Mesoscale Convective System：From Interannual and Decadal Variability to Climatic Responses

A Mesoscale Convective System (MCS) is a cloud system composed of multiple convective systems. Its horizontal precipitation scale lies between that of individual thunderstorms and mid-latitude cyclones, with a temporal scale usually lasting several hours or longer. MCSs appear in various forms and are often associated with severe, high-impact weather events. Influenced by systems like the Tibetan Plateau and the East Asian monsoon, MCSs in China exhibit many unique characteristics, significantly affecting regional hydrological cycle, heavy rainfall events, and flooding disasters in China. Research on MCSs holds considerable scientific significance and practical value, playing a crucial role in improving weather forecasting capabilities. This paper reviews the research achievements and progress made by Chinese scholars in the field of MCSs. It introduces the history of MCS observation and research in China, from early observational experiments to recent technological advancements and numerical simulation studies, showcasing significant accomplishments in the observation and mechanistic understanding of MCSs in China. The paper focuses on the interannual and decadal variability of MCSs, analyzing the spatiotemporal distribution characteristics of MCSs in different regions of China and their contributions to precipitation changes, as well as the role of long-term variability in regulating MCSs. Furthermore, the paper summarizes on-going research progress on the response of MCSs to climate change, highlighting the impact of global warming on the frequency and intensity of MCSs, and discusses the effects of human activities, such as aerosol emissions and urbanization on MCSs. Finally, the paper explores potential future development directions for MCS research.