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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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Three Years of Experience with Measurement of Cloud Condensation Nuclei Concentrations Using Cloud Condensation Nuclei Counter CCN-200
Moravec, Pavel ; Lhotka, Radek ; Ždímal, Vladimír
Aerosol particles in the atmosphere that allow water vapor to condense and form cloud droplets are called Cloud Condensation Nuclei (CCN). Elevated concentrations of \nCCN tend to increase the concentration and decrease the size of droplets. This can lead to suppression of precipitation in shallow and short-lived clouds and to greater convective \noverturning and more precipitation in deep convective clouds. The response of cloud properties and precipitation processes to increasing anthropogenic aerosol concentrations represents one of the largest uncertainties in the current understanding of climate change. One of the fundamental challenges is to determine the ability of aerosol particles to act as CCN under relevant atmospheric conditions. Knowledge of the spatial and temporal distribution in the atmosphere is essential to incorporate the effects of CCN into meteorological models of all scales, Huang et al. (2007). Long-term CCN measurements are performed at aerosol monitoring sites such as those forming ACTRIS (Aerosols, Clouds and Trace Gases Research Infrastructure) network. In this paper, we present the three-year experience of measuring CCN concentrations over the National Atmospheric Observatory Košetice (NAOK), a rural background site in the Czech Republic. The first results of these measurements were presented by Mishra et al. (2022)
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Ambient Organic Aerosol Origin at Rural Background Site in the Czech Republic.
Lhotka, Radek
Atmospheric aerosol (AA) are ubiquitous particles in the atmosphere that influence Earth’s climatic system, environmental interactions,\nand human health. AA is emitted directly from primary sources or formed in the atmosphere via the oxidation of gas-phase precursors\nwith subsequent partitioning resulting in low-volatility products into the particle phase. Among AA, great interest is dedicated to organic\naerosol (OA) since it can represent from 20 to 90% of the total submicron mass.
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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
Plný tet: SKMBT_C22020011314380 - PDF
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A 5 year´s source apportionment study of black carbon from biomass burning and fossil fuel combustion at a rural background site
Mbengue, Saliou ; Šerfözö, Norbert ; Schwarz, Jaroslav ; Zíková, Naděžda ; Holubová, Adéla ; Holoubek, Ivan
The impacts of Black Carbon (BC) on adverse public health and Earth’s climate system have been recognized and evidenced in recent decades. Most of the studies on BC were conducted in urban/traffic areas. There are relatively few studies using real-time measurements of BC at rural background areas, especially in Central Europe. This study is a 5-year characterization of BC from biomass burning (BCbb) and fossil fuel combustion (BCff) at the National Atmospheric Observatory Košetice (49°35ʹ N, 15°05ʹ E), in central Czech Republic. The measurements of BC in PM10 were performed at 4 m above the ground with a multiple wavelength aethalometer (AE31, Magee Scientific). Paralell measurement of trace gases (NO2, NOx and SO2), biomass burning tracers (levoglucosan and mannosan) and meteorological parameters (temperature, wind speed and direction) were also performed at the station.
Plný tet: SKMBT_C22019110512331 - PDF
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Původ znečištění ovzduší na základě ročního měření PM2.5 a PM10 na dvou městských pozaďových stanicích v Praze.
Schwarz, Jaroslav ; Pokorná, Petra ; Rychlík, Š. ; Škáchová, H. ; Smolík, Jiří ; Ždímal, Vladimír ; Vlček, O. ; Hůnová, I.
Hmotnostní koncentrace atmosférického aerosolu (particulate matter – PM) ve městech odpovídá součtu koncentrace naměřené na pozaďových stanicích a rozdílu mezi městskou a pozaďovou stanicí. Z tohoto důvodu je při vysokých pozaďových koncentracích PM výsledek opatření snižujících míru emisí malý. Většina uváděných episod zvýšených koncentrací PM v zimě ve městech střední Evropy je způsobena zdroji lokálního nebo regionálního původu ze spalování uhlí a/nebo biomasy za účelem vytápění. Zlepšení kvality ovzduší ve městech je možné za předpokladu pochopení kauzalit především pokud se jedná o atmosférický aerosol a jeho koncentrace, zdroje a původ.\nCílem práce bylo určit původ znečištění ovzduší v Praze na základě ročního paralelního měření atmosférického aerosolu na dvou městských pozaďových stanicích.
Plný tet: SKMBT_C22020011314370 - PDF
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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, Vladimír
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 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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NMR Aerosolomics as a Tool to Distinguish Various Types of Aerosol Samples.
Horník, Štěpán ; Schwarz, Jaroslav ; Ždímal, Vladimír ; Sýkora, Jan
In the recent study, the summer and winter aerosol samples were analyzed using NMR aerosolomics approach. The samples were collected in Prague-Suchdol during summer 2008 and winter 2009 in two different particle size fractions - PM2.5 and PM 10. Around 50 compounds were identified in each aerosol spectrum owing to the comprehensive library. The profile of 86 identified compounds, which were identified in the samples altogether, served as an input data for statistical analysis. Multivariate statistical analysis clearly discriminates the two groups studied. Furthermore, it is possible to determine the most significant compounds.
Plný tet: SKMBT_C22019041212342 - PDF
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