成都市冰雹的时空变化与地形特征分析

Spatial-Temporal Variations and Topographic Characteristics of Hails in Chengdu

利用成都市1984—2012年冰雹日志数据,分析了成都市近30年冰雹发生的时间变化、空间分布和地形特征。结果表明:成都市冰雹主要集中在春夏之交的5月和受副高阻塞型系统影响的8月,发生时间集中在13:00—20:00。每年的冰雹日数在2004年前呈增加,最多时为8次,之后呈下降特点。东部的龙门山带降雹次数最多,受沱江水系的影响主要分布在官仓、柏合和书房,而北部和西南部降雹次数较少;主要受白马河水系影响,分布隆丰、安德和西崃区域。

The statistical analysis of hails in recent 30 years is conducted by use of the hail records of Chengdu Meteorological Service from 1984 to 2012, and the temporal variation, spatial distribution, and topographic characteristics of the hails are studied. The results show that the time of hail occurrence mainly concentrated around 13：00 to 20：00; the hail occurred most frequently in May and August; the annual number of hail days increased with a maximum of 8 before in 2004 and declined afterwards. The areas with most hails were Guancang, Baihe, and Shufang of the eastern Chengdu, influenced by the Tuojiang River basin, while the areas with least hails were Longfeng, Ande, and Xilai of the north and southwest Chengdu, influenced by the Baima River.