Comprehensive properties of non-penetrating and penetrating deep convection precipitation in summer over the Tibetan Plateau derived from GPM observations

Abstract

The spatial-temporal distribution, drop size distribution and their associated thermal structure as well as the tropopause anomalies of non-penetrating and penetrating deep convection precipitation in summer of 2014–2021 over the Tibetan Plateau are explored using GPM observations, ERA5 reanalysis data and topographic data in this study. The result shows that frequencies and intensities of non-penetrating deep convection precipitation are generally larger than those of penetrating deep convection precipitation. The storm tops of non-penetrating and penetrating deep convection are approximately 15–16 km and 18–19 km respectively, whereas the corresponding lapse rate tropopause heights for both types of deep convection are similar (about 17.4 km). The radar reflectivity decreases with height and the maximum appears near the surface. Latent heat release of non-penetrating deep convection is largely confined in the lower troposphere, while latent heating of penetrating deep convection is higher. Moreover, rain drop concentration of non-penetrating deep convection distributes uniformly (5–15 km) and particle size is large (2.0–2.5 mm) near the surface. In contrast, penetrating deep convection particles concentrate below 10 km and near the storm top (19–20 km), with small size (1.0–1.5 mm). Furthermore, there are evident differences in thermal structure during non-penetrating and penetrating deep convection process over the Tibetan Plateau. Notably, slight net warming anomaly occurs above tropopause during penetrating deep convection due to subsidence from divergent flow. Moistening anomaly is more significant below 11 km following non-penetrating deep convection. However, slight dehydration appears near the tropopause after penetrating deep convection. Descending tropopause and increasing CAPE before penetrating deep convection are more significant and conducive to penetrating. These results suggest macro-micro features of non-penetrating and penetrating deep convection and interaction between two types of deep convection and thermal structure over the Tibetan Plateau.