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The relationships between atmospheric circulation and surface climatic elements in Europe
Pokorná, Lucie ; Huth, Radan (advisor) ; Kalvová, Jaroslava (referee) ; Kliegrová, Stanislava (referee)
The relationships between atmospheric circulation and surface climatic elements in Europe Lucie Pokorná Abstract The variability of atmospheric circulation is the most important factor determining the changes in surface climatic elements. In this work, the relationship between atmospheric circulation and surface climatic elements like the temperature and the precipitation amounts and occurrence over the European region and some other climatic elements in central Europe is focused. The atmospheric circulation during the year is represented by modes of low-frequency circulation variability in sea level pressure (SLP) and 500-hPa heights (Z500) obtained by using statistical method "Principal component analysis". The Pearson correlation coefficient is used to describe the relationship between modes and climatic elements. Four circulation patterns in Z500 over Euro-Atlantic sector influence climate in Europe all over the year: the North Atlantic Oscillation (NAO) pattern, the East Atlantic (EA) pattern, and two Eurasian patterns (EU1, EU2). There were found patterns in SLP that strongly correlate with modes of the Z500 and influence surface climate similar way. Statistically important correlations of modes in Z500 and SLP with maximum, minimum and mean temperature, precipitation amounts and occurrence of...
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Short-term precipitation amounts
Dragula, Adam ; Holtanová, Eva (advisor) ; Kliegrová, Stanislava (referee)
Title: Short-term precipitation amounts Author: Adam Dragula Department: Department of Atmospheric Physics Supervisor: RNDr. Eva Holtanová, Ph.D., Department of Atmospheric Physics Abstract: The main object of this thesis is an analysis of short-term precipitation amounts with emphasis on transition period between pluviometer and automatic rain gauge. For the analysis, we were given data by Czech hydrometeorological institute, which contain precipitation amounts measured by pluviometer of 10 minutes term and precipitation amounts measured by automatic rain gauges of 10 and 15 minutes terms for four climatic stations. A summary of basic knowledge of measurement of precipitation and methodology of detection of inhomogenities in climatic time series is the point of the first part of the thesis. The aim of data analysis is to analyze basic characteristics of statistical distribution of precipitation amounts on a scale of days, hours and finally 10 or 15 minutes terms . A comparison of the distribution is carried out firstly in the transition period, where measurements of pluviometer and automatic rain gauge have an overlap, then two separate periods before and after automation are being compared. The main outcome of the thesis is a description of a possible cause of an inhomogenity caused by a change of...
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Short-term precipitation amounts
Dragula, Adam ; Holtanová, Eva (advisor) ; Kliegrová, Stanislava (referee)
Title: Short-term precipitation amounts Author: Adam Dragula Department: Department of Atmospheric Physics Supervisor: RNDr. Eva Holtanová, Ph.D., Department of Atmospheric Physics Abstract: The main object of this thesis is an analysis of short-term precipitation amounts with emphasis on transition period between pluviometer and automatic rain gauge. For the analysis, we were given data by Czech hydrometeorological institute, which contain precipitation amounts measured by pluviometer of 10 minutes term and precipitation amounts measured by automatic rain gauges of 10 and 15 minutes terms for four climatic stations. A summary of basic knowledge of measurement of precipitation and methodology of detection of inhomogenities in climatic time series is the point of the first part of the thesis. The aim of data analysis is to analyze basic characteristics of statistical distribution of precipitation amounts on a scale of days, hours and finally 10 or 15 minutes terms . A comparison of the distribution is carried out firstly in the transition period, where measurements of pluviometer and automatic rain gauge have an overlap, then two separate periods before and after automation are being compared. The main outcome of the thesis is a description of a possible cause of an inhomogenity caused by a change of...
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Continentality of climate over Europe
Hudek, Jakub ; Holtanová, Eva (advisor) ; Kliegrová, Stanislava (referee)
In present work the continentality of climate over Europe is studied. Attention is given to its basic characteristics, geographic distribution and its dependences on latitude and longitude. Firstly basic terms such as annual air temperature amplitude, thermal continentality and corresponding indices that characterize it are described. Attention is paid to the geographic distribution of continental indices for two reference periods (1951 - 1980 and 1981 - 2010) and the differences between them. The dependences of individual indices on latitude and longitude in order to capture in greater detail their properties are also studied. The results have shown that there has been considerable change of continentality between these periods in most of Europe's territory, which is described in detail in this work.
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Assessment of regional climate models performance in simulating present-day climate over the area of the Czech Republic
Crhová, Lenka ; Kalvová, Jaroslava (advisor) ; Kliegrová, Stanislava (referee)
Title: Assessment of regional climate models performance in simulating present-day climate over the area of the Czech Republic Author: Lenka Crhová Department: Department of Meteorology and Environment Protection Supervisor:doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: Jaroslava.Kalvova@mff.cuni.cz Abstract: Today a great attention is turned to climate changes and their impacts. Since eighties the Regional Climate Models (RCMs) are developed for assessment of future climate at regional scales. But their outputs suffer from many uncertain- ties. Therefore, it is necessary to assess models ability to simulate observed climate characteristics and uncertainties in their outputs before they are applied in consecu- tive studies. In the first chapters of this thesis the sources of uncertainties in climate model outputs and selected methods of climate models performance evaluation are reviewed. Several methods of model performance assessment are then applied to si- mulations of the Czech regional climate model ALADIN-Climate/CZ and selected RCMs from the ENSEMBLES project for the reference period 1961-1990 in the area of the Czech Republic. The attention is paid especially to comparison of simulated and observed spatial and temporal variability of several climatic elements. Within this thesis the...
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Analysis of Climate Model Outputs
Chládová, Zuzana ; Raidl, Aleš (advisor) ; Pišoft, Petr (referee) ; Kliegrová, Stanislava (referee)
Title: Analysis of Climate Model Outputs Author: RNDr. Zuzana Chládová E-mail: zuzana.chladova@gmail.com Department: Department of Meteorology and Environment Protection, Faculty of Mathematics and Physics, Charles University in Prague Supervisor: RNDr. Aleš Raidl, Ph.D. Supervisor's e-mail address: ales.raidl@mff.cuni.cz Consultant: doc. RNDr. Jaroslava Kalvová, CSc. Regional climate models are currently the most important tools regularly used for downscaling outputs of global climate models. This analysis compares control and future runs of the global climate models HadCM3, ECHAM5/OPYC3 and ARPÉGE/OPA and the regional climate models RCAO, RCA3, HIRHAM4, HIRHAM5 and ALADIN- CLIMATE/CZ with observed data and CRU data for the Czech Republic. In the period 1961-1990, the global climate models underestimated the air temperature in comparison with corresponding virtual time series representing real data; mean annual courses and variance of the temperature, on the other hand, were simulated satisfactorily. The results of the regional climate models showed overestimation of the model temperature in winter season, while in other seasons the model temperatures corresponded better with real values and the results of simulation were generally more accurate in comparison with global climate models. Concerning...
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Errors and corrections of atmospheric precipitations measurements
Ptáček, Tomáš ; Sládek, Ivan (advisor) ; Kliegrová, Stanislava (referee)
The thesis approaches the problem of systematic errors that arise in measuring precipitation. These errors lead to underestimation of total rainfall. Size of losses can reach in our latitudes even tens of percent. The systematic errors that contribute most to the underestimation include losses caused by the rain gauge walls wetting, evaporation losses and losses due to aerodynamic effects on the rain gauge precipitation particles. A major section of the thesis is formed by background research, which deals with the issue of systematic measurement errors precipitation. The background research tackles the lack of literature on this topic in the Czech Republic. In the research section of the thesis, two existing correction methods for estimating the size of systematic errors for the Czechoslovak manual rain gauge Metra (method developed in the 80's by Slovak Hydrometeorological Institute and the method described by the dissertation thesis Radoslav Tihlárik) were applied to data of selected four stations in the Czech Republic (Milešovka, Bedřichov - Přehrada, Čáslav - Nové Město and Svratouch) . The first mentioned method was applied to all stations in the Slovak Republic in the nineties. Nevertheless, it has not been used in the Czech Republic so far. The results show that the Tihlárik method gives...
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