摘要
利用云南1981-2015年125个测站逐时降水观测资料,分析了云南短时强降水时空分布特征。结果表明:云南境内的短时强降水发生频率空间分布极不均匀,自东南向西北呈迅速递减趋势。南部和东部边缘的短时强降水特征最为突出,西北部特别是怒江北部区域尽管年降水量较大,但短时强降水特征并不明显。云南大部地区的短时强降水主要发生在5-10月份,其中7、8月份达到高发峰值。但不同区域之间存在一定的差异,滇东南、滇西南区域短时强降水出现的时间比较早(3月)、结束的时间也较晚(11月)。短时强降水还具有明显的日变化特征,傍晚至夜间为高发时段。其中,滇东北区域短时强降水在前半夜时段为高发期、滇西南区域在后半夜短时段为高发期。云南境内的短时强降水频次线性变化、年代际变化趋势不明显,但年际差异较大。呈现出1997年后为上升趋势,2006年后转为下降趋势,2013年至今为上升趋势的特点。
Based on the hourly precipitation data of 125 weather stations in Yunan Province from 1981 to 2015, the spatio-temporal characteristics of short-time heavy rainfall are investigated. The results indicate that the mean annual frequency of short-time heavy rainfall is not homogeneous distribution in Yunan, it shows a drop trend from southeast region to northwest region. As the centers of mean annual precipitation, there are obvious torrential rain characteristics in the east region and south verge, but it is distinctness in the north region of Nujiang. The short-time heavy rainfall commonly happens between May and October, further more there is a highest frequency in July and August. But it maybe happens early in March and disappears late in November in west and south region. On the other hand the frequency of short-time heavy rainfall shows a particular hourly change line, which always gets a peak at evenfall and night. There is an especial period that the short-time heavy rainfall continually occurs, it is from nightfall to midnight in the northeast region, and latter half of the night in the southwest region. The line- ar variation and interdecadal variation trend of short-time heavy rainfall frequency are not obvious in Yunan, but the interannual variation trend is noticeable, which shows a uptrend from 1997, turn to a downtrend at 2006, and then turn to a uptrend at 2013.
出处
《灾害学》
CSCD
2017年第3期57-62,共6页
Journal of Catastrophology
基金
国家自然科学基金项目(41565004)
云南省科技惠民专项(2016RA096)
关键词
短时强降水
空间分布
日内变化
云南
short-time heavy rainfall
spatial distribution
hourly change
Yunan Province
作者简介
李华宏（1978-），男，云南寻甸人，博士，主要从事中尺度数值模式应用、强降水预报预警技术研究．E-mail：lihuahong08@163．com
