黄河旱涝变化特征及应对过程

Characteristics of Drought and Wetness in the Yellow River and Its Countermeasures

为了科学识别黄河旱涝变化特征及应对能力,提出连续丰水年和连续枯水年的判定方法,采用标准化径流指数(SRI)和标准化旱涝急转指数(SDWAI)识别1956—2020年黄河利津站径流旱涝变化特征,分析水库调度在应对旱涝急转和连续枯水年中发挥的作用。结果显示:在月尺度,利津站SRI评估结果以正常至中旱为主,旱涝急转事件较少,且集中于汛期与非汛期的过渡时段;在年尺度,超过60%的年份被评估为正常或轻旱,且SRI对旱涝的评估结果与采用距平值的丰枯评估结果的一致性较好;在多年尺度,利津站发生了3次连续丰水年和2次连续枯水年,连续枯水年持续时间较长。随着水库调蓄能力的增强,已经能够较好地应对黄河旱涝急转事件,但对连续枯水年的应对能力不足。

In order to scientifically identify the characteristics of drought and wetness in the Yellow River and the coping capacity,this paper put forward a judgment method of continuous wet years and continuous dry years,used the Standardized Runoff Index(SRI)and the Stand-ardized Drought-Wetness Abrupt Alteration Index(SDWAI)to identify the characteristics of runoff changes at Lijin Station of the Yellow Riv-er from 1956 to 2020,and analyzed the role of reservoir operation in coping with the drought-wetness abrupt alteration events and continuous dry years.The results show that on a monthly scale,the SRI assessment results of Lijin Station are mainly normal to moderate drought,with only a few drought-wetness abrupt alteration events which mainly happen during the transition period between flood season and non-flood sea-son.On an annual scale,more than 60%of the years are assessed as normal or light drought,and the SRI assessment results are consistent with the assessment results using anomaly value.On a multi-year scale,there are 3 continuous wet years and 2 continuous dry years at Lijin Station,and the continuous dry years last for a long time.With the enhancement of reservoir regulation and storage capacity,drought-wetness abrupt alteration events are handled well,but the capacity to cope with continuous dry years is insufficient.