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Download or read book Task 7, River Floods : written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1980 river floods in Europe have resulted in over 4,700 fatalities and caused direct economic losses of more than €150 billion (2013 values), and future risk is likely to increase due to the combination of climatic and socio-economic drivers. As such, reliable research works are needed to investigate river flood risk under future climate scenarios, and to evaluate adaptation strategies able to limit the impacts of river flooding. In this report, we present results of the PESETA III river flood risk assessment based on an ensemble of high-resolution regional climate scenarios and suitable socio-economic pathways. We evaluated river flood risk in Europe throughout the 21st century by comparing flood impacts under baseline (1976-2005) climate with those in the near (2021-2050) and far (2071-2100) future and under specific warming levels (SWLs) of 1.5, 2 and 3°C global warming above preindustrial levels. Simulated flood risk scenarios are representative for high levels of greenhouse gas concentrations in the atmosphere, and considering both time-based and warming-based scenarios allows to evaluate the influence of the speed of warming on flood impacts. Our analysis includes all EU member states plus a number of neighbouring countries, most of which include parts of European river basins like the Danube. The neighbour countries considered are Bosnia - Herzegovina, Belarus, Iceland, Kosovo, Moldova, Montenegro, the Republic of Macedonia (FYROM), Norway, Serbia and Switzerland. An ensemble of seven regional climate projections from 1970 to 2100 forced by the Representative Concentration Pathway (RCP) 8.5 scenario were run through a distributed hydrological model and resulting streamflow was analysed statistically to estimate future changes in the river flood hazard in Europe. Note that the analysis does not consider other flood processes such as coastal floods (due to storm surges and waves), nor pluvial and flash floods (caused by localized, high-intensity rainfall events). Impacts of river floods in Europe were evaluated by combining the occurrence and magnitude of future discharge peaks with present exposure maps (population, landuse) and information on flood defences. Estimates of expected economic damage and population affected were produced considering first only climatic drivers (static economic analysis) and then including the effects of socio-economic development coherent with the considered climate scenarios (dynamic economic analysis). Furthermore, the risk assessment framework was applied to qualitatively evaluate the risk reduction potential of a number of flood adaptation strategies. Measures taken into account include the rise of flood protection, reduction of the peak flows through water retention, reduction of vulnerability and relocation to safer areas. Under baseline climate, in Europe around 216,000 people are exposed each year to river flooding and annual flood damage amounts to €5.3 billion. In most regions of Europe we see an increase of flood risk due to global warming (see Figure 1). Under a 2°C global warming scenario, which under the RCP8.5 pathway will occur in the early 2040s, and considering current socio-economic conditions, flood impacts could more than double, with 525,000 people annually exposed to floods and €13 billion of expected annual losses. If near term (2021-2050) climate conditions are considered, approximately 450,000 people could be exposed annually to river flooding and direct flood damages could reach €12 billion. Longer term climate conditions (2071-2100) imposed on present society could result in over 700,000 people annually exposed to floods while direct flood damages could see a more than three-fold increase with respect to current conditions, reaching €17 billion of average annual losses.