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Sezónní změny stabilního izotopového složení uhlíku (Δ13C) v aerosolu a plynné fázi na předměstské stanici v Praze
Vodička, Petr; Kawamura, K.; Schwarz, Jaroslav; Ždímal, Vladimír
2022 - Czech
Izotopová frakcionace mezi plynnou a aerosolovou fází je důležitým jevem při studiu atmosférických procesů. V této práci jsme zkoumali sezónní změny poměru stabilních izotopů uhlíku (δ13C) celkového uhlíku (TC, δ13CTC) a organického uhlíku rozpustného ve vodě (WSOC, δ13CWSOC) v jemných aerosolových částicích (PM2,5) a celkového uhlíku plynné fáze (TCgas, δ13CTCgas) na příměstské lokalitě v Praze. In this work, seasonal variations in the stable carbon isotope ratio (δ13C) of total carbon (TC, δ13CTC) and water-soluble organic carbon (WSOC, δ13CWSOC) in fine aerosol\nparticles (PM2.5) as well as in the total carbon of the gas phase (TCgas, δ13CTCgas) were studied. Despite the different seasonal compositions of carbonaceous aerosols, the\nisotope differences (Δδ13C) between the analyzed bulk aerosol parts and gas phases were similar during the seasons. This shows that the fractionation of stable carbon isotopes is a predominantly physical process in which the chemical composition of individual compounds in bulk aerosols does not play a major role.
Keywords:
atmospheric aerosol; gas phase; δ13C, seasonal variation
Available in a digital repository NRGL
Sezónní změny stabilního izotopového složení uhlíku (Δ13C) v aerosolu a plynné fázi na předměstské stanici v Praze
Izotopová frakcionace mezi plynnou a aerosolovou fází je důležitým jevem při studiu atmosférických procesů. V této práci jsme zkoumali sezónní změny poměru stabilních izotopů uhlíku (δ13C) celkového ...
The Impact of the IMO-2020 Shipping Regulation on the Atmospheric Deposition of Sulfur around the Western English Channel and the Use of the V/Ni ratio as a Shipping Marker.
Windell, L.; Bell, T.; White, C.; Schwarz, Jaroslav; Ussher, S.
2022 - English
Anthropogenic aerosols are shown to have a great impact on marine ecosystems and human health, with the shipping industry contributing as a significant source of these\nemissions, and annual growth on the rise. In the marine environment, shipping emissions often dominate atmospheric deposition of sulfur. With around 70% of shipping activity\nbeing carried out within 400 km of the coast, its contribution to atmospheric sulfur is of great interest. The International Maritime Organisation (IMO) introduced a regulation on\n01/01/2020 restricting global marine fuel sulfur content from 3.5% to 0.5% w/w. The vanadium/nickel (V/Ni) ratio has been widely used as a marker of shipping emissions, with the range of 2.5 to 4 indicating shipping activity. The regulation has called into question the viability of the earlier use of the V/Ni ratio.
Keywords:
IMO-2020 Global sulfur cap; shipping emissions; sulfur
Available in a digital repository NRGL
The Impact of the IMO-2020 Shipping Regulation on the Atmospheric Deposition of Sulfur around the Western English Channel and the Use of the V/Ni ratio as a Shipping Marker.
Anthropogenic aerosols are shown to have a great impact on marine ecosystems and human health, with the shipping industry contributing as a significant source of these\nemissions, and annual growth on ...
NMR Aerosolomics Study of Water-Soluble Organic Compounds in Size-Resolved Particulate Matter
Horník, Štěpán; Vodička, Petr; Pokorná, Petra; Schwarz, Jaroslav; Ždímal, Vladimír; Sýkora, Jan
2022 - English
Organic aerosols (OA) account for a significant fraction (10 – 90%) of atmospheric particulate matter (Hallquist et al., 2009). The composition of organic aerosols is very complex and is usually characterized by their water solubility. Water-soluble organic compounds (WSOC) constitute a large fraction of OA (10 – 80%) and consist of chemical species containing oxygenated functional groups such as hydroxyl, carboxyl, or carbonyl groups. NMR spectroscopy represents an alternative to commonly used techniques (gas chromatography-mass spectrometry, liquid chromatography-based techniques) for WSOC analysis. Our recently introduced method, called NMR aerosolomics, allows quantitative analysis of dozens of individual compounds from different aerosol samples. An important part of the characterization of aerosols is their classification by particle size. The analysis of individual compounds in the size-resolved fractions of the WSOC class has been performed only in a few studies that focus mainly on a particular subclass of compounds or use multiple analytical techniques.
Keywords:
NMR; aerosolomics; organic composition
Available in a digital repository NRGL
NMR Aerosolomics Study of Water-Soluble Organic Compounds in Size-Resolved Particulate Matter
Organic aerosols (OA) account for a significant fraction (10 – 90%) of atmospheric particulate matter (Hallquist et al., 2009). The composition of organic aerosols is very complex and is usually ...
Závislost aktivace aerosolu na meteorologických podmínkách
Zíková, Naděžda; Pokorná, Petra; Sedlák, Pavel; Ždímal, Vladimír
2022 - Czech
V šesté hodnotící zprávě IPCC byla nejvyšší hodnota aerosolového forcingu připsána tzv. nepřímému aerosolovému efektu, tedy interakci mezi atmosférickým aerosolem (AA) a oblačností (Arias a kol., 2021). Tato interakce závisí na množství aktivovaných oblačných jader, což je veličina, kterou je náročné měřit i modelovat. Proto byl zkoumán vliv velikostně diferencované aktivace AA na meteorologických veličinách a jevech. Four intensive in-situ campaigns focused on aerosol-cloud interactions were performed in the autumn and spring months from Nov 2018 to Apr 2020 at Milešovka Mountain in Czechia to bring more insight into size-dependent aerosol activation and dependence on its origin for a wide variety of meteorological parameters. Most activated particles were larger than 100 nm, with a mode over 200 nm. For the description of the changes in the activation, no effect of photochemistry was found, in contrast, some dependence on relative humidity, temperature, wind speed, and liquid water content (LWC) proved to be useful. The strongest connection was found between activation and LWC. For LWC below 0.1 g/m3, in the LWC-limited regime, the LWC values and variables effecting the LWC were the main factors influencing the activation, while different parameters could have played a role at LWCs over 0.1 g/m3, in the LWC-independent regime.
Keywords:
atmospheric aerosols; activation; meteorological phenomena
Available in a digital repository NRGL
Závislost aktivace aerosolu na meteorologických podmínkách
V šesté hodnotící zprávě IPCC byla nejvyšší hodnota aerosolového forcingu připsána tzv. nepřímému aerosolovému efektu, tedy interakci mezi atmosférickým aerosolem (AA) a oblačností (Arias a kol., ...
Three Years of Experience with Measurement of Cloud Condensation Nuclei Concentrations Using Cloud Condensation Nuclei Counter CCN-200
Moravec, Pavel; Lhotka, Radek; Ždímal, Vladimír
2022 - English
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)
Keywords:
atmospheric aerosols; CCN; CCN concentration measurement
Available in a digital repository NRGL
Three Years of Experience with Measurement of Cloud Condensation Nuclei Concentrations Using Cloud Condensation Nuclei Counter CCN-200
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 ...
Dendrochronology improves understanding of the charcoal production history, increasing the tourist potential in the Drahany Highlands
Rybníček, Michal; Bajer, A.; Friedl, M.; Knott, R.; Kočár, Petr; Kučera, A.; Novák, J.; Vavrčík, H.; Kolář, Tomáš
2022 - English
Over the last two years, three selected forest sites from Drahany Highlands were examined for traces of human activity. The most frequent traces found, and common to all three sites, were remains of charcoal production. This paper provides an anatomical and dendrochronological analysis of the charcoals found in two charcoal pile remains from each site. The species composition of the charcoals at the southern site was dominated by oak, followed by birch and hornbeam. Fir was more common than oak, beech, poplar, birch and hornbeam at the central site. Fir and beech were found at the northern site. By using dendrochronology, 23 fir, oak and beech charcoals were dated with the oldest sample coming from a central site and dated from the period 1753–1758. Charcoals from the three other charcoal piles fell into the first half of the 19th century. Radiocarbon dating of charcoals selected gave a very wide age range (1640–1955), except for one case (1399–1435). Providing information on the age of a charcoal pile can help raise public awareness and interest in viewing the sites where charcoal burners used to be active in the forests.
Keywords:
Charcoal pile; culture heritage; tourism; tree rings; wood species
Fulltext is available at external website.
Dendrochronology improves understanding of the charcoal production history, increasing the tourist potential in the Drahany Highlands
Over the last two years, three selected forest sites from Drahany Highlands were examined for traces of human activity. The most frequent traces found, and common to all three sites, were remains of ...
GC-MS identification of photochemically generated volatile species of tungsten
Vyhnanovský, Jaromír; Forczek, Sándor; Musil, Stanislav
2022 - English
The presentation focused on the identification of volatile products of photochemical vapor generation of tungsten by GC-MS.
Keywords:
photochemical vapor generation; gas chromatography mass spectrometry; tungsten
Available in digital repository of the ASCR
GC-MS identification of photochemically generated volatile species of tungsten
The presentation focused on the identification of volatile products of photochemical vapor generation of tungsten by GC-MS.
Total and Bioaccessible Fraction of Elements in Urban Aerosol
Mikuška, Pavel; Cigánková, Hana; Hegrová, J.
2022 - English
Atmospheric aerosols have significant impact on health and environment. Elements constitute an important particulate component which have received the attention to understand their environmental and health impacts. Elements enter the human body through inhalation of aerosols causing several health issue (asthma, cardiovascular and respiratory diseases, lung cancer).\nThe potential health effects of elements in PM depend on their toxicity, concentration, and bioaccessibility. It is assumed that the bioaccessible fraction of elements is more relevant for evaluating human health risks than the total concentration of elements. The aim of this study was to determine the total and bioaccessible concentration of elements in urban PM1 and PM2.5 aerosol during four seasons.
Keywords:
aerosol; elements; bioaccessible fraction; PM1; PM2.5
Available in digital repository of the ASCR
Total and Bioaccessible Fraction of Elements in Urban Aerosol
Atmospheric aerosols have significant impact on health and environment. Elements constitute an important particulate component which have received the attention to understand their environmental and ...
Oxidative Potential of PM1 and PM2.5 Urban Aerosol and Associated Elements in Three Simulated Lung Fluids
Cigánková, Hana; Mikuška, Pavel; Hegrová, J.
2022 - English
Mass concentration of particulate matter (PM) has been used in several epidemiologic studies as an indicatior conenecting PM concentrations with human health effects (Ostro, 1993). However, mass concentration of PM doesn´t consider the different compositions and toxicological effects of its components. Majority of PM mass constitutes low-toxicity components, while minority of trace components may have high toxicological activity (Tonne, 2012). Oxidative potential (OP), defined as the ability of PM to induce oxidative stress, is in recent years recognized as one of the main biological mechanisms considered to be contributing to negative impacts from air pollution exposure. Oxidative stress is caused through the capability of PM to generate reactive oxygen species (ROS) within the lung, which leads to pro-inflammatory responses that can ultimately results in cell apoptosis (Borlaza, 2021).
Keywords:
aerosol; oxidative potential; elements
Available in digital repository of the ASCR
Oxidative Potential of PM1 and PM2.5 Urban Aerosol and Associated Elements in Three Simulated Lung Fluids
Mass concentration of particulate matter (PM) has been used in several epidemiologic studies as an indicatior conenecting PM concentrations with human health effects (Ostro, 1993). However, mass ...
Determination of cadmium by chemical vapour generation coupled with atomic fluorescence spectrometry
Štádlerová, Barbora; Sagapova, Linda; Musil, Stanislav
2022 - English
Development of a methodology for determination of cadmium based on chemical vapour generation coupled with atomic fluorescence spectrometry.
Keywords:
atomic fluorescence spectrometry; cadmium; chemical vapour generation
Available in digital repository of the ASCR
Determination of cadmium by chemical vapour generation coupled with atomic fluorescence spectrometry
Development of a methodology for determination of cadmium based on chemical vapour generation coupled with atomic fluorescence spectrometry.
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