Large-scale and mesoscale analyses are made for extremely heavy rain (EHR) and meso-β scale low vortex (MSLV) in Jiading District of Shanghai Municipality during 6-7 July 2001.It is shown that the EHR forms in the si...Large-scale and mesoscale analyses are made for extremely heavy rain (EHR) and meso-β scale low vortex (MSLV) in Jiading District of Shanghai Municipality during 6-7 July 2001.It is shown that the EHR forms in the situation of northern westerly trough linking together with southern inverted typhoon trough at northwest side of the West Pacific Ocean subtropical high. Numerical simulation is made using a 21-layer improved REM (regional η coordinate model) for this course.The results show that the precipitation forms earlier than MSLV.and the strong convergence in wind velocity mate (WVM) triggers the strong precipitation.The formative reasons of WVM.especially the weak wind velocity center are discussed,and the formative mechanisms of the MSLV and EHR are discussed using high spatial and temporal resolution model- output physical fields.The results show that the heavy rain releases latent heat and warms the air column,and enhances the low level positive vorticity that existed before.Then it causes the formation of MSLV.There is a positive feedback mechanism between low vortex and precipitation,so CISK must be an important mechanism.展开更多
[Objective] The aim was to analyze the process and reason of the extreme heavy rainfall on June 15,2011 in Cold Lake in Qinghai.[Method] The weather,physical field and satellite of one extreme heavy rain in the cold l...[Objective] The aim was to analyze the process and reason of the extreme heavy rainfall on June 15,2011 in Cold Lake in Qinghai.[Method] The weather,physical field and satellite of one extreme heavy rain in the cold lake in Qinghai were expounded.[Result] The formation of the loop 'crooked neck' of high pressure,which on the one hand posed a typical situation in the circulation of heavy precipitation in Qinghai,and on the other hand,formed the southwest,southeast of the two water vapor transport in air,in addition to the small groove from the trough of Lake Balk hash and the split vortex plateau,resulted into the extreme heavy rainfall in Cold Lake.The presence of thermal low pressure 700 hPa was conducive to the accumulation of low energy and low-level moisture transport from the Qinghai region to the south of Qaidam Basin.[Conclusion] The resulting process was mainly due to heavy rain in the lower troposphere convergence,high-level divergence,high humidity areas and a strong vertical upward motion.展开更多
基金supported by the Air Force Foundation under Grant No.KJ99099
文摘Large-scale and mesoscale analyses are made for extremely heavy rain (EHR) and meso-β scale low vortex (MSLV) in Jiading District of Shanghai Municipality during 6-7 July 2001.It is shown that the EHR forms in the situation of northern westerly trough linking together with southern inverted typhoon trough at northwest side of the West Pacific Ocean subtropical high. Numerical simulation is made using a 21-layer improved REM (regional η coordinate model) for this course.The results show that the precipitation forms earlier than MSLV.and the strong convergence in wind velocity mate (WVM) triggers the strong precipitation.The formative reasons of WVM.especially the weak wind velocity center are discussed,and the formative mechanisms of the MSLV and EHR are discussed using high spatial and temporal resolution model- output physical fields.The results show that the heavy rain releases latent heat and warms the air column,and enhances the low level positive vorticity that existed before.Then it causes the formation of MSLV.There is a positive feedback mechanism between low vortex and precipitation,so CISK must be an important mechanism.
文摘[Objective] The aim was to analyze the process and reason of the extreme heavy rainfall on June 15,2011 in Cold Lake in Qinghai.[Method] The weather,physical field and satellite of one extreme heavy rain in the cold lake in Qinghai were expounded.[Result] The formation of the loop 'crooked neck' of high pressure,which on the one hand posed a typical situation in the circulation of heavy precipitation in Qinghai,and on the other hand,formed the southwest,southeast of the two water vapor transport in air,in addition to the small groove from the trough of Lake Balk hash and the split vortex plateau,resulted into the extreme heavy rainfall in Cold Lake.The presence of thermal low pressure 700 hPa was conducive to the accumulation of low energy and low-level moisture transport from the Qinghai region to the south of Qaidam Basin.[Conclusion] The resulting process was mainly due to heavy rain in the lower troposphere convergence,high-level divergence,high humidity areas and a strong vertical upward motion.