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Atmospheric greenhouse gases - new type of measurements in the Czech Republic
Čermáková, Lenka ; Sedlák, Pavel (advisor) ; Zíková, Naděžda (referee)
The current condition, development and functioning of ecosystems is greatly influenced by the ongoing global change, which is probably caused by the increased concentrations of greenhouse gases in the atmosphere originating from human activity. Ecosystems are able to some extent cope with the consequences of global change on their own, and therefore ensure their future preservation. To understand the forces driving global change, we need detailed quality data from long-term observation. Quantification of substance and energy flows in different ecosystems and ecosystem valuation ability to bind air carbon allows us to model their development, both in current conditions and under conditions of global change. This thesis presents the current research methods of atmospheric boundary layer flows, while highlighting their advantages and pointing out their drawbacks. It also enables a better understanding of new methods of observation through the tall towers. The thesis presents some of the existing tall towers and describes their ways and methods of measurement. A part of the thesis is devoted to a tall tower which is planned to be built in the Czech Republic between municipalities Košetice and Křešín u Pacova. It provides an overview of methods, instrumental and technical equipment and facilities of the new tall...
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Spatial variability of precipitation annual cycles
Zíková, Naděžda ; Kalvová, Jaroslava (advisor) ; Pišoft, Petr (referee)
This thesis enquires into the spatial variability of precipitation annual cycles and its representation by regional climate models. Goal is to find suitable metrics that could describe spatial character of the precipitation field and consequently evaluate model results. For complete understanding the issue, there is an introduction to modeling with regional climate models and also parameters of the precipitation in the Czech Republic. The main part of the thesis is an application of different methods of descripiton on the results of the regional climate models (including the Czech model ALADIN) and CRU data. Results of the models are compared to observed data transferred into the regular grid. Each method is applied on the model results and assessed with regard to advantages and disadvantages. The metrics that were found useful are recommended for the further evaluation of the spatial variability of precipitation annual cycles. The ALADIN model seems to be quite successfull, weak points are only modelling of the precipitation in spring and the effect of the continentality and oceanity on the precipitation annual cycles.
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MODEL OPTIMIZING OF THE BIOGAS PLANT OPERATION
Raška, David ; Matějíček, Luboš (advisor) ; Zíková, Naděžda (referee)
Biogas plants are installations for converting of biomass to produce biogas, which is a valuable energy source if a proper management of an anaerobic process is kept. In the Czech Republic are mainly agricultural biogas plant. This work is focused on evaluation of data obtained from a specific biogas plant, which is located in the town Úpice. This plant processes biodegradable waste. The aim of this study was to determine which waste processed are beneficial for the production of biogas. The Data were analyzed by statistical program R. The method used was cluster analysis. For comparsion of clusters was used ANOVA method (analysis of variance). The results of data analysis showed a positive effect on the production of biogas by waste from industrial processing of potatoes, grass and corn silage, rumen contents and dairy waste. Key words: Biogas, plant, anaerobic, fermentation, biodegradable, waste, data analysis
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What is a connection between atmospheric aerosols, meteorological parameters and gaseous pollutants?
Slezáčková Zíková, Naděžda ; Ždímal, Vladimír (advisor) ; Hovorka, Jan (referee) ; Sedlák, Pavel (referee)
Title: What is the connection between atmospheric aerosols, meteorological pa- rameters and gaseous pollutants? Author: RNDr. Naděžda Slezáčková Zíková Department: Department of Meteorology and Environment Protection Supervisor: Ing. Vladimír Ždímal, Dr. Laboratory of Aerosol Chemistry and Physics, Institute of Chemical Process Fun- damentals, Czech Academy of Sciences, v.v.i. Abstract: Five years of atmospheric aerosol (AA) measurements at rural back- ground station Košetice were compared with meteorological records and gaseous pollutants concentrations. The sampling and data analysis of AA data is de- scribed, and the statistical evaluation is done. The variability in the AA con- centrations is significant; the long-term measurements of AA, over the period at least several years, and the differentiation according to the season of the year are thus necessary. The clearly expressed annual cycle of AA concentrations is mainly influenced by two phenomena. From April to September, the total AA concentration cycle is driven mainly by the new particles formation events, from October to March, the concentrations are strongly influenced by particles coming from long-range transport and/or from the regional pollution. The relationship between AA and meteorological parameters, however, is not only season...
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Spatial variability of precipitation annual cycles
Slezáčková Zíková, Naděžda
Title: Spatial variability of precipitation annual cycles Author: Naděžda Zíková Department: Department of Meteorology and Environment Protection Supervisor: doc. RNDr. Jaroslava Kalvová, CSc. Supervisor's e-mail address: Jaroslava.Kalvova@mff.cuni.cz Abstract: This thesis enquires into the spatial variability of precipitation annual cycles and its representation by regional climate models. Goal is to find suitable metrics that could describe spatial character of the precipitation field and con- sequently evaluate model results. For complete understanding the issue, there is an introduction to modeling with regional climate models and also parameters of the precipitation in the Czech Republic. The main part of the thesis is an application of different methods of descripiton on the results of the regional cli- mate models (including the Czech model ALADIN) and CRU data. Results of the models are compared to observed data transferred into the regular grid. Each method is applied on the model results and assessed with regard to advantages and disadvantages. The metrics that were found useful are recommended for the further evaluation of the spatial variability of precipitation annual cycles. The ALADIN model seems to be quite successfull, weak points are only modelling of the precipitation in spring and the effect...
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Prediction of mean hourly values of surface ozone concentrations from passive sampler measurements
Sinkulová, Michaela ; Hůnová, Iva (advisor) ; Zíková, Naděžda (referee)
In terms of air pollution, ground-level ozone is according to current knowledge, contributes the most to damage to ecosystems. To calculate the key indicators of potential damage to ecosystems, such as the exposure index AOT40 and stomatal flux, it is important to know the hourly ozone concentrations, which are the input data for both calculations. For the measurement of O3 air pollution concentrations for the purposes of environmental studies, continuous measurement is not used, but measurement by passive (diffusion) dosimeters, which are exposed for a longer period (usually 1 week-1 month) and thus indicate the average concentration for the relevant longer period. The aim of this diploma thesis is the prediction of hourly concentrations of ground-level ozone from measurements by diffusive samplers, which took place in the period 2006-2010 in Jizerské hory mountains. Monitoring always took place for 2 weeks during the vegetation seasons (April-October) at localities and at various altitudes (714 m above sea level - 1,000 m above sea level). Ogawa diffusive samplers were used. From these average and meteorological concentrations, hourly values of ground-level ozone concentrations were calculated according to the model from professional study and these were compared with measurements from an...
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Cafe indoor air quality assesment
Jüthner, Ludvík ; Zíková, Naděžda (advisor) ; Mašková, Ludmila (referee)
Cafes are specific places with increasing popularity these days. However, the spaces used mainly for meetings, work or studying have not been yet explored in detail from the microclimate point of view, although suboptimal microclimatic conditions can have a negative effect not only on employees but also on customers. The bachelor thesis deals with an evaluation of air quality in coffee shops and juxtaposes its findings with the legislation that defines beneficial conditions for the particular environment. The aim of the thesis is to determine whether the values of temperature, relative moisture including the concentration of PM2,5 and carbon dioxide, based on an example of three specific coffee shops situated in the center of Prague, correspond with the acceptable standard quotes stipulated by the law. To that end, the author explores three assumptions: 1) the selected spaces are not strictly controlled by the Public Health Authority in comparison for instance with hospitals and therefore the recorded values do not correspond with the regulations, 2) the number of people worsens the CO2 values and 3) coffee shops with an entrance facing a busy street show a higher concentration of PM2,5. The results were achieved by experimental measuring in Winter months. The theoretical part defines the concept...
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The measurement of the heterogeneous particles in the steam
Bartoš, Ondřej ; Hrubý, Jan ; Ždímal, Vladimír ; Kolovratník, Michal ; Jiříček, I. ; Moravec, Pavel ; Zíková, Naděžda
The aim of this extended abstract is to reveal the work done as cooperation between several institutions which was presented and published in recent years (Kolovratník, 2014). The formation of droplets in low-pressure steam turbines has a significant impact on the efficiency of energy conversion due to the strongly nonequilibrium nature of this process . The condensed water also erodes the turbine blades. A very important question is to what extent heterogeneous nucleation contributes to the phase transition process . In the case of heterogeneous nucleation , the number of droplets depends only on the number of h eterogeneous particles in the system, whereas in the case of homogeneous nucleation, the number of created droplets is determined rather by the expansion rate - in a faster expansion, greater supersaturation and more droplets are formed until the released condensation enthalpy quenches the nucleation.\nThe specific number of droplets (number of droplets per unit mass of steam) formed in the turbine can be determined by optical probes, developed first by Walters and later in the Czech Republic improved by Petr and Kolovratník. Until recently, no information was available on the relative importance of heterogeneous nucleation in forming these droplets.
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Source apportionment of equivalent black carbon (ebc) at a regional blackground site in central europe
Mbengue, Saliou ; Šerfözö, Norbert ; Schwarz, Jaroslav ; Zíková, Naděžda ; Holubová, Adéla ; Holoubek, I.
This study focuses on a 5-year measurement of equivalent Black carbon (EBC) at a regional background site in Central Europe. The aim is to identify the potential sources of EBC, especially fossil fuel (ff) and biomass burning (bb). Measurements of EBC in PM10 were performed from September 2012 to December 2017 at NAOK (National Atmospheric Observatory Košetice, 49°35ʹ N, 15°05ʹ E), central Czech Republic, with a 7-wavelength aethalometer (AE31, Magee Scientific). The aethalometer model, based on the wavelength dependence of light absorption (Angstrom coefficient), has been used to estimate EBCbb (EBC from biomass burning) and EBCff (EBC from traffic). The influence of local and distant sources has been investigated using the Conditional Probability Function (CPF) and Backward Trajectories Cluster Analysis (BTCA).\nClear seasonal, diurnal and weekly variations of EBC were observed at the NAOK that could be related to the sources fluctuations and transport characteristic. The higher concentrations of EBC were measured during winter (1.00 ±0.87 μg m-3) in comparison with summer (0.44 ±0.29 μg m-3).\n
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