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Now showing 1 - 8 of 8
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    Hydrological extremes and security
    (Göttingen : Copernicus GmbH, 2015) Kundzewicz, Z.W.; Matczak, P.
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    Assessing the influence of the Merzbacher Lake outburst floods on discharge using the hydrological model SWIM in the Aksu headwaters, Kyrgyzstan/NW China
    (Chichester : John Wiley and Sons Ltd, 2013) Wortmann, M.; Krysanova, V.; Kundzewicz, Z.W.; Su, B.; Li, X.
    Glacial lake outburst floods (GLOF) often have a significant impact on downstream users. Including their effects in hydrological models, identifying past occurrences and assessing their potential impacts are challenges for hydrologists working in mountainous catchments. The regularly outbursting Merzbacher Lake is located in the headwaters of the Aksu River, the most important source of water discharge to the Tarim River, northwest China. Modelling its water resources and the evaluation of potential climate change impacts on river discharge are indispensable for projecting future water availability for the intensively cultivated river oases downstream of the Merzbacher Lake and along the Tarim River. The semi-distributed hydrological model SWIM was calibrated to the outlet station Xiehela on the Kumarik River, by discharge the largest tributary to the Aksu River. The glacial lake outburst floods add to the difficulties of modelling this high-mountain, heavily glaciated catchment with poor data coverage and quality. The aims of the study are to investigate the glacier lake outburst floods using a modelling tool. Results include a two-step model calibration of the Kumarik catchment, an approach for the identification of the outburst floods using the measured gauge data and the modelling results and estimations of the outburst flood volumes. Results show that a catchment model can inform GLOF investigations by providing 'normal' (i.e. without the outburst floods) catchment discharge. The comparison of the simulated and observed discharge proves the occurrence of GLOFs and highlights the influences of the GLOFs on the downstream water balance.
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    Flood risk governance arrangements in Europe
    (Göttingen : Copernicus GmbH, 2015) Matczak, P.; Lewandowski, J.; Choryński, A.; Szwed, M.; Kundzewicz, Z.W.
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    Understanding flood regime changes in Europe: A state-of-the-art assessment
    (Göttingen : Copernicus GmbH, 2014) Hall, J.; Arheimer, B.; Borga, M.; Brázdil, R.; Claps, P.; Kiss, A.; Kjeldsen, T.R.; Kriauĉuniene, J.; Kundzewicz, Z.W.; Lang, M.; Llasat, M.C.; Macdonald, N.; McIntyre, N.; Mediero, L.; Merz, B.; Merz, R.; Molnar, P.; Montanari, A.; Neuhold, C.; Parajka, J.; Perdigão, R.A.P.; Plavcová, L.; Rogger, M.; Salinas, J.L.; Sauquet, E.; Schär, C.; Szolgay, J.; Viglione, A.; Blöschl, G.
    There is growing concern that flooding is becoming more frequent and severe in Europe. A better understanding of flood regime changes and their drivers is therefore needed. The paper reviews the current knowledge on flood regime changes in European rivers that has traditionally been obtained through two alternative research approaches. The first approach is the data-based detection of changes in observed flood events. Current methods are reviewed together with their challenges and opportunities. For example, observation biases, the merging of different data sources and accounting for nonlinear drivers and responses. The second approach consists of modelled scenarios of future floods. Challenges and opportunities associated with flood change scenarios are discussed such as fully accounting for uncertainties in the modelling cascade and feedbacks. To make progress in flood change research, we suggest that a synthesis of these two approaches is needed. This can be achieved by focusing on long duration records and flood-rich and flood-poor periods rather than on short duration flood trends only, by formally attributing causes of observed flood changes, by validating scenarios against observed flood regime dynamics, and by developing low-dimensional models of flood changes and feedbacks. The paper finishes with a call for a joint European flood change research network.
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    Extreme hydrological events and security
    (Göttingen : Copernicus GmbH, 2015) Kundzewicz, Z.W.; Matczak, P.
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    Climate change track in river floods in Europe
    (Göttingen : Copernicus GmbH, 2015) Kundzewicz, Z.W.
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    Flood risk and climate change: global and regional perspectives
    (Milton Park : Taylor and Francis Ltd., 2014) Kundzewicz, Z.W.; Kanae, S.; Seneviratne, S.I.; Handmer, J.; Nicholls, N.; Peduzzi, P.; Mechler, R.; Bouwer, L.M.; Arnell, N.; Mach, K.; Muir-Wood, R.; Brakenridge, G.R.; Kron, W.; Benito, G.; Honda, Y.; Takahashi, K.; Sherstyukov, B.
    A holistic perspective on changing rainfall-driven flood risk is provided for the late 20th and early 21st centuries. Economic losses from floods have greatly increased, principally driven by the expanding exposure of assets at risk. It has not been possible to attribute rain-generated peak streamflow trends to anthropogenic climate change over the past several decades. Projected increases in the frequency and intensity of heavy rainfall, based on climate models, should contribute to increases in precipitation-generated local flooding (e.g. flash flooding and urban flooding). This article assesses the literature included in the IPCC SREX report and new literature published since, and includes an assessment of changes in flood risk in seven of the regions considered in the recent IPCC SREX report-Africa, Asia, Central and South America, Europe, North America, Oceania and Polar regions. Also considering newer publications, this article is consistent with the recent IPCC SREX assessment finding that the impacts of climate change on flood characteristics are highly sensitive to the detailed nature of those changes and that presently we have only low confidence1 in numerical projections of changes in flood magnitude or frequency resulting from climate change.
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    Adapting flood preparedness tools to changing flood risk conditions: The situation in Poland
    (Sopot : Polish Academy of Sciences, 2014) Kundzewicz, Z.W.
    Flooding is the most destructive natural hazard in the Baltic Sea Basin in general and in Poland in particular. The notion includes floods from rivers and mountain torrents, as well as floods from sea surges in coastal areas, and floods from sewage systems. There have been several large floods in Poland in the last century and in recent decades, with damage exceeding 1% of the Polish GDP. The spatial and temporal characteristics of the flood risk in Poland are reviewed and observations and projections of changes in the flood hazard in the country are discussed. Furthermore, flood defences and flood preparedness systems in Poland are examined, with particular reference to the European Union (EU) Floods Directive, which is being implemented in Poland, an EU country. Finally, the public debate on flood risk and flood preparedness is reviewed.