TY - JOUR A1 - Didovets, Iulii A1 - Krysanova, Valentina A1 - Bürger, Gerd A1 - Snizhko, Sergiy A1 - Balabukh, Vira A1 - Bronstert, Axel T1 - Climate change impact on regional floods in the Carpathian region JF - Journal of hydrology : Regional studies N2 - Study region: Tisza and Prut catchments, originating on the slopes of the Carpathian mountains. Study focus: The study reported here investigates (i) climate change impacts on flood risk in the region, and (ii) uncertainty related to hydrological modelling, downscaling techniques and climate projections. The climate projections used in the study were derived from five GCMs, downscaled either dynamically with RCMs or with the statistical downscaling model XDS. The resulting climate change scenarios were applied to drive the eco-hydrological model SWIM, which was calibrated and validated for the catchments in advance using observed climate and hydrological data. The changes in the 30-year flood hazards and 98 and 95 percentiles of discharge were evaluated for the far future period (2071-2100) in comparison with the reference period (1981-2010). New hydrological insights for the region: The majority of model outputs under RCP 4.5 show a small to strong increase of the 30-year flood level in the Tisza ranging from 4.5% to 62%, and moderate increase in the Prut ranging from 11% to 22%. The impact results under RCP 8.5 are more uncertain with changes in both directions due to high uncertainties in GCM-RCM climate projections, downscaling methods and the low density of available climate stations. KW - Climate change impact KW - Floods KW - Hydrological modelling KW - SWIM KW - Tisza KW - Prut KW - Carpathians KW - Ukraine Y1 - 2019 U6 - https://doi.org/10.1016/j.ejrh.2019.01.002 SN - 2214-5818 VL - 22 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huang, Shaochun A1 - Hattermann, Fred Fokko A1 - Krysanova, Valentina A1 - Bronstert, Axel T1 - Projections of climate change impacts on river flood conditions in Germany by combining three different RCMs with a regional eco-hydrological model JF - Climatic change : an interdisciplinary, intern. journal devoted to the description, causes and implications of climatic change N2 - A general increase in precipitation has been observed in Germany in the last century, and potential changes in flood generation and intensity are now at the focus of interest. The aim of the paper is twofold: a) to project the future flood conditions in Germany accounting for various river regimes (from pluvial to nival-pluvial regimes) and under different climate scenarios (the high, A2, low, B1, and medium, A1B, emission scenarios) and b) to investigate sources of uncertainty generated by climate input data and regional climate models. Data of two dynamical Regional Climate Models (RCMs), REMO (REgional Model) and CCLM (Cosmo-Climate Local Model), and one statistical-empirical RCM, Wettreg (Wetterlagenbasierte Regionalisierungsmethode: weather-type based regionalization method), were applied to drive the eco-hydrological model SWIM (Soil and Water Integrated Model), which was previously validated for 15 gauges in Germany. At most of the gauges, the 95 and 99 percentiles of the simulated discharge using SWIM with observed climate data had a good agreement with the observed discharge for 1961-2000 (deviation within +/- 10 %). However, the simulated discharge had a bias when using RCM climate as input for the same period. Generalized Extreme Value (GEV) distributions were fitted to the annual maximum series of river runoff for each realization for the control and scenario periods, and the changes in flood generation over the whole simulation time were analyzed. The 50-year flood values estimated for two scenario periods (2021-2060, 2061-2100) were compared to the ones derived from the control period using the same climate models. The results driven by the statistical-empirical model show a declining trend in the flood level for most rivers, and under all climate scenarios. The simulations driven by dynamical models give various change directions depending on region, scenario and time period. The uncertainty in estimating high flows and, in particular, extreme floods remains high, due to differences in regional climate models, emission scenarios and multi-realizations generated by RCMs. Y1 - 2013 U6 - https://doi.org/10.1007/s10584-012-0586-2 SN - 0165-0009 SN - 1573-1480 VL - 116 IS - 3-4 SP - 631 EP - 663 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Hesse, Cornelia A1 - Krysanova, Valentina A1 - Vetter, Tobias A1 - Reinhardt, Julia T1 - Comparison of several approaches representing terrestrial and in-stream nutrient retention and decomposition in watershed modelling JF - Ecological modelling : international journal on ecological modelling and engineering and systems ecolog N2 - Retention and transformation of nutrients within a river catchment are important mechanisms influencing water quality measured at the watershed outlet. Nutrient storage and reduction can occur in soils as well as in the river and should be considered in water quality modelling. Consideration is possible using various methods at several points during modelling cascade. The study compares the effects of five different equation sets implemented into the Soil and Water Integrated Model (SWIM), one describing terrestrial and four in-stream retention with a rising complexity (including algal growth and death at the highest complexity level). The influences of the different methods alone and in combinations on water quality model outputs (NO3-N, NH4-N, PO4-P) were analyzed for the outlet of the large-scale Saale basin in Germany. Experiments revealed that nutrient forms coming primarily from diffuse sources are mostly influenced by retention processes in the soils of the catchment, and river processes are less important. Nutrients introduced to the river mainly by point sources are more subject to retention by in-stream processes, but both nutrient retention and transformation processes in soils and rivers have to be included. Although the best overall results could be achieved at the highest complexity level, the calibration efforts for this case are extremely high, and only minor improvements of overall model performance with the highest complexity were detected. Therefore, it could be reasoned that for some research questions also less complex model approaches would be sufficient, which could help to reduce unnecessary complexity and diminish high uncertainty in water quality modelling at the catchment scale. (C) 2013 Elsevier B.V. All rights reserved. KW - Water quality modelling KW - Nutrients KW - Retention KW - River basin KW - Model complexity KW - SWIM Y1 - 2013 U6 - https://doi.org/10.1016/j.ecolmodel.2013.08.017 SN - 0304-3800 SN - 1872-7026 VL - 269 IS - 34 SP - 70 EP - 85 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Aich, Valentin A1 - Liersch, Stefan A1 - Vetter, T. A1 - Huang, S. A1 - Tecklenburg, J. A1 - Hoffmann, P. A1 - Koch, H. A1 - Fournet, S. A1 - Krysanova, Valentina A1 - Mueller, N. A1 - Hattermann, Fred Fokko T1 - Comparing impacts of climate change on streamflow in four large African river basins JF - Hydrology and earth system sciences : HESS N2 - This study aims to compare impacts of climate change on streamflow in four large representative African river basins: the Niger, the Upper Blue Nile, the Oubangui and the Limpopo. We set up the eco-hydrological model SWIM (Soil and Water Integrated Model) for all four basins individually. The validation of the models for four basins shows results from adequate to very good, depending on the quality and availability of input and calibration data. For the climate impact assessment, we drive the model with outputs of five bias corrected Earth system models of Coupled Model Intercomparison Project Phase 5 (CMIP5) for the representative concentration pathways (RCPs) 2.6 and 8.5. This climate input is put into the context of climate trends of the whole African continent and compared to a CMIP5 ensemble of 19 models in order to test their representativeness. Subsequently, we compare the trends in mean discharges, seasonality and hydrological extremes in the 21st century. The uncertainty of results for all basins is high. Still, climate change impact is clearly visible for mean discharges but also for extremes in high and low flows. The uncertainty of the projections is the lowest in the Upper Blue Nile, where an increase in streamflow is most likely. In the Niger and the Limpopo basins, the magnitude of trends in both directions is high and has a wide range of uncertainty. In the Oubangui, impacts are the least significant. Our results confirm partly the findings of previous continental impact analyses for Africa. However, contradictory to these studies we find a tendency for increased streamflows in three of the four basins (not for the Oubangui). Guided by these results, we argue for attention to the possible risks of increasing high flows in the face of the dominant water scarcity in Africa. In conclusion, the study shows that impact intercomparisons have added value to the adaptation discussion and may be used for setting up adaptation plans in the context of a holistic approach. Y1 - 2014 U6 - https://doi.org/10.5194/hess-18-1305-2014 SN - 1027-5606 SN - 1607-7938 VL - 18 IS - 4 SP - 1305 EP - 1321 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Hattermann, Fred Fokko A1 - Krysanova, Valentina A1 - Habeck, Anja A1 - Bronstert, Axel T1 - Integrating wetlands and riparian zones in river basin modelling JF - Ecological modelling : international journal on ecological modelling and engineering and systems ecolog N2 - Wetlands, and in particular riparian wetlands, represent an interface between the catchment area and the aquatic environment. They control the exchange of water and related chemical fluxes from the upper catchment area to surface waters like streams and lakes. Their influence on water and nutrient balances has been investigated mainly at the patch scale. In this study an attempt was made (a) to integrate riparian zones and wetlands into eco-hydrological river basin modelling, and (b) to quantify the impacts of riparian wetland processes on water and nutrient fluxes in a meso-scale catchment located in the northeastern German lowland. The investigation was performed by analysing hydro-chemical field data and applying the eco-hydrological model SWIM (Soil and Water Integrated Model), which was extended to reproduce the relevant water and nutrient flows and retention processes at the catchment scale in general, and in riparian zones and wetlands in particular. The main extensions introduced in the model were: (1) implementation of daily groundwater table dynamics at the hydrotope level, (2) implementation of water and nutrient uptake by plants from groundwater in riparian zones and wetlands, and (3) assessment of nutrient retention in groundwater and interflow. The simulation results indicate that wetlands, though they represent relatively small parts of the total catchment area, may have a significant impact on the overall water and nutrient balances of the catchment. The uncertainty of the simulation results is considerably high, with the main sources of uncertainty being the model parameters representing the geo-hydrology and the input data for land use management. (c) 2006 Elsevier B.V. All rights reserved. KW - riparian zones KW - wetlands KW - water quality KW - groundwater dynamics KW - nutrient retention KW - integrated river basin modelling Y1 - 2006 U6 - https://doi.org/10.1016/j.ecolmodel.2005.06.012 SN - 0304-3800 VL - 199 IS - 4 SP - 379 EP - 392 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Didovets, Iulii A1 - Lobanova, Anastasia A1 - Bronstert, Axel A1 - Snizhko, Sergiy A1 - Maule, Cathrine Fox A1 - Krysanova, Valentina T1 - Assessment of Climate Change Impacts on Water Resources in Three Representative Ukrainian Catchments Using Eco-Hydrological Modelling JF - Water N2 - The information about climate change impact on river discharge is vitally important for planning adaptation measures. The future changes can affect different water-related sectors. The main goal of this study was to investigate the potential water resource changes in Ukraine, focusing on three mesoscale river catchments (Teteriv, UpperWestern Bug, and Samara) characteristic for different geographical zones. The catchment scale watershed model—Soil and Water Integrated Model (SWIM)—was setup, calibrated, and validated for the three catchments under consideration. A set of seven GCM-RCM (General Circulation Model-Regional Climate Model) coupled climate scenarios corresponding to RCPs (Representative Concentration Pathways) 4.5 and 8.5 were used to drive the hydrological catchment model. The climate projections, used in the study, were considered as three combinations of low, intermediate, and high end scenarios. Our results indicate the shifts in the seasonal distribution of runoff in all three catchments. The spring high flow occurs earlier as a result of temperature increases and earlier snowmelt. The fairly robust trend is an increase in river discharge in the winter season, and most of the scenarios show a potential decrease in river discharge in the spring. KW - Ukraine KW - climate change impact KW - river discharge KW - Samara KW - Teteriv KW - Western Bug KW - runoff KW - SWIM KW - IMPRESSIONS Y1 - 2017 U6 - https://doi.org/10.3390/w9030204 SN - 2073-4441 VL - 9 IS - 3 PB - MDPI CY - Basel ER - TY - GEN A1 - Didovets, Iulii A1 - Lobanova, Anastasia A1 - Bronstert, Axel A1 - Snizhko, Sergiy A1 - Maule, Cathrine Fox A1 - Krysanova, Valentina T1 - Assessment of Climate Change Impacts on Water Resources in Three Representative Ukrainian Catchments Using Eco-Hydrological Modelling N2 - The information about climate change impact on river discharge is vitally important for planning adaptation measures. The future changes can affect different water-related sectors. The main goal of this study was to investigate the potential water resource changes in Ukraine, focusing on three mesoscale river catchments (Teteriv, UpperWestern Bug, and Samara) characteristic for different geographical zones. The catchment scale watershed model—Soil and Water Integrated Model (SWIM)—was setup, calibrated, and validated for the three catchments under consideration. A set of seven GCM-RCM (General Circulation Model-Regional Climate Model) coupled climate scenarios corresponding to RCPs (Representative Concentration Pathways) 4.5 and 8.5 were used to drive the hydrological catchment model. The climate projections, used in the study, were considered as three combinations of low, intermediate, and high end scenarios. Our results indicate the shifts in the seasonal distribution of runoff in all three catchments. The spring high flow occurs earlier as a result of temperature increases and earlier snowmelt. The fairly robust trend is an increase in river discharge in the winter season, and most of the scenarios show a potential decrease in river discharge in the spring. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 323 KW - Ukraine KW - climate change impact KW - river discharge KW - Samara KW - Teteriv KW - Western Bug KW - runoff KW - SWIM KW - IMPRESSIONS Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-394956 ER - TY - JOUR A1 - Menzel, Lucas A1 - Bronstert, Axel A1 - Bürger, Gerd A1 - Krysanova, Valentina T1 - Environmental change scenarios and flood responses in the Elbe catchment (Germany) Y1 - 2000 ER - TY - JOUR A1 - Fernandez-Palomino, Carlos Antonio A1 - Hattermann, Fred F. A1 - Krysanova, Valentina A1 - Vega-Jacome, Fiorella A1 - Bronstert, Axel T1 - Towards a more consistent eco-hydrological modelling through multi-objective calibration BT - a case study in the Andean Vilcanota River basin, Perú JF - Hydrological sciences journal = Journal des sciences hydrologiques N2 - Most hydrological studies rely on a model calibrated using discharge alone. However, judging the model reliability based on such calibration is problematic, as it does not guarantee the correct representation of internal hydrological processes. This study aims (a) to develop a comprehensive multi-objective calibration framework using remote sensing vegetation data and hydrological signatures (flow duration curve - FDC, and baseflow index) in addition to discharge, and (b) to apply this framework for calibration of the Soil and Water Assessment Tool (SWAT) in a typical Andean catchment. Overall, our calibration approach outperformed traditional discharge-based and FDC signature-based calibration strategies in terms of vegetation, streamflow, and flow partitioning simulation. New hydrological insights for the region are the following: baseflow is the main component of the streamflow sustaining the long dry-season flow, and pasture areas offer higher water yield and baseflow than other land-cover types. The proposed approach could be used in other data-scarce regions with complex topography. KW - Andes KW - eco-hydrology KW - SWAT KW - hydrological signatures KW - remote sensing KW - equifinality Y1 - 2020 U6 - https://doi.org/10.1080/02626667.2020.1846740 SN - 0262-6667 SN - 2150-3435 VL - 66 IS - 1 SP - 59 EP - 74 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - GEN A1 - Fernandez-Palomino, Carlos Antonio A1 - Hattermann, Fred F. A1 - Krysanova, Valentina A1 - Vega-Jacome, Fiorella A1 - Bronstert, Axel T1 - Towards a more consistent eco-hydrological modelling through multi-objective calibration BT - a case study in the Andean Vilcanota River basin, Perú T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Most hydrological studies rely on a model calibrated using discharge alone. However, judging the model reliability based on such calibration is problematic, as it does not guarantee the correct representation of internal hydrological processes. This study aims (a) to develop a comprehensive multi-objective calibration framework using remote sensing vegetation data and hydrological signatures (flow duration curve - FDC, and baseflow index) in addition to discharge, and (b) to apply this framework for calibration of the Soil and Water Assessment Tool (SWAT) in a typical Andean catchment. Overall, our calibration approach outperformed traditional discharge-based and FDC signature-based calibration strategies in terms of vegetation, streamflow, and flow partitioning simulation. New hydrological insights for the region are the following: baseflow is the main component of the streamflow sustaining the long dry-season flow, and pasture areas offer higher water yield and baseflow than other land-cover types. The proposed approach could be used in other data-scarce regions with complex topography. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1377 KW - Andes KW - eco-hydrology KW - SWAT KW - hydrological signatures KW - remote sensing KW - equifinality Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-568766 SN - 1866-8372 IS - 1 ER -