Statistical analysis of mesoscale convective systems over
Yangtze-Huaihe basin in summer
LIU Ruixiang1,2, DING Zhiying1, SUN Lingguang3, HUANG Haibo1
(1. College of Atmospheric Sciences , Nanjing University of Information Science & Technology, Nanjing 210044；2. Lianyungang
Meteorological Bureau of Jiangsu Province, Lianyungang 222000；3. Heihe Meteorological Bureau of Heilongjiang Province, Heihe 164300)
The mesoscale convective systems(MCSs) over Yangtze-Huaihe basin were classified into mesoscale convective complex(MCC), persistent elongated convective system(PECS), meso-β circular convective system(MβCCS) and meso-β elongated convective system (MβECS) based on the FY-2D geostationary satellite blackbody temperature data during June to August from 2007-2013. The statistical characteristics of different kinds of MCS cases were analysed. The results indicate that PECS and MβECS occur more frequently than MCC and MβCCS, accounting for 62.2%. There are most MCSs in July while the mean area of mature MCSs in June ranks first, and the average minimum blackbody temperature of mature MCSs is about -76℃. The peak time for MCS initiation is around 14:00-17:00 BT while most MCSs mature in the period of 17:00-19:00 BT and dissipate during 18:00-23:00BT, however, it differs for diverse types. Most MCS cases which influence Yangtze-Huaihe basin generate in the land while rarely in the sea. Eastward, northeastward and southeastward are the three main moving directions for MCSs, with a total percentage of about 73.1%. The moving distance of MCS case is closely related to its lifetime and themain distance is 1~5 latitude and longitude degrees, accounting for 64.6%.