Comparative Analysis of a Rare Autumn Rainstorm and a Spring Rainstorm in Xiamen Area

• 作者: Chen Yiliang Jiang Hangdong Luo Zhonghong Shen Huaping
• 来源期刊: 气象与环境研究：英文版
• 学科: 地球科学
• 关键词: 秋季暴雨 厦门地区 最大风速 多普勒天气雷达 顺时针旋转 高海拔地区 西部地区 暴雨过程
• 年，卷（期）: 2014,（2）
• 页码范围: 9-13
• 页数: 5页
• 分类号: P456.1

摘要

According to Ouyang potential temperature V-3θ charts,a rare autumn rainstorm in Xiamen on November 18,2011 was compared with a spring rainstorm on March 29,2005 firstly,and then the main characteristics of the autumn rainstorm were analyzed based on wind profiler data of Doppler weather radar. The results showed that ultra-low temperature on the top of the troposphere was more obvious in autumn than that in spring;clockwise tumble effect was distinct and warm and wet layer reached 300 hPa in both spring and autumn. Clockwise tumble effect appeared in various forms in autumn and spring. That is,the wind blew from the east at low altitudes and the west at high altitudes before the autumn rainstorm occurred; when the maximum wind speed appeared at 500 hPa,heavy rainfall occurred. During the spring rainstorm process,wind direction was consistent at each level and wind speed increased with the rise of altitude during early days. Afterwards,the wind blew from the east at low altitudes and the west at high altitudes. During the autumn rainstorm process,the heavy rainfall at the first stage was closely related to thickness of the 20m /s wind speed layer at 3-5 km. If the thickness declined sharply when the 20 m /s wind speed layer expended downwards,heavy rainfall would occur soon afterwards. Moreover,the precipitation intensity weakened immediately as the 20 m /s wind speed layer began to be stable. The heavy rainfall at the second stage was closely related to thickness of the 24 m /s wind speed layer,and the appearance,development and weakening of the 24 m /s wind speed layer foreboded the occurrence of heavy rainfall. Moreover,the thickness of the 24 m /s wind speed layer decreased to the minimum,and then heavy rainfall would appear soon afterwards. Hereafter,the thickness increased and then decreased again.