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New particle formation measurement down to 1.2 nm at noak
Holubová, Adéla ; Zíková, Naděžda ; Ždímal, Vladimír
Atmospheric aerosols influence Earths climatic system and human health. Role of aerosols in climatic system still includes uncertainties strongly influencing model simulations (Zhao et al. \n2018). One of the uncertainties is caused by secondary aerosol formation and their consequent growth. Nucleation of aerosol particles is a process determined by presence of aerosol precursors in atmosphere and by ambient atmospheric conditions (Dada et al. 2017). \nSince new particle formation (NPF) events have been observed in many types of environment (Kulmala et al. 2004), we have focused on NPF events at background station in the Czech Republic, representative for central European region. In this study we investigate NPF process of aerosol clusters from 1.2 nm in size.\n
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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
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22020011314380 - PDF
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The origin of air pollution on the basis of one year measurements of PM2.5 and PM10 at two urban background stations in Prague
Schwarz, Jaroslav ; Pokorná, Petra ; Rychlík, Š. ; Škáchová, H. ; Smolík, Jiří ; Ždímal, Vladimír ; Vlček, O. ; Hůnová, I.
The particulate matter (PM) mass concentration in cities corresponds to the sum of the concentrations measured at the background stations and the difference between the city and background stations. For this reason, at high background concentrations of PM, the result of emission reduction measures is low. Most of the reported episodes of increased PM concentrations in winter in central European cities are caused by sources of local or regional origin from the combustion of coal and / or biomass for heating purposes. Improvement of air quality in cities is possible provided that causality is understood, especially when it comes to atmospheric aerosol and its concentration, sources and origin.\nThe aim of the work was to determine the origin of air pollution in Prague on the basis of one year parallel measurements of atmospheric aerosol at two urban background stations.\n\n
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22020011314370 - PDF
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Dependence of activated aerosol on horizontal hydrometeor type.
Zíková, Naděžda ; Pokorná, Petra ; Pešice, Petr ; Sedlák, Pavel ; Ždímal, Vladimír
Atmospheric aerosol (AA) affects not only cloud formation, but also other cloud properties such as droplet size distribution, chemical composition, etc. The interaction between AA and cloud does not have to be investigated only by aerial measurements, but the same processes can be observed in fog and low clouds. An example of a station suitable for such research is Milešovka station, where the fog (or low clouds) is 55% of the time. Here, measurements were made to describe the effect of fog on the number size distributions of AA and activated nucleation nuclei.
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Vertical profile of concentration and flow of aerosol particles over arable land
Zapletal, Miloš ; Hovorka, J. ; Hladík, J. ; Juráň, Stanislav
At present, the immission load of the territory and population by solid / liquid or mixed particles with the size of 1 nm - 100 μm suspended in the atmosphere, or PM, is one of the biggest problems not only in the Czech Republic but practically throughout Europe. High PM concentrations are associated with a large number of health problems. These include respiratory disorders and an increased risk of lung and skin cancer (WHO, 2006). In the Czech Republic, long-term exposure to PM is an important factor responsible for reducing the quality of life of the population. Among the most serious effects in terms of overall health burden is a significant reduction in life expectancy (WHO, 2006). Transport and industrial activities are generally considered to be the main source of PM10 particles. Existing information on the chemical composition, size distribution, secondary particle fraction and deposition flux of particles on different types of surfaces is still incomplete. Aerosol concentration measurements have been performed in many cities at street level or for personal exposure assessment (Kaur et al., 2005, Longley et al., 2004). Eddy covariance measurements of particulate emission flux over large urban agglomerations were performed (Dorsey et al., 2002, Järvi et al., 2009, Martin et al., 2009, Deventer et al., 2013). Direct measurement of the emission flux of the eddy particles by the covariation method provided information on the upward air flow and vertical particle exchange over some urban agglomerations (eg Manchester, London, Helsinki). A description of the measurement of the eddy particle flow by the covariance method from an aircraft is given in Buzorius et al. (2006). Less information exists on the emission flux of particles above different types of sources at different heights, eg above arable land, opencast coal mine or local fireplaces.
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ACTRIS IMP – ÚČAST ČESKÉ REPUBLIKY V NÁRODNÍCH VÝZKUMNÝCH INFRASTRUKTURÁCH A TÉMATICKÝCH CENTRECH ACTRIS
Ondráček, Jakub ; Váňa, M. ; Klánová, J. ; Holoubek, Ivan ; Ždímal, V.
ACTRIS (The Aerosol, Clouds and Trace Gases Research Infrastructure) je panevropskou výzkumnou infrastrukturou, jejímž hlavním cílem je tvorba vysoce kvalitních dat a podávání informací o krátkodobých složkách atmosféry a o procesech vedoucích ke změnám těchto složek v přírodním a kontrolovaném laboratorním prostředí. ACTRIS je dlouhodobou aktivitou (již od roku 2012, viz. Obr. 1) více než 100 partnerských organizací po celé Evropě, jejichž cílem je integrace, harmonizace a distribuce vysoce kvalitních vědeckých výstupů poskytovaných nejlepšími pracovišti atmosférického výzkumu v (prozatím) 22 evropských zemích. ACTRIS je logickým pokračováním 15-tiletého rozvoje velkých výzkumných infrastruktur financovaného členskými státy a evropskou komisí (EC) prostřednictvím programu výzkumných infrastruktur (Research Infrastructure programme) zahrnujících např. Projekty EARLINET, EUSAAR, CREATE a CLOUDNET.
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