Statistic characteristics of severe convective storm during Warm-Season in the Beijing-Tianjin region and its vicinity

This study analyzed the climatological characteristics of severe convective storms in the Beijing and Tianjin region and its vicinity based on the Doppler radar data of Tanggu during May–August of 2003–2007. The climatological characteristics, e.g. storm area, volume, top height, max reflectivity, life time and motion, are analyzed. The results include: 75% of all storms in the Beijing-Tianjin region last no more than 30 minutes, and most storms have a volume less than 400 km³; most storms move from southwest to northeast while the speed is between 10–30 km/h; the mean storm top height is about 6 km, but some strong convective storms can have a top height larger than 15 km; finally, storm area and volume have a similar geographical distribution character showing increasing trends from west to east. Compared with the statistic results based on the conventional surface meteorological observations, the results based on the radar data can present not only 3D spatial statistic results of convective storms (e.g., volume and top height), but also the quantitative climatological characteristics, such as the lifetime and speed distributions. These statistical results are useful for studying the climatic characteristics of convective storms in the Beijing-Tianjin region and its vicinity. Supported jointly by the National Natural Foundation of China (Grant Nos. 40575014, 40305004 and 40875019), Open Research Project of State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences (Grant No. 2008LASW-A02), National Basic Research Program of China (Grant No. 2004CB418300) and Ph.D. Programs Foundation of the Ministry of Education of China (Grant No. 20040001008)