Precipitation and Convective Characteristics of Summer Deep Convection over East Asia Observed by TRMM

Abstract

Abstract This study examines precipitation and convective characteristics of summer deep convection for five distinct regions (plateau, foothill, lowland, south China, and ocean) in East Asia using 13 yr of Tropical Rainfall Measuring Mission (TRMM)-based precipitation features. Every region has its own unique features in terms of elevation, rainfall amount, and dynamic/thermodynamic environments. Results show that large, deep convective systems contribute the majority of precipitation totals over all regions except the plateau. Mixed-phase precipitation processes are more important in the south China and the lowland regions than in the foothill and ocean regions. The plateau region also shows substantial dependence upon mixed-phase processes, though the mixed-phase region has a smaller depth than the other regions. Most metrics indicate that the south China region has the most intense storms, followed by the lowland, plateau, foothill, and ocean regions. However, ice scattering signatures do show that the ocean region is more “intense” than the foothill and plateau regions. Deep convective systems over the plateau are the smallest and ocean systems the largest, while storms over the foothill, lowland, and south China regions are in between. Alternatively, convective intensity (storm size) in all regions strengthens (decreases) from early summer to midsummer. Both regional and intraseasonal variations in convective intensity and morphology are mainly modulated by changes in the meteorological environment, such as the convective available potential energy, height of neutral buoyancy, total water vapor, and vertical wind shear.