1. Compositional changes of ▫$PM_2.5$▫ in NE Spain during 2009–2018 : a trend analysis of the chemical composition and source apportionmentMarten in 't Veld, Andrés Alastuey, Marco Pandolfi, Fulvio Amato, Noemí Perez, Cristina Reche, Marta Via, Maria Cruz Minguillon, Miguel Escudero, Xavier Querol, 2021, izvirni znanstveni članek Ključne besede: PM2.5, aerosol, source apportionment
Objavljeno v RUNG: 10.05.2024; Ogledov: 11; Prenosov: 0
 Celotno besedilo (3,62 MB) |
2. Apportionment of black and brown carbon spectral absorption sources in the urban environment of Athens, Greece, during winterDimitris G. Kaskaoutis, Georgios Grivas, Iasonas Stavroulas, Aikaterini Bougiatioti, Eleni Liakakou, Umesh Chandra Dumka, Evangelos Gerasopoulos, Nikolaos Mihalopoulos, 2021, izvirni znanstveni članek Opis: This study examines the spectral properties and source characteristics of absorbing aerosols (BC: Black Carbon; BrC: Brown Carbon, based on aethalometer measurements) in the urban background of Athens during December 2016–February 2017. Using common assumptions regarding the spectral dependence of absorption due to BC (AAEBC = 1) and biomass burning (AAEbb = 2), and calculating an optimal AAEff value for the dataset (1.18), the total spectral absorption was decomposed into five components, corresponding to absorption of BC and BrC from fossil-fuel (ff) combustion and biomass burning (bb), and to secondary BrC estimated using the BC-tracer minimum R-squared (MRS) method. Substantial differences in the contribution of various components to the total absorption were found between day and night, due to differences in emissions and meteorological dynamics, while BrC and biomass burning aerosols presented higher contributions at shorter wavelengths. At 370 nm, the absorption due to BCff contributed 36.3% on average, exhibiting a higher fraction (58.1%) during daytime, while the mean BCbb absorption was estimated at 18.4%. The mean absorption contributions due to BrCff, BrCbb and BrCsec were 6.7%, 32.3% and 4.9%, respectively. The AbsBCff,370 component maximized during the morning traffic hours and was strongly correlated with NOx (R2 = 0.76) and CO (R2 = 0.77), while a similar behavior was seen for the AbsBrCff,370 component. AbsBCbb and AbsBrCbb levels escalated during nighttime and were highly associated with nss-K+ and with the organic aerosol (OA) components related to fresh and fast-oxidized biomass burning (BBOA and SV-OOA) as obtained from ACSM measurements. Multiple linear regression was used to attribute BrC absorption to five OA components and to determine their absorption contributions and efficiencies, revealing maximum contributions of BBOA (33%) and SV-OOA (21%). Sensitivity analysis was performed in view of the methodological uncertainties and supported the reliability of the results, which can have important implications for radiative transfer models.
Ključne besede: spectral absorption, black carbon, brown carbon, fossil fuel, biomass burning, source apportionment
Objavljeno v RUNG: 10.05.2024; Ogledov: 11; Prenosov: 0
Gradivo ima več datotek! Več... |
3. Ambient carbonaceous aerosol levels in Cyprus and the role of pollution transport from the Middle EastAliki Christodoulou, Iasonas Stavroulas, Mihalis Vrekoussis, Maximillien Desservettaz, Michael Pikridas, Elie Bimenyimana, Jonilda Kushta, Matic Ivančič, Martin Rigler, Philippe Goloub, 2023, izvirni znanstveni članek Opis: Abstract. The geographical origin and source apportionment of submicron carbonaceous aerosols (organic aerosols, OAs, and black carbon, BC) have been investigated here for the first time, deploying high time-resolution measurements at an urban background site of Nicosia, the capital
city of Cyprus, in the eastern Mediterranean. This study covers a half-year
period, encompassing both the cold and warm periods with continuous
observations of the physical and chemical properties of PM1 performed
with an Aerosol Chemical Speciation Monitor (ACSM), an aethalometer,
accompanied by a suite of various ancillary offline and online measurements. Carbonaceous aerosols were dominant during both seasons (cold and warm periods), with a contribution of 57 % and 48 % to PM1, respectively, and exhibited recurrent intense nighttime peaks (> 20–30 µg m−3) during the cold period, associated with local domestic heating. The findings of this study show that high concentrations of sulfate (close to 3 µg m−3) were continuously recorded, standing among the highest ever reported for Europe and originating from the Middle East region. Source apportionment of the OA and BC fractions was performed using the
positive matrix factorization (PMF) approach and the combination of two
models (aethalometer model and multilinear regression), respectively. Our
study revealed elevated hydrocarbon-like organic aerosol (HOA)
concentrations in Nicosia (among the highest reported for a European urban
background site), originating from a mixture of local and regional
fossil fuel combustion sources. Although air masses from the Middle East had
a low occurrence and were observed mostly during the cold period, they were
shown to strongly affect the mean concentrations levels of BC and OA in
Nicosia during both seasons. Overall, the present study brings to our
attention the need to further characterize primary and secondary
carbonaceous aerosols in the Middle East, an undersampled region
characterized by continuously increasing fossil fuel (oil and gas) emissions
and extreme environmental conditions, which can contribute to photochemical
ageing.
Ključne besede: PM1, BC, source apportionment, Cyprus, long range transport
Objavljeno v RUNG: 10.05.2024; Ogledov: 11; Prenosov: 0
Celotno besedilo (5,55 MB)
Gradivo ima več datotek! Več... |
4. Rolling vs. seasonal PMF : real-world multi-site and synthetic dataset comparisonMarta Via, Gang Chen, Francesco Canonaco, Kaspar Rudolf Daellenbach, Benjamin Chazeau, Hasna Chebaicheb, Jianhui Jiang, Hannes Keernik, Chunshui Lin, Nicolas Marchand, 2022, izvirni znanstveni članek Opis: Abstract. Particulate matter (PM) has become a major concern in terms of human health
and climate impact. In particular, the source apportionment (SA) of organic
aerosols (OA) present in submicron particles (PM1) has gained relevance
as an atmospheric research field due to the diversity and complexity of its
primary sources and secondary formation processes. Moreover, relatively
simple but robust instruments such as the Aerosol Chemical Speciation
Monitor (ACSM) are now widely available for the near-real-time online
determination of the composition of the non-refractory PM1. One of the
most used tools for SA purposes is the source-receptor positive matrix
factorisation (PMF) model. Even though the recently developed rolling PMF technique has
already been used for OA SA on ACSM datasets, no study has assessed its
added value compared to the more common seasonal PMF method using a practical
approach yet. In this paper, both techniques were applied to a synthetic
dataset and to nine European ACSM datasets in order to spot the main output
discrepancies between methods. The main advantage of the synthetic dataset
approach was that the methods' outputs could be compared to the expected
“true” values, i.e. the original synthetic dataset values. This approach
revealed similar apportionment results amongst methods, although the
rolling PMF profile's adaptability feature proved to be advantageous, as it
generated output profiles that moved nearer to the truth points. Nevertheless,
these results highlighted the impact of the profile anchor on the solution,
as the use of a different anchor with respect to the truth led to
significantly different results in both methods. In the multi-site study,
while differences were generally not significant when considering year-long
periods, their importance grew towards shorter time spans, as in intra-month
or intra-day cycles. As far as correlation with external measurements is
concerned, rolling PMF performed better than seasonal PMF globally for the ambient
datasets investigated here, especially in periods between seasons. The results of this
multi-site comparison coincide with the synthetic dataset in terms of
rolling–seasonal similarity and rolling PMF reporting moderate improvements. Altogether, the
results of this study provide solid evidence of the robustness of both
methods and of the overall efficiency of the recently proposed rolling PMF
approach.
Ključne besede: particulate matter, synthetic dataset comparison, source apportionment, organic aerosols
Objavljeno v RUNG: 10.05.2024; Ogledov: 11; Prenosov: 0
Celotno besedilo (2,03 MB)
Gradivo ima več datotek! Več... |
5. Increase in secondary organic aerosol in an urban environment : Increase in secondary organic aerosol in an urban environmentMarta Via, Maria Cruz Minguillon, Cristina Reche, Xavier Querol, Andrés Alastuey, 2021, izvirni znanstveni članek Opis: The evolution of fine aerosol (PM1) species as well as the contribution of potential sources to the total organic aerosol (OA) at an urban background site in Barcelona, in the western Mediterranean basin (WMB) was investigated. For this purpose, a quadrupole aerosol chemical speciation monitor (Q-ACSM) was deployed to acquire real-time measurements for two 1-year periods: May 2014–May 2015 (period A) and September 2017–October 2018 (period B). Total PM1 concentrations showed a slight decrease (from 10.1 to 9.6 μgm�3 from A to B), although the relative contribution of inorganic and organic compounds varied significantly. Regarding inorganic compounds, SO42- , black carbon(BC) and NH4+ showed a significant decrease from period
A to B (21 %, 18% and 9 %, respectively), whilst NO3- concentrations were higher in B (8 %). Source apportionment
revealed OA contained 46% and 70% secondary OA (SOA) in periods A and B, respectively. Two secondary oxygenated OA sources (OOA) were differentiated by their oxidation status (i.e. ageing): less oxidized (LO-OOA) and more oxidized (MO-OOA). Disregarding winter periods, when LO-OOA production was not favoured, LO-OOA transformation into MO-OOA was found to be more effective in
period B. The lowest LO-OOA-to-MO-OOA ratio, excluding winter, was in September–October 2018 (0.65), implying an accumulation of aged OA after the high temperature and solar radiation conditions in the summer season. In addition to temperature, SOA (sum of OOA factors) was enhanced by exposure to NOx-polluted ambient and other pollutants, especially to O3 and during afternoon hours. The anthropogenic primary OA sources identified, cooking-related
OA (COA), hydrocarbon-like OA (HOA), and biomass burning OA (BBOA), decreased from period A to B in both absolute concentrations and relative contribution (as a whole, 44% and 30 %, respectively). However, their concentrations and proportion to OA grew rapidly during highly polluted episodes. The influence of certain atmospheric episodes on OA sources was also assessed. Both SOA factors were boosted with long- and medium-range circulations, especially those coming from inland Europe and the Mediterranean (triggering mainly MO-OOA) and summer breeze-driven regional circulation (mainly LO-OOA). In contrast, POA was
enhanced either during air-renewal episodes or stagnation anticyclonic events.
Ključne besede: aerosol, organic aerosol, source apportionment, PM1, particulate matter
Objavljeno v RUNG: 10.05.2024; Ogledov: 11; Prenosov: 0
Celotno besedilo (4,93 MB)
Gradivo ima več datotek! Več... |
6. Identification and detailed characterization of ▫$PM_10$▫ sources in an Alpine valley influenced by a cement plantKristina 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: 656; Prenosov: 0
Gradivo ima več datotek! Več... |
7. Towards a better understanding of fine PM sources : online and offline datasets combination in a single PMFMarta Via, Jesús Yus-Díez, Francesco Canonaco, Jean-Eudes Petit, Philip Hopke, Cristina Reche, Marco Pandolfi, Matic Ivančič, Martin Rigler, Andre S. H. Prevot, 2023, izvirni znanstveni članek Ključne besede: multi-time resolution, source apportionment, submicronic particulate matter, positive matrix factorisation, PMF, multilinear engine, SoFi, ME2, organic sources, metals
Objavljeno v RUNG: 24.10.2023; Ogledov: 752; Prenosov: 6
Celotno besedilo (3,23 MB)
Gradivo ima več datotek! Več... |
8. Characterizing the sources of ambient ▫$PM_10$▫ organic aerosol in urban and rural Catalonia, SpainMarten in ʼt Veld, Peeyush Khare, Yufang Hao, Cristina Reche, Noemí Perez, Andrés Alastuey, Jesús Yus-Díez, Nicolas Marchand, Andre S. H. Prevot, Xavier Querol, Kaspar Rudolf Daellenbach, 2023, izvirni znanstveni članek Ključne besede: PM10, chemical composition, organic aerosols, SOA, source apportionment
Objavljeno v RUNG: 23.10.2023; Ogledov: 877; Prenosov: 6
Celotno besedilo (7,72 MB)
Gradivo ima več datotek! Več... |
9. Source apportionment study on particulate air pollution in two high-altitude Bolivian cities: La Paz and El AltoValeria Mardoñez, Marco Pandolfi, Lucille Joanna S. Borlaza, Jean-Luc Jaffrezo, Andrés Alastuey, Jean-Luc Besombes, Isabel R. Moreno, Noemí Perez, Griša Močnik, Patrick Ginot, 2023, izvirni znanstveni članek Opis: La Paz and El Alto are two fast-growing, high-altitude Bolivian cities forming the second-largest metropolitan area in the country. Located between 3200 and 4050 m a.s.l. (above sea level), these cities are home to a burgeoning population of approximately 1.8 million residents. The air quality in this conurbation is heavily influenced by urbanization; however, there are no comprehensive studies evaluating the sources of air pollution and their health impacts. Despite their proximity, the substantial variation in altitude, topography, and socioeconomic activities between La Paz and El Alto result in distinct sources, dynamics, and transport of particulate matter (PM). In this investigation, PM10 samples were collected at two urban background stations located in La Paz and El Alto between April 2016 and June 2017. The samples were later analyzed for a wide range of chemical species including numerous source tracers (OC, EC, water-soluble ions, sugar anhydrides, sugar alcohols, trace metals, and molecular organic species). The United States Environmental Protection Agency (U.S. EPA) Positive Matrix Factorization (PMF v.5.0) receptor model was employed for the source apportionment of PM10. This is one of the first source apportionment studies in South America that incorporates an extensive suite of organic markers, including levoglucosan, polycyclic aromatic hydrocarbons (PAHs), hopanes, and alkanes, alongside inorganic species. The multisite PMF resolved 11 main sources of PM. The largest annual contribution to PM10 came from the following two major sources: the ensemble of the four vehicular emissions sources (exhaust and non-exhaust), accountable for 35 % and 25 % of the measured PM in La Paz and El Alto, respectively; and dust, which contributed 20 % and 32 % to the total PM mass. Secondary aerosols accounted for 22 % (24 %) in La Paz (El Alto). Agricultural smoke resulting from biomass burning in the Bolivian lowlands and neighboring countries contributed to 9 % (8 %) of the total PM10 mass annually, increasing to 17 % (13 %) between August–October. Primary biogenic emissions were responsible for 13 % (7 %) of the measured PM10 mass. Additionally, a profile associated with open waste burning occurring from May to August was identified. Although this source contributed only to 2 % (5 %) of the total PM10 mass, it constitutes the second largest source of PAHs, which are compounds potentially hazardous to human health. Our analysis additionally resolved two different traffic-related factors, a lubricant source (not frequently identified), and a non-exhaust emissions source. Overall, this study demonstrates that PM10 concentrations in La Paz and El Alto region are predominantly influenced by a limited number of local sources. In conclusion, to improve air quality in both cities, efforts should primarily focus on addressing dust, traffic emissions, open waste burning, and biomass burning.
Ključne besede: source apportionment, particular air pollution, high altitude, positive matrix factorization, PMF
Objavljeno v RUNG: 15.09.2023; Ogledov: 799; Prenosov: 5
Celotno besedilo (3,55 MB)
Gradivo ima več datotek! Več... |
10. |
