National Repository of Grey Literature 14 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Methodology for rapid, comprehensive, independent decision-making on the need, effectiveness and interaction of adaptation measures in river basins under climate change
Fischer, Milan ; Zeman, Evžen ; Vizina, A. ; Hanel, M. ; Bernsteinová, Jana ; Tachecí, P. ; Štěpánek, Petr ; Pavlík, P. ; Máca, P. ; Ghisi, Tomáš ; Rapantová, N. ; Bláhová, Monika ; Janál, P. ; Trnka, Miroslav
The aim of the methodology is to present methods for quantifying the impacts of projected climate change on the water balance when applying adaptation measures in the Czech Republic for the next few decades. Adaptation measures should contribute to the sustainability of the water balance in all major user segments of water use and management in the basin. The main principle is the use of hydrological models to transform climate change scenarios into time series of hydrological conditions and to quantify the overall water balance of the basin using different types of adaptation measures and their implementation over time. Special emphasis is placed on the evaluation of combinations of adaptation measures that cannot be analysed by simplified methods. The methodology is designed to search for the optimal combination of adaptation measures in the assessed catchment. The proposed approach eliminates the shortcomings of effectiveness assessment from the perspective of the exclusive user of the water resource, as the evaluation of the effectiveness of adaptation measures is carried out in the form of a multi-criteria analysis of the evaluation of the outputs of the simulation model for predicting the water balance in the whole basin. This methodology can be used to assess different adaptation measures in all basic segments of water users: agriculture, forestry, energy, water management and others.
Methodology for determining the main disturbances in the water management balance and optimizing adaptation measures in the conditions climate change
Fischer, Milan ; Zeman, Evžen ; Vizina, A. ; Hanel, M. ; Bernsteinová, Jana ; Tachecí, P. ; Štěpánek, Petr ; Pavlík, P. ; Máca, P. ; Ghisi, Tomáš ; Rapantová, N. ; Bláhová, Monika ; Janál, P. ; Trnka, Miroslav
Ongoing climate change is causing a global increase in air temperature. While this is leading to an acceleration of the global hydrological cycle, and therefore a global increase in precipitation, the spatiotemporal variability in precipitation is much more complicated. While temperature in the Czech Republic shows a consistently increasing trend similar to that of surrounding countries and the planet as a whole, precipitation can be simplified that long-term averages of annual totals remain and are likely to remain very similar in the coming decades. Rising air temperatures inherently bring increased evaporative demand of the atmosphere and, for the same precipitation, a lower ratio of precipitation to evaporation, i.e. the climatic water balance shows a negative trend.
Risk assessment and prediction of natural fires in the immediate vicinity\nsurface sources of drinking water.
Trnka, Miroslav ; Kudláčková, Lucie ; Čermák, P. ; Balek, Jan ; Novotný, Jan ; Homolová, Lucie ; Semerádová, Daniela ; Brovkina, Olga ; Štěpánek, Petr ; Zahradníček, Pavel ; Skalák, Petr ; Bláhová, Monika ; Benáček, Patrik ; Fischer, Milan ; Sedlák, Pavel ; Janouš, Dalibor ; Žalud, Zdeněk ; Marek, Michal V. ; Možný, M. ; Hájková, L. ; Chuchma, F. ; Knozová, G. ; Beranová, J. ; Zatloukal, V. ; Albert, J. ; Mašková, R. ; Cienciala, E. ; Vizina, A. ; Nesládková, M. ; Melišová, E. ; Hanel, M.
The methodology formulates a procedure for assessing the risks of the occurrence and spread of natural fires in the immediate vicinity of surface sources of drinking water. The methodology\nproposes methods for estimating the consequences of natural fires on surface water quality, forecasting the change in the risk of fires due to climate change and the procedure for determining the risk of secondary pollution of reservoirs due to changes in run off after a natural fire. On this basis, the methodology proposes and diversifies preventíve and operational measures.The measures were designed in connection to modeling results for the Hadce pilot síte near the Švihov reservoir and the experience with the adverse effects of extensive deforestation on the water quality in the Vranov and Vír reservoirs.
Hydrological processes and dynamics in the changing climate and environment: Lessons learned from multiple temporal and spatial scales
Su, Ye ; Langhammer, Jakub (advisor) ; Hanel, Martin (referee) ; van Meerveld, Hilda (referee)
Hydrological processes and dynamics in the changing climate and environment: Lessons learned from multiple temporal and spatial scales Ye Su ABSTRACT Climate change, along with the changes in land use and land cover (LULC), is the key factor driving the changes in hydrological processes and dynamics in a basin. This thesis emphasized on understanding the impact of both long-term climate change and abrupt anthropogenic driven agricultural intensification or natural driven insect-induced forest disturbance on hydrological processes and dynamics at varying spatial and temporal scales in two diverting terrestrial environment. Two pattern-based investigations, one case study in a forest region in Central Europe and another in a semi-arid region in Central Asia, were aimed to answer the main research question "what are the responses of hydrological dynamics and the related hydro-geochemical conditions to climate change and certain changes in LULC at a basin-scale?". The long-term hydro-climatic dataset was used for conducting statistical analyses and establishing hydro-climatic modelling at the basin scale. We further conducted process-based studies, attempting to understand how and why the specific hydrological dynamics were altered at smaller spatial and temporal scales: (i) a catchment-scale tracer-based...
Hydrological drought in the context of climate change: Case study of the Blšanka and Loděnice basins
Burian, Alois ; Janský, Bohumír (advisor) ; Hanel, Martin (referee)
The final thesis deals with the issue of hydrological drought in the context of climate change. The basins of the Blšanka River and the Loděnice River have been suffering from water shortages in recent years, therefore they have been selected for the purposes of this final thesis. The thesis summarizes the basic principles used to estimate climate change on the water resources with emphasis on the occurrence of hydrological drought. At the same time, individual components and processes of hydrological modelling conditioning the formation of affected time series in the near (2020-2050) and far future (2070-2100) are described. A total of sixteen simulations created from the seven global climate models (GCM) of the CMIP5 project and three climate scenarios (RCP; Representative Concentration Pathways) are used. The time series of precipitation and air temperature, which have been influenced by the climate change, were derived by an advanced delta method that counts also with the change of variability. The conceptual hydrological model BILAN is used to simulate changes, due to its availability from the T. G. M. Research Institute of Water Management and its wide use in Czech conditions. The parameters of the BILAN model are calibrated based on the observed time series of both selected river basins....
Hydrological processes and dynamics in the changing climate and environment: Lessons learned from multiple temporal and spatial scales
Su, Ye ; Langhammer, Jakub (advisor) ; Hanel, Martin (referee) ; van Meerveld, Hilda (referee)
Hydrological processes and dynamics in the changing climate and environment: Lessons learned from multiple temporal and spatial scales Ye Su ABSTRACT Climate change, along with the changes in land use and land cover (LULC), is the key factor driving the changes in hydrological processes and dynamics in a basin. This thesis emphasized on understanding the impact of both long-term climate change and abrupt anthropogenic driven agricultural intensification or natural driven insect-induced forest disturbance on hydrological processes and dynamics at varying spatial and temporal scales in two diverting terrestrial environment. Two pattern-based investigations, one case study in a forest region in Central Europe and another in a semi-arid region in Central Asia, were aimed to answer the main research question "what are the responses of hydrological dynamics and the related hydro-geochemical conditions to climate change and certain changes in LULC at a basin-scale?". The long-term hydro-climatic dataset was used for conducting statistical analyses and establishing hydro-climatic modelling at the basin scale. We further conducted process-based studies, attempting to understand how and why the specific hydrological dynamics were altered at smaller spatial and temporal scales: (i) a catchment-scale tracer-based...
Balancing Assessment of Available Water Resources and Moisture Needs within Defined "Irrigation Districts”
Trnka, Miroslav ; Hlavinka, Petr ; Balek, Jan ; Semerádová, Daniela ; Dubrovský, Martin ; Štěpánek, Petr ; Vizina, A. ; Hanel, M. ; Žalud, Z. ; Lukas, V. ; Dumbrovský, M. ; Růžek, P. ; Daňhelka, J. ; Chuchma, F. ; Novák, P. ; Novotný, I. ; Pavlík, F.
This report is processing research results done within the contractual cooperation of the Institute of Global Change Research (as a research provider) and Státní pozemkový úřad - the Czech National Land Authority (demander), which was prepared in collaboration with other research partners. The report deals with balancing assessment of available water resources and moisture needs within defined "irrigation districts” of the Czech Republic with regard to the ongoing climate change
Application of optimization methods in hydrological modeling
Jakubcová, Michala ; Máca, Petr (advisor) ; Hanel, Martin (referee)
Finding the optimal state of reality is the main purpose of the optimization process. The best variant from many possibilities is selected, and the effectiveness of the given system increases. Optimization has been applied in many real life engineering problems as in hydrological modelling. Within the hydrological case studies, the optimization process serves to estimate the best set of model parameters, or to train model weights in artificial neural networks. Particle swarm optimization (PSO) is relatively recent optimization technique, which has only a few parameters to adjust, and is easy to implement to the selected problem. The original algorithm was modified by many authors. They focused on changing the initialization of particles in the swarm, updating the population topology, adding new parameters into the equation, or incorporating shuffling mechanism into the algorithm. The modifications of PSO algorithm improve the performance of the optimization, prevent the premature convergence, and decrease computation time. Therefore, the main aims of the presented doctoral thesis consist of proposal of a new PSO modification with its implementation in C++ programming language. More PSO variants were compared and analysed, and the best methods based on benchmark problems were applied in two hydrological case studies. The first case study focused on utilization of PSO algorithms in inverse problem related to estimation of parameters of rainfall-runoff model Bilan. In the second case study, combination of artificial neural networks with PSO methods was introduced for forecasting the Standardized precipitation evapotranspiration drought index. It was found out, that particle swarm optimization is a suitable tool for solving problems in hydrological modelling. The most effective PSO modifications are the one with adaptive version of parameter of inertia weight, which updates the velocity of particles during searching through the multidimensional space via feedback information. The shuffling mechanism and redistribution of particles into complexes, at which the PSO runs separately, also significantly improve the performance. The contribution of this doctoral thesis lies in creation of new PSO modification, which was tested on benchmark problems, and was successfully applied in two hydrological case studies. The results of this thesis also extended the utilization of PSO methods in real life engineering optimization problems. All analysed PSO algorithms are available for later use within other research projects.
Using Weather Generators for the Assessment of the Impact of Climate Change in Catchments
Martínková, Marta ; Hanel, Martin (advisor) ; Máca, Petr (referee)
The main objective of this dissertation is to provide a novel approach to downscaling of outputs from regional climate models and to simulation of future climate. The resulting method consists of rain generator that operates in 6-hour time step. The generator performs well for the observational data. It consists of following steps: disaggregation of 6-hour cumulative precipitation into convective and stratiform types, fitting of first order 3-state discrete time Markov chain to the data and simulation of long time series of precipitation. Then the mixture of log-normal and Generalized Pareto distribution is fitted to stratiform events and the Generalized extreme value distribution is fitted to convective events. The impact of climate change on precipitation is evaluated by using change factors that are identified for precipitation occurrence (by comparing the transition matrices for the future and control period) and for precipitation amount (by comparing the scale and location parameters of distributions fitted for the future and control period). The observational data are then altered with obtained change factors. From evaluation of observational data it stems that the average volume of an convective event is higher for the western region than for eastern region of the Czech Republic. Additionally, statistically significant trends in number and volume of convective events were identified for the region. The relative portion of convective precipitation is the highest in summer for observational data. From analysis of RCMs simulations, it stems that even though the overall precipitation is projected to be lower in future, the proportion of convective events (versus stratiform ones) would be higher. The number of convective events is projected to be lower in the future, while the volume of a convective event to be bigger.
The assessment of change in the water balance of Hačka catchment due to the climate change
Moravec, Vojtěch ; Hanel, Martin (advisor) ; Ladislav, Ladislav (referee)
In the presented paper the changes in mean runoff, temperature and precipitation totals in an observed period 1962-2015 in the catchment river Hačka are assessed. The paper further presents the analysis of climate change impact on mean runoff between the periods 1984-2014 (control period) and 2035-2065 and 2068-2098 (scenario periods) using the projections of three regional climate model simulations. Thin Plate Spline interpolation was used to estimate basin precipitation and temperature. Modified hydrological analogy was used for precise quantification of naturalized runoff (i.e. not affected by water use). Climate change scenarios were derived using simple delta change approach, i.e. observed series of precipitation and temperature were adjusted in order to give the same changes between the control and scenario period as regional climate model simulations. Hydrological balance was modelled with a conceptual hydrological model Bilan. The parameters of the hydrological model were estimated using observed data. These parameters were subsequently used to derive discharge series under climate change conditions for each regional climate model simulation. Results showed a 1.7 °C average increase in mean annual temperature in the scenario period 2035-2065 and a 2.8 °C average increase in the scenario period 2068-2098. The seasonal cycle of precipitation in the scenario conditions is shifted, although mean annual precipitation totals remain practically unchanged (max changes -8.1 %; +9.3 %). The mean annual discharge decreases by 5.7% in average (most 20.3 %) in period 2035-2065 and a significant decrease of 25.5% in average (most 45.9 %) in annual mean discharge is expected in the period 2068-2098. Frequency of minimal runoff is expected to increase up to two times. Precipitation increase is expected from the beginning of the fall to the beginning of the summer, with a slight decrease in spring. Increase in precipitation is followed by evapotranspiration increase, caused by increase in temperature. Summer precipitation is expected to decrease as well as summer runoff. Due to the temperature increase, time shift of the snowmelt is expected from the periods between March-April to January-February. This will also affect the increase of the discharge in this period. This knowledge can be applied in water management planning in the future.

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