TY - CHAP A1 - Pohle, Ina A1 - Gädeke, Anne A1 - Koch, Hagen A1 - Schümberg, Sabine A1 - Hinz, Christoph T1 - Can water resources management alleviate the uncertainty of projected climate change impacts on river discharge? - A comparative study in two hydrologically similar catchments with different level of management T2 - International Soil and Water Assessment Tool Conference. SWAT 2017, June 28 – 30, Warsaw, Poland, Book of Abstracts N2 - Climate change impact studies are associated with error propagation and amplification of uncertainties through model chains from global climate models down to impact (e.g. hydrological) models. The effect of water management, which reduces discharge variability, is often not considered in climate change impact studies. Here, we investigated how water resources management influences discharge variability and uncertainty propagation of climate change scenarios by combining the analyses of observed flow records and model-based climate change impact simulations. Two neighbouring catchments, the Schwarze Elster River (Germany) and the Spree River (Germany and Czech Republic) which are similar in climate, topography and land use, but different in terms of water resources management were chosen as study area. The intense water resources management in the Spree River catchment includes a high reservoir capacity, water use in terms of mining discharges and water withdrawals by power plants as well as water transfers. The analysis of historical flow records focusses on variability indices (Parde index, Richards-Baker-Flashiness Index, Interquartile Ratio and Baseflow Index). The climate change impact simulations were carried out using a model cascade of (i) the statistical regional model STAR (100 stochastically generated realizations each for 3 scenarios with different prescribed temperature trend), (ii) the hydrological models SWIM and EGMO, and (iii) the water resources management model WBalMo. The analysis of the observed discharges reveals that the annual discharge variability in the Spree catchment is dominated by mining activities rather than natural rainfall-runoff processes. Due to the high reservoir capacity in the Spree catchment its discharge is characterised by less seasonality and short-term variability compared to the Schwarze Elster. Simulations with climate change scenarios assuming increasing temperature and decreasing precipitation result in pronounced reductions of discharge in both catchments. The differences in potential natural discharges between the Schwarze Elster and the Spree catchments as projected by the hydrological models SWIM and EGMO are marginal. The uncertainties related to the climate projection are propagated through the hydrological models. In the Schwarze Elster catchment, the managed discharges simulated by WBalMo are comparable to the potential natural discharges. In the Spree River however, the short-term variability is moderated by water resources management and managed discharge under climate change is less affected by amplification of uncertainties through model chains. The results of the study, which combines the analyses of observed flow records and model-based climate change impact simulations, imply that generally, effective water resources management reducing discharge variability hence also reduces uncertainty related to climate change impacts on river discharge. Catchments with a high storage ratio are thus less vulnerable to changing climate conditions. This underlines the role of water resources management in coping with climate change impacts. Yet, due to decreasing reservoir volumes in drought periods, reservoir management alone cannot compensate strong changes in climate conditions over long time periods. KW - SWIM KW - climate change KW - uncertainty KW - water resources management KW - model comparison Y1 - 2017 UR - http://swat.tamu.edu/media/115571/book-of-abstracts-2017-06-25.pdf SP - 10 EP - 11 ER - TY - GEN A1 - Pohle, Ina A1 - Gädeke, Anne A1 - Schümberg, Sabine A1 - Hinz, Christoph A1 - Koch, Hagen T1 - Management Influences on Stream-Flow Variability in the Past and Under Potential Climate Change in a Central European Mining Region T2 - Water Resource Management N2 - Robust assessments of stream-flow volume and variability under current and potential future conditions are essential for sustainable water resources planning and management. Nonlinear and overlapping responses to climate, land use, and water resources management (WRM) make it difficult to link observed stream-flow variability to individual drivers and to project potential future changes in stream-flow volume and variability. Here, we investigate WRM influences on stream-flow variability for two rivers with similar natural catchment characteristics, the Schwarze Elster and the Spree. The Schwarze Elster is characterized by less intensive WRM compared to the Spree. Management influences on stream-flow variability in the past were analysed by comparing observed managed stream-flow with simulated natural flow (model SWIM). Simulation results of natural flow and managed stream-flow (model WBalMo) forced by different climate scenarios were investigated to assess management influences on potential future stream-flow. The Schwarze Elster shows little management influences on stream-flow both in the past and under future scenarios. WRM related to lignite mining activities rather than natural processes dominated seasonal and annual stream-flow variability of the Spree in the past, while reservoir management mainly impacted short-term variability. Long-term and short-term stream-flow variability of the Spree are expected to be further reduced in future by reservoir management and water transfers to ensure minimum flow requirements. Strong impacts ofWRM in reducing stream-flow variability in future scenarios underline the role of reservoir management as an effective and flexible adaptation option to uncertain climate change impacts on hydrology. KW - Water resources management KW - Reservoir management KW - Mining KW - Hydrological modelling KW - SWIM KW - WBalMo Y1 - 2019 UR - https://link.springer.com/article/10.1007%2Fs11269-019-02432-3 U6 - https://doi.org/10.1007/s11269-019-02432-3 SN - 1573-1650 SN - 0920-4741 VL - 33 IS - 15 SP - 5191 EP - 5206 ER -