[Objective] The research aimed to analyze a strong convective weather process in Beihai in summer. [Method] By using Micaps conventional data and the single station site information of Beihai, radar data, a strong con...[Objective] The research aimed to analyze a strong convective weather process in Beihai in summer. [Method] By using Micaps conventional data and the single station site information of Beihai, radar data, a strong convective weather process in Beihai City in August, 2010 was analyzed. [Result] 850 and 700 hPa cyclonic low-pressure circulation in the north of Vietnam and Beibu Gulf coast was favorable for the transportation of Bengal Bay southwest airflow, which provided the sufficient water vapor condition for the strong precipitation. The interaction of weak cold air and southeast warm wet airflow was the main cause of the strong rainfall process. The falling zone of strong precipitation related to the water vapor convergence. The maintenance of water vapor flux divergence field in southeast-northwest direction was favorable for the duration of strong precipitation in the south of Guangxi. Before the strong precipitation, the positive and negative vorticity in the high and low levels in Beihai station both abruptly strengthened, which was very favorable for generating the convection. The vertical velocity in the strong precipitation process turned from the positive value at the beginning into the negative value as the height variation. The turning had the indicated and early-warning roles on the generation of strong convective weather. [Conclusion] The research provided the theory basis for the strong convective weather forecast in Guangxi coast in summer.展开更多
Based on diagnostic results,a numerical study is made of the processes of Australian cold air activity affecting East Asian summer monsoon by using Kuo-Qian P-σ incorporated coordinate five-layer primitive equation s...Based on diagnostic results,a numerical study is made of the processes of Australian cold air activity affecting East Asian summer monsoon by using Kuo-Qian P-σ incorporated coordinate five-layer primitive equation spherical band model.Analysis is done of the response to the Southern Hemisphere circulation with and without cold air activity in Australia of the flow,rainfall and diabatic heating fields in the monsoon area of Asia,especially,East Asia,with special attention to the intensification and northward march of the monsoon due to the activity.It is found that the processes for the effect transmission are very analogous to the meridional propagation of quasi-40-day oscillation,together with the meridional wind disturbance showing south-north travel and the flow/rainfall fields exhibitirg corresponding movement in this direction,only with a 12-day lag.展开更多
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences[grant numbers XDA23090102]the National Natural Science Foundation of China[grant numbers 42175078 and 42075040]+1 种基金the Health Meteorological Project of Hebei Province[grant number FW202150]the National Key Research and Development Program of China[grant number 2018YFA0606203].
文摘[Objective] The research aimed to analyze a strong convective weather process in Beihai in summer. [Method] By using Micaps conventional data and the single station site information of Beihai, radar data, a strong convective weather process in Beihai City in August, 2010 was analyzed. [Result] 850 and 700 hPa cyclonic low-pressure circulation in the north of Vietnam and Beibu Gulf coast was favorable for the transportation of Bengal Bay southwest airflow, which provided the sufficient water vapor condition for the strong precipitation. The interaction of weak cold air and southeast warm wet airflow was the main cause of the strong rainfall process. The falling zone of strong precipitation related to the water vapor convergence. The maintenance of water vapor flux divergence field in southeast-northwest direction was favorable for the duration of strong precipitation in the south of Guangxi. Before the strong precipitation, the positive and negative vorticity in the high and low levels in Beihai station both abruptly strengthened, which was very favorable for generating the convection. The vertical velocity in the strong precipitation process turned from the positive value at the beginning into the negative value as the height variation. The turning had the indicated and early-warning roles on the generation of strong convective weather. [Conclusion] The research provided the theory basis for the strong convective weather forecast in Guangxi coast in summer.
基金National Natural Science Foundation of ChinaState Meteorological Administration Monsoon Research Funds
文摘Based on diagnostic results,a numerical study is made of the processes of Australian cold air activity affecting East Asian summer monsoon by using Kuo-Qian P-σ incorporated coordinate five-layer primitive equation spherical band model.Analysis is done of the response to the Southern Hemisphere circulation with and without cold air activity in Australia of the flow,rainfall and diabatic heating fields in the monsoon area of Asia,especially,East Asia,with special attention to the intensification and northward march of the monsoon due to the activity.It is found that the processes for the effect transmission are very analogous to the meridional propagation of quasi-40-day oscillation,together with the meridional wind disturbance showing south-north travel and the flow/rainfall fields exhibitirg corresponding movement in this direction,only with a 12-day lag.
