摘要
利用丽水地区2004—2014年的加密气象观测站的逐小时降水观测资料,统计分析了丽水地区短时强降水的时空分布特征,同时结合当地地理环境特征,对时空分布特征的成因进行了分析。结果表明:空间上,丽水地区短时强降水主要存在两个活跃区,分别位于东南部地区与西南部高山地区,地形陡峭区、喇叭口等特殊地形有助于短时强降水的发生;小时雨量最大的站点紧邻水库。时间上,从月分布特征来看,丽水地区短时强降水主要发生在5—9月,受汛期降水与热带天气系统影响,峰值分别出现在6月与8月;从日变化特征来看,丽水地区短时强降水主要呈现三峰分布特征,包括一个显著峰值与另外两个不显著峰值,其中主峰发生在午后14:00—22:00,次峰分别在03:00和08:00,不同季节日变化峰值略有不同。此外,小时雨量最大值出现在日落前后,地形导致的局地热力环流对短时强降水有增幅作用。
By using intensive hourly weather station precipitation data from 2004 to 2014, the temporal-spatial distribution characteristics of short-time heavy precipitation （STHP） in Lishui were analyzed. Combined with the local geographical characteristics, courses of the temporal-spatial distribution features were analyzed. Statistical results show that： from space aspect, there are two active areas of STHP in Lishui, and they are located in the southeast and southwest mountain region of Lishui respective- ly. Some special terrains such as steep and trumpet-shaped terrain are beneficial to the occurrence of STHP. In addition, the station with the strongest hourly heavy precipitation is adjacent to reservoir. From time aspect, according to the monthly variation characteristics, the STHP in Lishui is active during May--September. The most active STHP months, affected by flood period precipitation and tropical weather system, are June and August. According to the diurnal variation characteristics, the STHP shows one significant peak and two insignificant peaks, with the most active peak during 14：00- 22：00, the other two peaks during 03：00 and 08：00. The peak time of STHP varies a little in different seasons. Moreover, hourly rainfall intensity peaks appear before or after sunset, the local thermal circulation caused by topography may have enhancement effect on STHP.
出处
《气象与环境科学》
2016年第3期44-49,共6页
Meteorological and Environmental Sciences
基金
浙江省青年科技项目(2014QN21)资助
关键词
短时强降水
时空分布
日变化
short-time heavy precipitation
temporal-spatial distribution
diurnal variation
