A Review of Studies on Torrential Rain During Pre-Summer Flood Season in South China Since the 1980's

A review is the study on torrential rain during pre-summer flood season in South China since the 1980's to mainly introduce the weather background,such as the large-scale circulation in mid-high latitudes,the subtropical high,the South Asia high and the subtropical westerly jet stream during the period of pre-summer flood season in South China,to point out the role of Asian summer monsoon,cold air activities from south hemisphere and cross-equatorial air flows,to present the main weather systems and their characteristics,the formation mechanism of the lower level jet(LLJ) in South China and in the north part of South China sea,its relation with the heavy rain and its role to trigger off the heavy rain,to elucidate the formation mechanism and physic image of mesoscale convective systems triggering off the heavy rain,and the effects of topography,land-sea difference and underlaying surface on the torrential rain,and to introduce the main cloud microphysics during the torrential rain.Lastly,a multi-scale physical concept model about the torrential rain formation in South China is concluded based on above studies and scientific issues needed to be further studied are put forward.