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Identification and detailed characterization of ▫$PM_10$▫ sources in an Alpine valley influenced by a cement plant
Kristina Glojek, Katja Džepina, Griša Močnik, 2023, objavljeni povzetek znanstvenega prispevka na konferenci

Opis: The contribution of traffic and wood burning to particulate matter (PM) across the Alps is widely recognized and studied (Herich et al., 2014 and references therein; Glojek et al., 2020). However, studies on valleys with cement production are scarce (Kim et al., 2003; Rovira et al., 2018) despite its large PM emissions and potential toxic properties (Erik et al., 2022; Weinbruch et al., 2023). We aim to identify and characterize sources’ contribution to the complex mixture of carbonaceous and mineral PM10 in a representative Alpine valley. Quartz filter samples of PM10 were collected daily from December 2020 to December 2021 and analyzed using different chemical techniques. In the same period equivalent black carbon (eBC) measurements were taken with the Aethalometer AE43. The measured species were analyzed using Positive Matrix Factorization (PMF) model (EPA PMF 5.0) with newly added tracers, i. e. source-specific eBC (Sandradewi et al., 2008) and organic species (2-MT, 3-MBTCA, phtalic acid, MSA and oxalate). The final PMF results were compared to online PMF-factors (SoFi Pro) derived from PM10 and PM2.5 elemental measurements (Cooper Xact 625i). Ten factors were identified at the site, including commonly detected biomass burning, traffic, nitrate- and sulfate-rich, aged sea salt and mineral dust. With the added additional organic traces, primary biogenic and secondary oxidation were recognized as well. In addition, two unusual factors were disclosed, contributing 10% to annual PM10. Namely, Cl-rich and a mineral dust-rich factor, which we name the cement kiln factor. We associate these two factors to different processes in the cement plant. The outputs of the study provide vital information about the influence of cement production on PM10 concentrations in complex environments and are useful for PM control strategies and actions.
Ključne besede: PM pollution, carbonaceous aerosols, source apportionment, industry
Objavljeno v RUNG: 10.01.2024; Ogledov: 407; Prenosov: 0
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Equal abundance of summertime natural and wintertime anthropogenic Arctic organic aerosols
Vaios Moschos, Katja Dzepina, Deepika Bhattu, Houssni Lamkaddam, Roberto Casotto, Kaspar R. Daellenbach, Francesco Canonaco, Pragati Rai, Wenche Aas, Silvia Becagli, Giulia Calzolai, Konstantinos Eleftheriadis, Claire E. Moffett, Jürgen Schnelle-Kreis, Mirko Severi, Sangeeta Sharma, Henrik Skov, Mika Vestenius, Wendy Zhang, Hannele Hakola, Heidi Hellén, Lin Huang, Jean-Luc Jaffrezo, Andreas Massling, Jakob K. Nøjgaard, Tuuka Petäjä, Olga Popovicheva, Rebecca J. Sheesley, Rita Traversi, Karl Espen Yttri, Julia Schmale, André S. H. Prévôt, Urs Baltensperger, Imad El Haddad, 2022, izvirni znanstveni članek

Opis: Aerosols play an important yet uncertain role in modulating the radiation balance of the sensitive Arctic atmosphere. Organic aerosol is one of the most abundant, yet least understood, fractions of the Arctic aerosol mass. Here we use data from eight observatories that represent the entire Arctic to reveal the annual cycles in anthropogenic and biogenic sources of organic aerosol. We show that during winter, the organic aerosol in the Arctic is dominated by anthropogenic emissions, mainly from Eurasia, which consist of both direct combustion emissions and long-range transported, aged pollution. In summer, the decreasing anthropogenic pollution is replaced by natural emissions. These include marine secondary, biogenic secondary and primary biological emissions, which have the potential to be important to Arctic climate by modifying the cloud condensation nuclei properties and acting as ice-nucleating particles. Their source strength or atmospheric processing is sensitive to nutrient availability, solar radiation, temperature and snow cover. Our results provide a comprehensive understanding of the current pan-Arctic organic aerosol, which can be used to support modelling efforts that aim to quantify the climate impacts of emissions in this sensitive region.
Ključne besede: Arctic, Organic aerosols, Emission sources, Climate change
Objavljeno v RUNG: 01.03.2022; Ogledov: 1435; Prenosov: 0
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Sarajevo Canton Winter Field Campaign 2018 (SAFICA) : aerosol source apportionment and oxidative potential in a global hotspot
Katja Džepina, 2021, predavanje na tuji univerzi

Objavljeno v RUNG: 13.12.2021; Ogledov: 1328; Prenosov: 0
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Sarajevo Canton Winter Field Campaign 2018 (SAFICA) : aerosol source apportionment and oxidative potential in a global hotspot
Katja Džepina, Griša Močnik, 2021, objavljeni povzetek znanstvenega prispevka na konferenci

Opis: Nowadays, urban centres in countries of the Western Balkan (e.g., Bosnia and Herzegovina, B&H) are experiencing some of the poorest air quality worldwide due to the extensive use of solid fuels and an old vehicle fleet. Western Balkan countries lack state-of-the-science atmospheric research despite high levels of ambient pollution, making the efforts to understand the mechanisms of their air pollution imperative. Sarajevo, the capital of B&H, is situated in a basin surrounded by mountains. During the winter months, topography and meteorology cause significant pollution episodes. The Sarajevo Canton Winter Field Campaign 2018 (SAFICA) took place from Dec 04, 2017 to Mar 15, 2018 with online aerosol measurements and collection of daily, continuous filter PM10 samples for offline laboratory analyses. SAFICA aimed to give the first detailed characterization of the Western Balkans aerosol composition including organic aerosol (OA) to elucidate aerosol emission sources and atmospheric processing and to estimate the adverse health effects. PM10 samples (ntotal=180) were collected at four sites in the Sarajevo Canton: a) Bjelave and b) Pofalići (both urban background); c) Otoka (urban); d) Ivan Sedlo (remote). The urban sites were distributed along the city basin to study the pollutants’ urban evolution and the remote site was chosen to compare urban to background air masses. SAFICA PM10 samples underwent the following offline laboratory chemical analyses: 1) Bulk chemical composition of the total filter-collected water-soluble inorganic and OA by a high-resolution Aerodyne Aerosol Mass Spectrometer (AMS). The measured AMS OA spectra were further analysed by Positive Matrix Factorization (PMF) using the graphical user interface SoFi (Source Finder) to separate OA into subtypes characteristic for OA sources and atmospheric processes. 2) Organic and elemental carbon, water-soluble organic carbon, polycyclic aromatic hydrocarbons (11), levoglucosan, organic acids (16) and 14C total carbon content to evaluate OA chemical composition. 3) Major inorganic anions and cations to evaluate aerosol inorganic species. 4) Aerosol metal content determined by three techniques (AAS, ICP-MS and EESI). 5) Aerosol oxidative potential (OP) by two methods (AA and DTT) to evaluate the ability of particles to generate adverse health effects causing reactive oxygen species. SAFICA online measurements of black carbon (Aethalometer) and the particle number conc. (CPC and OPS) enabled the insights into the daily evolution of primary pollutants and an assessment of aerosol size and number distribution. The combined SAFICA results for field and lab measurements will be presented. Our results show that carbonaceous aerosols make ~2/3 of PM10 mass and the majority are oxygenated, water-soluble OA species with an average OM/OC = 1.9 (Fig.1). Absolute OP levels are very high compared to other sites globally. However, more work is needed to estimate the contributions of different aerosol sources and species to total aerosol OP. Urban air pollution crises in the Western Balkan will be put in the context of local, regional and global air quality. Finally, we will present the scientific questions opened by SAFICA and give suggestions for future studies.
Ključne besede: Sarajevo, Bosnia and Herzegovina, urban air pollution, PM10, PM2.5
Objavljeno v RUNG: 03.09.2021; Ogledov: 1853; Prenosov: 47
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[Rasprava] : Okrugli stol održan 26. siječnja 2017. u palači Akademije u Zagrebu
Katja Džepina, 2017, objavljeni znanstveni prispevek na konferenci

Opis: Temeljna namjera održavanja okruglog stola i objave ove knjige bila je da se pri obradi pravne zaštite zraka mora polaziti od struke koja je mjerodavna za pitanje očuvanja kvalitete zraka. Pravni pristup tom važnom području mora se na to nastaviti. Pritom se moraju poštivati temeljna pravila odgovarajuće struke, zahtjevi koje ona postavlja i prijedlozi kako poboljšati trenutačno stanje. Rasprava je pokazala da je zadovoljavajući učinak moguć jedino ako primjenjujemo takav pristup. Zadatak je pravnika pravno uobličiti ono što zahtijeva struka koja se bavi kvalitetom zraka. Takav je zahtjev postavljen i u raspravi.
Ključne besede: Pravna zaštita zraka, Okrugli stol, Hrvatska Akademija znanosti i umjetnosti, Zagreb, Republika Hrvatska
Objavljeno v RUNG: 14.06.2021; Ogledov: 1868; Prenosov: 0
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Utjecaj atmosferskih lebdećih čestica na ljudsko zdravlje : predavanje na 2. Studentskom kongresu okolišnog zdravlja s medjunarodnim sudjelovanjem, Rijeka, Hrvatska, 5. 6. 2018
Katja Džepina, 2018, vabljeno predavanje na konferenci brez natisa

Objavljeno v RUNG: 29.05.2021; Ogledov: 1596; Prenosov: 0
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