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Impact of the regional climate change on the hydrological regime with regard to extremes
Blahušiaková, Andrea
Investigation of changes in the rainfall-runoff regimes of rivers and its extremes has become more important especially in the context of ongoing and future climate changes. The main aim of this study is to investigate the key factors involved in these changes and thus influence the hydrological regime. Trends and changes in climatic and hydrological variables are detected and the development of flood and drought extremes is assessed. Several methods are used to identify trends and examine their changes; the Mann-Kendall test, linear regression, simple mass curves, and comparative analysis (IHA). Flood extremity is evaluated based on flood activity levels and return period (N-year flood event), frequency and seasonality using the threshold method and culmination day. Extremity, frequency and seasonality of meteorological drought are evaluated by the threshold method, followed by de Martonne Aridity index and Relative precipitation index. Hydrological drought is evaluated based on Base flow index, Low flow index and threshold method. The main variables involved in these analyzes were annual, seasonal and monthly discharge, air temperature, precipitation and snow cover. The database of the base and other calculated variables is compiled for the period from 1931/1961 to 2010/2012. Trends and changes...
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Impact of the regional climate change on the hydrological regime with regard to extremes
Blahušiaková, Andrea ; Matoušková, Milada (advisor) ; Kašpárek, Ladislav (referee) ; Pekárová, Pavla (referee)
Investigation of changes in the rainfall-runoff regimes of rivers and its extremes has become more important especially in the context of ongoing and future climate changes. The main aim of this study is to investigate the key factors involved in these changes and thus influence the hydrological regime. Trends and changes in climatic and hydrological variables are detected and the development of flood and drought extremes is assessed. Several methods are used to identify trends and examine their changes; the Mann-Kendall test, linear regression, simple mass curves, and comparative analysis (IHA). Flood extremity is evaluated based on flood activity levels and return period (N-year flood event), frequency and seasonality using the threshold method and culmination day. Extremity, frequency and seasonality of meteorological drought are evaluated by the threshold method, followed by de Martonne Aridity index and Relative precipitation index. Hydrological drought is evaluated based on Base flow index, Low flow index and threshold method. The main variables involved in these analyzes were annual, seasonal and monthly discharge, air temperature, precipitation and snow cover. The database of the base and other calculated variables is compiled for the period from 1931/1961 to 2010/2012. Trends and changes...
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Hydrological drought in headwater areas of the Ore Mountains
Vlach, Vojtěch ; Matoušková, Milada (advisor) ; Kliment, Zdeněk (referee)
Changes in the hydrological cycle are one of the expected impacts of climate change. Until recently, Central European mountain ranges have not been considered to be affected by water scarcity. Nevertheless, recent years have suggested an increasing risk of drought occurrence also in these regions, which have a major impact on the water supply to rivers that drain them. The master thesis deals with the evaluation of hydrological drought in the headwater areas of three catchments in the Ore Mountains for the period from 1967 to 2018. The main aim is to compare the of hydrological drought characteristics in the catchment areas of upper Svatava River, upper Rolava River and Načetínský brook based on available hydrological and climatic data. In connection with this, the work aims to detect the long-term trends of drought occurrence in selected basins. Furthermore, the emphasis is given on the evaluation of natural conditions, especially the historical and current land cover changes in the study catchments. The results point to a significant change in the seasonality of the occurrence of hydrological drought in the second half of the studied period, when the streamflow deficits concentrate between August and October. Furthermore, increasing trends in deficit volumes were found in the catchment areas of...
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Analysis of rainfall-runoff regime in the catchment of the Slatinny brook (Krušné hory).
Buková, Eva ; Matoušková, Milada (advisor) ; Šobr, Miroslav (referee)
Analysis of rainfall-runoff regime in the catchment of the Slatinny brook (Krušné hory) ABSTRACT Bachelor thesis deals with the characteristics of runoff regime Slatinny brook, which is located in the northwest of the Czech Republic in the Ore Mountains. Part of this study is dedicated to general physical and geographical characteristics, which also includes hydrographic basin features. The main objective of this study was to process and analyze the hydrological data obtained from experimental monitoring carried out by the Department of Physical Geography and Geoecology, Faculty of Science, Charles University in Prague. The data were firstly homogenized and than complemented with the missing values. Discharges have been derived from the modified data of water levels using the consumptive curve. For the analysis of rainfall-runoff regime were used basic statistical methods used in hydrology. The thesis also includes analysis of selected extreme runoff situations of the Slatinny brook. Key words: rainfall-runoff regime, outflow variability, discharge, Slatinny brook
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Rainfall-runoff regime in the headwater part of the Bystřice River basin
Šedivá, Kateřina ; Jeníček, Michal (advisor) ; Hladíková, Alice (referee)
Rainfall-runoff regime in the headwater part of the Bystřice River Abstract This bachelor thesis deals with the rainfall-runoff regime and analysis of extreme situations in the headwater part of the Bystřice River basin. At first, the area of interest is described in physical and geographical terms and the influences of individual factors on the runoff are mentioned. The text content is documented by maps. The characteristic of rainfall-runoff regime is evaluated by means of runoff variability parameters. The variability is assessed by means of collected data using charts illustrating exceedance probability of average daily discharges in years 2009 and 2010. The flow variations are evaluated on the basis of decile deviations. The distribution of monthly discharges in the Bystřice River is displayed and the monthly flow variability is described in pie graphs separately for hydrological years 2009 and 2010. The monthly balance of the runoff is also evaluated by means of statistical measures of Kr and Cv coefficients. Finally, the runoff regime evaluation is completed with exceedance probability calculation of the mean annual discharge. The assessment of selected extreme events forms an important part of the thesis. Extreme situations are compared with synoptic situations; it contributes to explain causal...
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Snow regime characteristic of the Zlatý Brook in the Krušné Mountains in years 2009-2011
Hájková, Barbora ; Jeníček, Michal (advisor) ; Kučerová, Dana (referee)
This bachelor thesis is focused on the snow regime characteristic of Zlatý Brook in the Krušné Mountains. Both processes connected with snowmelt runoff and processes anticipating the runoff are described in this work. Data obtained in the catchment during the field measurements in winter periods 2008/2009, 2009/2010 and 2010/2011are described and analyzed. Measured point data are completed with information available from gauged measurements. Special attention is paid mainly to the snow depth, snow water equivalent and their spatial distribution in the catchment. Key words: snow regime, snowpack, snow water equivalent, snowmelt runoff, Zlatý brook, Krušné Mountains
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Changes of rainfall-runoff regime in the Stropnice river-basin
Volková, Alena ; Janský, Bohumír (referee) ; Šobr, Miroslav (advisor)
This paper deals with the rainfall-runoff regime in the Stropnice river-basin and its development. The aim of this paper is to answer the question of‚were there any changes in the runoff regime during the period 1945 - 2009, and if so, were these changes conditioned by climate or were they caused by human interventions' (e. g. river network modification, changes of the land cover, drainage systems development etc.). The single-mass and double- mass curves were used as the primary methodology. The homogeneity of the time series of mean discharge, precipitation and air temperature were statistically tested using Mann-Whitney-Pettit test and Mann-Whitney test. The Mann-Whitney-Pettit test was performed using the programme AnClim (v5.012), which is freely available online, the Mann-Whitney test was performed using SPSS 15.0. Non-parametric Mann-Kendall test was used for the trend detection, performed in MULTMK/PARTMK by C. Libiseller and A. Grimvall, also freely available online. Some changes in the runoff regime were uncovered in the early 80s', when the runoff decreased, which also happened after 1988. During these periods almost no annual flood occured. The first decrease of the runoff was caused by a drier season in the 80s'. The second decrease after 1988 was probably caused by a build-up of the...
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