Title: Convective Precipitation in South China: Mesoscale Convective Systems and Tropical Cyclones
Speaker: Ang Zhou (Nanjing University)
Abstract: South China is among the world’s most precipitation-rich regions, where annual rainfall is largely concentrated in two distinct flood seasons. The pre-flood season (April–June) is dominated by mesoscale convective systems (MCSs), which develop rapidly and often have strong local impacts, frequently producing regional rainstorms and occasionally severe convective hazards such as hail and damaging winds. The post-flood season (July–September) is primarily influenced by tropical cyclones and their associated circulation systems, featuring high-intensity, long-duration, and wide-ranging rainfall that can result in substantial casualties and economic losses.
The region’s complex physical geography and intense human activities further increase the multiscale complexity of precipitation. Key contributing factors include sea–land thermal contrasts that drive sea-breeze circulations, orographic lifting over mountainous terrain, urban heat-island effects and changes in surface roughness and friction, and anthropogenic aerosol emissions. These factors can modulate rainfall intensity, frequency, and spatiotemporal distribution.
This talk focuses on MCSs and tropical-cyclone-related precipitation in South China, summarizing their spatiotemporal characteristics and discussing associated disaster mechanisms and key controlling factors