Observed Large‐Scale Structures and Diabatic Heating Profiles of Precipitation Over the Tibetan Plateau and South China

Abstract

AbstractThis study investigates and compares large‐scale dynamic and thermodynamic structures of precipitation over the Tibetan Plateau (TP) and South China (SC). Vertical velocity, temperature and moisture advection, apparent heat source Q1 and apparent moisture sink Q2 are analyzed for strong, moderate, and light/no‐rain based on the measurements. The principal findings are as follows. (1) Both regions showed the strongest upward motion at around 400 hPa for strong and moderate rainfall, but the intensity of upward motion in SC was twice that of the TP. (2) Horizontal temperature advection over the TP showed advective warming in the lower troposphere and advective cooling in the upper troposphere, but this advection over SC was weaker and had a different vertical structure. Moreover, the strong‐rain horizontal temperature advection was the strongest over the TP but the weakest over SC. (3) The moisture advection over the TP reached its maximum at around 400 hPa, showing a one‐peak structure; while that over SC was stronger in the mid‐to‐low troposphere, showing a multi‐peak structure. (4) The Q1 profiles of the three rain categories in the TP were top‐heavy, with two heating peaks in the mid‐to‐upper troposphere. In contrast, the Q1 profiles in SC only had a heating peak in the middle troposphere. Correlations between the vertically integrated <Q1> and <Q2> were significant in SC but weakened in the TP. (5) Diurnal cycles of large‐scale structures in the TP were strong from the late afternoon to early morning, while those in SC were strong in the afternoon.