摘要
分析楚雄州2014~2016年有记录的20起山洪灾害的灾情时间和空间分布特征及其与降水的关系。采用区域临界雨量法、泰森多边形法和算术平均法3种统计方法对分析区域临界雨量进行计算分析。结果表明,泰森多边形法因考虑了各雨量站的权重,结果相对较合理,精度较高,故采用泰森多边形法求得的临界面雨量值作为当地山洪气象风险预警阈值;对于没有灾情的山洪沟区域,使用全州总体的雨洪关系得到不同预报预警等级的临界雨量值,即非河谷地区山洪灾害气象预警Ⅳ级~Ⅰ级对应的临界雨量值为9.2mm、26.1mm、48.4mm、66.7mm,河谷地区山洪灾害气象预警Ⅳ级~Ⅰ级对应临界雨量值分别为7.8mm、13.5mm、17mm、25.5mm。经2017年灾情检验,修订后的临界面雨量阈值相比于当时业务系统中的原始阈值更有指示意义。
According to recorded 20 mountain torrents over Chuxiong from 2014 to 2016,the characteristics of temporal and spatial distribution of the 20 disasters,the relationship between precipitation and disasters are analyzed.The critical rainfall is calculated based on different algorithms including the regional critical rainfall method,the Thiessen Polygons and the Arithmetic mean method.The calculation of critical rainfall based on the Thiessen Polygons is more reasonable and more accurate for the reason that the Thiessen Polygons takes the weight of each rain station into consideration.Therefore,the critical rainfall based on the Thiessen Polygons is adopted as the threshold of the weather risk early warning for the mountain torrents over Chuxiong.The values of critical rainfall of different forecast warning levels for the mountain flood ditch without disaster are obtained by the general relationship between precipitation and mountain torrents over Chuxiong.For the valleys of Chuxiong,the values of critical rainfall for different forecast warning levels ranging from IV to I are 7.8 mm,13.5 mm,17 mm and 25.5 mm,respectively.For the non-river valley of Chuxiong,the values are 9.2 mm,26.1 mm,48.4 mm and 66.7 mm,respectively.The inspection of mountain torrents in 2017 reveals that the revised critical rainfall is more instructive than that used in the business system.
作者
刘博文
李华宏
胡娟
LIU Bo-wen;LI Hua-hong;HU Juan(Yunnan Meteorological Observatory,Kunming 650034,Yunnan,China)
出处
《云南地理环境研究》
2019年第2期6-12,共7页
Yunnan Geographic Environment Research
基金
国家自然科学基金项目“云南强降水过程背景下短时强降水天气特征分析及机理研究”(41565004)
国家自然科学基金项目“西行台风影响下云南强降水天气过程的机理研究”(41805037)
关键词
楚雄州
山洪
临界雨量
泰森多边形法
风险预警
Chuxiong prefecture
mountain torrents
critical rainfall
Thiessen Polygons
risk warning
