Preferred Perturbations of Growth in the Barotropic Atmosphere and Dynamics of Teleconnection
正压大气有利发展扰动型与遥相关型的建立

The goal of this study is to determine whether the generation of teleconnection patterns can resultsolely from the internal barotropic processes of the zonally varying climatoloical flow in the northern summer. The results of analysis of normal modes indicate that the growth rate of unstable normal modes is insufficient to explain the generation of realistic teleconnection patterns. Then, a concept of preferred Perturbation of growth is introduCed. An approach to find the prefeed perturbances of growth is described in detail. The results of calculations show that the amplification rate of the leading preferred perturbations of growth is consistent with that of realistic teleconnection patterns. Moreover,they evolve into the structure of realistic teleconnection patterns. The preferred perturbation of growth possesses highly localized spatial structures with the wavetrain appearance, most of them are localized to the south of regions of the jet cores. It is suggested that at least some of teleconnection patterns can form as a consequence of internal barotiopic processes of the zonally asymmetrical basic state , but de pend on the preferred perturbations of growth, which have larger growth rate than that of unstable normal modes.