淮河流域上游分区气象-水文干旱传播特征及响应概率研究

Study on Propagation Characteristics and Response Probabilities of Meteorological and Hydrological Drought Zones in the Upper Reaches of Huai River

[目的]探究气象—水文干旱传播特征及响应概率,为水文干旱预警提供科学参考。[方法]基于淮河上游35个气象站及王家坝、息县水文站1980—2013年气象、水文数据,将王家坝以上流域分为息县(XX)和息县—王家坝区间(WJB)两个子流域,分别计算各分区的标准化蒸散发指数(SPEI)和标准化径流指数(SRI),利用相关系数法计算各分区的气象—水文干旱响应时间,据此对气象、水文干旱事件进行匹配,从而得出不同分区的气象—水文干旱传播特征,进一步结合Copula联合分布函数与贝叶斯网络构建淮河上游分区气象—水文干旱响应概率模型,计算不同重现期下的气象—水文干旱响应概率。[结果](1)WJB与XX气象—水文干旱响应时间分别为7个月与5个月,两个分区平均干旱传播历时约为1个月,平均干旱解除历时约为2个月;(2)WJB与XX气象干旱历时、强度总体上小于相应的水文干旱特征值,且WJB水文干旱对气象干旱敏感度低于XX;(3)WJB与XX气象—水文干旱响应概率与气象干旱历时、强度、烈度成正比,WJB更易发生干旱历时较长的水文干旱事件,而XX更易发生干旱强度、烈度较大的水文干旱事件;(4)气象干旱传播为相同重现期水文干旱的气象—水文干旱响应概率呈现随重现期增大而减小的特征,且XX气象—水文干旱响应概率大于WJB。[结论]XX与WJB两个分区的气象—水文干旱传播特征以及响应概率均存在差异,应针对性地加强水文干旱预警研究。

[Objective]Exploring the propagation characteristics and response probability of meteorological hydrological drought is conducive to providing scientific reference for hydrological drought early warning.[Methods]Based on the meteorological and hydrological data of 35 meteorological stations and Wangjiaba and Xixian hydrologic stations in the upper reaches of the Huai River from 1980 to 2013,the basin above Wangjiaba was divided into two sub basins:Xixian(XX)and Xixian Wangjiaba interval(WJB).The Standardized Precipitation Evapotranspiration Index(SPEI)and Standardized Runoff Index(SRI)of each region were calculated respectively,and the meteorological hydrological drought response time of each region was calculated by using the correlation coefficient method.The hydrological drought events were matched to obtain the meteorological hydrological drought propagation characteristics of different regions.Further,combined with Copula joint distribution function and Bayesian network,the meteorological hydrological drought response probability model of the upper reaches of the Huai River was constructed to calculate the meteorological hydrological drought response probability under different return periods.[Results](1)The response time of meteorological hydrological drought in WJB and XX was 7 months and 5 months,respectively,the average drought propagation duration in the two regions was about 1 month,and the average drought relief duration was about 2 months.(2)The durations and intensities of meteorological drought in WJB and XX were generally less than the corresponding hydrological drought characteristic values,and the sensitivity of hydrological drought in WJB to meteorological drought was lower than XX.(3)The meteorological hydrological drought response probabilities of WJB and XX were in direct proportion to the duration,intensity and intensity of meteorological drought.WJB was more prone to hydrological drought events with longer drought duration,while XX was more prone to hydrological drought events with greater drought intensity and intensity.(4)When meteorological drought spreaded to hydrological drought with the same return period,the response probability of meteorological hydrological drought decreased with the increase of return period,and the response probability of XX meteorological hydrological drought was greater than WJB.[Conclusion]There were differences in the meteorological and hydrological drought propagation characteristics and response probability between XX and WJB.Therefore,the hydrological drought early warning research should be strengthened based on the differences.