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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
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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Frequency and trend analysis of rain-on-snow events at selected meteorological stations in the Czech Rebublic
Kakalejčík, Matej ; Jeníček, Michal (advisor) ; Blahušiaková, Andrea (referee)
Rain-on-snow events represent a natural hydro-meteorological phenomenon and their occurrence is often associated with floods. Due to the climate change occurrence, rain-on snow events are also changing. The main goal of diploma thesis is to define spatial and temporal occurrence of rain-on-snow events at 16 selected meteorological stations in the Czech Republic between the years 1966-2012. Spatial occurrence of rain-on-snow events is expressed by number of events per meteorological station. Final number of events varies widely even between the stations with similar altitude. Stations with the highest frequency of rain-on-snow events are located in Jizerské hory between 675 and 780 m a.s.l. Temporal occurrence of rain- on-snow events is expressed by number of events per year and month respectively. Time series of rain-on-snow events were analysed by statistical trends to gain information about changes in occurrence over time. Most of the stations proved no statistically significant trend. There was a trend detected only at four out of 16 stations. Three meteorological stations showed a rising trend, whereas one station signalled a decreasing trend. More complex results were produced by the trend analysis of monthly time series of rain-on snow events. Nine stations yielded at least one month with a...
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Extreme hydrological events in the Rolava River basin
Vlach, Vojtěch ; Matoušková, Milada (advisor) ; Blahušiaková, Andrea (referee)
6 Abstract This bachelor thesis deals with characteristics of extreme hydrological events in the Rolava river basin, which is located in the Ore Mountains in northwestern part of Czech Republic. The main aim of this study is a comparison of hydrological extremes in headwater catchments of Rolava River and Slatinný brook using data from the experimental monitoring of Department of Physical Geography and Geoecology, Faculty of Science, Charles University in Prague and Czech Hydrometeorological Institute. The other object is a field survey of the impacts of hydrological extremes on fluvial-morphological dynamics of the streams, focused on river-bed forming processes. The opening part of this thesis deals with the physical geographical and hydrographical characteristics. The main part is devoted to the comparison of extreme events in the monitored catchments focusing on floods and drought. As a final result, it was found out that Slatinný brook has a greater tendency to extremity of peak discharges. Another part of the results is an analysis of the five-year flood seasonality change on upper course of the Rolava River in two periods 1967-1990 and 1991-2014. Key words: extreme events, flood, drought, fluvial dynamics, Rolava, Slatinný brook
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