|
|
Interannual temperature variability in Europe
Švábek, David ; Huth, Radan (advisor) ; Mikšovský, Jiří (referee)
This master thesis is focused on interannual variability of air temperature throughout Europe and its long-term trends. Alongside changes in average air temperature, it is the changes in variability that fundamentally affect meteorological extremes. Therefore, those are fundamental climate characteristics at which we do not know yet if they are changing and if so, in what direction. The changes seem to differ between individual regions, seasons and timescales. Changes behave differently when they are short-term (interday to interseasonal) and when they are long-term (interannual). These interannual changes are the main topic of this master thesis. In the review part of the thesis, the scientific literature is summarized, supplemented by changes in interannual variability both globally and regionally for the territory of Europe, namely for individual seasons. The objective of the practical part of the paper is the analysis of long-term interannual temperature variability in the period from 1 March 1961 to 28 February 2018, for each season separately. The objective of this work is not only to quantify the trends of interannual temperature variability but also to compare them among five different climate databases, as most scientific studies that analyse long-term changes in variability have been...
|
|
|
Nonstationarity of the effects of modes of atmospheric circulation variability on surface climate elements
Hynčica, Martin ; Huth, Radan (advisor) ; Dobrovolný, Petr (referee) ; Beck, Christoph (referee)
Circulation modes are highly correlated, yet often distant areas detected in a field of a circulation variable, such as sea level pressure, geopotential heights, wind speed, and wind components. They consist typically of two or more action centres, which simultaneously weaken or strengthen, hence affecting the intensity and direction of atmospheric circulation and consequently surface climatic elements, such as temperature and precipitation. Temporal variability of action centres affects spatiotemporal distribution of impact on surface climatic variables. The availability of gridded datasets allows investigation of temporal behaviour of action centres and its impact on surface climatic variables on long time scales over large regions, which is, therefore, the main scientific topic of this work. Due to a large amount of reanalyses differing in e.g. assimilated type of data and model used for their calculation, the comparison of representation of circulation modes and their temporal evolution of relationships with surface climatic elements is conducted between reanalyses. Circulation modes in reanalyses assimilating both surface and upper troposphere/satellite data (ERA40, JRA-55, NCEP-1) are mostly similar whereas the 20CRv2c reanalysis, which utilizes surface data only, contains biases. Although...
|
|
|
Temporal stability of effects of the 11-year solar cycle on circulation conditions in central Europe
Paličková, Lea ; Huth, Radan (advisor) ; Halenka, Tomáš (referee)
Temporal stability of effects of the 11-year solar cycle on circulation conditions in central Europe Abstract The aim of this master thesis is to determinewhether circulation conditions in central Europe are affected by variable solar activity. Circulation type classification by Beck (2000) is used here to evaluate the solar effects. Circulation characteristics of circulation are available back to 1780. This master thesis proves that the solar cycle effects on circulation conditions in central Europe are not stationary in time. It was demonstrated that the frequency of individual circulation types varies significantly, depending on the length of studied period. The impact of solar variability on circulation conditions in central Europe is more significant when a shorter time period is being considered. It was also found that the response of circulation characteristics on solar variability is not immediate. There have not been clear results if there exists a linear trend on lagged response of solar variability on circulation characteristics. Linear trend has been found only for a whole year dataset with a lagged response within a year. This thesis proves that the solar cycle effects on troposphere are highly variable, so it is very difficult to define them straightforward. Keywords: atmospheric circulation,...
|
|
|
The actual stage of the issue of the climate classification
Minářová, Jana ; Müller, Miloslav (advisor) ; Huth, Radan (referee)
The aim of this work is to create an overview of current climate classifications and to demonstrate the dependence of these classifications on the type of dataset and on the studied period. In the first part resulting from the available information in the literature the standard division of climate classifications into effective and genetic has been kept. Nevertheless, the first outnumber branch has been divided further into four groups according to their main characters: classifications (i) thermic, (ii) determined by vegetation, meteorological and climatic elements, (iii) delimited by marginal values of created indexes and (iv) based on symbols of landscape. In the second part the influence of selected data (station vs. gridded) on the resulting representation of climate classification is demonstrated using the comparative method. On the basis of station data accessible online for the Czech Republic and Germany supplemented for earlier periods by material from printed publications, the dependence of the studied period on the final output of climate classification is demonstrated. In most cases, there was a change of "Dfb" - (cold climate without dry season with warm summer) - on "Cfb" - (temperate climate without dry season with warm summer). The complexity of the issue of creating climate classifications...
|
|
|
Spatial patterns of links between temperature extremes and cardiovascular mortality in the Czech Republic
Urban, Aleš ; Kyselý, Jan (advisor) ; Huth, Radan (referee) ; Dobrovolný, Petr (referee)
Name of the thesis: Spatial patterns of links between temperature extremes and cardiovascular mortality in the Czech Republic Author: Mgr. Aleš Urban Previous studies have examined relationships of high and low air temperatures to mortality due to cardiovascular diseases (CVDs) in the Czech Republic as a whole. Much less has been understood about possible regional differences in the heat and cold effects on mortality. Within four papers published in international peer-reviewed journals, the author of this thesis investigated links between extreme temperatures and CVD mortality in the Czech Republic while considering in particular differences between (i) urban and rural areas, (ii) regions with different socioeconomic status, and (iii) regions with different physical-environmental conditions. Various biometeorological approaches were compared in order to identify meteorological characteristics affecting heat- and cold-related mortality. Excess mortality was determined as differences between observed and expected daily values, the latter being adjusted for long-term changes, annual and weekly cycles, and epidemics of influenza/acute respiratory infections. Air temperature, biometeorological indices (including the Universal Thermal Climate Index, Apparent Temperature, and Physiologically Equivalent...
|
|
|
The applicability of the Hess-Brezowsky synoptic classification to the description of climate elements in Europe
Sýkorová, Petra ; Huth, Radan (advisor) ; Racko, Stanislav (referee)
This thesis deals with the applicability of the Hess-Brezowsky synoptic classification to the description of climate elements, minimal and maximal temperatures and precipitation, in Europe. The first part of the thesis is an overview of the knowledge concerning circulation classifications (with emphasis on the Hess-Brezowsky synoptic classification) and its applicability to the description of climatic elements. In the second part of this thesis, the suitability of the Hess-Brezowsky classification for this purpose in the European domain is analyzed, using the two-sample Kolmogorov-Smirnov test. The test was performed on ECA&D data from 113 climatic stations for the years 1961 - 2000. The suitability of the classification for describing climatic elements at a given station was assessed according to the percentage of the synoptic types, during which the elements' probability distribution functions differed from the rest of the values. The classification was deemed most suitable for describing climatic elements in Germany and its neighboring states and least suitable in the Mediterranean and Eastern Europe. The classification was more suitable for the description of minimal and maximal temperatures than precipitation and less suitable for description of all climatic elements in the summer months than...
|
|
|
Changes in climate elements in central Europe and the Czech Republic from the mid-20th century, focusing on autumn
Maryško, Kryštof ; Huth, Radan (advisor) ; Cahynová, Monika (referee)
This thesis deals with climate elements changes in Central Europe in the 2nd half of the 20th century which are being compared to changes in global and European scale. The entire thesis is divided into three main chapters according to the climate elements. The most described are temperature indicators which the authors of papers study most frequently. Also the precipitation forms a separate chapter, while other elements are all summarized in one chapter, because there are not that many studies about them. The average annual temperature and precipitation trends calculated for Europe or the world were similar to those in Central Europe. As for the temperature indicators, during the 2nd half of the 20th century warming was found in most cases and insignificant trends prevailed for precipitation indicators. Among the seasonal changes in climate, autumn stood out. Its trends were in some cases (especially for temperature indicators) different from the other seasons. Whilst there is warming in Central Europe in spring, summer and winter, it cools in autumn. Keywords: climate elements, long-term changes, Central Europe, autumn
|
|
| |
|
|
The altitudinal dependence of long-term surface air temperature changes
Krauskopf, Tomáš ; Huth, Radan (advisor) ; Pokorná, Lucie (referee)
The altitudinal dependence of long-term surface air temperature changes Abstract In this work there is summarized the scientific literature which is focused on the spatial distribution of long-term surface air temperature changes, specifically on the altitudinal dependence of warming rate. In this text this dependence is analyzed both globally and in several major mountain regions. The greatest attention is paid to the Swiss Alps, where is the largest network of weather stations and there should be achieved reliable results. Furthermore, this work refers to mechanisms that cause different rates of warming at different altitudes, such as snow-albedo feedback or changes in the frequency of fog and cloud. The aim of the practical part is then to analyze surface temperature trends in the Czech Republic and to assess the altitudinal dependence of long-term surface air temperature changes in our country. Keywords: climate change, temperature, trends, altitude
|
|
|
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...
|
guest ::
