In order to mitigate the flooding disasters induced by severe rainfall over mountain regions,it is very important to estimate the water collection amount. However,in arid mountain regions,meteorological and hydrological stations are usually scarce and unevenly distributed,leading to difficulties in the estimation of this parameter. In such cases,a reasonable estimation of the areal rainfall is necessary and offers the initial conditions for driving hydrological models. In this paper,we studied an extreme rainfall event that occurred in Hami City,Xinjiang,China on July 31,2018 and that resulted in the break of a local dam. The northeastern part of Hami corresponds to the easternmost area of the Tianshan Mountains. This area is characterized by very hot summers and an annual mean precipitation of 43–118 mm. Due to a lack of vegetation,flooding disasters occur frequently along the hilly southern slope of this area;nevertheless,local meteorological and hydrological stations are rare. On July 31,2018,from midnight to 13：00,an extreme rainfall event occurred over northeastern Hami and led to a severe flood. This caused the break of the Sheyuegou Reservoir and,consequently,the death of many people. In this paper,the areal rainfall,water collection amount,and breaking process of the local dam were objectively evaluated. In order to obtain a reasonable estimation of the areal rainfall,three interpolation methods were applied to the meteorological station data,together with a multi-source fusion data reanalysis. Overall,the four estimation methods demonstrated correlations between 0.76–0.97;notably,the best estimation was given by the multi-source fusion data reanalysis. The estimated areal rainfall was then used to drive the FloodArea Model,obtaining the water collection amount for the upper reach of the Sheyuegou Reservoir：the values varied between 1.471×107 m3 and 2.892×107 m3. The water collection amount obtained by using the CMPAS areal rainfall was further compared with the results of a post-disaster investigation on the dam breaking process. The calculated hourly water collection amount and the flood peak flow were in good agreement with the results of the post-disaster investigation. In particular,the flood peak flow was 1.756 × 103 m3·s-1 （very similar to that derived from hydrological observations）,while the total flood charge was 2.639×107 m3 （much higher that the flood control and spillway carrying capacities of the reservoir）.
[1] 周顺武,王传辉,吴萍,等. 青藏高原强降水日数的时空分布特征[J]. 干旱区地理,2012,35(1):23–31.
[ZHOU Shunwu,WANG Chuanhui,WU Ping,et al.Temporal and spatial distribution of strong precipitation days over the Tibetan Plateau[J].Arid Land Geography,2012,35(1):23–31.]
[2] 曹永强,张亮亮,王学凤,等. 辽宁省夏季降水量和极端雨量日时空变化特征分析[J]. 干旱区地理,2017,40(2):266–275.
[CAO Yongqiang,ZHANG Lianglaing,WANG Xuefeng,et al.Characteristics of spatio-temporal variation of summer precipitation and extreme rainfall days in Liaoning Province in recent 54 years[J]. Arid Land Geography,2017,40(2):266–275.]
[3] WU Shiangjen,HSU Chintsung,LIEN Hocheng,et al.Modeling the effect of uncertainties in rainfall characteristics on flash flood warning based on rainfall thresholds[J]. Natural Hazards, 2015,75(2):1677–1711.
[4] 谢泽明,周玉淑,杨莲梅. 新疆降水研究进展综述[J]. 暴雨灾害,2018,37(3):204–212.
[XIE Zeming,ZHOU Yushu,YANG Lianmei.Review of study on precipitation in Xinjiang[J]. Torrential Rain and Disasters,2018,37(3):204–212.]
[5] 周惠成,宋天宇,吴剑. 山丘区小流域暴雨洪水预报预警问题分析及建议[J]. 中国防汛抗旱,2016,26(5):52–53.
[ZHOU Huicheng,SONG Tianyu,WU Jian.Analysis and suggestions of the rainstorm and flood warning and forecasting of small watershed in hill district[J]. China Flood and Drought Management,2016,26(5):52–53.]
[6] NORBIATO,DANIELE,BORGA. Flash flood warning based on rainfall thresholds and soil moisture conditions:An assessment for gauged and ungauged basins[J]. Journal of Hydrology,2008,362(3):274–290.
[7] 郭良,丁留谦,孙东亚,等. 中国山洪灾害防御关键技术[J]. 水利学报,2018,49(9):101–114.
[GUO Liang,DING Liuqian,SUN Dongya,et al.Key techniques of flash flood disaster prevention in China[J]. Journal of Hydraulic Engineering,2018,49(9):101–114.]
[8] 张红萍. 山区小流域洪水风险评估与预警技术研究[D]. 北京:中国水利水电科学研究院,2013.
[ZHANG Hongping.Study on the flood risk management and technology of the small mountain watershed[D]. Beijing:China Institute of Water Resources and Hydropower Research,2013.]
[9] MICHAUD J,SOROOSHIAN S.Comparison of simple versus complex distributed runoff models on a midsized semiarid watershed[J]. Water Resources Re-search,1994,30(3):593–605.
[10] 张雪松,郝芳华,张建永. 降雨空间分布不均匀性对流域径流和泥沙模拟影响研究[J]. 水土保持研究,2004,11(1):9–12.
[ZHANG Xuesong,HAO Fanghua,ZHANG Jianyong.Study on effect of uncertainty in spatial distribution of rainfall on runoff and sediment modeling[J]. Research of Soil and Water Conservation,2004,11(1):9–12. ]
[11] 章国材. 暴雨洪涝预报与风险评估[M]. 北京:气象出版社,2012:119–125.
[ZHANG Guocai.Forecast and risk assessment of rainstorm flood[M]. Beijing:China Meteorological Press,2012:119–125.]
[12] 肖安,许爱华. 2016年华南地区一次大暴雨过程的空报原因分析[J]. 暴雨灾害,2018,37(2):124–134.
[XIAO An,XU Aihua.Cause analysis on false prediction of an extreme heavy rain event in southern China in 2016[J]. Torrential Rain and Disasters,2018,37(2):124–134.]
[13] 韩平,程先富. 洪水灾害损失评估研究综述[J]. 环境科学与管理,2012,37(4):61–64.
[HAN Ping,CHENG Xianfu.Review on flood loss evaluation[J]. Environmental Science and Management,2012,37(4):61–64.]
[14] 赵战成. 库尔勒一次强对流大暴雨天气特征分析[J]. 干旱区地理,2016,39(5):1070–1077.
[ZHAO Zhancheng.Characteristics of a strong convective weather and heavy rainstorm in Korla City,Xinjiang[J]. Arid Land Geography,2016,39(5):1070–1077.]
[15] 张连成,江远安,刘精,等. 基于FloodArea模型新疆山洪淹没模拟及致灾临界雨量阈值的研究——以皮里青河流域为例[J]. 干旱区地理,2018,41(1):48–55.
[ZHANG Liancheng,JIANG Yuan’an,LIU Jing,et al.Mountain flood simulation and critical rainfall threshold incurring disaster based on the Floodarea model: A case of Piliqing River Valley as an example[J]. Arid Land Geography,2018,41(1):48–55.]
[16] 潘旸,沈艳,宇婧婧,等. 基于贝叶斯融合方法的高分辨率地面—卫星—雷达三源降水融合试验[J]. 气象学报,2015,73(1):177–186.
[PAN Yang,SHEN Yan,YU Jingjing,et al.An experiment of high-resolution gauge-radar-satellite combined precipitation retrieval based on the Bayesian merging method[J]. Acta Meteorological Sinica,2015,73(1):177–186.]
[17] 宇婧婧,沈艳,潘旸,等. 中国区域逐日融合降水数据集与国际降水产品的对比评估[J]. 气象学报,2015,73(2):394–410.
[YU Jingjing,SHEN Yan,PAN Yang,et al.Comparative assessment between the daily merged precipitation dataset over China and the world’s popular counterparts[J]. Acta Meteorologica Sinica,2015,73(2):394–410.]
[18] GEOMER. Floodarea:Arc view extension for calculating flooded area (User manual Version 2.4)[M]. Heidelberg:Geomer Gmph,2003.
[19] 张明达,李蒙,戴丛蕊,等. 基于FloodArea模型的云南山洪淹没模拟研究[J]. 灾害学,2016,31(1):78–82.
[ZHANG Mingda,LI Meng,DAI Congrui,et al.Simulation Study of Flood in Yunnan based on the FloodArea Model[J]. Journal of Catastrophology,2016,31(1):78–82.]
[20] 张容焱,游立军,高建芸,等. 统计方法与淹没模型结合的山洪灾害风险评估方法及其应用[J]. 气象,2013,39(12):1642–1648.
[ZHANG Rongyan,YOU Lijun,GAO Jianyun,et al.Flash floods disaster risk assessment method combination of statistical and inundated model and its application[J]. Meteorological Monthly,2013,39(12):1642–1648.]
[21] 罗尊骅,林广发,张容焱,等. FloodArea模型糙率系数改进方法[J]. 海南师范大学学报(自然科学版),2018,31(1):98–104.
[LUO Zunhua,LIN Guangfa,ZHANG Rongyan,et al.An improved method of calculating roughness coefficient for Floodarea[J]. Journal of Hainan Normal University (Natural Science),2018,31(1):98–104.]
[22] 许多涛,李晓. 四川都江堰市白依庵泥岩矿区水文地质条件及最大汇水量评估[J]. 水土保持研究,2006,13(3):184–186.
[XU Duotao,LI Xiao.Assessment of hydrogeological conditions and the largest water-collecting amount in Baiyian Mudstone Mining Area,Du jiangyan,Sichuan[J]. Research of Soil and Water Conservation,2006,13(3):184–186.]
