Conventional observation data,precipitation data from regional automatic stations,1°×1° NCEP reanalysis data and TBB pictures of FY-2C geostationary meteorological satellite as well as Doppler radar,etc...Conventional observation data,precipitation data from regional automatic stations,1°×1° NCEP reanalysis data and TBB pictures of FY-2C geostationary meteorological satellite as well as Doppler radar,etc.were utilized to analyzing the heavy precipitation process in Hunan Province from June 8 to 10.The results indicated that this heavy precipitation process was caused under the condition of western Pacific subtropical high jumped northward and fell southward rapidly,maintained and swung the shear line of low and middle-level atmosphere over long periods,and configurated temperature-moisture energy.Through analysis we found that precipitation period and precipitation area had a good corresponding to radar product and satellite TBB image,the high potential pseudo-equivalent temperature(θse) of low level and high convergence available potential energy(CAPE) area as well as ascending area of strong convergence.With the extension of effective forecasted period,the forecast location of T639 and EC on the western ridge points of western Pacific subtropical high became more and more easterly and the intensity became weaker and weaker,which had some deviations for forecasting heavy precipitation area.展开更多
Seasonal variability regarding the nature of precipitation and the activity of cumulus convection during the 1991 Meiyu season of Changjiang-Huaihe River Basin(Jianghuai)has been investigated by calculating apparent h...Seasonal variability regarding the nature of precipitation and the activity of cumulus convection during the 1991 Meiyu season of Changjiang-Huaihe River Basin(Jianghuai)has been investigated by calculating apparent heat source/apparent moisture sink and analyzing TBB(cloud-top blackbody radiation temperature)data.It is found that three periods of strong ascending motion during the Meiyu season lead to three episodes of heavy rain,and the latent heat due to the precipitation is of the sole heat source of the atmosphere.The nature of precipitation shows distinct seasonal variability,from frontal precipitation of the first episode to the extremely strong convective precipitation of the third episode.TBB field of East Asia may well reflect not only the intensity of convection and rainfall,but also the movement of rain belt and convection belt.In the whole Meiyu season.convection belt mainly stays in Jianghuai.but may shift within the domain of East Asia.Its locating in Jianghuai or not determines the maintenance or break of Meiyu.In the third episode,the narrow convection belt over Jianghuai is mainly caused by southwest monsoon which takes moist and convective atmosphere from tropical ocean.展开更多
文摘Conventional observation data,precipitation data from regional automatic stations,1°×1° NCEP reanalysis data and TBB pictures of FY-2C geostationary meteorological satellite as well as Doppler radar,etc.were utilized to analyzing the heavy precipitation process in Hunan Province from June 8 to 10.The results indicated that this heavy precipitation process was caused under the condition of western Pacific subtropical high jumped northward and fell southward rapidly,maintained and swung the shear line of low and middle-level atmosphere over long periods,and configurated temperature-moisture energy.Through analysis we found that precipitation period and precipitation area had a good corresponding to radar product and satellite TBB image,the high potential pseudo-equivalent temperature(θse) of low level and high convergence available potential energy(CAPE) area as well as ascending area of strong convergence.With the extension of effective forecasted period,the forecast location of T639 and EC on the western ridge points of western Pacific subtropical high became more and more easterly and the intensity became weaker and weaker,which had some deviations for forecasting heavy precipitation area.
基金This work was supported jointly by the project of Sino-Japan Cooperation Study on Asia Monsoonthe National Natural Science Foundation of China.
文摘Seasonal variability regarding the nature of precipitation and the activity of cumulus convection during the 1991 Meiyu season of Changjiang-Huaihe River Basin(Jianghuai)has been investigated by calculating apparent heat source/apparent moisture sink and analyzing TBB(cloud-top blackbody radiation temperature)data.It is found that three periods of strong ascending motion during the Meiyu season lead to three episodes of heavy rain,and the latent heat due to the precipitation is of the sole heat source of the atmosphere.The nature of precipitation shows distinct seasonal variability,from frontal precipitation of the first episode to the extremely strong convective precipitation of the third episode.TBB field of East Asia may well reflect not only the intensity of convection and rainfall,but also the movement of rain belt and convection belt.In the whole Meiyu season.convection belt mainly stays in Jianghuai.but may shift within the domain of East Asia.Its locating in Jianghuai or not determines the maintenance or break of Meiyu.In the third episode,the narrow convection belt over Jianghuai is mainly caused by southwest monsoon which takes moist and convective atmosphere from tropical ocean.
