National Repository of Grey Literature 8 records found  Search took 0.00 seconds. 
Spatio-temporal distribution of atmospheric aerosol in urban and rural environment
Bendl, Jan ; Hovorka, Jan (advisor) ; Mikuška, Pavel (referee) ; Vojtíšek, Michal (referee)
Air quality in Europe remains a significant environmental concern, affecting the health and quality of life of its population. While stationary network ambient air quality monitoring allows for the observation of main trends, it is not fully representative of personal exposure of citizens due to high spatio-temporal variability of atmospheric aerosol. Therefore, highly time-and- space resolved measurements with state-of-the-art instruments and methods are needed to observe the aerosol variability, dynamics, identify hot-spots, and pollution sources, which are necessary for successful targeted mitigation measures. This thesis addresses this gap focusing on the characterization of spatio-temporal distribution of atmospheric aerosol in inhabited environments. Novel mobile measurement systems were developed and employed to investigate diverse environments, including rural, urban and suburban area. Aerosol source-apportionment were conducted, and the toxicological effects associated with these environments were also investigated. A novel mobile measurement system was developed for personal exposure measurements and pollution mapping in urban and rural environments. The system was used to measure air quality in the Munich subway, revealing high aerosol dynamics with significantly higher concentrations of...
Intercomparison of boundary layer and mixing layer height from models and ground-based measurements
Julaha, Kajal
In this study, we found that the boundary layer height tends to belower in ERA5 and timing for the daily peak also appears to differ\nas compared to ceilometer boundary layer data. In contrast, the ERA5 boundary layer observation was found to agree well with the mixing layer height obtained from the ceilometer. Whereas in comparison to HYSPLIT, GFS and GDAS, observations were found to agree well with ceilometer data while Reanalysis underestimated mixing layer height throughout the year. The seasonal changes in the boundary/mixing layer height were well captured by both models and the ceilometer.
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Dynamics of vertical and horizontal profiles of atmospheric aerosol in planetary boundary layer
Esterlová, Jana ; Hovorka, Jan (advisor) ; Jančík, Petr (referee)
The boundary layer of the atmosphere is a layer of air with thickness about 1 km above the ground. Open-cast mining is one of activities that polutes the air in this layer. It generates particulate matter (PM) mostly in size of aerodynamic diameter 1 - 10 µm - coarse patricles. The companies that does the mining pays for their emissions due to the law. However, these emissions are not experimentraly measured, they are calculated from given equation consisting of factors like the size of mining area, etc. Some papers have shown significantly higher concentrations of Coarse particles (or PM10) in surroundings of the mine. Other papers have found out that the origin of these high concentrations didn't come from the mining activities but is caused due to the activities at the place of measuring or nearby. There aren't many papers that measure the PM concentrations in the air in the mining area. This thesis shows the results of airship measurements in the air layers of the open-cast mine and above them. The experimentral site was brown coal mine Bílina in the North of The Czech Republic in important mining area. The measurements took place in December 2017. For measuring the number and mass concentrations was used APS - Aerodynamic Particle Sizes Spektrometr by TSI which sorts out the data into...
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...
Mathematical modelling of air-flow in geometrically complicated areas
Fuka, Vladimír ; Brechler, Josef (advisor) ; Fürst, Jiří (referee) ; Jaňour, Zbyněk (referee)
The Charles University Large-eddy Microscale Model (CLMM) and its application are presented. It is a numerical model for simulation of turbulent flow and dispersion in the planetary boundary layer. CLMM solves the incompressible Navier-Stokes equations in the Boussinesq approximation and describes turbulence using the large eddy simulation. Three applications of the model are presented. In the first case, the model is applied to the stable boundary layer over a flat terrain. The second case presents the simulations of stably stratified flows over obstacles. The last case deals with the dispersion of a hazardous material within an urban canopy. It was performed in the frame of the COST Action ES1006 and uses the Michelstadt flow and dispersion dataset for model validation.
Dynamics of vertical and horizontal profiles of atmospheric aerosol in planetary boundary layer
Esterlová, Jana ; Hovorka, Jan (advisor) ; Jančík, Petr (referee)
The boundary layer of the atmosphere is a layer of air with thickness about 1 km above the ground. Open-cast mining is one of activities that polutes the air in this layer. It generates particulate matter (PM) mostly in size of aerodynamic diameter 1 - 10 µm - coarse patricles. The companies that does the mining pays for their emissions due to the law. However, these emissions are not experimentraly measured, they are calculated from given equation consisting of factors like the size of mining area, etc. Some papers have shown significantly higher concentrations of Coarse particles (or PM10) in surroundings of the mine. Other papers have found out that the origin of these high concentrations didn't come from the mining activities but is caused due to the activities at the place of measuring or nearby. There aren't many papers that measure the PM concentrations in the air in the mining area. This thesis shows the results of airship measurements in the air layers of the open-cast mine and above them. The experimentral site was brown coal mine Bílina in the North of The Czech Republic in important mining area. The measurements took place in December 2017. For measuring the number and mass concentrations was used APS - Aerodynamic Particle Sizes Spektrometr by TSI which sorts out the data into...
Mathematical modelling of air-flow in geometrically complicated areas
Fuka, Vladimír ; Brechler, Josef (advisor) ; Fürst, Jiří (referee) ; Jaňour, Zbyněk (referee)
The Charles University Large-eddy Microscale Model (CLMM) and its application are presented. It is a numerical model for simulation of turbulent flow and dispersion in the planetary boundary layer. CLMM solves the incompressible Navier-Stokes equations in the Boussinesq approximation and describes turbulence using the large eddy simulation. Three applications of the model are presented. In the first case, the model is applied to the stable boundary layer over a flat terrain. The second case presents the simulations of stably stratified flows over obstacles. The last case deals with the dispersion of a hazardous material within an urban canopy. It was performed in the frame of the COST Action ES1006 and uses the Michelstadt flow and dispersion dataset for model validation.
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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