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A two-step approach to investigate the effect of rating curve uncertainty in the Elbe decision support system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1229-1238页

作者： yue-ping xu Harriette HOLZHAUER Martijn J. BOOIJ Hong-yue SUN Institute of Hydrology and Water Resources Department of Civil Engineering Zhejiang University Hangzhou 310027 China Water Engineering and Management Faculty of Engineering Technology University of Twente 7500 AE Ensehede the Netherlands Institute of Harbor Coast and Offshore Engineering Department of Civil Engineering Zhejiang University Hangzhou 310027 China

For river basin management, the reliability of the rating curves mainly depends on the accuracy and time period of the observed discharge and water level data. In the Elbe decision support system (DSS), the rating curves are combined with the HEC-6 model to investigate the effects of river engineering measures on the Elbe River system. In such situations, the uncertainty originating from the HEC-6 model is of significant importance for the reliability of the rating curves and the corresponding DSS results. This paper proposes a two-step approach to analyze the uncertainty in the rating curves and propagate it into the Elbe DSS: analytic method and Latin Hypercube simulation. Via this approach the uncertainty and sensitivity of model outputs to input parameters are successfully investigated. The results show that the proposed approach is very efficient in investigating the effect of uncertainty and can play an important role in improving decision-making under uncertainty.

关键词： Elbe decision support system (DSS) Two-step approach Uncertainty HEC-6 model

Canonical correlation analysis of hydrological response and soil erosion under moving rainfall

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第5期14卷 353-361页

作者： Qi-hua RAN Zhi-nan SHI yue-ping xu Institute of Hydrology and Water Resources Zhejiang University

The impacts of rainfall direction on the degree of hydrological response to rainfall properties were investigated using comparative rainfall-runoff experiments on a small-scale slope(4 m×1 m),as well as canonical correlation analysis(CCA).The results of the CCA,based on the observed data showed that,under conditions of both upstream and downstream rainfall movements,the hydrological process can be divided into instantaneous and cumulative responses,for which the driving forces are rainfall intensity and total rainfall,and coupling with splash erosion and wash erosion,*** response of peak runoff(Pr)to intensity-dominated rainfall action appeared to be the most significant,and also runoff(R)to rainfall-dominated action,both for upstream-and downstream-moving ***,the responses of sediment erosion in downstream-moving condition were more significant than those in upstream-moving *** study indicated that a CCA between rainfall and hydrological characteristics is effective for further exploring the rainfall-runoff-erosion mechanism under conditions of moving rainfall,especially for the downstream movement condition.

关键词： Moving rainfall Runoff Sediment erosion Canonical correlation analysis(CCA)

Evaluation of TIGGE Daily Accumulated Precipitation Forecasts over the Qu River Basin, China

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Journal of Meteorological Research 2019年第4期33卷 747-764页

作者： Li LIU Chao GAO Qian ZHU yue-ping xu Institute of Hydrology and Water Resources College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058 School of Civil Engineering Southeast UniversityNanjing 210096

Quantitative precipitation forecasts(QPFs)provided by three operational global ensemble prediction systems(EPSs)from the THORPEX(The Observing System Research and Predictability Experiment)Interactive Grand Global Ensemble(TIGGE)archive were evaluated over the Qu River basin,China during the plum rain and typhoon seasons of 2009–*** post-processing methods,the ensemble model output statistics based on censored shifted gamma distribution(CSGD-EMOS)and quantile mapping(QM),were used to reduce bias and to improve the *** results were evaluated by using three incremental precipitation thresholds and multiple verification *** is demonstrated that QPFs from NCEP and ECMWF presented similarly skillful forecasts,although the ECMWF QPFs performed more satisfactorily in the typhoon season and the NCEP QPFs were better in the plum rain *** of the verification metrics showed evident seasonal discriminations,with more satisfactory behavior in the plum rain *** precipitation tended to be overestimated,but heavier precipitation was always *** post-processed QPFs showed a significant improvement from the raw forecasts and the effects of post-processing varied with the lead time,precipitation threshold,and *** was better corrected at longer lead times and higher ***-EMOS was more effective for probabilistic metrics and the root-mean-square *** had a greater effect on removing bias according to bias and categorical metrics,but was unable to warrant *** general,raw forecasts can provide acceptable QPFs eight days in *** post-processing,the useful forecasts can be significantly extended beyond 10 days,showing promising prospects for flood forecasting.

关键词： TIGGE quantitative precipitation forecasts quantile mapping censored shifted gamma distribution

Estimation of future water resources of Xiangjiang River Basin with VIC model under multiple climate scenarios

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Water Science and Engineering 2017年第2期10卷 87-96页

作者： Guo-qing Wang Jian-yun Zhang yue-ping xu Zhen-xin Bao Xin-yue Yang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Research Center for Climate Change Ministry of Water Resources Institute of Hydrology and Water Resources Civil EngineeringZhejiang University College of Hydrology and Water Resources Hohai University

Variation trends of water resources in the Xiangjiang River Basin over the coming decades have been investigated using the variable infiltration capacity(VIC) model and 14 general circulation models'(GCMs') projections under the representative concentration pathway(RCP4.5) scenario. Results show that the Xiangjiang River Basin will probably experience temperature rises during the period from 2021 to2050, with precipitation decrease in the 2020 s and increase in the 2030 s. The VIC model performs well for monthly discharge simulations with better performance for hydrometric stations on the main stream of the Xiangjiang River than for tributary catchments. The simulated annual discharges are significantly correlated to the recorded annual discharges for all the eight selected target stations. The Xiangjiang River Basin may experience water shortages induced by climate change. Annual water resources of the Xiangjiang River Basin over the period from 2021 to 2050 are projected to decrease by 2.76% on average within the range from-7.81% to 7.40%. It is essential to consider the potential impact of climate change on water resources in future planning for sustainable utilization of water resources.

关键词： Water resources Climate change VIC model Xiangjiang River Basin Climate scenarios Hydrological modeling

Drought analysis using multi-scale standardized precipitation index in the Han River Basin,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第6期12卷 483-494页

作者： yue-ping xu Sheng-ji LIN Yan HUANG Qin-qing ZHANG Qi-hua RAN Institute of Hydrology and Water Resources Civil Engineering Zhejiang University Hangzhou 310058 China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020 China Bureau of Hydrology Changjiang Water Resources Commission Wuhan 430010 China

Regional drought analysis provides useful information for sustainable water resources *** this paper,a standardized precipitation index(SPI) at multiple time scales was used to investigate the spatial patterns and trends of drought in the Han River Basin,one of the largest tributaries of Yangtze River,*** was found that,in terms of drought severity,the upper basin of the Han River is the least,while the growing trend is the most conspicuous;a less conspicuous growing trend can be observed in the middle basin;and there is an insignificant decreasing trend in the lower ***,the impact of drought on the Middle Route of the South-to-North Water Transfer Project was investigated,and it is suggested that water intake must be reduced in times of drought,particularly when successive or simultaneous droughts in the upper and middle basins of the Han River Basin *** results can provide substantial information for future water allocation schemes of the South-to-North Water Transfer Project.

关键词： Multi-scale standardized precipitation index(SPI) South-to-North Water Transfer Project Spatial patterns Mann-Kendal Han River Basin

Impact of rainfall movement on soil crust development

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International Journal of Sediment Research 2012年第4期27卷 439-450页

作者： Qi-hua RAN Zhi-nan SHI xu-dong FU Guang-qian WANG yue-ping xu Institute of Hydrology and Water Resources Zhejiang University State Key Laboratory Of Hydroscience and Engineering Tsinghua University

The impact of rainfall event movement on soil crust development was investigated via laboratory experiments and physics-based hydrological-response *** and soil water content data were analyzed in order to study different crustal development periods under a variety of precipitation *** results showed that the formation of crust significantly changed soil saturated hydraulic conductivity（K;） and runoff,while a steady state,which could be broken by an extended period of raindrop impact,was found to exist for both the crust and,subsequently,runoff *** decrease in K;was as high as 86%for downstream-moving events,and 72%for upstream-moving events,illustrating that the direction of rainfall movement has a more significant impact on crust formation than rainfall intensity and *** downstream-moving rainfall events may have a greater effect than those moving upstream,the development of a depositional crust before raindrop impact may play an important role in determining the final K;value.

关键词： Moving rainfall Crust development Steady-state Saturated hydraulic conductivity

Qualitative and quantitative uncertainties in regional rainfall frequency analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第3期16卷 194-203页

作者： Qian ZHU Xiao xu Chao GAO Qi-hua yue-ping xu Institute of Hydrology and Water Resources Zhejiang University Hangzhou 310058 China

Uncertainty exists widely in hydrological analysis, and this makes the process of uncertainty assessment very im- portant for making robust decisions. In this study, uncertainty sources in regional rainfall frequency analysis are identified for the first time. The numeral unite spread assessment pedigree （NUSAP） method is introduced and is first employed to quantify qual- itative uncertainty in regional rainfall frequency analysis. A pedigree matrix is particularly designed for regional rainfall frequency analysis, by which the qualitative uncertainty can be quantified. Finally, the qualitative and quantitative uncertainties are com- bined in an uncertainty diagnostic diagram, which makes the uncertainty evaluation results more intuitive. From the integrated diagnostic diagram, it can be determined that the uncertainty caused by the precipitation data is the smallest, and the uncertainty from different grouping methods is the largest. For the downstream sub-region, a generalized extreme value （GEV） distribution is better than a generalized logistic （GLO） distribution; for the south sub-region, a Pearson type III （PE3） distribution is the better choice; and for the north sub-region, GEV is more appropriate.

关键词： Qualitative uncertainty Uncertainty analysis Numeral unite spread assessment pedigree (NUSAP) method Regional rainfall frequency analysis Pedigree matrix Diagnostic diagram

震后滑坡对陡峭山区小流域水文响应过程的影响——以汶川地震影响区小流域为例(英文)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第2期16卷 131-142页

作者： Qi-hua RAN Qun QIAN Wei LI xu-dong FU Xiao YU yue-ping xu Institute of Hydrology and Water Resources Zhejiang University State Key Laboratory of Hydroscience and Engineering Tsinghua University China Three Gorges Corporation

目的:明确汶川地震所引发的滑坡对震区小流域水文响应过程的影响,推进震区洪水过程的准确预报。创新:评估汶川地震对碱坪沟流域的下垫面条件的破坏,并在此基础上利用先进的分布式水文模型定量评估地震事件对小流域产汇流过程的影响。方... 详细信息

目的:明确汶川地震所引发的滑坡对震区小流域水文响应过程的影响,推进震区洪水过程的准确预报。创新:评估汶川地震对碱坪沟流域的下垫面条件的破坏,并在此基础上利用先进的分布式水文模型定量评估地震事件对小流域产汇流过程的影响。方法:1.选取四川省龙溪河地区的碱坪沟小流域作为研究区域,利用遥感影像数据以及数字高程数据获得滑坡区的分布以及高程变化情况;2.运用基于物理概念的综合水文模型(In HM)对该流域水文过程进行模拟精度验证;3.对滑坡发生前后的降雨产流过程分别进行数值模拟,探讨在同样降雨条件下,由于滑坡所引起的下垫面特性变化对产流过程的影响。结论:1.震后滑坡灾害所带来的下垫面变化导致了流域内的山洪特性变化,且在流域内局部地区的表现更为明显,局部山洪危害增加;2.与震前相比,随着暴雨规模的增强,震后下垫面变化所致的流量峰值增量也随之增加,峰值的增加比例在6小时雨量达到235 mm时急剧增大,但降雨持续增强后趋近于稳定值(约87%)。

关键词：水文响应数值模拟下垫面条件地震滑坡

Evaluation of a multi-site weather generator in simulating precipitation in the Qiantang River Basin, East China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第3期15卷 219-230页

作者： yue-ping xu Chong MA Su-li PAN Qian ZHU Qi-hua RAN Institute of Hydrology and Water Resources Civil Engineering Zhejiang University Hangzhou 310058 China

Recent years have seen a surge in assessment of potential impacts of climate change. As one of the most important tools for generating synthetic hydrological model inputs, weather generators have played an important role in climate change impact analysis of water management. However, most weather generators like statistical downscaling model （SDSM） and long Ashton research station weather generator （LARS-WG） are designed for single site data generation. Considering the significance of spatial correlations of hydro-meteorological data, multi-site weather data generation becomes a necessity. In this study we aim to evaluate the performance of a new multi-site stochastic model, geo-spatial temporal weather generator （GIST）, in simulating precipitation in the Qiantang River Basin, East China. The correlation matrix, precipitation amount and occurrence of observed and GiST-generated data are first compared for the evaluation process. Then we use the GiST model combined with the change factor method （CFM） to investigate future changes of precipitation （2071 2100） in the study area using one global climate model, Hadgem2 ES, and an extreme emission scenario RCP 8.5, The final results show that the simulated precipitation amount and occurrence by GiST matched their historical counterparts reasonably. The correlation coefficients between simulated and his- torical precipitations show good consistence as well. Compared with the baseline period （1961 1990）, precipitation in the future time period （2071-2100） at high elevation stations will probably increase while at other stations decreases will occur. This study implies potential application of the GiST stochastic model in investigating the impact of climate change on hydrology and water resources.

关键词： Climate change Change factor method (CFM) Multi-site weather generator Qiantang River Basin