The Related Researches of the Vortex Sourceof Southwest China Vortex Weather System

The Southwest China vortex (SWCV) is that under the special terrain and circulation conditions of the Tibetan Plateau (TP), a meso-α-scale cyclonic low system with 300-500km horizontal scale at 700hPa or 850hPa in Southwest China. Being the important influencing system for the large area heavy precipitation in China summer half year, it is the second rainstorm weather system in China after typhoon in the intensity, frequency, and range of the caused rainstorms. So, SWCV and its weather influences are one of the main directions in Plateau Weather Science. And the research on the vortex source of SWCV has been always the key point of close attention.

The new related progresses in researches of the vortex source of SWCV system are reviewed for the last 10 years. In particular，it is recognized that because of the multi-scale effects between the topography and circulation，the vortex source of SWCV has the multi-scale characteristic of its distribution, and there are obviously differences between the structure、evolution、cause and influence of SWCV with the different vortex sources. The vortex sources of SWCV have closely connection each other. The upper-reach vortex sources such as Jiulong&Xiaojin have an important effect on the lower-reach vortex sources such as the Basin. The“effect of upper-reach vortex source”of SWCV, atmospheric gravity wave connecting with the complex topography，internal atmospheric process induced by precipitation, and the anomalous influences of East Asia monsoon are also the formation mechanisms for the vortex source of SWCV. And the formation of SWCV is mainly determined by the speed of incoming airflow in the direction of the main axis of the Hengduan Mountains. The formation vortex source of SWCV is mainly determined by the relative position of the incoming airflow in the windward area and the main axis of the Hengduan Mountains.

But, for research on the vortex source of SWCV, there are some problems such as being weaker in fine observation and basic data，being unknown for the multi-scale structures of the vortex source and its evolution, being not deep to understand the formation cause of different vortex sources and being incomplete in study of the SWCV evolutions and its effects of different vortex sources.