第一届未来大气科学论坛

The Dabie Vortex (DBV) is a critical mesoscale vortex frequently impacting central and eastern China, closely linked to heavy rainfall and severe convective weather. Under favorable conditions, DBV can spawn tornadoes, causing significant damage. However, the characteristics and formation mechanisms of tornadoes within DBV contexts remain poorly understood. This study investigates historical DBV activity and tornado events from 2006 to 2020. Results reveal that 19 tornadoes occurred amid DBV background, primarily concentrated in Henan, Hubei, Anhui, and Jiangsu provinces. DBV-related tornadoes accounted for up to 40.0% of total tornadoes in northern Anhui and over 20% in central and northern Jiangsu. Approximately 84.2% of these tornadoes occurred during the development and maintenance phases of DBV, with 73.7% forming in the southeastern quadrant. Compared to typhoon-induced tornadoes, DBV tornadoes exhibited higher convective available potential energy and stronger vertical wind shear, with larger Supercell Composite Parameter (SCP) but similar Significant Tornado Parameter (STP) values. Tornadoes during the DBV development phase occurred under weaker thermal but stronger dynamic instability, while those in the maintenance phase displayed the opposite pattern. These findings highlight that DBV can provide favorable thermal and dynamic environments for tornado formation, with significant variations across different DBV life stages.
 

Tornado,Dabie vortex,convection background