scholarly journals Trends, composition, and sources of carbonaceous aerosol in the last 18 years at the Birkenes Observatory, Northern Europe

2020 ◽  
Author(s):  
Karl Espen Yttri ◽  
Francesco Canonaco ◽  
Sabine Eckhardt ◽  
Nikolaos Evangeliou ◽  
Markus Fiebig ◽  
...  
Keyword(s):  
Elemental Carbon ◽  
Organic Aerosol ◽  
Carbonaceous Aerosol ◽  
Low Carbon ◽  
Positive Matrix ◽  
Northern European ◽  
Aerosol Sources ◽  
Southern Norway ◽  
A Site ◽  
Biological Aerosol Particles

Abstract. We present 18 years (2001–2018) of aerosol measurements: organic- and elemental carbon (OC and EC), organic tracers (levoglucosan, arabitol, mannitol, trehalose, glucose, 2-methyltetrols), trace elements and ions – at the Birkenes Observatory (Southern Norway), a site representative of the Northern European region. The OC / EC (2001–2018) and the levoglucosan (2008–2018) time series are the longest in Europe, with OC / EC available for the PM10, PM2.5 (fine) and PM10-2.5 (coarse) size fractions, providing the opportunity for a nearly two-decade long assessment. Using positive matrix factorisation (PMF) we identify six carbonaceous aerosol sources at Birkenes: Mineral dust dominated (MIN), traffic/industry-like (TRA/IND), short range transported biogenic secondary organic aerosol (BSOASRT), primary biological aerosol particles (PBAP), biomass burning (BB), and ammonium nitrate dominated (NH4NO3), and one low carbon fraction, sea salt (SS). We observed significant (p 

scholarly journals Sources of carbonaceous aerosol in the Amazon Basin

2010 ◽  
Vol 10 (12) ◽  
pp. 29923-29969 ◽  
Author(s):  
S. Gilardoni ◽  
E. Vignati ◽  
E. Marmer ◽  
F. Cavalli ◽  
C. Belis ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Amazon Basin ◽  
Elemental Carbon ◽  
Aerosol Particles ◽  
Dry Season ◽  
Carbonaceous Aerosol ◽  
Wet Season ◽  
Aerosol Mass ◽  
Aerosol Sources ◽  
Coarse Aerosol

Abstract. The quantification of sources of carbonaceous aerosol is important to understand their atmospheric concentrations and regulating processes and to study possible effects on climate and air quality, in addition to develop mitigation strategies. In the framework of the European Aerosol Cloud Climate Interaction (EUCAARI) project fine (Dp < 2.5 μm) and coarse (2.5 μm < Dp < 10 μm) aerosol particles were sampled from February to June (wet season) and from August to September (dry season) 2008 in the Central Amazon Basin. The mass of fine particles averaged 2.4 μg m−3 during the wet season and 4.2 μg m−3 during the dry season. The average coarse aerosol mass concentration during wet and dry periods was 7.9 and 7.6 μg m−3, respectively. The overall chemical composition of fine and coarse mass did not show any seasonality with the largest fraction of fine and coarse aerosol mass explained by organic carbon (OC); the average OC to mass ratio was 0.4 and 0.6 in fine and coarse aerosol modes, respectively. The mass absorbing cross section of soot was determined by comparison of elemental carbon and light absorption coefficient measurements and it was equal to 4.7 m2 g−1 at 637 nm. Carbon aerosol sources were identified by Positive Matrix Factorization (PMF) analysis of thermograms: 43% of fine total carbon mass was assigned to biomass burning, 34% to secondary organic aerosol (SOA), and 23% to volatile species that are difficult to apportion. In the coarse mode, primary biogenic aerosol particles (PBAP) dominated the carbonaceous aerosol mass. The results confirmed the importance of PBAP in forested areas. The source apportionment results were employed to evaluate the ability of global chemistry transport models to simulate carbonaceous aerosol sources in a regional tropical background site. The comparison showed an overestimation of elemental carbon (EC) by the TM5 model during the dry season and OC both during the dry and wet periods. The overestimation was likely due to the overestimation of biomass burning emission inventories and SOA production over tropical areas.

scholarly journals Sources of carbonaceous aerosol in the Amazon basin

2011 ◽  
Vol 11 (6) ◽  
pp. 2747-2764 ◽  
Author(s):  
S. Gilardoni ◽  
E. Vignati ◽  
E. Marmer ◽  
F. Cavalli ◽  
C. Belis ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Amazon Basin ◽  
Elemental Carbon ◽  
Aerosol Particles ◽  
Dry Season ◽  
Carbonaceous Aerosol ◽  
Wet Season ◽  
Aerosol Mass ◽  
Aerosol Sources ◽  
Coarse Aerosol

Abstract. The quantification of sources of carbonaceous aerosol is important to understand their atmospheric concentrations and regulating processes and to study possible effects on climate and air quality, in addition to develop mitigation strategies. In the framework of the European Integrated Project on Aerosol Cloud Climate Interactions (EUCAARI) fine (Dp < 2.5 μm) and coarse (2.5 μm < Dp <10 μm) aerosol particles were sampled from February to June (wet season) and from August to September (dry season) 2008 in the central Amazon basin. The mass of fine particles averaged 2.4 μg m−3 during the wet season and 4.2 μg m−3 during the dry season. The average coarse aerosol mass concentration during wet and dry periods was 7.9 and 7.6 μg m−3, respectively. The overall chemical composition of fine and coarse mass did not show any seasonality with the largest fraction of fine and coarse aerosol mass explained by organic carbon (OC); the average OC to mass ratio was 0.4 and 0.6 in fine and coarse aerosol modes, respectively. The mass absorbing cross section of soot was determined by comparison of elemental carbon and light absorption coefficient measurements and it was equal to 4.7 m2 g−1 at 637 nm. Carbon aerosol sources were identified by Positive Matrix Factorization (PMF) analysis of thermograms: 44% of fine total carbon mass was assigned to biomass burning, 43% to secondary organic aerosol (SOA), and 13% to volatile species that are difficult to apportion. In the coarse mode, primary biogenic aerosol particles (PBAP) dominated the carbonaceous aerosol mass. The results confirmed the importance of PBAP in forested areas. The source apportionment results were employed to evaluate the ability of global chemistry transport models to simulate carbonaceous aerosol sources in a regional tropical background site. The comparison showed an overestimation of elemental carbon (EC) by the TM5 model during the dry season and OC both during the dry and wet periods. The overestimation was likely due to the overestimation of biomass burning emission inventories and SOA production over tropical areas.

scholarly journals Trends, composition, and sources of carbonaceous aerosol at the Birkenes Observatory, northern Europe, 2001–2018

2021 ◽  
Vol 21 (9) ◽  
pp. 7149-7170
Author(s):  
Karl Espen Yttri ◽  
Francesco Canonaco ◽  
Sabine Eckhardt ◽  
Nikolaos Evangeliou ◽  
Markus Fiebig ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Fossil Fuel ◽  
Coarse Fraction ◽  
Relative Increase ◽  
Carbonaceous Aerosol ◽  
Anthropogenic Sources ◽  
Low Carbon ◽  
Aerosol Composition ◽  
Model Calculations ◽  
Aerosol Sources

Abstract. We present 18 years (2001–2018) of aerosol measurements, including organic and elemental carbon (OC and EC), organic tracers (levoglucosan, arabitol, mannitol, trehalose, glucose, and 2-methyltetrols), trace elements, and ions, at the Birkenes Observatory (southern Norway) – a site representative of the northern European region. The OC/EC (2001–2018) and the levoglucosan (2008–2018) time series are the longest in Europe, with OC/EC available for the PM10, PM2.5 (fine), and PM10–2.5 (coarse) size fractions, providing the opportunity for a nearly 2-decade-long assessment. Using positive matrix factorization (PMF), we identify seven carbonaceous aerosol sources at Birkenes: mineral-dust-dominated aerosol (MIN), traffic/industry-like aerosol (TRA/IND), short-range-transported biogenic secondary organic aerosol (BSOASRT), primary biological aerosol particles (PBAP), biomass burning aerosol (BB), ammonium-nitrate-dominated aerosol (NH4NO3), and (one low carbon fraction) sea salt aerosol (SS). We observed significant (p<0.05), large decreases in EC in PM10 (−3.9 % yr−1) and PM2.5 (−4.2 % yr−1) and a smaller decline in levoglucosan (−2.8 % yr−1), suggesting that OC/EC from traffic and industry is decreasing, whereas the abatement of OC/EC from biomass burning has been slightly less successful. EC abatement with respect to anthropogenic sources is further supported by decreasing EC fractions in PM2.5 (−3.9 % yr−1) and PM10 (−4.5 % yr−1). PMF apportioned 72 % of EC to fossil fuel sources; this was further supported by PMF applied to absorption photometer data, which yielded a two-factor solution with a low aerosol Ångstrøm exponent (AAE = 0.93) fraction, assumed to be equivalent black carbon from fossil fuel combustion (eBCFF), contributing 78 % to eBC mass. The higher AAE fraction (AAE = 2.04) is likely eBC from BB (eBCBB). Source–receptor model calculations (FLEXPART) showed that continental Europe and western Russia were the main source regions of both elevated eBCBB and eBCFF. Dominating biogenic sources explain why there was no downward trend for OC. A relative increase in the OC fraction in PM2.5 (+3.2 % yr−1) and PM10 (+2.4 % yr−1) underscores the importance of biogenic sources at Birkenes (BSOA and PBAP), which were higher in the vegetative season and dominated both fine (53 %) and coarse (78 %) OC. Furthermore, 77 %–91 % of OC in PM2.5, PM10–2.5, and PM10 was attributed to biogenic sources in summer vs. 22 %–37 % in winter. The coarse fraction had the highest share of biogenic sources regardless of season and was dominated by PBAP, except in winter. Our results show a shift in the aerosol composition at Birkenes and, thus, also in the relative source contributions. The need for diverse offline and online carbonaceous aerosol speciation to understand carbonaceous aerosol sources, including their seasonal, annual, and long-term variability, has been demonstrated.

scholarly journals Development of a versatile source apportionment analysis based on positive matrix factorization: a case study of the seasonal variation of organic aerosol sources in Estonia

2019 ◽  
Vol 19 (11) ◽  
pp. 7279-7295 ◽  
Author(s):  
Athanasia Vlachou ◽  
Anna Tobler ◽  
Houssni Lamkaddam ◽  
Francesco Canonaco ◽  
Kaspar R. Daellenbach ◽  
...  
Keyword(s):  
Matrix Factorization ◽  
Organic Aerosol ◽  
Positive Matrix Factorization ◽  
Water Soluble ◽  
Oxidation Products ◽  
Positive Matrix ◽  
Bootstrap Analysis ◽  
Seasonal Behavior ◽  
Yearly Cycle ◽  
Aerosol Mass

Abstract. Bootstrap analysis is commonly used to capture the uncertainties of a bilinear receptor model such as the positive matrix factorization (PMF) model. This approach can estimate the factor-related uncertainties and partially assess the rotational ambiguity of the model. The selection of the environmentally plausible solutions, though, can be challenging, and a systematic approach to identify and sort the factors is needed. For this, comparison of the factors between each bootstrap run and the initial PMF output, as well as with externally determined markers, is crucial. As a result, certain solutions that exhibit suboptimal factor separation should be discarded. The retained solutions would then be used to test the robustness of the PMF output. Meanwhile, analysis of filter samples with the Aerodyne aerosol mass spectrometer and the application of PMF and bootstrap analysis on the bulk water-soluble organic aerosol mass spectra have provided insight into the source identification and their uncertainties. Here, we investigated a full yearly cycle of the sources of organic aerosol (OA) at three sites in Estonia: Tallinn (urban), Tartu (suburban) and Kohtla-Järve (KJ; industrial). We identified six OA sources and an inorganic dust factor. The primary OA types included biomass burning, dominant in winter in Tartu and accounting for 73 % ± 21 % of the total OA, primary biological OA which was abundant in Tartu and Tallinn in spring (21 % ± 8 % and 11 % ± 5 %, respectively), and two other primary OA types lower in mass. A sulfur-containing OA was related to road dust and tire abrasion which exhibited a rather stable yearly cycle, and an oil OA was connected to the oil shale industries in KJ prevailing at this site that comprises 36 % ± 14 % of the total OA in spring. The secondary OA sources were separated based on their seasonal behavior: a winter oxygenated OA dominated in winter (36 % ± 14 % for KJ, 25 % ± 9 % for Tallinn and 13 % ± 5 % for Tartu) and was correlated with benzoic and phthalic acid, implying an anthropogenic origin. A summer oxygenated OA was the main source of OA in summer at all sites (26 % ± 5 % in KJ, 41 % ± 7 % in Tallinn and 35 % ± 7 % in Tartu) and exhibited high correlations with oxidation products of a-pinene-like pinic acid and 3-methyl-1, 2, 3-butanetricarboxylic acid (MBTCA), suggesting a biogenic origin.

scholarly journals Fog scavenging of organic and inorganic aerosol in the Po Valley

2014 ◽  
Vol 14 (4) ◽  
pp. 4787-4826 ◽  
Author(s):  
S. Gilardoni ◽  
P. Massoli ◽  
L. Giulianelli ◽  
M. Rinaldi ◽  
M. Paglione ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Black Carbon ◽  
Functional Group ◽  
Group Composition ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Carbonaceous Aerosol ◽  
Model Description ◽  
Po Valley ◽  
Scavenging Efficiency

Abstract. The interaction of aerosol with atmospheric water affects the processing and wet removal of atmospheric particles. Understanding such interaction is mandatory to improve model description of aerosol lifetime and ageing. We analyzed the aerosol-water interaction at high relative humidity during fog events in the Po Valley, in the framework of the ARPA-ER Supersite project. For the first time in this area, the changes in particle chemical composition caused by fog are discussed along with changes in particle microphysics. During the experiment, 14 fog events were observed. The average mass scavenging efficiency was 70% for nitrate, 68% for ammonium, 61% for sulfate, 50% for organics, and 39% for black carbon. After fog formation, the interstitial aerosol was dominated by particles smaller than 200 nm Dva (vacuum aerodynamic diameter) and enriched in carbonaceous aerosol, mainly black carbon and water insoluble organic aerosol (WIOA). For each fog event, the size segregated scavenging efficiency of nitrate and organic aerosol (OA) was calculated by comparing chemical species size distribution before and after fog formation. For both nitrate and OA, the size segregated scavenging efficiency followed a sigmoidal curve, with values close to zero below 100 nm Dva and close to 1 above 700 nm Dva. OA was able to affect scavenging efficiency of nitrate in particles smaller than 300 nm Dva. A linear correlation between nitrate scavenging and particle hygroscopicity (κ) was observed, indicating that 44–51% of the variability of nitrate scavenging in smaller particles (below 300 nm Dva) was explained by changes in particle chemical composition. The size segregated scavenging curves of OA followed those of nitrate, suggesting that organic scavenging was controlled by mixing with water-soluble species. In particular, functional group composition and OA elemental analysis indicated that more oxidized OA was scavenged more efficiently than less oxidized OA. Nevertheless, the small variability of organic functional group composition during the experiment did not allow us to discriminate the effect of different organic functionalities on OA scavenging.

scholarly journals Evolution of volatility and composition in sesquiterpene-mixed and α-pinene secondary organic aerosol particles during isothermal evaporation

2021 ◽  
Author(s):  
Zijun Li ◽  
Angela Buchholz ◽  
Arttu Ylisirniö ◽  
Luis Barreira ◽  
Liqing Hao ◽  
...  
Keyword(s):  
Aqueous Phase ◽  
Volume Fraction ◽  
Organic Aerosol ◽  
Single Type ◽  
Positive Matrix ◽  
Evaporation Time ◽  
Multiple Processes ◽  
Isothermal Evaporation ◽  
Dry Conditions

Abstract. Efforts have been spent on investigating the isothermal evaporation of α-pinene SOA particles at ranges of conditions and decoupling the impacts of viscosity and volatility on evaporation. However, little is known about the evaporation behavior of SOA particles from biogenic organic compounds other than α-pinene. In this study, we investigated the isothermal evaporation behaviors of α-pinene (αpin) and sesquiterpene mixture (SQTmix) SOA particles under a series of relative humidity (RH) conditions. With a set of in-situ instruments, we monitored the evolution of particle size, volatility, and composition during evaporation. Our finding demonstrates that the SQTmix SOA particles evaporated slower than the αpin ones at any set of RH (expressed with the volume fraction remaining (VFR)), which is primarily due to their lower volatility and possibly aided by higher viscosity under dry conditions. We further applied positive matrix factorization (PMF) to thermal desorption data containing volatility and composition information. Analyzing the net change ratios (NCRs) of each PMF-resolved factor, we can quantitatively compare how each sample factor evolves with increasing evaporation time/RH. When sufficient particulate water content was present in either SOA system, the most volatile sample factor was primarily lost via evaporation and changes in other sample factors were mainly governed by aqueous-phase processes. The evolution of each sample factor of SQTmix SOA particles was controlled by a single type of process, whereas for αpin SOA particles it was regulated by multiple processes. As indicated by the coevolution of VFR and NCR, the effect of aqueous-phase processes could vary from one to another according to particle type, sample factors and evaporation timescale.

scholarly journals High contributions of fossil sources to more volatile organic aerosol

2019 ◽  
Vol 19 (15) ◽  
pp. 10405-10422 ◽  
Author(s):  
Haiyan Ni ◽  
Ru-Jin Huang ◽  
Junji Cao ◽  
Wenting Dai ◽  
Jiamao Zhou ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Elemental Carbon ◽  
Organic Aerosol ◽  
Formation Mechanisms ◽  
Formation Processes ◽  
Combustion System ◽  
Relative Contribution ◽  
Custom Made ◽  
Volatile Organic ◽  
Volatile Carbon

Abstract. Sources of particulate organic carbon (OC) with different volatility have rarely been investigated, despite the significant importance for better understanding of the atmospheric processes of organic aerosols. In this study we develop a radiocarbon-based (14C) approach for source apportionment of more volatile OC (mvOC) and apply to ambient aerosol samples collected in winter in six Chinese megacities. mvOC is isolated by desorbing organic carbon from the filter samples in helium (He) at 200 ∘C in a custom-made aerosol combustion system for 14C analysis. Evaluation of this new isolation method shows that the isolated mvOC amount agrees very well with the OC1 fraction (also desorbed at 200 ∘C in He) measured by a thermal–optical analyzer using the EUSAAR_2 protocol. The mvOC, OC and elemental carbon (EC) of 13 combined PM2.5 samples in six Chinese cities are analyzed for 14C to investigate their sources and formation mechanisms. The relative contribution of fossil sources to mvOC is 59±11 %, consistently larger than the contribution to OC (48±16 %) and smaller than that to EC (73±9 %), despite large differences in fossil contributions in different cities. The average difference in the fossil fractions between mvOC and OC is 13 % (range of 7 %–25 %), similar to that between mvOC and EC (13 %, with a range 4 %–25 %). Secondary OC (SOC) concentrations and sources are modeled based on the 14C-apportioned OC and EC and compared with concentrations and sources of mvOC. SOC concentrations (15.4±9.0 µg m−3) are consistently higher than those of mvOC (3.3±2.2 µg m−3), indicating that only a fraction of SOC is accounted for by the more volatile carbon fraction desorbed at 200 ∘C. The fossil fraction in SOC is 43 % (10 %–70 %), lower than that in mvOC (59 %, with a range of 45 %–78 %). Correlation between mvOC and SOC from nonfossil sources (mvOCnf vs. SOCnf) and from fossil sources (mvOCfossil vs. SOCfossil) is examined to further explore sources and formation processes of mvOC and SOC.

Sign in / Sign up

Export Citation Format

Share Document