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W literaturze światowej i polskiej znaleźć można wiele charakterystyk oraz wskaźników opisu suszy i innych mówiących o potrzebach wodnych. Ich zastosowanie zależy głównie od celu oraz dostępności danych. Przedstawiane są one w różnych skalach przestrzennych i czasowych, od skali regionalnej do globalnej. Często służą one do podejmowania decyzji w rolnictwie i gospodarce. Takie zastosowanie narzuca podejście metodyczne tzn. otrzymane wyniki powinny być porównywalne dla różnych obszarów. W związku z powyższym wskaźniki suszy najczęściej wyrażone są jako pojedyncza wartość odnoszona do wybranego obszaru, czy zlewni. Niektóre wskaźniki, najprostsze do określenia, mówią o różnicy sumy opadu z analizowanego przedziału czasowego i norm ustalonych ma podstawie materiału historycznego. Inne wykorzystują więcej informacji np. o temperaturze, pokrywie śnieżnej, zasilaniu wodami powierzchniowymi i podziemnymi itp. Mimo, że trudno ocenić, który wskaźnik jest najlepszy, dla każdego obszaru można znaleźć taki, który lepiej opisuje dane warunki przyrodnicze i klimatyczne. W pracy zamieszczono przegląd wskaźników opisu suszy szeroko stosowanych na świecie i w Polsce oraz przedstawiono wyniki zastosowania wybranych wskaźników dla obszaru zlewni Nysy Kłodzkiej.
Awareness of the potential threat of significant natural hazards necessitates the introduction of appropriate procedures allowing for effective and systematic actions aimed at eliminating, or at least partially limiting the effects of such events. Due to the nature of drought and the complex process of its development, the cause and effect approach is widely used in assessing droughts. Naturally, this leads to the treatment of drought in terms of risk, which is defined as a derivative of hazards and consequences. Thus formulated definition of drought leads, in a broader context, to endeavours at minimizing the effects and reducing the size of losses, taking into account the prioritization of activities. An active drought risk management policy is necessary to achieve the safety of water resources in the face of current climate threats and expected further changes. The aim of this work is to present the original concept of drought risk assessment for the needs of strategic risk management as an integrated approach to the implementation of the drought management plan. Risk management is crucial and necessary to effectively reducing the effects of drought in a sustainable manner, in the context of meeting the needs of the population, the environment, and the economy. Risk management is a continuous process, consisting of logically arranged, consecutive events, actions, decisions and approvals, repeated cyclically in the course of monitoring the achieved results and implementing optional adaptations to the observed and forecasted changes. The risk management system presented in the work creates an organizational, methodical and functional framework, the implementation of which in the form of structural and IT solutions may be a tool for effective operation of plans aimed at counteracting the effects of drought on the level of particular water regions and river catchments. The proposed approach, based on strategic management in pursuit of sustainable assurance of water safety for social and natural systems, ensures durability of services of freshwater ecosystems responsible for maintaining biodiversity, maintaining life processes and regeneration of the environment, as well as providing people with economic benefits. The integrated SPI-SRI index of coexistence of humidity conditions was used to assess the risk of drought. The aforementioned index made it possible to determine the likelihood of a drought in probabilistic terms, including the phase of atmospheric and hydrological drought in a given basin, which is a key element in drought risk assessment. The estimated period of repeatability of the threat of dry or very dry meteorological conditions leading to hydrological drought in the Nysa Kłodzka catchment was calculated as once every 7.2 years, and in the Prosna catchment, once every 8 years. This information can be used in planning actions aimed at minimizing the effects of drought, and in water management (for instance, on reservoirs) aimed at reducing these effects.
Flooding in East-Central Europe in May and June 2010 also affected the Odra River Basin. Unlike a typical summer flood scenario, in 2010 intensive precipitation was observed as early as May. Also, the location of the most intensive rainfall shifted to the catchments of the right bank tributaries of the Odra River. This paper presents the climatological assessment of the precipitation totals that caused two flood waves on the Odra River. The assessment was carried out with the use of selected indicators: monthly precipitation totals, daily precipitation totals, number of days exceeding given precipitation levels, number of days with precipitation of a given probability of exceedance and intensity, duration and accumulation of precipitation for a number of consecutive wet days. The reference values for climatological indicators were developed for the period 1966-2009. The values of the selected indicators were analyzed in terms of flood hazard in relation to the hazard gradation. The results show that the observed precipitation had the character of an extreme event with respect to its magnitude, duration and spatial extent. The catchments with recognized high levels of flood hazard were affected by the flood wave. The flood situation caused by the extreme precipitation was evaluated in the context of the largest floods in this region during recent decades.
Directive 2007/60/WE of the European Parliament regarding flood risk assessment and management (The Floods Directive) obliges member states to achieve certain aims within given timeframes. The member states are to prepare planning policies, i.e. flood hazard and flood risk maps, by December 2013. The maps should be based on hydraulic models. Preparing the input data includes compiling hydraulic data (the shape of and material from which a river bed and a river valley are made) and data on the hydrotechnical infrastructure and communication. A detailed survey includes bridges and other hydrotechnical structures. The article presents possible use of 3D terrestrial laser scanning (TLS) in the survey of structures where measurement using classical methods may be hazardous. And also, where the level of the structure's complexity for some of the elements is so high, that the classical survey will not deliver eligible results. As an output, there appears to be an entirely measurable 3D model, ready to be used by experts in the field of hydrology and construction.
The Archer method for construction of nonparametric hydrographs was regarded as the basic one for constructing design hydrographs in gauged cross sections. The hydrographs designed using this method belong to a group of non-formalized hydrology. Unlike the commonly used formalized methods, where a nonparametric hydrograph is strictly determined and defined, the hydrographs defined in this way are constructed on the assumption, that flow is the main determined parameter. On the other hand, the Archer method assumes that the basic parameter is time, which is determined for assigned standardized flow, called a flow percentile. Hydrographs constructed using this method are the basis for constructing parametric design hydrographs used for engineering computations. The Archer method is relatively new and should be verified for various regions. Presented manuscript compares the results obtained using this method in the middle Odra and upper Vistula basins with the nonparametric method developed at the Cracow University of Technology, called the Cracow method. The obtained results show, that four highest registered flood waves are sufficient to construct a nonparametric design hydrograph, whereas semi-standardized volumes above descriptors W75 and W50 and the duration time of the descriptors are bigger than the volumes and duration times calculated by means of the Cracow method in the Vistula River basin, and approximate with regard to the values in the Odra River basin.
Wstępna oceny ryzyka powodziowego (WORP) ma na celu oszacowanie skali zagrożenia powodziowego dla obszarów dorzeczy oraz identyfikację znaczącego ryzyka powodziowego na tych obszarach. Obszary narażone na niebezpieczeństwo powodzi zostały zidentyfikowane na podstawie przeprowadzonej inwentaryzacji na szczeblu krajowym, wojewódzkim i lokalnym. Inwentaryzacją objęto informacje o granicach obszarów zagrożenia powodzią, mapach hydrograficznych, planach zagospodarowania przestrzennego oraz o stanie technicznym budowli przeciwpowodziowych. Do przeprowadzenia inwentaryzacji wykorzystano metodę ankietyzacji. Zebrany materiał został pogrupowany i zestawiony w układzie hierarchicznym ze względu na typ powodzi, a następnie sprowadzony do jednolitego układu odniesienia i jednolitej skali. Zebrane informacje stanowią podstawę do wskazania odcinków rzek, dla których zostaną opracowane mapy za-grożenia powodziowego i mapy ryzyka powodziowego. Wstępna Ocena Ryzyka Powodziowego (WORP) została opracowana w ramach projektu „Informatyczny System Osłony Kraju przed nadzwyczajnymi zagrożeniami" (ISOK). Stanowi element wypełnienia zobowiązań Polski wobec Unii Europejskiej w zakresie wdrażania pierwszego etapu Dyrektywy Powodziowej. Prezentowany artykuł przedstawia opracowanie WORP dla obszaru górnej i środkowej Odry.
The overall objective of the ongoing work is to develop the computational environment HY DRO-PATH as a flexible tool for forecasting runoff from catchment areas for various hydrometeorological conditions while taking into account the information available on a real-time basis. Ensuring the model’s operational reliability and reducing the uncertainty of generated forecasts is accomplished through the adjustment of both the internal structure of the model and the spatial representation of the computational grid to the physiographical, hydrological and climatological characteristics of a given basin. The research focused on the development of methods for selecting the optimal model structure and parameters by analysing the results obtained for different model structures. This is achieved through the computational environment, in which it is possible to implement different types of hydrological rainfall-runoff models. These models have a unified system of data input, parameter optimisation rules, and procedures for result generation. The developed elements of the computational environment correspond to generation potential of models with a given structure and complexity. Furthermore, within the framework of HY DRO-PATH the following components were developed: an application programming interface (API), a data assimilation module, a module for computational representation of a real object, and a module for the estimation and optimisation of model parameters. The developed computational environment was applied to prepare a version of TOPO-Flex and perform hydrological validation of the model’s results. The hydrological validation was performed for selected flood events in the Bystrzyca Dusznicka subbasin of the Nysa Kłodzka River.
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