@article{Boose2016, abstract = {Abstract. This study aims at quantifying the ice nucleation properties of desert dust in the Saharan Air Layer (SAL), the warm, dry and dust-laden layer that expands from North Africa to the Americas. By measuring close to the dust's emission source, before aging processes during the transatlantic advection potentially modify the dust properties, the study fills a gap between in situ measurements of dust ice nucleating particles (INPs) far away from the Sahara and laboratory studies of ground-collected soil. Two months of online INP concentration measurements are presented, which were part of the two CALIMA campaigns at the Izaña observatory in Tenerife, Spain (2373 m a.s.l.), in the summers of 2013 and 2014. INP concentrations were measured in the deposition and condensation mode at temperatures between 233 and 253 K with the Portable Ice Nucleation Chamber (PINC). Additional aerosol information such as bulk chemical composition, concentration of fluorescent biological particles as well as the particle size distribution was used to investigate observed variations in the INP concentration. The concentration of INPs was found to range between 0.2 std L−1 in the deposition mode and up to 2500 std L−1 in the condensation mode at 240 K. It correlates well with the abundance of aluminum, iron, magnesium and manganese (R: 0.43–0.67) and less with that of calcium, sodium or carbonate. These observations are consistent with earlier results from laboratory studies which showed a higher ice nucleation efficiency of certain feldspar and clay minerals compared to other types of mineral dust. We find that an increase of ammonium sulfate, linked to anthropogenic emissions in upwind distant anthropogenic sources, mixed with the desert dust has a small positive effect on the condensation mode INP per dust mass ratio but no effect on the deposition mode INP. Furthermore, the relative abundance of biological particles was found to be significantly higher in INPs compared to the ambient aerosol. Overall, this suggests that atmospheric aging processes in the SAL can lead to an increase in ice nucleation ability of mineral dust from the Sahara. INP concentrations predicted with two common parameterization schemes, which were derived mostly from atmospheric measurements far away from the Sahara but influenced by Asian and Saharan dust, were found to be higher based on the aerosol load than we observed in the SAL, further suggesting aging effects of INPs in the SAL. }, author = {Boose, Yvonne and Sierau, Berko and García, M. Isabel and Rodríguez, Sergio and Alastuey, Andrés and Linke, Claudia and Schnaiter, Martin and Kupiszewski, Piotr and Kanji, Zamin A. and Lohmann, Ulrike}, doi = {10.5194/acp-16-9067-2016}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {mar}, pages = {1-36}, title = {Ice nucleating particles in the Saharan Air Layer}, url = {https://doi.org/10.5194/acp-16-9067-2016}, volume = {16}, year = {2016} } @article{Castillo2004, author = {Castillo, S. and Alastuey, A. and Querol, X. and Garcia, O. and Romero, P. M. and Cuevas, E. and Díaz, J. P. and Expósito, F. J. and Avila, A.}, doi = {10.1016/s0021-8502(19)30262-9}, journal = {Journal of Aerosol Science}, month = {jan}, pages = {S1055-S1056}, title = {Characterisation of ambient air PM during African outbreaks over Northeastern Iberian Peninsula and the Canary Islands}, url = {https://oadoi.org/10.1016/s0021-8502(19)30262-9}, volume = {35}, year = {2004} } @article{Cazorla2017, abstract = {The interest on the use of ceilometers for optical aerosol characterization has increased in the last few years. They operate continuously almost unattended and are also much less expensive than lidars, hence they can be distributed in dense networks over large areas. However, due to the low signal-to-noise-ratio it is not always possible to obtain particle 20 backscatter coefficient profiles, and the vast amount of data generated requires an automated and unsupervised method that ensures the quality of the profiles inversions. In this work a method that uses aerosol optical depth (AOD) measurements from the AERONET network is applied for the calibration and automated quality assurance of inversion of ceilometer profiles. The method is compared with Independent inversions obtained by co-located multiwavelength lidar measurements and a difference up to 15% in backscatter is found 25 between both instruments. This method is continuously and automatically applied to the Iberian Ceilometer Network (ICENET) and a case example during an unusually intense dust outbreak affecting the Iberian Peninsula on 20 February 2016 and lasted until 24 February 2016 is shown. Results reveal that it is possible to obtain a quantitative optical Aerosol characterization (particle backscatter coefficient) with ceilometers over large areas and this information has a great potential for alert systems and model assimilation and evaluation.}, author = {Cazorla, Alberto and Casquero-Vera, Juan Andrés and Román, Roberto and Guerrero-Rascado, Juan Luis and Toledano, Carlos and Cachorro, Victoria E. and Orza, José Antonio G. and Cancillo, María Luisa and Serrano, Antonio and Titos, Gloria and Pandolfi, Marco and Alastuey, Andrés and Hanrieder, Natalie and Alados-Arboledas, Lucas}, doi = {10.5194/acp-2017-151}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {apr}, pages = {1-28}, title = {Near real time processing of ceilometer network data: characterizing an extraordinary dust outbreak over the Iberian Peninsula}, url = {https://doi.org/10.5194/acp-2017-151}, year = {2017} } @article{Dall&apos;Osto2013, abstract = {Abstract. Sources and evolution of ultrafine particles were investigated both horizontally and vertically in the large urban agglomerate of Barcelona, Spain. Within the SAPUSS project (Solving Aerosol Problems by Using Synergistic Strategies), a large number of instruments was deployed simultaneously at different monitoring sites (road, two urban background, regional background, urban tower 150 m a.s.l., urban background tower site 80 m a.s.l.) during a 4 week period in September–October 2010. Particle number concentrations (N>5 nm) are highly correlated with black carbon (BC) at all sites only under strong vehicular traffic influences. By contrast, under cleaner atmospheric conditions (low condensation sink, CS) such correlation diverges towards much higher N/BC ratios at all sites, indicating additional sources of particles including secondary production of freshly nucleated particles. Size-resolved aerosol distributions (N10–500) as well as particle number concentrations (N>5 nm) allow us to identify three types of nucleation and growth events: (1) a regional type event originating in the whole study region and impacting almost simultaneously the urban city of Barcelona and the surrounding urban background area; (2) a regional type event impacting only the regional background area but not the urban agglomerate; (3) an urban type event which originates only within the city centre but whose growth continues while transported away from the city to the regional background. Furthermore, during these clean air days, higher N are found at tower level than at ground level only in the city centre whereas such a difference is not so pronounced at the remote urban background tower. In other words, this study suggests that the column of air above the city ground level possesses the optimal combination between low CS and high vapour source, hence enhancing the concentrations of freshly nucleated particles. By contrast, within stagnant polluted atmospheric conditions, higher N and BC concentrations are always measured at ground level relative to tower level at all sites. Our study suggests that the city centre of Barcelona is a source of non-volatile traffic primary particles (29–39% of N>5 nm), but other sources, including secondary freshly nucleated particles contribute up to 61–71% of particle number (N>5 nm) at all sites. We suggest that organic compounds evaporating from freshly emitted traffic particles are a possible candidate for new particle formation within the city and urban plume. }, author = {Dall&apos;Osto, M. and Dall'Osto, M. and Querol, X. and Alastuey, A. and O&apos;Dowd, C. and O'Dowd, C. and Harrison, R. M. and Wenger, J. and Gómez Moreno, F. J.}, doi = {10.5194/acp-13-741-2013}, journal = {Atmospheric Chemistry and Physics}, month = {jan}, pages = {741-759}, title = {On the spatial distribution and evolution of ultrafine particles in Barcelona}, url = {http://dx.doi.org/10.5194/acp-13-741-2013}, volume = {13}, year = {2013} } @article{Diapouli2016, author = {Diapouli, Evangelia and Manousakas, Manousos I. and Vratolis, Stergios and Vasilatou, Vasiliki and Pateraki, Stella and Bairachtari, Kyriaki A. and Querol, Xavier and Amato, Fulvio and Alastuey, Andrés and Karanasiou, Angeliki A. and Lucarelli, Franco and Nava, Silvia and Calzolai, Giulia and Gianelle, Vorne L. and Colombi, Cristina and Alves, Célia and Custódio, Danilo and Pio, Casimiro and Spyrou, Chris and Kallos, George B. and Eleftheriadis, Konstantinos}, doi = {10.5194/acp-2016-781}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {sep}, pages = {1-25}, title = {AIRUSE-LIFE&thinsp;+: Estimation of natural source contributions to urban ambient air PM<sub>10</sub> and PM<sub>2.5</sub> concentrations in Southern Europe. Implications to compliance with limit values}, url = {https://doi.org/10.5194/acp-2016-781}, year = {2016} } @article{Ealo2016, abstract = {The study of Saharan dust events (SDE) and biomass burning (BB) emissions are both topic of great scientific interest since they are frequent and important polluting scenarios affecting air quality and climate. The main aim of this work is evaluating the feasibility of using near real-time in situ aerosol optical measurements for the detection of these atmospheric events in the Western Mediterranean Basin (WMB). With this aim, intensive aerosol optical properties (SAE: scattering Ångström exponent, AAE: absorption Ångström exponent, SSAAE: single scattering albedo Ångström exponent, and g: asymmetry parameter) were derived from multi-wavelength aerosol light scattering, hemispheric backscattering and absorption measurements performed at regional (Montseny; MSY, 720 m a.s.l.) and continental (Montsec; MSA, 1570 m a.s.l.) background sites in the WMB. A sensitivity study aiming at calibrating the measured intensive optical properties for SDE and BB detection is presented and discussed. The detection of Saharan dust events (SDE) by means of the SSAAE parameter and Ångström matrix depended on the altitude of the measurement station, and on SDE intensity. At MSA (mountain-top site) SSAAE detected around 85% of SDE compared with 50% at MSY station, where pollution episodes dominated by fine anthropogenic particles frequently masked the effect of mineral dust on optical properties during less intense SDE. Furthermore, an interesting feature of SSAAE was its capability to detect the presence of mineral dust after the end of SDE. Thus, resuspension processes driven by summer regional atmospheric circulations and dry conditions after SDE favored the accumulation of mineral dust at regional level having important consequences for air quality. On average, SAE, AAE and g ranged between -0.7 and 1, 1.3 and 2.5, and 0.5 and 0.75, respectively, during SDE. Based on the Aethalometer model, biomass burning (BB) contribution to equivalent black carbon (BC) accounted for 36% and 40% at MSY and MSA respectively. Linear relationships were found between AAE and %BCbb, with AAE values reaching around 1.5 when %BCbb was higher than 50%. BB contribution to organic matter (OM) at MSY was around 30%. Thus FF combustion sources showed important contributions to both BC and OM in the region under study. Results for OM source apportionment showed good agreement with simultaneous biomass burning organic aerosol (BBOA) and hydrocarbon-like organic aerosol (HOA) calculated from Positive Matrix Factorization (PMF) applied to simultaneous Aerosol Mass Spectrometer (ACSM) measurements. A wildfire episode was identified at MSY, showing AAE values up to 2 when daily BB contributions to BC and OM were 73% and 78% respectively.}, author = {Ealo, M. and Alastuey, A. and Ripoll, A. and Pérez, N. and Minguillón, M. C. and Querol, X. and Pandolfi, M.}, doi = {10.5194/acp-2015-902}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {jan}, pages = {1-32}, title = {Detection of Saharan dust and biomass burning events using near real-time intensive aerosol optical properties in the northwestern Mediterranean}, url = {https://doi.org/10.5194/acp-2015-902}, year = {2016} } @article{Ealo2017, author = {Ealo, Marina and Alastuey, Andrés and Pérez, Noemí and Ripoll, Anna and Querol, Xavier and Pandolfi, Marco}, doi = {10.5194/acp-2017-217}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {apr}, pages = {1-43}, title = {From air quality to climate: Impact of aerosol sources on optical properties at urban, regional and continental levels in the north-western Mediterranean}, url = {https://doi.org/10.5194/acp-2017-217}, year = {2017} } @article{Fonseca2016, abstract = {Due to the need to better characterise the ultrafine particles fraction and related personal exposure, several impactors have been developed to enable the collection of ultrafine particles (<100 nm). However, to the authors’ kno wledge there have been no field campaigns to-date intercomparing impactor collection of ultrafine particles. The purpose of this study was two-fold: 1) to assess the performance of a number of conventional and nano-range cascade impactors with regard to the particle mass size distribution under different environmental conditions and aerosol loads and types, and 2) to characterise aerosol size distributions including ultrafine particles using impactors in 2 European locations. The impactors used were: (i) Berner low-pressure impactor (BLPI; 26 nm - 13.5 μm), (ii) nano-Berner low-pressure impactor (nano-BLPI; 11 nm - 1.95 μm) and (iii) Nano-microorifice uniform deposit impactor (nano-Moudi; 10 nm-18 μm), and (iv) Personal cascade impactor Sioutas (PCIS; <250 nm - 10 μm). Taking the BLPI as an internal reference, the best agreement regarding mass size distributions was obtained with the nano-BLPI, independently of the aerosol load and aerosol chemical composition. The nano-Moudi showed a good agreement for part icle sizes >320 nm, whereas for particle diameters <320 nm this instrument recorded larger mass concentrations in outdoor air than the internal reference. This difference could be due to particle bounce, to the dissociation of semi volatiles in the coarser stages and/or to particle shrinkage during transport through the impactor due to higher temperature inside this impactor. Further research is needed to understand this behaviour. With regard to the PCIS, their size-resolved mass concentrations were compar able with other impactors for PM1, PM2 and PM10, but the cut-off at 250 nm did not seem to be consistent with that of the internal reference.}, author = {Fonseca, A. S. and Talbot, N. and Schwarz, J. and Ondráček, J. and Ždímal, V. and Kozáková, J. and Viana, M. and Karanasiou, A. and Querol, X. and Alastuey, A. and Vu, T. V. and Delgado Saborit, J. M. and Harrison, R. M.}, doi = {10.5194/acp-2015-1016}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {jan}, pages = {1-27}, title = {Intercomparison of four different cascade impactors for fine and ultrafine particle sampling in two European locations}, url = {https://doi.org/10.5194/acp-2015-1016}, year = {2016} } @article{Fröhlich2015, abstract = {Abstract. 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 ± 2.2 %, COA: 15.0 ± 3.4 %, OOA: 41.5 ± 5.7 %, BBOA: 29.3 ± 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 %. }, author = {Fröhlich, Roman and Crenn, Vincent and Setyan, Ari and Belis, Claudio A. and Canonaco, Francesco and Favez, Olivier and Riffault, Véronique and Slowik, Jay G. and Aas, Wenche and Ca, Belis and Aijälä, Mikko and Alastuey, Andrés and Artiñano, B. and Artíaño, Begoña and Bonnaire, Nicolas and Bozzetti, Carlo and Bressi, Michaël and Carbone, Claudio and Coz, Esther and Croteau, Philip L. and Cubison, Michael J. and Esser Gietl, Johanna K. and Green, David C. and Gros, Valérie and Heikkinen, Liine and Herrmann, Hartmut and Jayne, John T. and Lunder, Chris Rene and Minguillón, María Cruz and Močnik, Griša and Jg, Slowik and O&apos;Dowd, C. D. and O'Dowd, Colin D. and Ovadnevaite, Jurgita and Petralia, Ettore and Poulain, Laurent and Priestman, Max and Ripoll, Anna and Sarda Estève, Roland and Wiedensohler, Alfred and Baltensperger, Urs and Sciare, Jean and Others, and Prévôt, André S. H.}, doi = {10.5194/amt-8-2555-2015}, journal = {Atmospheric Measurement Techniques Discussions}, month = {feb}, pages = {1559-1613}, title = {ACTRIS ACSM intercomparison - Part 2: Intercomparison of ME-2 organic source apportionment results from 15 individual, co-located aerosol mass spectrometers}, url = {https://doi.org/10.5194/amtd-8-1559-2015}, volume = {8}, year = {2015} } @article{Gomez-Moreno2004, author = {Gomez-Moreno, F. J. and Pujadas, M. and Arti{\~n}ano, B. and Artiñano, B. and Moreno, N. and Alastuey, A. and Querol, X.}, doi = {10.1016/s0021-8502(19)30236-8}, journal = {Journal of Aerosol Science}, month = {jan}, pages = {S1001-S1002}, title = {Measurement of particulate matter emitted during bulk handling activities in a harbour area in Spain}, url = {https://oadoi.org/10.1016/s0021-8502(19)30236-8}, volume = {35}, year = {2004} } @article{Hernández2003, author = {Hernández, S. and Juan, R. and Querol, X. and Alastuey, A. and Ferrer, P. and Andrés, J. M.}, month = {jan}, title = {Fly for activation pollutant gas retention | Activación de cenizas volantes para retención de gases contaminantes}, year = {2003} } @article{Laj2020, abstract = {Abstract. Aerosol particles are essential constituents of the Earth's atmosphere, impacting the earth radiation balance directly by scattering and absorbing solar radiation, and indirectly by acting as cloud condensation nuclei. In contrast to most greenhouse gases, aerosol particles have short atmospheric residence times, resulting in a highly heterogeneous distribution in space and time. There is a clear need to document this variability at regional scale through observations involving, in particular, the in situ near-surface segment of the atmospheric observation system. This paper will provide the widest effort so far to document variability of climate-relevant in situ aerosol properties (namely wavelength dependent particle light scattering and absorption coefficients, particle number concentration and particle number size distribution) from all sites connected to the Global Atmosphere Watch network. High-quality data from almost 90 stations worldwide have been collected and controlled for quality and are reported for a reference year in 2017, providing a very extended and robust view of the variability of these variables worldwide. The range of variability observed worldwide for light scattering and absorption coefficients, single-scattering albedo, and particle number concentration are presented together with preliminary information on their long-term trends and comparison with model simulation for the different stations. The scope of the present paper is also to provide the necessary suite of information, including data provision procedures, quality control and analysis, data policy, and usage of the ground-based aerosol measurement network. It delivers to users of the World Data Centre on Aerosol, the required confidence in data products in the form of a fully characterized value chain, including uncertainty estimation and requirements for contributing to the global climate monitoring system. }, author = {Laj, Paolo and Bigi, Alessandro and Rose, Clémence and Andrews, Elisabeth and Lund Myhre, Cathrine and Collaud Coen, Martine and Lin, Yong and Wiedensohler, Alfred and Schulz, Michael and Ogren, John A. and Fiebig, Markus and Gliß, Jonas and Mortier, Augustin and Pandolfi, Marco and Petäja, Tuukka and Kim, Sang-Woo and Aas, Wenche and Putaud, Jean-Philippe and Mayol-Bracero, Olga and Keywood, Melita and Labrador, Lorenzo and Aalto, Pasi and Ahlberg, Erik and Alados Arboledas, Lucas and Alastuey, Andrés and Andrade, Marcos and Artíñano, Begoña and Ausmeel, Stina and Arsov, Todor and Asmi, Eija and Backman, John and Baltensperger, Urs and Bastian, Susanne and Bath, Olaf and Beukes, Johan Paul and Brem, Benjamin T. and Bukowiecki, Nicolas and Conil, Sébastien and Couret, Cedric and Day, Derek and Dayantolis, Wan and Degorska, Anna and Eleftheriadis, Konstantinos and Fetfatzis, Prodromos and Favez, Olivier and Flentje, Harald and Gini, Maria I. and Gregorič, Asta and Gysel-Beer, Martin and Hallar, A. Gannet and Hand, Jenny and Hoffer, Andras and Hueglin, Christoph and Hooda, Rakesh K. and Hyvärinen, Antti and Kalapov, Ivo and Kalivitis, Nikos and Kasper-Giebl, Anne and Kim, Jeong Eun and Kouvarakis, Giorgos and Kranjc, Irena and Krejci, Radovan and Kulmala, Markku and Labuschagne, Casper and Lee, Hae-Jung and Lihavainen, Heikki and Lin, Neng-Huei and Löschau, Gunter and Luoma, Krista and Marinoni, Angela and Martins Dos Santos, Sebastiao and Meinhardt, Frank and Merkel, Maik and Metzger, Jean-Marc and Mihalopoulos, Nikolaos and Nguyen, Nhat Anh and Ondracek, Jakub and Pérez, Noemi and Perrone, Maria Rita and Petit, Jean-Eudes and Picard, David and Pichon, Jean-Marc and Pont, Veronique and Prats, Natalia and Prenni, Anthony and Reisen, Fabienne and Romano, Salvatore and Sellegri, Karine and Sharma, Sangeeta and Schauer, Gerhard and Sheridan, Patrick and Sherman, James Patrick and Schütze, Maik and Schwerin, Andreas and Sohmer, Ralf and Sorribas, Mar and Steinbacher, Martin and Sun, Junying and Titos, Gloria and Toczko, Barbara and Tuch, Thomas and Tulet, Pierre and Tunved, Peter and Vakkari, Ville and Velarde, Fernando and Velasquez, Patricio and Villani, Paolo and Vratolis, Sterios and Wang, Sheng-Hsiang and Weinhold, Kay and Weller, Rolf and Yela, Margarita and Yus-Diez, Jesus and Zdimal, Vladimir and Zieger, Paul and Zikova, Nadezda}, doi = {10.5194/amt-13-4353-2020}, journal = {Atmospheric Measurement Techniques}, month = {aug}, pages = {4353-4392}, title = {A global analysis of climate-relevant aerosol properties retrieved from the network of Global Atmosphere Watch (GAW) near-surface observatories}, url = {https://doi.org/10.5194/amt-13-4353-2020}, volume = {13}, year = {2020} } @article{L{̈u}2007, author = {L{̈u}, W. W. and Lü, W. W. and Alastuey, A. and Wang, Y. X. and Querol, X.}, doi = {10.1201/noe0415451369.ch314}, journal = {Water-Rock Interaction}, month = {jul}, title = {Geochemistry of Rare Earth Elements in PM10 of atmospheric particulates in Wuhan, central China}, url = {https://oadoi.org/10.1201/noe0415451369.ch314}, year = {2007} } @article{Ostro2011, abstract = {Background: Dozens of studies link acute exposure to particulate matter (PM) air pollution with premature mortality and morbidity, but questions remain about which species and sources in the vast PM mixture are responsible for the observed health effects. Although a few studies exist on the effects of species and sources in U.S. cities, European cities—which have a higher proportion of diesel engines and denser urban populations—have not been well characterized. Information on the effects of specific sources could aid in targeting pollution control and in articulating the biological mechanisms of PM.}, author = {Ostro, Bart and Tobias, Aurelio and Querol, Xavier and Alastuey, Andrés and Amato, Fulvio and Pey, Jorge and Pérez, Noemí and Sunyer, Jordi}, doi = {10.1289/ehp.1103618}, journal = {Environmental Health Perspectives}, month = {aug}, pages = {1781-1787}, title = {The Effects of Particulate Matter Sources on Daily Mortality: A Case-Crossover Study of Barcelona, Spain}, url = {https://doi.org/10.1289/ehp.1103618}, volume = {119}, year = {2011} } @article{Putaud2023, abstract = {To fight against the first wave of coronavirus disease 2019 (COVID-19) in 2020, lockdown measures were implemented in most European countries. These lockdowns had well-documented effects on human mobility. We assessed the impact of the lockdown implementation and relaxation on air pollution by comparing daily particulate matter (PM), nitrogen dioxide (NO2) and ozone (O3) concentrations, as well as particle number size distributions (PNSDs) and particle light absorption coefficient in situ measurement data, with values that would have been expected if no COVID-19 epidemic had occurred at 28 sites across Europe for the period 17 February–31 May 2020. Expected PM, NO2 and O3 concentrations were calculated from the 2020 Copernicus Atmosphere Monitoring Service (CAMS) ensemble forecasts, combined with 2019 CAMS ensemble forecasts and measurement data. On average, lockdown implementations did not lead to a decrease in PM2.5 mass concentrations at urban sites, while relaxations resulted in a +26 ± 21 % rebound. The impacts of lockdown implementation and relaxation on NO2 concentrations were more consistent (−29 ± 17 and +31 ± 30 %, respectively). The implementation of the lockdown measures also induced statistically significant increases in O3 concentrations at half of all sites (+13 % on average). An enhanced oxidising capacity of the atmosphere could have boosted the production of secondary aerosol at those places. By comparison with 2017–2019 measurement data, a significant change in the relative contributions of wood and fossil fuel burning to the concentration of black carbon during the lockdown was detected at 7 out of 14 sites. The contribution of particles smaller than 70 nm to the total number of particles significantly also changed at most of the urban sites, with a mean decrease of −7 ± 5 % coinciding with the lockdown implementation. Our study shows that the response of PM2.5 and PM10 mass concentrations to lockdown measures was not systematic at various sites across Europe for multiple reasons, the relationship between road traffic intensity and particulate air pollution being more complex than expected. }, author = {Putaud, Jean-Philippe and van der Gon, Hugo Denier and Pisoni, Enrico and Mangold, Alexander and Hueglin, Christoph and Sciare, Jean and Pikridas, Michael and Savvides, Chrysanthos and Ondracek, Jakub and Mbengue, Saliou and Wiedensohler, Alfred and Weinhold, Kay and Merkel, Maik and Poulain, Laurent and van Pinxteren, Dominik and Herrmann, Hartmut and Massling, Andreas and Nordstroem, Claus and Alastuey, Andrés and Reche, Cristina and Pérez, Noemí and Castillo, Sonia and Sorribas, Mar and Adame, Jose Antonio and Petaja, Tuukka and Lehtipalo, Katrianne and Niemi, Jarkko and Riffault, Véronique and de Brito, Joel F. and Colette, Augustin and Favez, Olivier and Petit, Jean-Eudes and Gros, Valérie and Gini, Maria I. and Vratolis, Stergios and Eleftheriadis, Konstantinos and Diapouli, Evangelia and Denier van der Gon, Hugo and Yttri, Karl Espen and Aas, Wenche}, doi = {10.5194/acp-23-10145-2023}, journal = {Atmospheric Chemistry and Physics}, month = {sep}, pages = {10145-10161}, title = {Impact of 2020 COVID-19 lockdowns on particulate air pollution across Europe}, url = {https://doi.org/10.5194/acp-23-10145-2023}, volume = {23}, year = {2023} } @article{Rose2021, abstract = {Aerosol particles are a complex component of the atmospheric system which influence climate directly by interacting with solar radiation, and indirectly by contributing to cloud formation. The variety of their sources, as well as the multiple transformations they may undergo during their transport (including wet and dry deposition), result in significant spatial and temporal variability of their properties. Documenting this variability is essential to provide a proper representation of aerosols and cloud condensation nuclei (CCN) in climate models. Using measurements conducted in 2016 or 2017 at 62 ground-based stations around the world, this study provides the most up-to-date picture of the spatial distribution of particle number concentration (Ntot) and number size distribution (PNSD, from 39 sites). A sensitivity study was first performed to assess the impact of data availability on Ntot's annual and seasonal statistics, as well as on the analysis of its diel cycle. Thresholds of 50 % and 60 % were set at the seasonal and annual scale, respectively, for the study of the corresponding statistics, and a slightly higher coverage (75 %) was required to document the diel cycle. Although some observations are common to a majority of sites, the variety of environments characterizing these stations made it possible to highlight contrasting findings, which, among other factors, seem to be significantly related to the level of anthropogenic influence. The concentrations measured at polar sites are the lowest (∼ 102 cm−3) and show a clear seasonality, which is also visible in the shape of the PNSD, while diel cycles are in general less evident, due notably to the absence of a regular day–night cycle in some seasons. In contrast, the concentrations characteristic of urban environments are the highest (∼ 103–104 cm−3) and do not show pronounced seasonal variations, whereas diel cycles tend to be very regular over the year at these stations. The remaining sites, including mountain and non-urban continental and coastal stations, do not exhibit as obvious common behaviour as polar and urban sites and display, on average, intermediate Ntot (∼ 102–103 cm−3). Particle concentrations measured at mountain sites, however, are generally lower compared to nearby lowland sites, and tend to exhibit somewhat more pronounced seasonal variations as a likely result of the strong impact of the atmospheric boundary layer (ABL) influence in connection with the topography of the sites. ABL dynamics also likely contribute to the diel cycle of Ntot observed at these stations. Based on available PNSD measurements, CCN-sized particles (considered here as either >50 nm or >100 nm) can represent from a few percent to almost all of Ntot, corresponding to seasonal medians on the order of ∼ 10 to 1000 cm−3, with seasonal patterns and a hierarchy of the site types broadly similar to those observed for Ntot. Overall, this work illustrates the importance of in situ measurements, in particular for the study of aerosol physical properties, and thus strongly supports the development of a broad global network of near surface observatories to increase and homogenize the spatial coverage of the measurements, and guarantee as well data availability and quality. The results of this study also provide a valuable, freely available and easy to use support for model comparison and validation, with the ultimate goal of contributing to improvement of the representation of aerosol–cloud interactions in models, and, therefore, of the evaluation of the impact of aerosol particles on climate. }, author = {Rose, Clémence and Collaud Coen, Martine and Andrews, Elisabeth and Lin, Yong and Bossert, Isaline and Lund Myhre, Cathrine and Myhre, Cathrine Lund and Tuch, Thomas and Wiedensohler, Alfred and Fiebig, Markus and Aalto, Pasi and Alastuey, Andrés and Alonso-Blanco, Elisabeth and Andrade, Marcos and Artíñano, Begoña and Arsov, Todor and Baltensperger, Urs and Bastian, Susanne and Bath, Olaf and Beukes, Johan Paul and Brem, Benjamin T. and Bukowiecki, Nicolas and Casquero-Vera, Juan Andrés and Conil, Sébastien and Eleftheriadis, Konstantinos and Favez, Olivier and Flentje, Harald and Gini, Maria I. and Gómez-Moreno, Francisco Javier and Gysel-Beer, Martin and Gannet Hallar, A. and Hallar, Anna Gannet and Kalapov, Ivo and Kalivitis, Nikos and Kasper-Giebl, Anne and Keywood, Melita and Kim, Jeong Eun and Kim, Sang-Woo and Kristensson, Adam and Kulmala, Markku and Lihavainen, Heikki and Lin, Neng-Huei and Lyamani, Hassan and Marinoni, Angela and Martins Dos Santos, Sebastiao and Santos, Sebastiao Martins Dos and Mayol-Bracero, Olga L. and Meinhardt, Frank and Merkel, Maik and Metzger, Jean-Marc and Mihalopoulos, Nikolaos and Ondracek, Jakub and Pandolfi, Marco and Pérez, Noemi and Petäjä, Tuukka and Petit, Jean-Eudes and Picard, David and Pichon, Jean-Marc and Pont, Veronique and Putaud, Jean-Philippe and Reisen, Fabienne and Sellegri, Karine and Sharma, Sangeeta and Schauer, Gerhard and Sheridan, Patrick and Sherman, James Patrick and Schwerin, Andreas and Sohmer, Ralf and Sorribas, Mar and Sun, Junying and Tulet, Pierre and Vakkari, Ville and van Zyl, Pieter Gideon and Velarde, Fernando and Villani, Paolo and Vratolis, Stergios and Wagner, Zdenek and Wang, Sheng-Hsiang and Weinhold, Kay and Weller, Rolf and Yela, Margarita and Zdimal, Vladimir and Laj, Paolo}, doi = {10.5194/acp-21-17185-2021}, journal = {Atmospheric Chemistry and Physics}, month = {nov}, pages = {17185-17223}, title = {Seasonality of the particle number concentration and size distribution: a global analysis retrieved from the network of Global Atmosphere Watch (GAW) near-surface observatories}, url = {https://doi.org/10.5194/acp-21-17185-2021}, volume = {21}, year = {2021} } @article{Stamenov2017, abstract = {Abstract. This paper presents the light-scattering properties of atmospheric aerosol particles measured over the past decade at 28 ACTRIS observatories, which are located mainly in Europe. The data include particle light scattering (σsp) and hemispheric backscattering (σbsp) coefficients, scattering Ångström exponent (SAE), backscatter fraction (BF) and asymmetry parameter (g). An increasing gradient of σsp is observed when moving from remote environments (arctic/mountain) to regional and to urban environments. At a regional level in Europe, σsp also increases when moving from Nordic and Baltic countries and from western Europe to central/eastern Europe, whereas no clear spatial gradient is observed for other station environments. The SAE does not show a clear gradient as a function of the placement of the station. However, a west-to-east-increasing gradient is observed for both regional and mountain placements, suggesting a lower fraction of fine-mode particle in western/south-western Europe compared to central and eastern Europe, where the fine-mode particles dominate the scattering. The g does not show any clear gradient by station placement or geographical location reflecting the complex relationship of this parameter with the physical properties of the aerosol particles. Both the station placement and the geographical location are important factors affecting the intra-annual variability. At mountain sites, higher σsp and SAE values are measured in the summer due to the enhanced boundary layer influence and/or new particle-formation episodes. Conversely, the lower horizontal and vertical dispersion during winter leads to higher σsp values at all low-altitude sites in central and eastern Europe compared to summer. These sites also show SAE maxima in the summer (with corresponding g minima). At all sites, both SAE and g show a strong variation with aerosol particle loading. The lowest values of g are always observed together with low σsp values, indicating a larger contribution from particles in the smaller accumulation mode. During periods of high σsp values, the variation of g is less pronounced, whereas the SAE increases or decreases, suggesting changes mostly in the coarse aerosol particle mode rather than in the fine mode. Statistically significant decreasing trends of σsp are observed at 5 out of the 13 stations included in the trend analyses. The total reductions of σsp are consistent with those reported for PM2.5 and PM10 mass concentrations over similar periods across Europe. }, author = {Stamenov, Dimiter B. and Pandolfi, Marco and Alados-Arboledas, Lucas and Alastuey, Andrés and Andrade, Marcos and Angelov, Christo and Artiñano, Begoña and Backman, John and Collaud Coen, Martine and Baltensperger, Urs and Coz, Esther and Crenn, Vincent and Bonasoni, Paolo and Dudoitis, Vadimas and Ealo, Marina and Bukowiecki, Nicolas and Conil, Sebastian and Eleftheriadis, Kostas and Favez, Olivier and Fetfatzis, Prodromos and Fiebig, Markus and Flentje, Harald and Ginot, Patrick and Gysel, Martin and Henzing, Bas and Hoffer, Andras and Holubova Smejkalova, Adela and Kalapov, Ivo and Kalivitis, Nikos and Petäjä, Tuukka and Kouvarakis, Giorgos and Petit, Jean-Eudes and Kristensson, Adam and Pichon, Jean Marc and Kulmala, Markku and Prokopciuk, Nina and Lihavainen, Heikki and Putaud, Jean-Philippe and Lunder, Chris and Rodríguez, Sergio and Luoma, Krista and Lyamani, Hassan and Sciare, Jean and Marinoni, Angela and Sellegri, Karine and Mihalopoulos, Nikos and Swietlicki, Erik and Moerman, Marcel and Titos, Gloria and Nicolas, José and Tuch, Thomas and O'Dowd, Colin and Tunved, Peter and Ulevicius, Vidmantas and Vaishya, Aditya and Vana, Milan and Virkkula, Aki and Vratolis, Stergios and Weingartner, Ernest and Wiedensohler, Alfred and O&apos;Dowd, Colin and Laj, Paolo}, doi = {10.5194/acp-18-7877-2018}, journal = {Atmospheric Chemistry and Physics Discussions}, month = {oct}, pages = {1-51}, title = {A European aerosol phenomenology-6: Scattering properties of atmospheric aerosol particles from 28 ACTRIS sites}, url = {https://doi.org/10.5194/acp-2017-826}, volume = {18}, year = {2017} } @article{Titos2017, author = {Titos, G. and Ealo, M. and Pandolfi, M. and Pérez, N. and Sola, Y. and Sicard, M. and Comerón, A. and Querol, X. and Alastuey, A.}, doi = {10.1002/2016jd026252}, journal = {Journal of Geophysical Research: Atmospheres}, month = {apr}, pages = {4052-4069}, title = {Spatiotemporal evolution of a severe winter dust event in the western Mediterranean: Aerosol optical and physical properties: Dust Optical and Physical Properties}, url = {https://doi.org/10.1002/2016jd026252}, volume = {122}, year = {2017} } @article{Trechera2023, author = {Trechera, Pedro and Garcia-Marlès, Meritxell and Liu, Xiansheng and Reche, Cristina and Pérez, Noemí and Savadkoohi, Marjan and Beddows, David and Salma, Imre and Vörösmarty, Máté and Casans, Andrea and Casquero-Vera, Juan Andrés and Hueglin, Christoph and Marchand, Nicolas and Chazeau, Benjamin and Gille, Grégory and Kalkavouras, Panayiotis and Mihalopoulos, Nikos and Ondracek, Jakub and Zikova, Nadia and Niemi, Jarkko V. and Manninen, Hanna Elina and Green, David C. and Tremper, Anja H. and Norman, Michael and Vratolis, Stergios and Eleftheriadis, Konstantinos and Gómez-Moreno, Francisco J. and Alonso-Blanco, Elisabeth and Gerwig, Holger and Wiedensohler, Alfred and Weinhold, Kay and Merkel, Maik and Bastian, Susanne and Petit, Jean-Eudes and Favez, Olivier and Crumeyrolle, Suzanne and Ferlay, Nicolas and Dos Santos, Sebastiao Martins and Martins Dos Santos, Sebastiao and Putaud, Jean-Philippe and Timonen, Hilkka and Lampilahti, Janne and Asbach, Christof and Wolf, Carmen and Kaminski, Heinz and Altug, Hicran and Hoffmann, Barbara and Rich, David Q. and Pandolfi, Marco and Harrison, Roy M. and Hopke, Philip K. and Petäjä, Tuukka and Alastuey, Andrés and Alaustey, A. and Querol, Xavier}, doi = {10.2139/ssrn.4294020}, journal = {Environment International}, month = {feb}, pages = {107744}, title = {Phenomenology of ultrafine particle concentrations and size distribution across urban Europe}, url = {https://doi.org/10.2139/ssrn.4294020}, volume = {172}, year = {2023} } @article{Wong2021, author = {Wong, Michelle Y. and Yu‐Cheng, Chen and Rathod, Sagar D. and Marino, Roxanne and Li, Longlei and Howarth, Robert W. and Alastuey, Andres and Alaimo, Maria Grazia and Barraza, Francisco and Carneiro, Manuel Castro and Chellam, Shankararaman and Cohen, David D. and Connelly, David and Dongarra, Gaetano and Gomez, Dario and Hand, Jenny and Harrison, R. M. and Hopke, Philip K. and Hueglin, Christoph and Kuang, Yuan‐wen and Lambert, Fabrice and Liang, James and Losno, Remi and Maenhaut, Willy and Milando, Chad and Monteiro, Maria Inês Couto and Morera‐Gómez, Yasser and Querol, Xavier and Rodríguez, Sergio and Smichowski, Patricia and Varrica, Daniela and Xiao, Yi‐hua and Xu, Yangjunjie and Mahowald, Natalie M.}, doi = {10.1029/2020gb006787}, journal = {Global Biogeochemical Cycles}, month = {jan}, title = {Anthropogenic Perturbations to the Atmospheric Molybdenum Cycle}, url = {https://onlinelibrary.wiley.com/doi/pdf/10.1029/2020GB006787}, volume = {35}, year = {2021} }