeared in the Pacific and Atlantic regions; (2) the dipole blocking could not be caused by the nonlinear interaction of the different stationary waves forced by the diabatic heating alone; (3) the nonlinear interaction of the diffferent stationary waves forced by both topography and diabatic heating could initiate dipole blocking in the atmosphere. In winter, the dipole blocking mainly occurs in the west regions of the Pacific and the Atlantic, and the heat source over the western part of the two oceans is advantageous to the formation of dipole blocking in the west of two oceans. However, in summer, the dipole blocking could be formed in the east part of the two oceans, and the heat source over the eastern part of two continents is favourable for the formation of dipole blocking in the east regions of two oceans.展开更多
In this paper, a new theory of blocking formation was proposed. The nonlinear Schrdinger equation satisfied by nonlear barotropic Rossby waves for the weak shear zonal flow was obtained by using the WKB method. It was...In this paper, a new theory of blocking formation was proposed. The nonlinear Schrdinger equation satisfied by nonlear barotropic Rossby waves for the weak shear zonal flow was obtained by using the WKB method. It was pointed out that when the Rossby wavenumbers sarisfied the relation: k/3<m^2<4k^2 (where k and m are the zonal and meridional wavenumbers respectively), the periodic Rossby wave in the atmosphere might produce the modulational instability and form the envelope Rossby solitary wave. Furthermore, the stream function field of the envelope Rossby solitary wave was calculated, and the structure derived here was similar to the dipole blocking in the atmosphere. On the other hand, we also pointed out that the dipole blocking might be caused through the Rossby wave modulational instability, moreover, the dipole blocking could persist for 25 days and disappear through energy dispersion of Rossby waves.展开更多
文摘In this paper, the nonlinear stationary waves forced by topography and diabatic heating are investigated. It is pointed out that (1) the nonlinear interaction of different stationary waves forced only by topography might form dipole blocking in the atmosphere, this might explain the dipole blocking appeared in the Pacific and Atlantic regions; (2) the dipole blocking could not be caused by the nonlinear interaction of the different stationary waves forced by the diabatic heating alone; (3) the nonlinear interaction of the diffferent stationary waves forced by both topography and diabatic heating could initiate dipole blocking in the atmosphere. In winter, the dipole blocking mainly occurs in the west regions of the Pacific and the Atlantic, and the heat source over the western part of the two oceans is advantageous to the formation of dipole blocking in the west of two oceans. However, in summer, the dipole blocking could be formed in the east part of the two oceans, and the heat source over the eastern part of two continents is favourable for the formation of dipole blocking in the east regions of two oceans.
文摘In this paper, a new theory of blocking formation was proposed. The nonlinear Schrdinger equation satisfied by nonlear barotropic Rossby waves for the weak shear zonal flow was obtained by using the WKB method. It was pointed out that when the Rossby wavenumbers sarisfied the relation: k/3<m^2<4k^2 (where k and m are the zonal and meridional wavenumbers respectively), the periodic Rossby wave in the atmosphere might produce the modulational instability and form the envelope Rossby solitary wave. Furthermore, the stream function field of the envelope Rossby solitary wave was calculated, and the structure derived here was similar to the dipole blocking in the atmosphere. On the other hand, we also pointed out that the dipole blocking might be caused through the Rossby wave modulational instability, moreover, the dipole blocking could persist for 25 days and disappear through energy dispersion of Rossby waves.
