两次早春暴雪过程的对比分析  

Comparative Analyses on Two Early Spring Snowstorm Processes

作　　者：周雪松[1,2] 杨成芳[2] 孙兴池[2] 

机构地区：[1]南京大学中尺度灾害性天气教育部重点实验室/大气科学学院,江苏南京210093 [2]山东省气象台,山东济南250031

出　　处：《高原气象》2013年第2期446-455,共10页Plateau Meteorology

基　　金：国家自然科学基金项目(41175044);山东省气象局重点课题(2012SDQXZ04)共同资助

摘　　要：利用常规资料、区域气象自动站、卫星云图、多普勒天气雷达和闪电定位资料等,对2010年和2011年山东早春出现的两次暴雪天气过程进行了对比分析,重点研究了暴雪的对流性和成因。结果表明,低涡(切变线)、低空急流、地面气旋(倒槽)等是暴雪的主要影响系统;高空和地面天气系统在时间和空间配置上的差异是造成暴雪对流性不同的关键因素。红外云图能很好地反映暴雪天气过程对流性的强弱;多普勒天气雷达可清楚地识别出两次过程的中尺度结构。南北对称的垂直速度对是早春暴雪的重要特征;对流层低层逆温层和暴雪前期爆发性增暖是造成"雷打雪"的重要因素;物理量诊断的对流不稳定存在与否是区别"雷打雪"和常规暴雪的重要标志;垂直风切变在"雷打雪"暴雪过程中发挥重要作用。Two heavy snowstorm processes in Shandong Province in 2010 and 2011 were studied, especially on the convective characteristic and cause using the convention data, region automatic observation, satellite cloud image, Doppler radar and lightning orientation instrument, and so on. The results show that, the affecting system, such as vortex （shear line）, low-level jet and the surface cyclone （inverted trough） play an important role in heavy snowfall; the difference of upper level and surface weather systems in temporal and spatial configurations causes the difference of the convective characteristic. It can well re- flect convective intensity of heavy snowstorm in infrared cloud image. Doppler weather radar can clearly i- dentify the mesoscale structures in the two processes. North-south symmetry of the vertical speed was the important feature of early spring snow. The lower troposphere temperature inversion and pre-warming caused the ＇thunder snow＇. Convective instability of physical diagnosis is an important symbol of conventional blizzard. The vertical wind shear in the ＇thunder snow＇ plays an important role.

关 键 词：早春暴雪 中尺度结构 对流不稳定 

分 类 号：P458[天文地球—大气科学及气象学]