摘要
利用2007—2015年济南市区及历城区自动气象观测站的逐小时降水量资料,以及常规高空、地面观测资料,统计了198次短时强降水过程的范围和强度特征,年际、月际变化特征,按照短时强降水发生时的天气形势和影响系统,分为切变线型、低槽冷锋型、西风槽型、冷涡型、台风外围型及无系统型6类,并分析了不同类型和不同范围短时强降水的关键环境参量。研究表明:短时强降水的强度与范围有较好的相关性,7月中旬—8月中旬出现强降水的次数最多;切变线型短时强降水发生范围与强度分布最广,7、8月的低槽冷锋型过程极易造成大范围高强度降水;地面露点(Td)、850 h Pa假相当位温(θse)、对流有效位能(CAPE)以及暖云层厚度能较好地区分不同范围的短时强降水过程。在天气分型的基础上,结合不同降水范围和不同降水类型环境参量箱线图与阈值表,可为济南市区短时强降水的预报提供有价值的参考。
The characteristics of scopes,intensities,yearly and monthly variation in short-duration heavy rainfalls were analyzed by using the hourly precipitation data of automatic weather stations in Jinan and Licheng district and the conventional high-level and surface observation data from 2007 to 2015. The short-time heavy rainfalls were classified into six types,including shear-line,cold-front,upper-trough,coldvortex,typhoon-periphery and non-system types,according to the synoptic environment and the influence systems. Key environmental parameters of short-time heavy rainfalls were also discussed. The results show that there was a close correlation between the scopes and intensity of short-duration heavy rainfalls,and short-duration rainfalls occurred most frequently from mid-July to mid-August. The shear-line type heavy rainfalls occurred t with large scope and strong intensity,while the cold-front type one could cause severe precipitation in July and August.Different types of short-time rainfalls could be classified by the surface dew point,850 h Pa θse,CAPE,and warm cloud thickness. Combined with the box-plots and thresholds of environment parameters in different scopes and types of precipitation,the synoptic classification could provide valuable reference for the short-duration heavy rainfall forecasting in Jinan urban district.
出处
《海洋气象学报》
2017年第3期109-116,共8页
Journal of Marine Meteorology
基金
山东省气象局气象科学技术研究项目(sdjn2016-04)
关键词
短时强降水
天气分型
预报概念模型
关键环境参量
short-duration heavy rainfall
synoptic classification
forecast conceptual models
key environmental parameters
