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1.
Flood and sediment disasters caused by glacial lake outbursts have occurred frequently in recent years in the Himalayas of Nepal. Glacial lake outburst floods (GLOFs) can cause catastrophic flooding in downstream areas with serious damage to lives and property. It is thus important to investigate outburst floods from potentially dangerous glacial lakes. In this study, the characteristics of potential outburst floods from the Tsho Rolpa glacial lake due to two types of moraine dam failure caused by seepage flow or water overtopping were analyzed with various scenarios by using integrated modeling system of three numerical models: (1) the flow and bed-surface erosion model, (2) the seepage model and (3) the slope stability model. Flood inundation areas were also identified by using the numerical model of the flow and moraine dam failure and geographical information system tools. Possible threats and damages due to the potential GLOF events from the lake were also analyzed based on numerical results, flood inundation maps and field investigations. 相似文献
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末次冰期以来,气候变暖导致全球高山地区的冰川环境变化剧烈,冰碛湖稳定性降低导致溃决频率增加,成为中国、尼泊尔、俄罗斯、秘鲁等10多个国家和地区频繁发生的冰川灾害类型之一。冰碛湖溃决诱发形成的洪水和泥石流,由于规模巨大、成灾速度快和波及范围广等特点,造成下游地区的基础设施和生命财产遭受惨重损失。本文通过对国内外冰碛湖溃决事件、溃决诱因、溃决模式和溃决洪水特征4个方面研究现状和发展现状的梳理和分析,总结经验和思路,从而为冰碛湖溃决研究和评价提供借鉴和参考。 相似文献
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Flood events have the highest damage costs and losses among natural hazards. There are different types of measures to mitigate flood damage costs and their negative consequences. Application of flood-control reservoirs or detention dams, as one of the main measures, may decrease devastating flood effects or even may cause to intensify flood damages in the watershed by a poor design with tremendous construction costs. Optimal design of a flood-control multi-reservoir system can simultaneously minimize investment costs of constructions and potential flood damage costs. This study proposes a simulation-based optimization approach to optimize the design of multi-reservoirs for flood control in the watershed by coupling the MIKE-11 hydrodynamic model and the NSGA-II multi-objective optimization model. The present approach provides the Pareto optimal solutions between two conflict objectives of minimizing total investment costs and the expected flood damage costs in the watershed. Application of the proposed model for a small watershed in central part of Iran as a case study shows that optimal designs of multi-reservoir systems can efficiently reduce construction costs, flood peaks and their corresponding damage costs at the downstream reaches of the basin. 相似文献
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Turkey has been severely affected by many natural hazards, in particular earthquakes and floods. Especially over the last two decades, these natural hazards have caused enormous human and economic damage. Although there is a large body of literature on earthquake hazards and risks in Turkey, comparatively little is known about flood hazards and risks. Therefore, this study aims to investigate the severity of flooding in comparison with other natural hazards in Turkey and to analyse the flood patterns by providing an overview of the temporal and spatial distribution of flood losses. These will act as a metric for the societal and economic impacts of flood hazards in Turkey. For this purpose, Turkey Disaster Database (TABB) was used for the years 1960–2014. As input for more detailed event analyses, the most severe flood events in Turkey for the same time interval will also be retrieved. Sufficiency of the TABB database to achieve the main aim of the study in terms of data quality and accuracy was also discussed. The TABB database was analysed and reviewed through comparison, mainly with the Emergency Events Database (EM-DAT), the Global Active Archive of Large Flood Events—Dartmouth Flood Observatory database, news archives and the scientific literature, with a focus on listing the most severe flood event. The comparative review of these data sources reveals big mismatches in the flood data, i.e. the reported number of events, number of affected people and economic loss all differ dramatically. Owing to the fact that the TABB is the only disaster loss database for Turkey, it is important to explore the reasons for the mismatches between TABB and the other sources with regard to aspects of accuracy and data quality. Therefore, biases and fallacies in the TABB loss data are also discussed. The comparative TABB database analyses show that large mismatches between global and national databases can occur. Current global and national databases for monitoring losses from national hazards suffer from a number of limitations, which in turn could lead to misinterpretations of the loss data. Since loss data collection is gaining more and more attention, e.g. in the Sendai Framework for Disaster Risk Reduction 2015–2030, this study offers a framework for developing guidelines for the Turkey Disaster Database (TABB), implications on how to standardize national loss databases and implement across the other hazard events in Turkey. 相似文献
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This article attempts to analyse the nature, magnitude and causes of 2010 disastrous flood that seriously affected the province of Khyber Pakhtunkhwa (KPK), Pakistan. Pakistan is famous for its summer floods, but the flood of 2010 is considered to be the century’s worst. It has broken all the previous records in terms of discharge, damages and amount of rainfall occurred. Most of the meteorological stations have received rainfall above normal. Data for this study were collected both from primary and secondary sources. A total 150 questionnaires were filled in from the flood victims. However, secondary data were obtained from the Pakistan Meteorology Department, Flood Forecasting and Warning Centre, Federal Flood Commission, Provincial Disaster Management Authority, National Disaster Management Authority, Surface Water Hydrology Department and Provincial Irrigation and Drainage Authority. The analysis reveals that heavy and prolonged rainfall for four consecutive days (27–30 July) was the major cause of 2010-flood. In addition to this, the development of unusual low pressure zone over the northern Pakistan, aggradations of river bed, rapid deforestation, ponding back of river by motorway, blocking of bridges by tree trunks and subsequent bursting of temporary dams have played their role in causing the disastrous flood in almost all the rivers of KPK. This has inflicted terrible damages to human lives, standing crops, housing, infrastructure and other properties. 相似文献
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Kanchan Pande 《Journal of Earth System Science》2002,111(2):115-115
A review of the available radiometric and paleomagnetic data from the Deccan Flood Basalt Province (DFBP) suggests that the
volcanism was episodic in nature and probably continued over an extended duration from 69 Ma to 63 Ma between 31R and 28N.
It is likely that the most intense pulse of volcanism at 66.9 ± 0.2 Ma preceded the Cretaceous Tertiary Boundary (KTB, 65.2
± 0.2Ma) events by R∼1.7Ma. The magnetostratigraphic record in the Deccan lava pile is incomplete and it is therefore possible
that the lava flows constituting the reverse polarity sequence were erupted in more than one reversed magnetic chron. 相似文献
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考虑暴雨成因的大伙房水库洪水分类研究 总被引：2，自引：1，他引：1
暴雨洪水形成机制十分复杂,它既具有随机性,又具有确定性.可是现行的流域防洪调度设计中强调的是随机性,忽略了客观上存在的确定性,因此使得设计结果与实际脱节,不能充分发挥防洪与兴利效益.本文针对这一问题,考虑到特定流域内产生暴雨的天气系统所具有的相对稳定性规律,及其形成的暴雨洪水过程存在的确定性关系,以大伙房水库流域为例,归纳出依据暴雨成因对流域内洪水过程分类的方法.通过各类洪水过程线图及各类洪水过程相似性系数计算,证明了洪水过程分类的合理性.这种分类,对了解流域洪水规律,提高水库防洪能力、提高洪水资源利用率,及深入研究水库防洪分类预报调度方式设计具有重要的现实意义. 相似文献
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Pradeep Adhikari Yang Hong Kimberly R. Douglas Dalia Bach Kirschbaum Jonathan Gourley Robert Adler G. Robert Brakenridge 《Natural Hazards》2010,55(2):405-422
Floods have profound impacts on populations worldwide in terms of both loss of life and property. A global inventory of floods
is an important tool for quantifying the spatial and temporal distribution of floods and for evaluating global flood prediction
models. Several global hazard inventories currently exist; however, their utility for spatiotemporal analysis of global floods
is limited. The existing flood catalogs either fail to record the geospatial area over which the flood impacted or restrict
the types of flood events included in the database according to a set of criteria, limiting the scope of the inventory. To
improve upon existing databases, and make it more comprehensive, we have compiled a digitized Global Flood Inventory (GFI)
for the period 1998–2008 which also geo-references each flood event by latitude and longitude. This technical report presents
the methodology used to compile the GFI and preliminary findings on the spatial and temporal distributions of the flooding
events that are contained in the inventory. 相似文献
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Li Chang’an Yin Hongfu Zhang Yufen Gu Yansheng Faculty of Earth Sciences China University of Geosciences Wuhan China 《中国地质大学学报(英文版)》2000,11(3)
CAUSE FOR FL OODS IN MIDDL E REACH OF YANGTZERIVERFlood,a kind of interface disaster,occurs atthe interfacebetween atmosphere and lithosphere. Flood happens when at-mosphere and lithosphere interplay and couple each other(ofcourse,biosphere may also join in this) . Both meteorologicaland geographical factors can bring about flood;the formercontrols the time of flood and the latter controls the place ofdisaster. The second Neocathaysian tectonic subsidence area(L i,1973) is the… 相似文献
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土石坝漫顶溃决往往在其下游产生巨大的洪水灾难,研究坝体溃决及洪水演进是防灾减灾的需要。对土石坝漫顶溃决过程现象、机理及其模拟的研究进展进行了综述。讨论了物理模型试验的尺度设计,总结了不同尺度、不同类型、不同条件溃坝试验的研究成果;按照参数模型、简化物理模型、精细物理模型,分类总结了漫顶溃坝数学模型研究进展;阐述了溃坝洪水演进方面的试验与模拟研究。在此基础上,对该研究领域今后的研究工作提出了若干展望,包括河道边界对溃坝过程及溃坝洪水传播过程的影响、非均质土石坝溃决机理、溃坝过程中挟沙水流冲蚀规律、溃坝下游河床的冲淤调整及泥沙分选、溃坝对水生态环境的冲击影响等。 相似文献
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土石坝漫顶溃决往往在其下游产生巨大的洪水灾难,研究坝体溃决及洪水演进是防灾减灾的需要。对土石坝漫顶溃决过程现象、机理及其模拟的研究进展进行了综述。讨论了物理模型试验的尺度设计,总结了不同尺度、不同类型、不同条件溃坝试验的研究成果;按照参数模型、简化物理模型、精细物理模型,分类总结了漫顶溃坝数学模型研究进展;阐述了溃坝洪水演进方面的试验与模拟研究。在此基础上,对该研究领域今后的研究工作提出了若干展望,包括河道边界对溃坝过程及溃坝洪水传播过程的影响、非均质土石坝溃决机理、溃坝过程中挟沙水流冲蚀规律、溃坝下游河床的冲淤调整及泥沙分选、溃坝对水生态环境的冲击影响等。 相似文献
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《Comptes Rendus Geoscience》2008,340(9-10):644-650
The knowledge of past catastrophic events can improve flood risk mitigation policy, with a better awareness against risk. As such historical information is usually available in Europe for the past five centuries, historians are able to understand how past society dealt with flood risk, and hydrologists can include information on past floods into an adapted probabilistic framework. In France, Flood Risk Mitigation Maps are based either on the largest historical known flood event or on the 100-year flood event if it is greater. Two actions can be suggested in terms of promoting the use of historical information for flood risk management: (1) the development of a regional flood data base, with both historical and current data, in order to get a good feedback on recent events and to improve the flood risk education and awareness; (2) the commitment to keep a persistent/perennial management of a reference network of hydrometeorological observations for climate change studies. 相似文献
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Floods in Malaysia have been increasing in frequency and magnitude as reflected in the Kelantan Flood event in 2014 that resulted in a huge loss of lives and properties. Whereas remote sensing (RS) and geographical information system (GIS) tools have been extensively applied in flood disaster management, there are few reports and studies on the impact of floods on the land use/land cover environment in a post-disaster assessment. In this study, an integrated modelling approach was developed that used Landsat 8 OLI TIRS (Operational Land Imager (OLI) and Thermal Infrared Sensor) data, flood indexing and classification processes to estimate the impact of flood on the environment. The Normalized Difference Flood Index-3 (NDFI3) is an improvement on NDFI2 that takes into account the effects of cloud shadow in the images when extracting flood index areas. The flood model developed showed good agreement when compared with flooded areas shown in SAR (synthetic-aperture radar) image. The results of the flood extent as a proxy for damage estimation showed that the total flooded area was 502.34 km2 for the Kelantan Flood event in 2014, with plantation and built-up area accounting for 43 and 34.6% respectively. The least affected land uses/land covers were deforested area and forest, which accounted for 12.2 and 10.2% respectively. The RS and GIS technique developed in this post-disaster damage assessment is effective, relatively inexpensive and simple to implement by local authorities in support of post-flood disaster planning and decision-making. 相似文献
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The paper analyses the hydrological regime of the Rhine catchment,the genesis of recent floods,and recommends some research and practical activities to mitigate flood damage. The catchment of the Rhine River can be divided into four main subcatchments: the alpine region with the Aare River as its main tributary and downstream the lower mountain regions of the tributaries Neckar, Main and Moselle. These four basins generate very different hydrographs. Due to the geographical conditions, the average discharge maximums shift from summer to winter downstream the Rhine. Moreover, the spatial and temporalprecipitation patterns of each river have a strong influence on the individual flood events. Some recent extraordinary floods are used to illustrate the parameters that have influenced these events.A strong relationship between recent climate change observationsand the occurrence of flood levels cannot be proven. However, the consequences of human interventions and the resulting changes to the river system (the Rhine and its tributaries) for the hydrograph can be quantified precisely.The influences of different land-use and climatic scenarios on flood conditions in the Rhine basin have not yet been separately identified. Thus, the Dutch-German project LAHoR was established. The primary aim of this project is to giveadvice for the ``Action Plan on Flood Defence' of the International Commission for the Protection of the Rhine (IKSR). In this plan a multidisciplinary approach to mitigating floods is suggested.It is anticipated that the plan willgenerate synergistic effects between flood prevention, water management, regional planning, agriculture, forestry and ecological demands. 相似文献
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Flood is the worst weather-related hazard in Taiwan because of steep terrain and storm. The tropical storm often results in disastrous flash flood. To provide reliable forecast of water stages in rivers is indispensable for proper actions in the emergency response during flood. The river hydraulic model based on dynamic wave theory using an implicit finite-difference method is developed with river roughness updating for flash flood forecast. The artificial neural network (ANN) is employed to update the roughness of rivers in accordance with the observed river stages at each time-step of the flood routing process. Several typhoon events at Tamsui River are utilized to evaluate the accuracy of flood forecasting. The results present the adaptive n-values of roughness for river hydraulic model that can provide a better flow state for subsequent forecasting at significant locations and longitudinal profiles along rivers. 相似文献
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Four stratigraphic sections in the southern part of the Columbia Basin preserve a sequence of aeolian and non-aeolian sediments ranging in age from 9·43 to >47·0 14 C ka based on accelerator mass spectrometry radiocarbon dating of fossil molluscs, geochemistry of Cascade Mountain-sourced tephra and association with formally recognized pedostratigraphic units (the Washtucna and Old Maid Coulee soils). Study sections are interpreted as representing concurrent deposition of loess and distal Missoula Flood rhythmites in valleys tributary to main drainages backflooded during the Missoula Floods, and formation of carbonate and iron-rich soils. Sediments belong to the formally recognized L-1 and L-2 loess units established for the Palouse loess, which were deposited in the Columbia Basin subsequent to events of glacial outburst flooding. Sediments associated with the Mount Saint Helens set S and set C tephras in the study sections preserve a fauna of five species of gastropod mollusc which have not been reported previously from sediments of late Pleistocene age in the Palouse region. The fossils comprise two distinct faunules stratigraphically separated by the Mount Saint Helens So tephra. Accelerator mass spectrometry radiocarbon dating of the fossils collected above the tephra in two of the sections yielded ages of 12·48 ± 0·06 and 9·43 ± 0·05 14 C kyr. These ages suggest that independent determinations of the 13·35 14 C kyr age of the So tephra in other areas where Missoula Flood sediments are preserved are probably accurate, and help to refine the age of the latest events in the most recent sequence of catastrophic glacial outburst flooding. 相似文献
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Ellis L. Krinitzsky 《Engineering Geology》2005,76(3-4):295-311
Flood stories in the Hebrew Bible and the Koran appear to be derived from earlier flood stories like those in the Gilgamesh Epic and still earlier in the Atrahasis. All would have their source from floods of the Tigris and Euphrates rivers.
The Gilgamesh Epic magnifies the catastrophe by having the flood begin with winds, lightning, and a shattering of the earth, or earthquake. Elsewhere in Gilgamesh, an earthquake can be shown to have produced pits and chasms along with gushing of water. It is commonly observed that earthquake shaking causes water to gush from the ground and leaves pits and open fissures. The process is known as soil liquefaction. Earthquake is also a possible explanation for the verse “all the fountains of the great deep (were) broken up” that began the Flood in Genesis. Traditionally, the “great deep” was the ocean bottom. A more recent translation substitutes “burst” for “broken up” in describing the fountains, suggesting that they erupted at the ground surface and were caused by an earthquake with soil liquefaction. Another relation between soil liquefaction and the Flood is found in the Koran where the Flood starts when “water gushed forth from the oven”. Soil liquefaction observed erupting preferentially into houses during an earthquake provides a logical interpretation if the oven is seen as a tiny house. A case can be made that earthquakes with soil liquefaction are embedded in all of these flood stories. 相似文献