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1.
The January 2010 earthquake that devastated Haiti left its population ever more vulnerable to rainfall-induced flash floods. A flash flood guidance system has been implemented to provide real-time information on the potential of small (~70 km2) basins for flash flooding throughout Haiti. This system has components for satellite rainfall ingest and adjustment on the basis of rain gauge information, dynamic soil water deficit estimation, ingest of operational mesoscale model quantitative precipitation forecasts, and estimation of the times of channel flow at bankfull. The result of the system integration is the estimation of the flash flood guidance (FFG) for a given basin and for a given duration. FFG is the amount of rain of a given duration over a small basin that causes minor flooding in the outlet of the basin. Amounts predicted or nowcasted that are higher than the FFG indicate basins with potential for flash flooding. In preparation for Hurricane Tomas’ landfall in early November 2010, the FFG system was used to generate 36-h forecasts of flash flood occurrence based on rainfall forecasts of the nested high-resolution North American Model of the National Centers for Environmental Prediction. Assessment of the forecast flood maps and forecast precipitation indicates the utility and value of the forecasts in understanding the spatial distribution of the expected flooding for mitigation and disaster management. It also highlights the need for explicit uncertainty characterization of forecast risk products due to large uncertainties in quantitative precipitation forecasts on hydrologic basin scales.  相似文献   

2.
Adequacy of satellite derived rainfall data for stream flow modeling   总被引:2,自引:0,他引:2  
Floods are the most common and widespread climate-related hazard on Earth. Flood forecasting can reduce the death toll associated with floods. Satellites offer effective and economical means for calculating areal rainfall estimates in sparsely gauged regions. However, satellite-based rainfall estimates have had limited use in flood forecasting and hydrologic stream flow modeling because the rainfall estimates were considered to be unreliable. In this study we present the calibration and validation results from a spatially distributed hydrologic model driven by daily satellite-based estimates of rainfall for sub-basins of the Nile and Mekong Rivers. The results demonstrate the usefulness of remotely sensed precipitation data for hydrologic modeling when the hydrologic model is calibrated with such data. However, the remotely sensed rainfall estimates cannot be used confidently with hydrologic models that are calibrated with rain gauge measured rainfall, unless the model is recalibrated. G. Artan, J. L. Smith and K. Asante – work performed under USGS contract 03CRCN0001.  相似文献   

3.
张福义 《水文》1997,(6):13-19
综述了淮河流域概况,淮河干流洪水预报系统物采用的预报方法。1991年淮河干流洪水预报采用了降雨径流预报与上,下游站相应流量预防方法相配合,并注重实时水情分析;在行洪区多,行洪后水面宽广而比降又极小的河段的汇流计算,采用了以实测洪水资料绘制的经验蓄曲线为充分发挥的湖泊洪水演算方法。  相似文献   

4.
20世纪暴雨和洪水极值的年代际变化   总被引:1,自引:0,他引:1       下载免费PDF全文
利用20世纪100年(特别是后50年)2万多个雨量站和175个大中河流水文站的实测和调查雨量和流量资料,分析了中国大陆(外流区)暴雨和洪水极值的年代际变化,其中包括长期站暴雨的年代均值变化、20世纪50年点雨量极值的前后期平均值对比、最大点雨量发生年代分布和特大洪峰流量的年代分布。分别就5种历时、不同地区的暴雨洪水极值随年代的变化作了分析,揭示了变化的事实,计算了多项年代比率,探讨了影响因子。  相似文献   

5.
Flash flood forecasting of catchment systems is one of the challenges especially in the arid ungauged basins. This study is attempted to estimate the relationship between rainfall and runoff and also to provide flash flood hazard warnings for ungauged basins based on the hydrological characteristics using geographic information system (GIS). Morphometric characteristics of drainage basins provide a means for describing the hydrological behavior of a basin. The study examined the morphometric parameters of Wadi Rabigh with emphasis on its implication for hydrologic processes through the integration analysis between morphometric parameters and GIS techniques. Data for this study were obtained from ASTER data for digital elevation model (DEM) with 30-m resolution, topographic map (1:50,000), and geological maps (1,250,000) which were subject to field confirmation. About 36 morphometric parameters were measured and calculated, and interlinked to produce nine effective parameters for the evaluation of the flash flood hazard degree of the study area. Based on nine effective morphometric parameters that directly influence on the hydrologic behavior of the Wadi through time of concentration, the flash flood hazard of the Rabigh basin and its subbasins was identified and classified into three groups (High, medium, and low hazard degree). The present work proved that the physiographic features of drainage basin contribute to the possibility of a flash flood hazard evaluation for any particular drainage area. The study provides details on the flash flood prone subbasins and the mitigation measures. This study also helps to plan rainwater harvesting and watershed management in the flash flood alert zones. Based on two historical data events of rainfall and the corresponding maximum flow rate, morphometric parameters and Stormwater Management and Design Aid software (SMADA 6), it could be to generate the hydrograph of Wadi Rabigh basin. As a result of the model applied to Wadi Rabigh basin, a rainfall event of a total of 22 mm with a duration of 5 h at the station nearby the study area, which has an exceedance probability of 50 % and return period around 2 years, produces a discharge volume of 15.2?×?106 m3 at the delta, outlet of the basin, as 12.5 mm of the rainfall infiltrates (recharge).  相似文献   

6.
《Comptes Rendus Geoscience》2005,337(1-2):203-217
Advances in flood forecasting have been constrained by the difficulty of estimating rainfall continuously over space, for catchment-, national- and continental-scale areas. This has had a concomitant impact on the choice of appropriate model formulations for given flood-forecasting applications. Whilst weather radar used in combination with raingauges – and extended to utilise satellite remote-sensing and numerical weather prediction models – have offered the prospect of progress, there have been significant problems to be overcome. These problems have curtailed the development and adoption of more complete distributed model formulations that aim to increase forecast accuracy. Advanced systems for weather radar display and processing, and for flood forecast construction, are now available to ease the task of implementation. Applications requiring complex networks of models to make forecasts at many locations can be undertaken without new code development and be readily revised to take account of changing requirements. These systems make use of forecast-updating procedures that assimilate data from telemetry networks to improve flood forecast performance, at the same time coping with the possibility of data loss. Flood forecasting systems that integrate rainfall monitoring and forecasting with flood forecasting and warning are now operational in many areas. Present practice in flood modelling and forecast updating is outlined from a UK perspective. Challenges for improvement are identified, particularly against a background of greater access to spatial datasets on terrain, soils, geology, land-cover, and weather variables. Representing the effective runoff production and translation processes operating at a given grid or catchment scale may prove key to improved flood simulation, and robust application to ungauged basins through physics-based linkages with these spatial datasets. The need to embrace uncertainty in flood-warning decision-making is seen as a major challenge for the future. To cite this article: R.J. Moore et al., C. R. Geoscience 337 (2005).  相似文献   

7.
三峡工程大江截流水文泥沙监测规划   总被引:1,自引:0,他引:1  
戴水平  李云中 《水文》1999,(1):6-10
鉴于三峡工程大江截流是一项复杂的系统工程,具有水深大,流量大,抛投量大和截流期不断航等显著特点。水文泥沙监测作为其重要的组成部分,监测导流与截流过程中水流泥沙和水下地形的变化,为截流设计优化,调整施工方案与措施等提供科学的决策依据,同时也为导流明渠分流与通航,围堰度汛,截流水力学试验研究及水文预报,水文分析计算等提供水文原型观测资料。本文介绍了水文泥沙监测的目的、任务和水文数据采集,传输,处理与信  相似文献   

8.
The three most important components necessary for functioning of an operational flood warning system are: (1) a rainfall measuring system; (2) a soil moisture updating system; and, (3) a surface discharge measuring system. Although surface based networks for these systems can be largely inadequate in many parts of the world, this inadequacy particularly affects the tropics, which are most vulnerable to flooding hazards. Furthermore, the tropical regions comprise developing countries lacking the financial resources for such surface-based monitoring. The heritage of research conducted on evaluating the potential for measuring discharge from space has now morphed into an agenda for a mission dedicated to space-based surface discharge measurements. This mission juxtaposed with two other upcoming space-based missions: (1) for rainfall measurement (Global Precipitation Measurement, GPM), and (2) soil moisture measurement (Hydrosphere State, HYDROS), bears promise for designing a fully space-borne system for early warning of floods. Such a system, if operational, stands to offer tremendous socio-economic benefit to many flood-prone developing nations of the tropical world. However, there are two competing aspects that need careful assessment to justify the viability of such a system: (1) cost-effectiveness due to surface data scarcity; and (2) flood prediction uncertainty due to uncertainty in the remote sensing measurements. This paper presents the flood hazard mitigation opportunities offered by the assimilation of the three proposed space missions within the context of these two competing aspects. The discussion is cast from the perspective of current understanding of the prediction uncertainties associated with space-based flood prediction. A conceptual framework for a fully space-borne system for early-warning of floods is proposed. The need for retrospective validation of such a system on historical data comprising floods and its associated socio-economic impact is stressed. This proposal for a fully space-borne system, if pursued through wide interdisciplinary effort as recommended herein, promises to enhance the utility of the three space missions more than what their individual agenda can be expected to offer.  相似文献   

9.
Many researchers seek to take advantage of the recently available and virtually uninterrupted supply of satellite-based rainfall information as an alternative and supplement to the ground-based observations in order to implement a cost-effective flood prediction in many under-gauged regions around the world. Recently, NASA Applied Science Program has partnered with USAID and African-RCMRD to implement an operational water-hazard warning system, SERVIR-Africa. The ultimate goal of the project is to build up disaster management capacity in East Africa by providing local governmental officials and international aid organizations a practical decision-support tool in order to better assess emerging flood impacts and to quantify spatial extent of flood risk, as well as to respond to such flood emergencies more expediently. The objective of this article is to evaluate the applicability of integrating NASA’s standard satellite precipitation product with a flood prediction model for disaster management in Nzoia, sub-basin of Lake Victoria, Africa. This research first evaluated the TMPA real-time rainfall data against gauged rainfall data from the year 2002 through 2006. Then, the gridded Xinanjiang Model was calibrated to Nzoia basin for period of 1985–2006. Benchmark streamflow simulations were produced with the calibrated hydrological model using the rain gauge and observed streamflow data. Afterward, continuous discharge predictions forced by TMPA 3B42RT real-time data from 2002 through 2006 were simulated, and acceptable results were obtained in comparison with the benchmark performance according to the designated statistic indices such as bias ratio (20%) and NSCE (0.67). Moreover, it is identified that the flood prediction results were improved with systematically bias-corrected TMPA rainfall data with less bias (3.6%) and higher NSCE (0.71). Although the results justify to suggest to us that TMPA real-time data can be acceptably used to drive hydrological models for flood prediction purpose in Nzoia basin, continuous progress in space-borne rainfall estimation technology toward higher accuracy and higher spatial resolution is highly appreciated. Finally, it is also highly recommended that to increase flood forecasting lead time, more reliable and more accurate short- or medium-range quantitative precipitation forecasts is a must.  相似文献   

10.
汤成友  项祖伟  缪韧  舒栋才 《水文》2007,27(5):36-38,51
水箱模型用于实时洪水作业预报的具体成果尚不多,本文研究的目的在于将水箱模型用于大尺度流域实时洪水预报。本文介绍了应用水箱模型建立实时洪水预报模型的方法。按照河段流量传播时间将寸滩以上干、支流划分为若干子河段,各子河段按照计算时段长分成若干单元河段,各单元河段区间降雨径流预报采用水箱模型.河道流量演算采用连续马斯京根法。河系预报模型精度在85%以上,能够满足实时洪水预报的要求。  相似文献   

11.
七大流域水文特性分析   总被引:2,自引:0,他引:2  
刘伟  翟媛  杨丽英 《水文》2018,38(5):79-84
我国东西和南北方向地理跨度大,水文特性差异明显。从气候特征、降雨和径流、暴雨和洪水等方面,分析七大流域的水文特性,总结降雨和径流在上下游、干支流等空间上以及年内和年际等时间上的分布规律,并分析暴雨和洪水在成因、发生时间、空间分布、过程等方面的规律,为径流和洪水成果计算提供了基础,也为水文成果的合理性检验提供了参考。  相似文献   

12.
水文集合预报是一种既可以给出确定性预报值,又能提供预报值的不确定性信息的概率预报方法。简述了水文集合预报试验(Hydrologic Ensemble Prediction Experiment,HEPEX)国际计划的主要研究内容,回顾了HEPEX研究进展,分析了对水文预报发展有重要意义的3个HEPEX前沿研究:降尺度研究、集合预报系统研究以及不确定性研究。研究表明,动力-统计降尺度法和高分辨率"单一"模式及低分辨率集合相结合是HEPEX未来研究的方向。  相似文献   

13.
Basin morphometric parameters play an important role in hydrological processes, as they largely control a catchment’s hydrologic response. Their analysis becomes even more significant when studying runoff reaction to intense rainfall, especially in the case of ungauged, flash flood prone basins. Unit hydrographs are one of the useful tools for estimating runoff when instrumental data are inadequate. In this work, instantaneous unit hydrographs based on the time-area method have been compiled along the drainage networks of two small rural catchments in Greece, situated approximately 25 km northeast of its capital, Athens. The two catchments drained by ephemeral torrents, namely Rapentosa and Charadros, have been subject to flash flooding during the last decades, which caused extensive damages at the local small towns of Marathon and Vranas. Hydrograph compilation in numerous locations along the catchments’ drainage networks directly reflected the runoff conditions across each basin against a given rainfall. This gave a holistic assessment of their hydrologic response, allowing the detection of areas where peak flow rates were elevated and therefore, there was higher flood potential. The resulting flood hazard zonation showed good correlation with locations of damages induced by past flood events, indicating that the method can successfully predict flood hazard spatial distribution. The whole methodology was based on geographic information software due to its excellent capabilities on storing and processing spatial data.  相似文献   

14.
马辉  舒栋才  李薇 《水文》2016,36(4):76-79
将水文站的虹吸式雨量计全部替换为无人值守的翻斗式遥测雨量计,极大地缩短了降水信息传播时间,但由于翻斗式遥测雨量计分辨率(0.5mm)与虹吸式雨量计分辨率(0.1mm)不同,其观测资料的一致性将受到影响。通过对贵州省黔南州三个水文站各种时段不同观测精度降水特征值的对比,定量分析了其误差范围,可为水文资料的一致性分析提供参考。  相似文献   

15.
中国城市洪涝问题及成因分析   总被引:6,自引:0,他引:6       下载免费PDF全文
随着经济社会的发展,中国步入城镇化快速发展的阶段,城镇化率已由2000年的36.22%增加到2014年的54.77%。在全球气候变化与快速城镇化背景下,中国城市洪涝灾害日益严重。阐述了全球气候变化及城镇化对城市降水和极端暴雨的影响机制,并从流域产汇流角度分析了城镇化对洪水过程的影响,系统剖析了中国城市洪涝频发的主要原因。在成因分析的基础上,进一步提出了中国城市洪涝防治的应对策略,主要包括:①以低影响开发理念为指导,加强城市基础设施建设,建设海绵城市;②建立城市洪涝立体监测、预报预警和实时调度系统,强化城市洪涝科学决策能力;③健全和完善城市洪涝应急预案,强化应急管理能力,完善灾害救助和恢复机制。  相似文献   

16.
刘萍  赵雪花  王超  李新华 《地下水》2013,(6):130-132
水情自动测报系统在水资源系统管理中发挥着十分重要的作用。针对该系统在盘石头水库管理中站网布设、系统硬件组成、数据采集系统、洪水预报系统、洪水调度系统等应用技术进行详实分析,运行演示软件系统进行实例分析,达到了较高的预报精度。水情自动测报系统不仅能在汛期起到防洪减灾作用,而且在也可用于日常的水资源管理,可以起到增加蓄水和发电量,达到优化调度的目的,从而提高水利工程的社会效益和经济效益。  相似文献   

17.
This paper deals with the presentation of a flood warning system (GFWS) developed for the specific characteristics of the Guadalhorce basin (3,200 km2, SE of Spain), which is poorly gauged and often affected by flash and plain floods. Its complementarity with the European flood alert system (EFAS) has also been studied. At a lower resolution, EFAS is able to provide a flood forecast several days in advance. The GFWS is adapted to the use of distributed rainfall maps (such as radar rainfall estimates), and discharge forecasts are computed using a distributed rainfall–runoff model. Due to the lack of flow measurements, the model parameters calibrated on a small watershed have been transferred in most of the basin area. The system is oriented to provide distributed warnings and fulfills the requirements of ungauged basins. This work reports on the performance of the system on two recent rainfall events that caused several inundations. These results show how the GFWS performed well and was able to forecast the location and timing of flooding. It demonstrates that despite its limitations, a simple rainfall–runoff model and a relatively simple calibration could be useful for event risk management. Moreover, with low resolution and long anticipation, EFAS appears as a good complement tool to improve flood forecasting and compensate for the short lead times of the GFWS.  相似文献   

18.
Since tropical rainfall is important in the global energy and hydrologic cycle, the tropical rainfall changes under global warming have attracted extensive attention around the world in recent decades. The advances in the observational studies and model projection for the tropical rainfall changes under global warming were reviewed here. The frontiers in the mechanism of regional tropical rainfall changes and the approaches of rainfall change research are summarized. The large intermodel spread in the multi-model projections, the sources of uncertainty and the methods to reduce the uncertainty were also introduced. Finally, the challenges about the tropical rainfall changes were discussed.  相似文献   

19.
以山洪影响调查成果为基础,评价了昌江芦溪河段受洪水影响的程度,建立了水位预警指标体系和水文预报模型。得出的主要结论有:昌江芦溪河段洪水影响机率不到5年一遇,罗村最典型,个别年份重复受灾,属典型的山洪影响威胁区;以既有水文站点为基础,建立了水文站点的水位与上下游村落淹没基础信息的量化关联,形成"1对N"的预警关联体系,标定了集合对象的成灾水位(75.50m),分析结论与实际调查结果吻合;研究了昌江流域产汇流规律,建立了预报模型。本文的评价思路与预警体系构架方法可以作为完善山洪灾害非工程措施、中小河流水文监测系统实际应用的参考,对各地正在开展的山洪灾害调查评价工作具有参考意义。  相似文献   

20.
基于TRMM卫星雷达降雨的流域陆面水文过程   总被引:12,自引:2,他引:10       下载免费PDF全文
利用热带降雨观测计划(TRMM)卫星雷达降雨数据驱动分布式陆面水文模型,研究流域尺度陆面水文过程,评估该数据在水文模拟与预报等研究领域的性能。通过与实测雨量资料比较,验证TRMM卫星雷达降雨数据的质量。分别将TRMM卫星雷达降雨与观测降雨作为耦合模型的气象输入,模拟和研究淮河流域1998~2003年的陆面水文过程时空变化。结果表明,TRMM卫星雷达降雨数据能够很好地描述降雨的时空分布,利用TRMM降雨模拟的结果与利用观测降雨模拟的结果精度相当;模拟流量与实测资料基本吻合。卫星雷达降雨数据在陆面水文过程研究中具有广泛的应用前景。  相似文献   

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