Chengdu University of Information Technology
Abstract: Based on the atmospheric motion equations and divergence equation, this paper analyze and discuss the stability of the disturbance involved with the transverse shear line (TSL) over the Tibetan Plateau (TP) and the dynamical mechanism of the Tibetan Plateau vortex (TPV) induced by the TSL then verify it by ERA-interim reanalysis data. It is concluded that the TSL is the important background field of TPV. The TPV induced by the transport of water vapor which located in the south of the TSL is associated with the adjustment of divergence field caused by the unbalanced of atmosphere, which is favorable for the formation of TPV in the position where the convergence is enhanced, the center of the TPV corresponds to the positive center of unbalanced items and the periphery of the TPV is negative area of unbalanced items. The area where the large negative value of unbalanced items coincides with the vapor convergence can indicate the location of precipitation. When the southwest winds increased and move toward the east or northeast, or when there is a negative center area of unbalanced item downstream of the TPV, the vortex moves to the same direction. If there is a cyclonic circulation in the TP and the center of the cyclonic circulation corresponds to the positive center of the unbalanced items, it is conducive to the formation of TPV; further, when the center of the vortex corresponds to the unbalanced positive center and the value of that increase continuously, it is also favorable for the development of the TPV.