Abstract
In order to discuss the general character of the perturbations of the westerlies produced by the mountains such as the Himalayas and the Rockies, we solve the stationary vorticity equation for the equivalent-barotropic level, taking into account topographical factors. It is shown that owing to the intensity of the general current, there are critical cases in which a single jet stream or two branches of it appear and these can be regarded as characterizing the normal state at the 500-mb level in January or June respectively. Especially the persistence of a ridge over the Sea of Okhotsk in the Baiu season, is thought to be produced in connection with the Himalayas. The effect of shear of the general current and friction upon the flow pattern are also discussed.
