水库抗暴雨能力概率预报的降雨情景构建方法EI北大核心CSCD

针对中小型水库抗暴雨能力预报中存在不确定性的问题,提出了一种考虑降水总量与降雨历时联合概率分布的降雨情景构建方法,旨在减轻抗暴雨能力计算中降雨历时及雨型不同对预报结果产生的影响,以实现中小型水库抗暴雨能力的概率预报。该方法基于Copula函数构建降水总量和降雨历时的联合分布,并与各历时下代表雨型结合,生成同一降水总量下不同历时的降雨过程及其概率;以概率降雨情景为输入,计算水库抗暴雨能力,最终得到水库抗暴雨能力的阈值区间及概率分布。实例验证结果表明,该方法考虑了不同历时降雨发生概率对入库径流的影响,可为中小水库抗暴雨能力的概率预报提供切实可行的降雨情景构建方法。

A method of constructing rainfall scenario for probability forecast of rainstorm resistance capacity of reservoirs

For the uncertainty in the forecast of rainstorm resistance capacity of small- and medium-sized reservoirs, a method of constructing rainfall scenarios considering the joint probability distribution of rainfall amount and duration was proposed, alleviating the impact of the difference in rainfall duration or rain type on the forecast result and realizing the probability forecast of rainstorm resistance capacity of small- and medium-sized reservoirs. A joint probability distribution of rainfall amount and duration was built based on the Copula function and combined with the corresponding rain type at each duration to generate rainfall processes and probabilities at the same rainfall amount. Taking the probabilistic rainfall scenario as the input, the rainstorm resistance capacity of reservoirs was calculated, and the threshold interval and probability distribution were obtained. The results of a case study show that the method considers the impacts of probabilities of different rainfall durations on inflow of reservoirs, and provides a feasible rainfall scenario construction method for the probability forecast of rainstorm resistance capacity of small- and medium-sized reservoirs.