Future water availability in selected European catchments: a probabilistic assessment of seasonal flows under the IPCC A1B emission scenario using response surfaces

Abstract. A grid-based water balance model is used to quantify exceedance probabilities of high and low stream flow thresholds, and analyse their progression over the course of the 21st century. The analysis is carried out for 18 European river basins using the response surface method in combination with probabilistic projections of climate change, conditional to the IPCC A1B emission scenario up to 2100. According to this study, Nordic basins have the highest probability of high flow threshold violation in Europe, while in Central and Southern European basins, the probability of low flow threshold violation is highest. While the high flow violation occurs mostly during winter, with other seasons being likewise probable, low flow violation only occurs in summer. Some basins are facing an increased stream flow amplitude, having high probabilities for both, high flow and low flow violations.