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Fine particulate matter (PM) levels and resulting impacts on human health are in the Po Valley (Italy) among the highest in Europe. To build effective PM abatement strategies, it is necessary to characterize fine PM chemical composition, sources and atmospheric processes on long time scales (> months), with short time resolution (< day), and with particular emphasis on the predominant organic fraction. Although previous studies have been conducted in this region, none of them addressed all these aspects together. For the first time in the Po Valley, we investigate the chemical composition of non-refractory submicron PM (NR-PM1) with a time-resolution of 30 minutes at the regional background site of Ispra during one full year, using an Aerosol Chemical Speciation Monitor (ACSM) under the most up-to-date and stringent quality assurance protocol. The identification of the main components of the organic fraction is made using the Multilinear-Engine 2 algorithm implemented within the latest version of the SoFi toolkit. In addition, with a view of a potential implementation of ACSM measurements in European air quality networks as a replacement of traditional filter-based techniques, parallel multiple off-line analyses were carried out to assess the performance of the ACSM in the determination of PM chemical species regulated by Air Quality Directives. The annual NR-PM1 level monitored at the study site (14.2 µg/m³) is among the highest in Europe, and is even comparable to levels reported in urban areas like New York City (USA, 14.2 µg/m³) and Tokyo (Japan, 12-15 µg/m³). On the annual basis, submicron particles are primarily composed of organic aerosol (OA, 58% of NR-PM1). This fraction was apportioned into oxygenated OA (OOA, 66%), hydrocarbon-like OA (HOA, 11% of OA), and biomass burning OA (BBOA, 23%). Among the primary sources of OA, biomass burning (23%) is thus bigger than fossil fuel combustion (11%). Significant contributions of aged secondary organic aerosol (OOA) are observed throughout the year. The unexpectedly high degree of oxygenation estimated during wintertime is probably due to the contribution of secondary BBOA and the enhancement of aqueous phase production of OOA during cold months. BBOA and nitrate are the only components of which contributions increase with the NR-PM1 levels. Therefore, biomass burning and NOx emission reductions would be particularly efficient in limiting submicron aerosol pollution events. Abatement strategies conducted during cold seasons appear to be more efficient than annual-based policies. In a broader context, further studies using high-time resolution analytical techniques on a long-term basis for the characterization of fine aerosol should help better shape our future air quality policies, which constantly need refinement. [ABSTRACT FROM AUTHOR]

As part of the European ACTRIS project, the first large Quadrupole Aerosol Chemical Speciation Monitor (QACSM) intercomparison study was conducted in the region of Paris for 3 weeks during the late-fall - early-winter period (November-December 2013). The first week was dedicated to the tuning and calibration of each instrument, whereas the second and third were dedicated to side-by-side comparison in ambient conditions with co-located instruments providing independent information on submicron aerosol optical, physical, and chemical properties. Near real-time measurements of the major chemical species (organic matter, sulfate, nitrate, ammonium, and chloride) in the non-refractory submicron aerosols (NR-PM1/ were obtained here from 13 QACSM. The results show that these instruments can produce highly comparable and robust measurements of the NR-PM1 total mass and its major components. Taking the median of the 13 Q-ACSM as a reference for this study, strong correlations (r² > 0:9) were observed systematically for each individual Q-ACSM across all chemical families except for chloride for which three Q-ACSMs showing weak correlations partly due to the very low concentrations during the study. Reproducibility expanded uncertainties of Q-ACSM concentration measurements were determined using appropriate methodologies defined by the International Standard Organization (ISO 17025, 1999) and were found to be 9, 15, 19, 28, and 36% for NR-PM1, nitrate, organic matter, sulfate, and ammonium, respectively. However, discrepancies were observed in the relative concentrations of the constituent mass fragments for each chemical component. In particular, significant differences were observed for the organic fragment at mass-to-charge ratio 44, which is a key parameter describing the oxidation state of organic aerosol. Following this first major intercomparison exercise of a large number of Q-ACSMs, detailed intercomparison results are presented, along with a discussion of some recommendations about best calibration practices, standardized data processing, and data treatment. [ABSTRACT FROM AUTHOR]

Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSMs) performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM) from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM), and one high-resolution ToF aerosol mass spectrometer (AMS) were operated in parallel for about 3 weeks in November and December 2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF) utilising the multilinear engine 2 (ME-2). Except for the organic contribution of mass-to-charge ratio m/z 44 to the total organics (f44), which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA), cooking-related organic aerosol (COA), biomass burning-related organic aerosol (BBOA) and secondary oxygenated organic aerosol (OOA). ME-2 boundary conditions (profile constraints) were optimised individually by means of correlation to external data in order to achieve equivalent / comparable solutions for all ACSM instruments and the results are discussed together with the investigation of the influence of alternative anchors (reference profiles). A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative standard deviations (SD) from the mean between 13.7 and 22.7% of the source's average mass contribution depending on the factors (HOA: 14.3 º 2.2 %, COA: 15.0 º 3.4 %, OOA: 41.5 º 5.7 %, BBOA: 29.3 º 5.0 %). Factors which tend to be subject to minor factor mixing (in this case COA) have higher relative uncertainties than factors which are recognised more readily like the OOA. Averaged over all factors and instruments the relative first SD from the mean of a source extracted with ME-2 was 17.2 %. [ABSTRACT FROM AUTHOR]

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 µmp<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 4.7m² g-1 at 637 nm. Carbon aerosol sources were identified by PositiveMatrix 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. [ABSTRACT FROM AUTHOR]

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 < 2.5µm) and coarse (2.5µm < Dp < 10µm) 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. [ABSTRACT FROM AUTHOR]

The WB Green Agenda (WB GA) aims to implement the GD principles in this region and has defined five priority areas: climate, energy, mobility; circular economy, pollution reduction, sustainable agricultural and food production, and biodiversity. Some of the WB GA goals are strongly related to health: e.g. the continent’s carbon neutrality by 2050, the ambitious climate policy, the reform of energy and transport sectors. The launch of the EU CP is an important opportunity for the WB to promote action in this area. For instance, promoting energy efficiency and supporting building renovation are directly related to the quality of life and hygiene of housing. Reduction or cancellation of coal subsidies as well as the region’s withdrawal from the use of coal is of great importance for reducing externalities. In the WB, citizens are concerned about their health due to air, water and soil pollution and their reduction is in the common interest. To that end, it is necessary, inter alia, to: ratify the Convention on Long-range Transboundary Air Pollution and its protocols in each of the WB economies; to implement air quality strategies; and to strengthen air quality monitoring systems (and network accreditation). Appropriate processes are needed to reduce water and soil pollution, as well as to ensure the transformation of the agricultural sector. It is also necessary to harmonize the agricultural and food sector with EU standards for food safety, plant and animal health and environmental protection. To achieve the WB GA goals it is important to develop policy strategies based on the most up-to-date scientific studies for this region (JRC, 2020). On the basis of the analysis presented in this study we conclude that the processes associated with the GD and the CP will be of benefit for both individual and public health in the EU and in the WB. [ABSTRACT FROM AUTHOR]

A fine resolution study on fossil ostracods in late glacial sediments from Lago di Albano was performed within the framework of the European project PALICLAS. Four cores from two coring sites were analysed.At Site 1, located at 70 m depth, cores PALB94 1E and PALB94 1C werecollected, while cores PALB94 6A and PALB94 6B were collected at Site 6 at 30 m depth. The autoecology of the ostracod species, cluster analysis, PCA and CA ordination numerical analyses were performed in order to identify changes in environmental conditions within the sedimentary record. Three assemblages were recognized: (a) dominated by C.neglecta representing sublittoral environments, (b) dominated by C. neglecta accompanied by Potamocypris spp. related to spring influx and (c) dominated by Cyclocypris sp. associated with littoral and relatively warmer conditions.A reconstruction of lake water level, oxygen concentration near the bottom and lake productivity, based on ostracod autoecology and supported by fossil pigment data, was accomplished.Sharp fluctuations in water level and productivity seem to indicate climatic oscillations between ca 30 to ca 17 kyr BP. [ABSTRACT FROM AUTHOR]