Convergence Line Frontogenesis Type Rainstorm in Early Summer in the Eastern Section of the Yunnan-Guizhou Plateau
The convergence line frontogenesis is one of the causes of the rainstorm in the Eastern Section of the Yunnan-Guizhou Plateau,a typical Convergence Line Frontogenesis Type Rainstorm weather was analyzed which was happened from 11 to 12 May 2012,using 1 °× 1 ° reanalysis data of the NCEP/NCAR,sounding data and TBB data of FY-2E.The results show that it is a really typical Convergence Lines Frontogenesis Type Rainstorm in Guizhou,Coupling between mesoscale convergence line and shear line at low-level is the main reason for the development of convection.The mesoscale convective systems triggered due to convection move from west to east as a mesoscale clouds in the Satellite Images.The atmospheric stratification is unstable with hightemperature and high humidity in the process of the typical rainstorm all the time.The strong southwest airflow on 700 hPa and 850 hPa provides a better moisture transport condition for heavy rain produced.Positive vorticity and convergence are maintained on low-levels,negative vorticity and convergence divergence are maintained on high-levels.Frontogenesis function reveals the phenomenon of frontogenesis is existed obviously between the ground and 800 hPa,gradually decreases with height.horizontal divergence term F2 is main power factor causing Frontogenesis on the surface,the horizontal divergence termF2 and horizontal deformation term F3 have a significant positive contribution causing Frontogenesis on 850 hPa.Using theory of air blocks and method of kinematics to analyze convection,the trigger mechanism of convection is related of LFC,horizontal convergence intensity of synoptic-scale environmental field,convergence vertical height,convergence duration.
NETL
NSTL
万方数据
维普
