淮河中上游流域极端气候变化特征及其对干旱的影响

Change Characteristics of Extreme Climate Elements and Its Impact on Drought in the Upper and Middle Reaches of Huai River Basin

为揭示淮河中上游流域极端气候变化及其对干旱的影响,基于淮河中上游流域19个气象站点1960—2015年观测资料,由RClimDex计算出27个极端气候指数,通过线性拟合、Mann-Kendall趋势检验和反距离权重插值等方法分析淮河中上游极端气候指数的动态变化,并与标准化降水蒸散指数进行相关性分析。研究发现:(1)时间特征上,流域极端气温相对指数和绝对指数表现为波动的下降趋势,极值指数和其他指数呈现上升趋势;过去56年中除持续干燥指数(CWD)呈减少趋势外,其他降水指数均呈增加趋势。(2)空间特征上,极端气温指数的上升或下降趋势在全流域基本保持一致,而极端降水指数区域差异性明显。(3)流域极端气温指数主要受纬度的影响,其次是海拔,受经度影响最小。(4)从SPEI和极端气候指数相关性分析中发现极端降水指数对SPEI影响更大。研究结果可为区域水资源安全、优化配置以及防灾减灾等提供参考依据。

In order to reveal the extreme climate change and its impact on drought in the upper and middle reaches of Huai River Basin(UMHRB),the research calculated 27 extreme climate indexes by using RClimDex based on the observation data of 19 meteorological stations in the UMHRB from 1960 to 2015,and then used linear fitting,Mann-Kendall test and inverse distance weight interpolation to analyze the dy⁃namic changes of extreme climate indexes.In addition,the correlation analysis between extreme climate elements and the standardized precip⁃itation evapotranspiration index(SPEI)were also carried out.The results show that:(1)In terms of time characteristics,the relative indexes and absolute indexes of extreme temperature show decreasing trend,while the extreme indexes and other indexes show increasing trend;In the past 56 years,except the continuous drying index(CWD),all the other precipitation indexes show increasing trend.(2)In terms of spatial characteristics,the rising or falling trend of extreme temperature index is basically the same in the whole basin,while the regional difference of extreme precipitation index is obvious.(3)The extreme temperature index is mainly affected by latitude,followed by altitude,and is least af⁃fected by longitude.(4)From the correlation analysis between SPEI and extreme climate index,it is found that extreme precipitation index has a greater impact on SPEI.The results could provide references for regional water resources security,optimal allocation and disaster prevention and reduction.