38 results on '"number concentrations"'
Search Results
2. Survival probabilities of atmospheric particles : comparison based on theory,cluster population simulations, and observations in Beijing
- Author
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Santeri Tuovinen, Runlong Cai, Veli-Matti Kerminen, Jingkun Jiang, Chao Yan, Markku Kulmala, Jenni Kontkanen, Institute for Atmospheric and Earth System Research (INAR), Air quality research group, Department of Physics, and Global Atmosphere-Earth surface feedbacks
- Subjects
Aerosols ,Atmospheric Science ,Coagulation ,Growth-rates ,Number concentrations ,Sulfuric-acid ,Molecular clusters ,Cloud condensation nuclei ,Size distributions ,3 nm ,Nucleation rates ,114 Physical sciences - Abstract
Atmospheric new particle formation (NPF) events are regularly observed in urban Beijing, despite high concentrations of background particles which, based on theory, should inhibit NPF due to high values of coagulation sink (CoagS). The survival probability, which depends on both CoagS and particle growth rate (GR), is a key parameter in determining the occurrence of NPF events as it describes the fraction of newly formed particles that survive from a smaller diameter to a larger diameter. In this study, we investigate and compare survival probabilities from 1.5 to 3 nm (J3/J1.5), from 3 to 6 nm (J6/J3), and from 6 to 10 nm (J10/J6) based on analytical formulae, cluster population simulations, and atmospheric observations from Beijing. We find that survival probabilities based on the cluster population simulations and one of the analytical formulae are in a good agreement. However, at low ratios between the background condensation sink (CS) and GR, and at high concentrations of sub-3 nm clusters, cluster–cluster collisions efficiently lower survival probabilities in the cluster population simulations. Due to the large concentrations of clusters and small particles required to considerably affect the survival probabilities, we consider it unlikely that cluster–cluster collisions significantly affect atmospheric survival probabilities. The values of J10/J6 observed in Beijing show high variability, most likely due to influences of primary particle emissions, but are on average in relatively good agreement with the values based on the simulations and the analytical formulae. The observed values of J6/J3 are mostly lower than those predicted based on the simulations and the analytical formulae, which could be explained by uncertainties in CS and GR. The observed values of J3/J1.5 at high CS / GR are much higher than predicted based on the simulations and the analytical formulae. We argue that uncertainties in GR or CS are unlikely to solely explain the observed values of J3/J1.5 under high CS conditions. Thus, further work is needed to better understand the factors influencing survival probabilities of sub-3 nm atmospheric particles in polluted environments.
- Published
- 2022
3. Vertical Profiles of Pollution Particle Concentrations in the Boundary Layer above Paris (France) from the Optical Aerosol Counter LOAC Onboard a Touristic Balloon
- Author
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Jean-Baptiste Renard, Vincent Michoud, and Jérôme Giacomoni
- Subjects
particulate matter ,urban pollution ,number concentrations ,tethered balloon ,Chemical technology ,TP1-1185 - Abstract
Atmospheric pollution by particulate matter represents a significant health risk and needs continuous monitoring by air quality networks that provide mass concentrations for PM10 and PM2.5 (particles with diameter smaller than 10 μm and 2.5 μm, respectively). We present here a new approach to monitor the urban particles content, using six years of aerosols number concentration measurements for particles in the 0.2−50 μm size range. These measurements are performed by the Light Optical Aerosols Counter (LOAC) instrument onboard the tethered touristic balloon “Ballon de Paris Generali”, in Paris, France. Such measurements have allowed us first to detect at ground a seasonal variability in the particulate matter content, due to the origin of the particles (anthropogenic pollution, pollens), and secondly, to retrieve the mean evolution of particles concentrations with height above ground up to 150 m. Measurements were also conducted up to 300 m above ground during major pollution events. The vertical evolution of concentrations varies from one event to another, depending on the origin of the pollution and on the meteorological conditions. These measurements have shown the interest of performing particle number concentrations measurements for the air pollution monitoring in complement with regulatory mass concentrations measurement, to better evaluate the intensity of the pollution event and to better consider the effect of smallest particles, which are more dangerous for human health.
- Published
- 2020
- Full Text
- View/download PDF
4. 京津冀中部夏季大气颗粒物空间分布特征.
- Author
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孟凡胜, 王飞, 殷宝辉, 耿春梅, 杨文, 李伟, and 白志鹏
- Abstract
Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
- Full Text
- View/download PDF
5. Differences in removal rates of virgin/decayed microplastics, viruses, activated carbon, and kaolin/montmorillonite clay particles by coagulation, flocculation, sedimentation, and rapid sand filtration during water treatment
- Abstract
One of the main purposes of drinking water treatment is to reduce turbidity originating from clay particles. Relatively little is known about the removal of other types of particles, including conventionally sized powdered activated carbon (PAC) and superfine PAC (SPAC), which are intentionally added during the treatment process; microplastic particles; and viruses. To address this knowledge gap, we conducted a preliminary investigation in full-scale water treatment plants and then studied the removal of these particles during coagulation-flocculation, sedimentation, and rapid sand filtration (CSF) in bench-scale experiments in which these particles were present together. Numbers of all target particles were greatly decreased by coagulation-flocculation and sedimentation (CS). Subsequent rapid sand filtration greatly reduced the concentrations of PAC and SPAC but not the concentrations of viruses, microplastic particles, and clay particles. Overall removal rates by CSF were 4.6 logs for PAC and SPAC, 3.5 logs for viruses, 2.9 logs for microplastics, and 2.8 logs for clay. The differences in removals were not explained by particle sizes or zeta potentials. However, for clays, PAC and SPAC, for which the particle size distributions were wide, smaller particles were less efficiently removed. The ratios of both clay to PAC and clay to SPAC particles increased greatly after rapid sand filtration because removal rates of PAC and SPAC particles were about 2 logs higher than removal rates of clay particles. The trend of greater reduction of PAC concentrations than turbidity was confirmed by measurements made in 14 full-scale water purification plants in which residual concentrations of PAC in treated water were very low, 40–200 particles/mL. Clay particles therefore accounted for most of the turbidity in sand filtrate, even though PAC was employed. The removal rate of microplastic particles was comparable to that of clays. Sufficient turbidity removal would therefore provid
- Published
- 2021
6. Differences in removal rates of virgin/decayed microplastics, viruses, activated carbon, and kaolin/montmorillonite clay particles by coagulation, flocculation, sedimentation, and rapid sand filtration during water treatment
- Abstract
One of the main purposes of drinking water treatment is to reduce turbidity originating from clay particles. Relatively little is known about the removal of other types of particles, including conventionally sized powdered activated carbon (PAC) and superfine PAC (SPAC), which are intentionally added during the treatment process; microplastic particles; and viruses. To address this knowledge gap, we conducted a preliminary investigation in full-scale water treatment plants and then studied the removal of these particles during coagulation-flocculation, sedimentation, and rapid sand filtration (CSF) in bench-scale experiments in which these particles were present together. Numbers of all target particles were greatly decreased by coagulation-flocculation and sedimentation (CS). Subsequent rapid sand filtration greatly reduced the concentrations of PAC and SPAC but not the concentrations of viruses, microplastic particles, and clay particles. Overall removal rates by CSF were 4.6 logs for PAC and SPAC, 3.5 logs for viruses, 2.9 logs for microplastics, and 2.8 logs for clay. The differences in removals were not explained by particle sizes or zeta potentials. However, for clays, PAC and SPAC, for which the particle size distributions were wide, smaller particles were less efficiently removed. The ratios of both clay to PAC and clay to SPAC particles increased greatly after rapid sand filtration because removal rates of PAC and SPAC particles were about 2 logs higher than removal rates of clay particles. The trend of greater reduction of PAC concentrations than turbidity was confirmed by measurements made in 14 full-scale water purification plants in which residual concentrations of PAC in treated water were very low, 40–200 particles/mL. Clay particles therefore accounted for most of the turbidity in sand filtrate, even though PAC was employed. The removal rate of microplastic particles was comparable to that of clays. Sufficient turbidity removal would therefore provid
- Published
- 2021
7. Data imputation in in situ-measured particle size distributions by means of neural networks
- Author
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Fung, Pak Lun, Zaidan, Martha Arbayani, Surakhi, Ola, Tarkoma, Sasu, Petäjä, Tuukka, Hussein, Tareq, Institute for Atmospheric and Earth System Research (INAR), Helsinki Institute of Sustainability Science (HELSUS), Air quality research group, Global Atmosphere-Earth surface feedbacks, Content-Centric Structures and Networking research group / Sasu Tarkoma, Department of Computer Science, and Helsinki Institute for Information Technology
- Subjects
ULTRAFINE PARTICLES ,GROWTH-RATES ,MOBILITY ,PREDICTION ,AIRBORNE NANOPARTICLES ,NUMBER CONCENTRATIONS ,AEROSOL ,INVERSION ,URBAN ,114 Physical sciences ,MIDDLE-EAST - Abstract
In air quality research, often only size-integrated particle mass concentrations as indicators of aerosol particles are considered. However, the mass concentrations do not provide sufficient information to convey the full story of fractionated size distribution, in which the particles of different diameters (Dp) are able to deposit differently on respiratory system and cause various harm. Aerosol size distribution measurements rely on a variety of techniques to classify the aerosol size and measure the size distribution. From the raw data the ambient size distribution is determined utilising a suite of inversion algorithms. However, the inversion problem is quite often ill-posed and challenging to solve. Due to the instrumental insufficiency and inversion limitations, imputation methods for fractionated particle size distribution are of great significance to fill the missing gaps or negative values. The study at hand involves a merged particle size distribution, from a scanning mobility particle sizer (NanoSMPS) and an optical particle sizer (OPS) covering the aerosol size distributions from 0.01 to 0.42 µm (electrical mobility equivalent size) and 0.3 to 10 µm (optical equivalent size) and meteorological parameters collected at an urban background region in Amman, Jordan, in the period of 1 August 2016–31 July 2017. We develop and evaluate feed-forward neural network (FFNN) approaches to estimate number concentrations at particular size bin with (1) meteorological parameters, (2) number concentration at other size bins and (3) both of the above as input variables. Two layers with 10–15 neurons are found to be the optimal option. Worse performance is observed at the lower edge (0.01
- Published
- 2021
8. Aerosols and Criteria Gases in an Underground Mine That Uses FAME Biodiesel Blends.
- Author
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Bugarski, Aleksandar D., Janisko, Samuel J., Cauda, Emanuele G., Patts, Larry D., Hummer, Jon A., Westover, Charles, and Terrillion, Troy
- Subjects
- *
AEROSOLS , *CARBOXYLIC acids , *GASES , *INDUSTRIAL safety , *MINERAL industries , *OXIDES , *POWER resources , *RESEARCH funding , *SULFUR , *TRANSPORTATION , *PARTICULATE matter , *DATA analysis software , *DESCRIPTIVE statistics - Abstract
The contribution of heavy-duty haulage trucks to the concentrations of aerosols and criteria gases in underground mine air and the physical properties of those aerosols were assessed for three fuel blends made with fatty acid methyl esters biodiesel and petroleum-based ultra-low-sulfur diesel (ULSD). The contributions of blends with 20, 50, and 57% of biodiesel as well as neat ULSD were assessed using a 30-ton truck operated over a simulated production cycle in an isolated zone of an operating underground metal mine. When fueled with the B20 (blend of biodiesel with ULSD with 20% of biodiesel content), B50 (blend of biodiesel with ULSD with 50% of biodiesel content), and B57 (blend of biodiesel with ULSD with 57% of biodiesel content) blends in place of ULSD, the truck’s contribution to mass concentrations of elemental and total carbon was reduced by 20, 50, and 61%, respectively. Size distribution measurements showed that the aerosols produced by the engine fueled with these blends were characterized by smaller median electrical mobility diameter and lower peak concentrations than the aerosols produced by the same engine fueled with ULSD. The use of the blends resulted in number concentrations of aerosols that were 13–29% lower than those when ULSD was used. Depending on the content of biodiesel in the blends, the average reductions in the surface area concentrations of aerosol which could be deposited in the alveolar region of the lung (as measured by a nanoparticle surface area monitor) ranged between 6 and 37%. The use of blends also resulted in slight but measurable reductions in CO emissions, as well as an increase in NOX emissions. All of the above changes in concentrations and physical properties were found to be correlated with the proportion of biodiesel in the blends. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
9. Fine and ultrafine particle number and size measurements from industrial combustion processes: primary emissions field data
- Author
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Hélène Lepaumier, M. Zarea, L. Goossens, Michael E. Webber, Julien Blondeau, A. Duterque, Pieter Rogiers, Dominique Desagher, Jan Mertens, E. Le Cadre, Applied Mechanics, Faculty of Engineering, Combustion and Robust optimization, and Thermodynamics and Fluid Mechanics Group
- Subjects
Aerosols ,Flue gas ,Atmospheric Science ,Materials science ,Emission measurement ,010504 meteorology & atmospheric sciences ,WOOD COMBUSTION ,Analytical chemistry ,Electrostatic precipitator ,010501 environmental sciences ,Orders of magnitude (numbers) ,Particulates ,Combustion ,01 natural sciences ,Pollution ,Number concentrations ,Earth and Environmental Sciences ,Ultrafine particle ,Particle ,Nanoparticles ,Particle size ,Particulate matter ,ELPI+ ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
This study is to our knowledge the first to present the results of on-line measurements of residual nanoparticle numbers downstream of the flue gas treatment systems of a wide variety of medium- and large-scale industrial installations. Where available, a semi-quantitative elemental composition of the sampled particles is carried out using a Scanning Electron Microscope coupled with an Energy Dispersive Spectrometer (SEM-EDS). The semi-quantitative elemental composition as a function of the particle size is presented. EU's Best Available Technology documents (BAT) show removal efficiencies of Electrostatic Precipitator (ESP) and bag filter dedusting systems exceeding 99% when expressed in terms of weight. Their efficiency decreases slightly for particles smaller than 1 μm but when expressed in terms of weight, still exceeds 99% for bag filters and 96% for ESP. This study reveals that in terms of particle numbers, residual nanoparticles (NP) leaving the dedusting systems dominate by several orders of magnitude. In terms of weight, all installations respect their emission limit values and the contribution of NP to weight concentrations is negligible, despite their dominance in terms of numbers. Current World Health Organisation regulations are expressed in terms of PM2.5 wt concentrations and therefore do not reflect the presence or absence of a high number of NP. This study suggests that research is needed on possible additional guidelines related to NP given their possible toxicity and high potential to easily enter the blood stream when inhaled by humans.
- Published
- 2020
10. Vertical Profiles of Pollution Particle Concentrations in the Boundary Layer above Paris (France) from the Optical Aerosol Counter LOAC Onboard a Touristic Balloon
- Author
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Vincent Michoud, Jean-Baptiste Renard, Jérôme Giacomoni, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire Imagerie et Systèmes d'Acquisition (LISA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Aerophile SAS, ADEME (project MESUrPOP) CORTEA / contract number 1762C0004, and ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010)
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Pollution ,010504 meteorology & atmospheric sciences ,Particle number ,Aircraft ,media_common.quotation_subject ,tethered balloon ,Air pollution ,010501 environmental sciences ,Atmospheric sciences ,medicine.disease_cause ,lcsh:Chemical technology ,01 natural sciences ,Biochemistry ,complex mixtures ,Article ,Analytical Chemistry ,Keyworks: particulate matter ,Meteorology ,Air Pollution ,11. Sustainability ,medicine ,Humans ,lcsh:TP1-1185 ,Electrical and Electronic Engineering ,Particle Size ,Instrumentation ,Air quality index ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,media_common ,Aerosols ,particulate matter ,[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph] ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,Range (particle radiation) ,Air Pollutants ,[SDE.IE]Environmental Sciences/Environmental Engineering ,Particulates ,Atomic and Molecular Physics, and Optics ,Aerosol ,number concentrations ,13. Climate action ,Particle ,Environmental science ,France ,Seasons ,urban pollution ,Environmental Monitoring - Abstract
Atmospheric pollution by particulate matter represents a significant health risk and needs continuous monitoring by air quality networks that provide mass concentrations for PM10 and PM2.5 (particles with diameter smaller than 10 m and 2.5 m, respectively). We present here a new approach to monitor the urban particles content, using six years of aerosols number concentration measurements for particles in the 0.2&minus, 50 m size range. These measurements are performed by the Light Optical Aerosols Counter (LOAC) instrument onboard the tethered touristic balloon &ldquo, Ballon de Paris Generali&rdquo, in Paris, France. Such measurements have allowed us first to detect at ground a seasonal variability in the particulate matter content, due to the origin of the particles (anthropogenic pollution, pollens), and secondly, to retrieve the mean evolution of particles concentrations with height above ground up to 150 m. Measurements were also conducted up to 300 m above ground during major pollution events. The vertical evolution of concentrations varies from one event to another, depending on the origin of the pollution and on the meteorological conditions. These measurements have shown the interest of performing particle number concentrations measurements for the air pollution monitoring in complement with regulatory mass concentrations measurement, to better evaluate the intensity of the pollution event and to better consider the effect of smallest particles, which are more dangerous for human health.
- Published
- 2020
11. Sources and sinks driving sulfuric acid concentrations in contrasting environments: implications on proxy calculations
- Author
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L. Dada, I. Ylivinkka, R. Baalbaki, C. Li, Y. Guo, C. Yan, L. Yao, N. Sarnela, T. Jokinen, K. R. Daellenbach, R. Yin, C. Deng, B. Chu, T. Nieminen, Y. Wang, Z. Lin, R. C. Thakur, J. Kontkanen, D. Stolzenburg, M. Sipilä, T. Hussein, P. Paasonen, F. Bianchi, I. Salma, T. Weidinger, M. Pikridas, J. Sciare, J. Jiang, Y. Liu, T. Petäjä, V.-M. Kerminen, M. Kulmala, Publica, Air quality research group, INAR Physics, Global Atmosphere-Earth surface feedbacks, Polar and arctic atmospheric research (PANDA), and Institute for Atmospheric and Earth System Research (INAR)
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,NUMBER CONCENTRATIONS ,LONG-TERM MEASUREMENTS ,116 Chemical sciences ,010501 environmental sciences ,VOLATILE ORGANIC-COMPOUNDS ,Atmospheric sciences ,01 natural sciences ,114 Physical sciences ,Sink (geography) ,Proxy (climate) ,lcsh:Chemistry ,chemistry.chemical_compound ,ATMOSPHERIC NUCLEATION ,0105 earth and related environmental sciences ,geography ,geography.geographical_feature_category ,PARTICLE FORMATION EVENTS ,Sulfuric acid ,BOUNDARY-LAYER ,Rural environment ,PTR-MS ,lcsh:QC1-999 ,chemistry ,lcsh:QD1-999 ,13. Climate action ,MASS-SPECTROMETER ,Mediterranean area ,Environmental science ,GROWTH ,AEROSOL-PARTICLES ,Urban environment ,lcsh:Physics - Abstract
Sulfuric acid has been shown to be a key driver for new particle formation and subsequent growth in various environments, mainly due to its low volatility. However, direct measurements of gas-phase sulfuric acid are oftentimes not available, and the current sulfuric acid proxies cannot predict, for example, its nighttime concentrations or result in significant discrepancies with measured values. Here, we define the sources and sinks of sulfuric acid in different environments and derive a new physical proxy for sulfuric acid to be utilized in locations and during periods when it is not measured. We used H2SO4 measurements from four different locations: Hyytiälä, Finland; Agia Marina, Cyprus; Budapest, Hungary; and Beijing, China, representing semi-pristine boreal forest, rural environment in the Mediterranean area, urban environment and heavily polluted megacity, respectively. The new proxy takes into account the formation of sulfuric acid from SO2 via OH oxidation and other oxidation pathways, specifically via stabilized Criegee intermediates. The sulfuric acid sinks included in the proxy are its condensation sink (CS) and atmospheric clustering starting from H2SO4 dimer formation. Indeed, we found that the observed sulfuric acid concentration can be explained by the proposed sources and sinks with similar coefficients in the four contrasting environments where we have tested it. Thus, the new proxy is a more flexible and an important improvement over previous proxies. Following the recommendations in this paper, a proxy for a specific location can be derived.
- Published
- 2020
- Full Text
- View/download PDF
12. Modeling of the Concentrations of Ultrafine Particles in the Plumes of Ships in the Vicinity of Major Harbors
- Author
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Martin Otto Paul Ramacher, Matthias Karl, Jukka-Pekka Jalkanen, Liisa Pirjola, Ari Karppinen, Jaakko Kukkonen, and Department of Physics
- Subjects
010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,NUMBER CONCENTRATIONS ,lcsh:Medicine ,010501 environmental sciences ,Atmospheric sciences ,01 natural sciences ,114 Physical sciences ,Article ,ORGANIC VAPORS ,chemistry.chemical_compound ,ACID-WATER NUCLEATION ,SULFURIC-ACID ,shipping emissions ,Ultrafine particle ,HEAVY-DUTY ,Cities ,Sulfate ,OXIDATIVE STRESS ,Scavenging ,Air quality index ,Finland ,Ships ,0105 earth and related environmental sciences ,Air Pollutants ,particle number concentration ,SIZE DISTRIBUTIONS ,PARTICULATE AIR-POLLUTION ,lcsh:R ,Public Health, Environmental and Occupational Health ,population exposure ,Models, Theoretical ,Atmospheric dispersion modeling ,air quality ,3142 Public health care science, environmental and occupational health ,atmospheric nucleation ,Aerosol ,Plume ,ultrafine particles ,aerosol dynamics modeling ,chemistry ,EXHAUST EMISSIONS ,13. Climate action ,fuel sulfur content ,Environmental science ,Particulate Matter ,Dispersion (chemistry) ,Environmental Monitoring - Abstract
Marine traffic in harbors can be responsible for significant atmospheric concentrations of ultrafine particles (UFPs), which have widely recognized negative effects on human health. It is therefore essential to model and measure the time evolution of the number size distributions and chemical composition of UFPs in ship exhaust to assess the resulting exposure in the vicinity of shipping routes. In this study, a sequential modelling chain was developed and applied, in combination with the data measured and collected in major harbor areas in the cities of Helsinki and Turku in Finland, during winter and summer in 2010&ndash, 2011. The models described ship emissions, atmospheric dispersion, and aerosol dynamics, complemented with a time&ndash, microenvironment&ndash, activity model to estimate the short-term UFP exposure. We estimated the dilution ratio during the initial fast expansion of the exhaust plume to be approximately equal to eight. This dispersion regime resulted in a fully formed nucleation mode (denoted as Nuc2). Different selected modelling assumptions about the chemical composition of Nuc2 did not have an effect on the formation of nucleation mode particles. Aerosol model simulations of the dispersing ship plume also revealed a partially formed nucleation mode (Nuc1, peaking at 1.5 nm), consisting of freshly nucleated sulfate particles and condensed organics that were produced within the first few seconds. However, subsequent growth of the new particles was limited, due to efficient scavenging by the larger particles originating from the ship exhaust. The transport of UFPs downwind of the ship track increased the hourly mean UFP concentrations in the neighboring residential areas by a factor of two or more up to a distance of 3600 m, compared with the corresponding UFP concentrations in the urban background. The substantially increased UFP concentrations due to ship traffic significantly affected the daily mean exposures in residential areas located in the vicinity of the harbors.
- Published
- 2020
13. Simulation of the size-composition distribution of atmospheric nanoparticles over Europe
- Author
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D. Patoulias, C. Fountoukis, I. Riipinen, A. Asmi, M. Kulmala, S. N. Pandis, Tampere University, Physics, Aerosol-Cloud-Climate -Interactions (ACCI), INAR Physics, and Institute for Atmospheric and Earth System Research (INAR)
- Subjects
Atmospheric Science ,CONDENSATION NUCLEI PRODUCTION ,010504 meteorology & atmospheric sciences ,Particle number ,Chemical transport model ,Mean squared error ,NUMBER CONCENTRATIONS ,AIR-QUALITY ,116 Chemical sciences ,Nanoparticle ,010501 environmental sciences ,Atmospheric sciences ,114 Physical sciences ,01 natural sciences ,lcsh:Chemistry ,SULFURIC-ACID ,SECONDARY ORGANIC AEROSOL ,CHEMICAL-TRANSPORT MODEL ,PARTICLE FORMATION ,Ultrafine particle ,NUCLEATION EVENTS ,Air quality index ,1172 Environmental sciences ,0105 earth and related environmental sciences ,221 Nanotechnology ,BASIS-SET APPROACH ,lcsh:QC1-999 ,Aerosol ,WILD-LAND FIRES ,lcsh:QD1-999 ,13. Climate action ,Environmental science ,Volatility (chemistry) ,lcsh:Physics - Abstract
PMCAMx-UF, a three-dimensional chemical transport model focusing on the simulation of the ultrafine particle size distribution and composition has been extended with the addition of the volatility basis set (VBS) approach for the simulation of organic aerosol (OA). The model was applied in Europe to quantify the effect of secondary semi-volatile organic vapors on particle number concentrations. The model predictions were evaluated against field observations collected during the PEGASOS 2012 campaign. The measurements included both ground and airborne measurements, from stations across Europe and a zeppelin measuring above Po Valley. The ground level concentrations of particles with a diameter larger than 100 nm (N100) were reproduced with a daily normalized mean error of 40 % and a daily normalized mean bias of −20 %. PMCAMx-UF tended to overestimate the concentration of particles with a diameter larger than 10 nm (N10) with a daily normalized mean bias of 75 %. The model was able to reproduce, within a factor of 2, 85 % of the N10 and 75 % of the N100 zeppelin measurements above ground. The condensation of organics led to an increase (50 %–120 %) in the N100 concentration mainly in central and northern Europe, while the N10 concentration decreased by 10 %–30 %. Including the VBS in PMCAMx-UF improved its ability to simulate aerosol number concentration compared to simulations neglecting organic condensation on ultrafine particles.
- Published
- 2018
14. Atmospheric new particle formation from sulfuric acid and amines in a Chinese megacity
- Author
-
Jianmin Chen, Markku Kulmala, Fuhai Geng, Xin Yang, Heikki Junninen, Bowen Zhang, Hangfei Chen, Douglas R. Worsnop, Lei Yao, Dongfang Wang, Jun Zheng, Olga Garmash, Tuukka Petäjä, Mikael Ehn, Mingyi Wang, Hongli Wang, Jenni Kontkanen, Li Li, Qingyan Fu, Mikko Sipilä, Xinke Wang, Chao Yan, Pauli Paasonen, Lin Wang, F. Bianchi, Veli-Matti Kerminen, Yiqun Lu, Stephany Buenrostro Mazon, Liping Qiao, Shan Xiao, Institute for Atmospheric and Earth System Research (INAR), Aerosol-Cloud-Climate -Interactions (ACCI), INAR Physics, and Polar and arctic atmospheric research (PANDA)
- Subjects
010504 meteorology & atmospheric sciences ,NUMBER CONCENTRATIONS ,116 Chemical sciences ,Nucleation ,010501 environmental sciences ,114 Physical sciences ,01 natural sciences ,Ammonia ,chemistry.chemical_compound ,SIZE DISTRIBUTION ,Cluster (physics) ,EMISSIONS ,1172 Environmental sciences ,0105 earth and related environmental sciences ,AMMONIA ,Multidisciplinary ,Condensation ,Sulfuric acid ,TIME ,Aerosol ,OXIDIZED ORGANIC-MOLECULES ,Chemical engineering ,chemistry ,YANGTZE-RIVER DELTA ,13. Climate action ,GROWTH ,Particle ,AEROSOL NUCLEATION ,Sink (computing) ,CLUSTERS - Abstract
Atmospheric new particle formation (NPF) is an important global phenomenon that is nevertheless sensitive to ambient conditions. According to both observation and theoretical arguments, NPF usually requires a relatively high sulfuric acid (H2SO4) concentration to promote the formation of new particles and a low preexisting aerosol loading to minimize the sink of new particles. We investigated NPF in Shanghai and were able to observe both precursor vapors (H2SO4) and initial clusters at a molecular level in a megacity. High NPF rates were observed to coincide with several familiar markers suggestive of H2SO4-dimethylamine (DMA)water (H2O) nucleation, including sulfuric acid dimers and H2SO4-DMA clusters. In a cluster kinetics simulation, the observed concentration of sulfuric acid was high enough to explain the particle growth to similar to 3 nanometers under the very high condensation sink, whereas the subsequent higher growth rate beyond this size is believed to result fromthe added contribution of condensing organic species. These findings will help in understanding urban NPF and its air quality and climate effects, as well as in formulating policies to mitigate secondary particle formation in China.
- Published
- 2018
15. Atmospheric new particle formation at the research station Melpitz, Germany: connection with gaseous precursors and meteorological parameters
- Author
-
J. Größ, A. Hamed, A. Sonntag, G. Spindler, H. E. Manninen, T. Nieminen, M. Kulmala, U. Hõrrak, C. Plass-Dülmer, A. Wiedensohler, W. Birmili, and Department of Physics
- Subjects
Atmospheric Science ,010504 meteorology & atmospheric sciences ,Particle number ,FORMATION EVENTS ,NUMBER CONCENTRATIONS ,Nucleation ,CENTRAL-EUROPE ,010501 environmental sciences ,Atmospheric sciences ,01 natural sciences ,114 Physical sciences ,CLOUD CONDENSATION NUCLEI ,Troposphere ,lcsh:Chemistry ,chemistry.chemical_compound ,SULFURIC-ACID ,Cloud condensation nuclei ,NUCLEATION EVENTS ,Sulfur dioxide ,0105 earth and related environmental sciences ,CONTINENTAL BOUNDARY-LAYER ,AEROSOL-SIZE DISTRIBUTIONS ,Sulfuric acid ,lcsh:QC1-999 ,Aerosol ,Boundary layer ,chemistry ,lcsh:QD1-999 ,13. Climate action ,Environmental science ,LONG-TERM OBSERVATIONS ,lcsh:Physics ,AIR ION SPECTROMETER - Abstract
This paper revisits the atmospheric new particle formation (NPF) process in the polluted Central European troposphere, focusing on the connection with gas-phase precursors and meteorological parameters. Observations were made at the research station Melpitz (former East Germany) between 2008 and 2011 involving a neutral cluster and air ion spectrometer (NAIS). Particle formation events were classified by a new automated method based on the convolution integral of particle number concentration in the diameter interval 2–20 nm. To study the relevance of gaseous sulfuric acid as a precursor for nucleation, a proxy was derived on the basis of direct measurements during a 1-month campaign in May 2008. As a major result, the number concentration of freshly produced particles correlated significantly with the concentration of sulfur dioxide as the main precursor of sulfuric acid. The condensation sink, a factor potentially inhibiting NPF events, played a subordinate role only. The same held for experimentally determined ammonia concentrations. The analysis of meteorological parameters confirmed the absolute need for solar radiation to induce NPF events and demonstrated the presence of significant turbulence during those events. Due to its tight correlation with solar radiation, however, an independent effect of turbulence for NPF could not be established. Based on the diurnal evolution of aerosol, gas-phase, and meteorological parameters near the ground, we further conclude that the particle formation process is likely to start in elevated parts of the boundary layer rather than near ground level.
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- 2018
16. The effects of number and mass concentration of aerosol components on scattering coefficients in Xianghe, southeast of Beijing, China – A case study.
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Zou, Jianan, Cao, Qimin, Gao, Wenkang, Liu, Zirui, Wang, Honglei, Hu, Bo, and Wang, Yuesi
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MASS spectrometers , *TIME-of-flight mass spectrometry , *AEROSOLS , *SECONDARY ion mass spectrometry , *BIOMASS burning , *LIGHT scattering , *PARTICLE size distribution , *CHEMICAL ionization mass spectrometry - Abstract
Atmospheric visibility is closely correlated to atmospheric extinction, which is directly affected by water vapour and the presence of aerosols. To quantitatively analyse the effect of chemical composition and size distribution of aerosols on the scattering coefficients, atmospheric samples were collected at Xianghe Station, North China Plain, in December 2018. The concentration of non-refractory chemical components, measured via high-resolution time-of-flight aerosol mass spectrometry, was the highest in the 'Low visibility stage (L1)', with an average value of 77.7 μg m−3, wherein the mass concentration of organic matter accounted for 36.5%, and that of three secondary inorganic aerosols accounted for 57.4%. The scattering coefficients measured using the nephelometer and those calculated based on organic matter, sulphate, nitrate, and ammonium were largely the same, and the Pearson correlation was up to 0.82. A single-particle aerosol mass spectrometer was used to measure the vacuum aerodynamic diameter and chemical composition of a single particle. The extinction contribution proportions of combustion sources and biomass burning sources were 45.0% and 36.4%, which decreased by 3.2% and 4.9%, respectively, compared with the number concentration proportion of these sources (46.5% and 38.3%, respectively); this is related to the fact that the composition of these sources, contained more optically absorbent substances, will cause a drop in the scattering coefficients. Therefore, we further analyzed the source apportionment of aerosol optical scattering based on its composition and particle size distribution, which was able to provide guidance for controlling which pollutant emission will reduce the optical scattering value of aerosol during low visibility. ● Obtained physical and chemical information of aerosol sources, based on single particles. ● The growth of SIAs and SOAs would occur synchronically in a certain environment. ● Extinction contribution proportion of combustion and biomass burning sources was 45.0% and 36.4%, respectively. [ABSTRACT FROM AUTHOR]
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- 2022
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17. Ground-fixed and on-board measurements of nanoparticles in the wake of a moving vehicle
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Carpentieri, Matteo and Kumar, Prashant
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NANOPARTICLES , *PARTICLE size distribution , *DIESEL automobiles , *SPECTROMETERS , *BIOACCUMULATION , *DISPERSION (Chemistry) , *NUCLEATION , *EXPERIMENTAL design - Abstract
Abstract: An integrated experimental methodology has been applied to measure number and size distributions of particles in the 5–560 nm size range in the wake of a diesel car running at different speeds. Measurements were made at both ground-fixed (0.10 and 0.25 m above the ground level) and on-board (in 12 different sampling locations behind the moving car) measurement configurations using a fast response differential mobility spectrometer (Cambustion DMS50) with a sampling frequency up to 10 Hz. Results from both the experimental campaigns were analysed to understand the dynamics, dispersion and transport of nanoparticle emissions in the wake of a moving vehicle. Temporal changes in results were divided into three main stages (pre-evolution, evolution and post-evolution) after the release of exhaust emissions from the tailpipe. Evolution stage is of most interest where all the changes to particle number and size distribution occurred. Up to four evolution sub-stages were observed, each showing distinct evolution patterns of particle size distributions, depending on the particular experimental run. In agreement with previous studies, dilution was found to be the dominant process throughout all the evolution stages. The first evolution sub-stage was common to all the measurements, and consisted of an initial particle number concentrations and distributions change due to rapid (less than 1 s) nucleation followed by a rapid increase of accumulation mode particle number concentrations. After this first sub-stage the presence of vehicle wake with recirculating particles and the possible influence of other transformation processes lead to complex interactions. Results from the two experimental datasets clearly confirm the presence of two separate groups of particles: (i) new particles, which are freshly emitted and come directly from the tailpipe and (ii) relatively aged particles, which are entrained within the recirculation vortices of the vehicle wake and reside there for a longer time. The two groups have different characteristics and interact with each other. This interaction has often been overlooked in past studies about local scale dispersion of nanoparticle from moving vehicles. [Copyright &y& Elsevier]
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- 2011
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18. Size distributions of aerosol number concentrations and water-soluble constituents in Toyama, Japan: A comparison of the measurements during Asian dust period with non-dust period
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Watanabe, Koichi, Kasuga, Hisashi, Yamada, Yuko, and Kawakami, Tomonori
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PARTICLES , *ATTENTION , *ATMOSPHERIC circulation , *STAKEHOLDERS - Abstract
Abstract: Size-separated aerosol number concentrations and water-soluble constituents were measured in Toyama, the Hokuriku district, near the coast of the Japan Sea, during the spring and summer in 2003. The number concentrations of coarse particles were significantly high in April, which was due to Asian dust events called Kosa in Japanese. Particulate nssCa2+, which is mostly present in the coarse-mode particles, was significantly high in April. On the other hand, the concentrations of NH4 + and nssSO4 2−, which mainly exist as the accumulation-mode particles were not high in April. The mass-size distributions of water-soluble constituents were compared with the size-separated number concentrations of particles. Backward trajectory analysis was also employed to examine the transport process of the air mass in Toyama. [Copyright &y& Elsevier]
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- 2006
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19. Ultrafine particles and PM 2.5 in the air of cities around the world: Are they representative of each other?
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Josef Cyrys, Harri Portin, Tuukka Petäjä, Michał Kowalski, Li Li, Constantinos Sioutas, Luke D. Knibbs, Markku Kulmala, Maurizio Manigrasso, Greg J. Evans, David C. S. Beddows, Krista Luoma, Roy M. Harrison, Hilkka Timonen, Helen Thompson, Pasquale Avino, Annette Peters, Mahmudur Rahman, Luca Ferrero, Jarkko V. Niemi, Mandana Mazaheri, Xavier Querol, Lidia Morawska, Wei Nei, Mohammad H. Sowlat, Liping Qiao, Aijun Ding, Cristina Reche, Cheol-Heon Jeong, Alma Lorelei de Jesus, Giorgio Buonano, de Jesus, A, Rahman, M, Mazaheri, M, Thompson, H, Knibbs, L, Jeong, C, Evans, G, Nei, W, Ding, A, Qiao, L, Li, L, Portin, H, Niemi, J, Timonen, H, Luoma, K, Petaja, T, Kulmala, M, Kowalski, M, Peters, A, Cyrys, J, Ferrero, L, Manigrasso, M, Avino, P, Buonano, G, Reche, C, Querol, X, Beddows, D, Harrison, R, Sowlat, M, Sioutas, C, Morawska, L, Department of Physics, Reche, Cristina, Querol, Xavier, Reche, Cristina [0000-0002-3387-3989], and Querol, Xavier [0000-0002-6549-9899]
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010504 meteorology & atmospheric sciences ,Particle number ,NUMBER CONCENTRATIONS ,SEASONAL-VARIATION ,116 Chemical sciences ,Particle number concentration ,PM 2.5 ,Urban aerosol ,PM2.5 ,010501 environmental sciences ,CHEMICAL-COMPOSITION ,114 Physical sciences ,complex mixtures ,01 natural sciences ,Urban Aerosol ,Particle Number Concentration ,Pm2.5 ,Particle mass ,Urban background ,11. Sustainability ,Ultrafine particle ,Aerodynamic diameter ,Mass concentration (chemistry) ,SPATIAL VARIATION ,Air quality index ,1172 Environmental sciences ,lcsh:Environmental sciences ,0105 earth and related environmental sciences ,General Environmental Science ,lcsh:GE1-350 ,AEROSOL-SIZE DISTRIBUTIONS ,Environmental engineering ,LOS-ANGELES ,SOURCE APPORTIONMENT ,13. Climate action ,CHIM/12 - CHIMICA DELL'AMBIENTE E DEI BENI CULTURALI ,TEMPORAL VARIATIONS ,Air quality ,MASS CONCENTRATIONS ,Environmental science ,FINE PARTICULATE MATTER ,Linear correlation - Abstract
Can mitigating only particle mass, as the existing air quality measures do, ultimately lead to reduction in ultrafine particles (UFP)? The aim of this study was to provide a broader urban perspective on the relationship between UFP, measured in terms of particle number concentration (PNC) and PM2.5 (mass concentration of particles with aerodynamic diameter < 2.5 μm) and factors that influence their concentrations. Hourly average PNC and PM2.5 were acquired from 10 cities located in North America, Europe, Asia, and Australia over a 12-month period. A pairwise comparison of the mean difference and the Kolmogorov-Smirnov test with the application of bootstrapping were performed for each city. Diurnal and seasonal trends were obtained using a generalized additive model (GAM). The particle number to mass concentration ratios and the Pearson's correlation coefficient were calculated to elucidate the nature of the relationship between these two metrics. Results show that the annual mean concentrations ranged from 8.0 × 103 to 19.5 × 103 particles·cm−3 and from 7.0 to 65.8 μg·m−3 for PNC and PM2.5, respectively, with the data distributions generally skewed to the right, and with a wider spread for PNC. PNC showed a more distinct diurnal trend compared with PM2.5, attributed to the high contributions of UFP from vehicular emissions to PNC. The variation in both PNC and PM2.5 due to seasonality is linked to the cities' geographical location and features. Clustering the cities based on annual median concentrations of both PNC and PM2.5 demonstrated that a high PNC level does not lead to a high PM2.5, and vice versa. The particle number-to-mass ratio (in units of 109 particles·μg−1) ranged from 0.14 to 2.2, >1 for roadside sites and, “GEMMA Center in the framework of Project MIUR – Dipartimenti di Eccellenza 2018–2022” funding for measurements in Milan site. Appendix A
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- 2019
20. Differences in removal rates of virgin/decayed microplastics, viruses, activated carbon, and kaolin/montmorillonite clay particles by coagulation, flocculation, sedimentation, and rapid sand filtration during water treatment.
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Nakazawa, Yoshifumi, Abe, Taketo, Matsui, Yoshihiko, Shinno, Koki, Kobayashi, Sakiko, Shirasaki, Nobutaka, and Matsushita, Taku
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SAND filtration (Water purification) , *PLASTIC marine debris , *COAGULATION , *KAOLIN , *WATER treatment plants , *ACTIVATED carbon , *WATER purification , *MICROPLASTICS - Abstract
• Activated carbon in water treatment plant sand filtrate was 40−200 particles/Ml. • The order of removal rates were activated carbon >> viruses >> clay ≈ microplastics. • Coagulation-sedimentation accounted for most virus, clay, and microplastic removal. • These particles were removed by rapid sand filtration less than by activated carbon. • Weathering changed the zeta potential and removal of microplastics a little. One of the main purposes of drinking water treatment is to reduce turbidity originating from clay particles. Relatively little is known about the removal of other types of particles, including conventionally sized powdered activated carbon (PAC) and superfine PAC (SPAC), which are intentionally added during the treatment process; microplastic particles; and viruses. To address this knowledge gap, we conducted a preliminary investigation in full-scale water treatment plants and then studied the removal of these particles during coagulation-flocculation, sedimentation, and rapid sand filtration (CSF) in bench-scale experiments in which these particles were present together. Numbers of all target particles were greatly decreased by coagulation-flocculation and sedimentation (CS). Subsequent rapid sand filtration greatly reduced the concentrations of PAC and SPAC but not the concentrations of viruses, microplastic particles, and clay particles. Overall removal rates by CSF were 4.6 logs for PAC and SPAC, 3.5 logs for viruses, 2.9 logs for microplastics, and 2.8 logs for clay. The differences in removals were not explained by particle sizes or zeta potentials. However, for clays, PAC and SPAC, for which the particle size distributions were wide, smaller particles were less efficiently removed. The ratios of both clay to PAC and clay to SPAC particles increased greatly after rapid sand filtration because removal rates of PAC and SPAC particles were about 2 logs higher than removal rates of clay particles. The trend of greater reduction of PAC concentrations than turbidity was confirmed by measurements made in 14 full-scale water purification plants in which residual concentrations of PAC in treated water were very low, 40–200 particles/mL. Clay particles therefore accounted for most of the turbidity in sand filtrate, even though PAC was employed. The removal rate of microplastic particles was comparable to that of clays. Sufficient turbidity removal would therefore provide comparable removal of microplastics. We investigated the effect of mechanical/photochemical weathering on the removal of microplastics via CSF. Photochemical weathering caused a small increment in the removal rate of microplastics during CS but a small reduction in the removal rate of microplastics during rapid sand filtration; mechanical weathering decreased the removal rate via CS but increased the removal rate via rapid sand filtration. The changes of removal of microplastics might have been caused by changes of their zeta potential. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2021
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21. Implementation of state-of-the-art ternary new-particle formation scheme to the regional chemical transport model PMCAMx-UF in Europe
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Baranizadeh, E, Murphy, BN, Julin, J, Falahat, S, Reddington, CL, Arola, A, Ahlm, L, Mikkonen, S, Fountoukis, C, Patoulias, D, Minikin, A, Hamburger, T, Laaksonen, A, Pandis, SN, Vehkamäki, H, Lehtinen, KEJ, Riipinen, I, Department of Physics, and INAR Physics
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aerosol ,NUMBER CONCENTRATIONS ,BOUNDARY-LAYER NUCLEATION ,AIR-QUALITY ,lcsh:QE1-996.5 ,Atmosphärische Spurenstoffe ,Annan geovetenskap och miljövetenskap ,QUALITY INTERACTIONS EUCAARI ,114 Physical sciences ,WILD-LAND FIRES ,lcsh:Geology ,SULFURIC-ACID ,ATMOSPHERIC PARTICLES ,new particle formation ,INTEGRATING AEROSOL RESEARCH ,SIZE DISTRIBUTION ,chemical transport model ,EUCAARI ,GLOBAL SCALES ,Other Earth and Related Environmental Sciences - Abstract
The particle formation scheme within PMCAMx-UF, a three-dimensional chemical transport model, was updated with particle formation rates for the ternary H2SO4–NH3–H2O pathway simulated by the Atmospheric Cluster Dynamics Code (ACDC) using quantum chemical input data. The model was applied over Europe for May 2008, during which the EUCAARI-LONGREX (European Aerosol Cloud Climate and Air Quality Interactions–Long-Range Experiment) campaign was carried out, providing aircraft vertical profiles of aerosol number concentrations. The updated model reproduces the observed number concentrations of particles larger than 4 nm within 1 order of magnitude throughout the atmospheric column. This agreement is encouraging considering the fact that no semi-empirical fitting was needed to obtain realistic particle formation rates. The cloud adjustment scheme for modifying the photolysis rate profiles within PMCAMx-UF was also updated with the TUV (Tropospheric Ultraviolet and Visible) radiative-transfer model. Results show that, although the effect of the new cloud adjustment scheme on total number concentrations is small, enhanced new-particle formation is predicted near cloudy regions. This is due to the enhanced radiation above and in the vicinity of the clouds, which in turn leads to higher production of sulfuric acid. The sensitivity of the results to including emissions from natural sources is also discussed.
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- 2016
22. Urban Aerosol Particle Size Characterization in Eastern Mediterranean Conditions
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Lubna Dada, Simo Hakala, Tareq Hussein, Markku Kulmala, Tuukka Petäjä, Air quality research group, Department of Physics, Institute for Atmospheric and Earth System Research (INAR), and INAR Physics
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CHARACTERIZING MINERAL DUSTS ,Atmospheric Science ,Materials science ,010504 meteorology & atmospheric sciences ,Particle number ,BACKGROUND ATMOSPHERE ,NUMBER CONCENTRATIONS ,010501 environmental sciences ,Environmental Science (miscellaneous) ,Atmospheric sciences ,114 Physical sciences ,01 natural sciences ,Wind speed ,PARTICULATE MATTER ,Ultrafine particle ,Relative humidity ,diurnal ,COASTAL CITY JEDDAH ,modal structure ,0105 earth and related environmental sciences ,ULTRAFINE PARTICLES ,particle number size distribution ,coarse ,meteorological effect ,AIR-POLLUTION ,seasonal ,Aerosol ,13. Climate action ,submicron ,BLACK CARBON ,Particle ,Particle size ,Geometric mean ,PHYSICAL-CHARACTERISTICS ,TRANSPORT MICROENVIRONMENTS - Abstract
Characterization of urban particle number size distribution (PNSD) has been rarely reported/performed in the Middle East. Therefore, we aimed at characterizing the PNSD (0.01&ndash, 10 µ, m) in Amman as an example for an urban Middle Eastern environment. The daily mean submicron particle number concentration (PNSub) was 6.5 ×, 103&ndash, 7.7 ×, 104 cm&minus, 3 and the monthly mean coarse mode particle number concentration (PNCoarse) was 0.9&ndash, 3.8 cm&minus, 3 and both had distinguished seasonal variation. The PNSub also had a clear diurnal and weekly cycle with higher concentrations on workdays (Sunday&ndash, Thursday, over 3.3 ×, 3) than on weekends (below 2.7 ×, 3). The PNSub constitute of 93% ultrafine fraction (diameter <, 100 nm). The mean particle number size distributions was characterized with four well-separated submicron modes (Dpg,I, Ni): nucleation (22 nm, 9.4 ×, 103 cm&minus, 3), Aitken (62 nm, 3.9 ×, 3), accumulation (225 nm, 158 cm&minus, 3), and coarse (2.23 µ, m, 1.2 cm&minus, 3) in addition to a mode with small geometric mean diameter (GMD) that represented the early stage of new particle formation (NPF) events. The wind speed and temperature had major impacts on the concentrations. The PNCoarse had a U-shape with respect to wind speed and PNSub decreased with wind speed. The effect of temperature and relative humidity was complex and require further investigations.
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- 2019
23. A European aerosol phenomenology – 6: scattering properties of atmospheric aerosol particles from 28 ACTRIS sites
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M. Pandolfi, L. Alados-Arboledas, A. Alastuey, M. Andrade, C. Angelov, B. Artiñano, J. Backman, U. Baltensperger, P. Bonasoni, N. Bukowiecki, M. Collaud Coen, S. Conil, E. Coz, V. Crenn, V. Dudoitis, M. Ealo, K. Eleftheriadis, O. Favez, P. Fetfatzis, M. Fiebig, H. Flentje, P. Ginot, M. Gysel, B. Henzing, A. Hoffer, A. Holubova Smejkalova, I. Kalapov, N. Kalivitis, G. Kouvarakis, A. Kristensson, M. Kulmala, H. Lihavainen, C. Lunder, K. Luoma, H. Lyamani, A. Marinoni, N. Mihalopoulos, M. Moerman, J. Nicolas, C. O'Dowd, T. Petäjä, J.-E. Petit, J. M. Pichon, N. Prokopciuk, J.-P. Putaud, S. Rodríguez, J. Sciare, K. Sellegri, E. Swietlicki, G. Titos, T. Tuch, P. Tunved, V. Ulevicius, A. Vaishya, M. Vana, A. Virkkula, S. Vratolis, E. Weingartner, A. Wiedensohler, P. Laj, Institute of Environmental Assessment and Water Research (IDAEA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Universidad de Granada = University of Granada (UGR), Universidad Mayor de San Andrés (UMSA), Bulgarian Academy of Sciences (BAS), Centro de Investigaciones Energéticas Medioambientales y Tecnológicas [Madrid] (CIEMAT), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Finnish Meteorological Institute (FMI), Laboratory of Atmospheric Chemistry [Paul Scherrer Institute] (LAC), Paul Scherrer Institute (PSI), CNR Institute of Atmospheric Sciences and Climate (ISAC), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Federal Office of Meteorology and Climatology MeteoSwiss, Observatoire Pérenne de l'Environnement, Agence Nationale pour la Gestion des Déchets Radioactifs (ANDRA), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ADDAIR Sté (France), Center for Physical Sciences and Technology [Vilnius] (FTMC), National Centre for Scientific Research Demokritos, Institut National de l'Environnement Industriel et des Risques (INERIS), Norwegian Institute for Air Research (NILU), Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), The Netherlands Organisation for Applied Scientific Research (TNO), University of Crete [Heraklion] (UOC), National Observatory of Athens (NOA), Lund University [Lund], Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Chimie Atmosphérique Expérimentale (CAE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), Leibniz Institute for Tropospheric Research (TROPOS), Vikram Sarabhai Space Ctr, European Commission, University of Granada [Granada], University of Helsinki, Consiglio Nazionale delle Ricerche (CNR), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), INAR Physics, and Department of Physics
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Atmospheric Science ,Angstrom exponent ,010504 meteorology & atmospheric sciences ,Mass concentrations ,Seasonal variation ,NUMBER CONCENTRATIONS ,Aerosol sources ,radiative properties ,010501 environmental sciences ,black carbon ,western mediterranean basin ,01 natural sciences ,lcsh:Chemistry ,free troposphere ,saharan dust ,Factorization ,Physics::Atmospheric and Oceanic Physics ,Positive matrix ,Particle size ,Particulates ,lcsh:QC1-999 ,LIGHT-SCATTERING ,optical-properties ,in-situ ,Climatology ,[SDE]Environmental Sciences ,MEDITERRANEAN BASIN ,Phenomenology ,Environment & Sustainability ,Particle light scattering ,Atmospheric aerosol ,Scattering properties ,Aerosol particle ,Backscatter ,Urbanisation ,Mineral dust ,Environment ,114 Physical sciences ,Aerosol formation ,medicine ,Aerosol ,1172 Environmental sciences ,0105 earth and related environmental sciences ,particulate matter ,Scattering ,Aerosol properties ,integrating nephelometer ,Seasonality ,medicine.disease ,Concentration (composition) ,lcsh:QD1-999 ,Arctic ,13. Climate action ,regional background sites ,Environmental science ,Particulate matter ,Aerosol property ,lcsh:Physics - 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 intraannual 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(s) 2018., Acknowledgements. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 654109, ACTRIS (project no. 262254), ACTRIS-PPP (project no. 739530). We thank the International Foundation High Altitude Research Stations JFJ (Jungfraujoch) and Gornergrat (HFSJG), which made it possible to carry out the experiments at the High Altitude Research JFJ Station and the support of MeteoSwiss within the Swiss programme of the Global Atmosphere Watch (GAW) of the WMO. The MAD (Madrid) station is co-financed by the PROACLIM (CGL2014-52877-R) project. The SMR (Hyytiälä) station acknowledges BACCHUS (project no. 603445), CRAICC (project no. 26060) and the Academy of Finland (project no. 3073314). The UGR (Granada) station is co-financed by the Spanish Ministry of Economy and Competitiveness through project CGL2016-81092-R. Measurements at MSY (Montseny) and MSA (Montsec) stations were supported by the MINECO (Spanish Ministry of Economy, Industry and Competitiveness) and FEDER funds under the PRISMA project (CGL2012-39623-C02/00) and under the HOUSE project (CGL2016-78594-R), by the MAGRAMA (Spanish Ministry of Agriculture, Food and Environment) and by the Generalitat de Catalunya (AGAUR 2014 SGR33, AGAUR 2017 SGR41 and the DGQA). Measurements at IZO (Izaña) were supported by the AEROATLAN project (CGL2015-17 66229-P), co-funded by the Ministry of Economy and Competitiveness of Spain and the European Regional Development Fund. Station KOS (Košetice) is supported by the Ministry of Education, Youth and Sports of the Czech Republic within the project to support the national research infrastructure ACTRIS – participation of the Czech Republic (ACTRIS-CZ – LM2015037). Measurements at PUY (Puy de Dôme) were partly supported by CNRS-INSU, University Clermont-Auvergne, OPGC and the french CLAP programme. The PAL (Pallas) station acknowledges KONE Foundation, Academy of Finland (project no. 269095 and no. 296302). CHC (Mt Chacaltaya) station received support from Institut de Recherche pour le Développement (IRD) under both Jeune Equipe programme attributed to LFA and support to ACTRIS-FR programme. CHC received grants from Labex OSUG@2020 (Investissements d’avenir – ANR10 LABX56). Marco Pandolfi is funded by a Ramón y Cajal Fellowship (RYC-2013-14036) awarded by the Spanish Ministry of Economy and Competitiveness. The authors would like to express their gratitude to David Carslaw and Karl Ropkins for providing the OpenAir software used in this paper (Carslaw and Ropkins, 2012; Carslaw, 2012). We also thank the co-editor Andreas Petzold and two anonymous reviewers for their constructive comments.
- Published
- 2018
24. Mobile monitoring for mapping spatial variation in urban air quality: Development and validation of a methodology based on an extensive dataset
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Jan Theunis, Dick Botteldooren, Joris Van den Bossche, Jan Peters, Jan Verwaeren, and Bernard De Baets
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Atmospheric Science ,Meteorology ,NUMBER CONCENTRATIONS ,ULTRAFINE PARTICLE CONCENTRATIONS ,High resolution ,POLLUTANT CONCENTRATIONS ,Representativeness heuristic ,Black carbon ,PARTICULATE MATTER ,AEROSOL LIGHT-ABSORPTION ,Urban air quality ,Image resolution ,Air quality index ,General Environmental Science ,Remote sensing ,FINE PARTICLES ,Data processing ,Spatial variation ,PERSONAL EXPOSURE ,Truncated mean ,Mobile monitoring ,LOS-ANGELES ,Mapping ,Earth and Environmental Sciences ,Snapshot (computer storage) ,Environmental science ,Spatial variability ,TRANSPORT MICROENVIRONMENTS - Abstract
Mobile monitoring is increasingly used as an additional tool to acquire air quality data at a high spatial resolution. However, given the high temporal variability of urban air quality, a limited number of mobile measurements may only represent a snapshot and not be representative. In this study, the impact of this temporal variability on the representativeness is investigated and a methodology to map urban air quality using mobile monitoring is developed and evaluated. A large set of black carbon (BC) measurements was collected in Antwerp, Belgium, using a bicycle equipped with a portable BC monitor (micro-aethalometer). The campaign consisted of 256 and 96 runs along two fixed routes (2 and 5 km long). Large gradients over short distances and differences up to a factor of 10 in mean BC concentrations aggregated at a resolution of 20 m are observed. Mapping at such a high resolution is possible, but a lot of repeated measurements are required. After computing a trimmed mean and applying background normalisation, depending on the location 24–94 repeated measurement runs (median of 41) are required to map the BC concentrations at a 50 m resolution with an uncertainty of 25%. When relaxing the uncertainty to 50%, these numbers reduce to 5–11 (median of 8) runs. We conclude that mobile monitoring is a suitable approach for mapping the urban air quality at a high spatial resolution, and can provide insight into the spatial variability that would not be possible with stationary monitors. A careful set-up is needed with a sufficient number of repetitions in relation to the desired reliability and spatial resolution. Specific data processing methods such as background normalisation and event detection have to be applied.
- Published
- 2015
25. Land use regression models for Ultrafine Particles in six European areas
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van Nunen, Erik, Vermeulen, Roel, Tsai, Ming-Yi, Probst-Hensch, Nicole, Ineichen, Alex, Davey, Mark E, Imboden, Medea, Ducret-Stich, Regina, Naccarati, Alessio, Raffaele, Daniela, Ranzi, Andrea, Ivaldi, Cristiana, Galassi, Claudia, Nieuwenhuijsen, Mark J, Curto, Ariadna, Donaire-Gonzalez, David, Cirach, Marta, Chatzi, Leda, Kampouri, Mariza, Vlaanderen, Jelle, Meliefste, Kees, Buijtenhuijs, Daan, Brunekreef, Bert, Morley, David, Vineis, Paolo, Gulliver, John, Hoek, Gerard, dIRAS RA-2, LS IRAS EEPI GRA (Gezh.risico-analyse), LS IRAS EEPI ME (Milieu epidemiologie), Dep IRAS, dIRAS RA-I&I RA, Commission of the European Communities, dIRAS RA-2, LS IRAS EEPI GRA (Gezh.risico-analyse), LS IRAS EEPI ME (Milieu epidemiologie), Dep IRAS, and dIRAS RA-I&I RA
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Technology ,010504 meteorology & atmospheric sciences ,Intraclass correlation ,NUMBER CONCENTRATIONS ,Air pollution ,Environmental Sciences & Ecology ,010501 environmental sciences ,Land use regression ,medicine.disease_cause ,NO2 ,Partícules (Matèria) ,01 natural sciences ,Article ,Engineering ,Air pollutants ,PARTICULATE MATTER ,Air Pollution ,Anàlisi de regressió ,Ultrafine particle ,MD Multidisciplinary ,medicine ,Environmental Chemistry ,SPATIAL VARIATION ,INTERNATIONAL AIRPORT ,NITROGEN-DIOXIDE ,0105 earth and related environmental sciences ,Air Pollutants ,Science & Technology ,Engineering, Environmental ,ESCAPE PROJECT ,General Chemistry ,AIR-POLLUTION ,Stepwise regression ,Models, Theoretical ,Particles ,Geography ,PM2.5 ABSORBENCY ,BLACK CARBON ,Spatial variability ,Regression analysis ,Cartography ,Life Sciences & Biomedicine ,Environmental Sciences ,Environmental Monitoring - Abstract
Long-term ultrafine particle (UFP) exposure estimates at a fine spatial scale are needed for epidemiological studies. Land use regression (LUR) models were developed and evaluated for six European areas based on repeated 30 min monitoring following standardized protocols. In each area; Basel (Switzerland), Heraklion (Greece), Amsterdam, Maastricht, and Utrecht ("The Netherlands"), Norwich (United Kingdom), Sabadell (Spain), and Turin (Italy), 160-240 sites were monitored to develop LUR models by supervised stepwise selection of GIS predictors. For each area and all areas combined, 10 models were developed in stratified random selections of 90% of sites. UFP prediction robustness was evaluated with the intraclass correlation coefficient (ICC) at 31-50 external sites per area. Models from Basel and The Netherlands were validated against repeated 24 h outdoor measurements. Structure and model R2 of local models were similar within, but varied between areas (e.g., 38-43% Turin; 25-31% Sabadell). Robustness of predictions within areas was high (ICC 0.73-0.98). External validation R2 was 53% in Basel and 50% in The Netherlands. Combined area models were robust (ICC 0.93-1.00) and explained UFP variation almost equally well as local models. In conclusion, robust UFP LUR models could be developed on short-term monitoring, explaining around 50% of spatial variance in longer-term measurements.
- Published
- 2017
26. Vertical Profiles of Pollution Particle Concentrations in the Boundary Layer above Paris (France) from the Optical Aerosol Counter LOAC Onboard a Touristic Balloon.
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Renard, Jean-Baptiste, Michoud, Vincent, and Giacomoni, Jérôme
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- *
PARTICULATE matter , *BOUNDARY layer (Aerodynamics) , *AIR pollution monitoring , *AIR quality monitoring , *AEROSOLS - Abstract
Atmospheric pollution by particulate matter represents a significant health risk and needs continuous monitoring by air quality networks that provide mass concentrations for PM10 and PM2.5 (particles with diameter smaller than 10 μm and 2.5 μm, respectively). We present here a new approach to monitor the urban particles content, using six years of aerosols number concentration measurements for particles in the 0.2−50 μm size range. These measurements are performed by the Light Optical Aerosols Counter (LOAC) instrument onboard the tethered touristic balloon "Ballon de Paris Generali", in Paris, France. Such measurements have allowed us first to detect at ground a seasonal variability in the particulate matter content, due to the origin of the particles (anthropogenic pollution, pollens), and secondly, to retrieve the mean evolution of particles concentrations with height above ground up to 150 m. Measurements were also conducted up to 300 m above ground during major pollution events. The vertical evolution of concentrations varies from one event to another, depending on the origin of the pollution and on the meteorological conditions. These measurements have shown the interest of performing particle number concentrations measurements for the air pollution monitoring in complement with regulatory mass concentrations measurement, to better evaluate the intensity of the pollution event and to better consider the effect of smallest particles, which are more dangerous for human health. [ABSTRACT FROM AUTHOR]
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- 2020
- Full Text
- View/download PDF
27. Exposure to ultrafine particles and respiratory hospitalisations in five European cities
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Thomas A. J. Kuhlbusch, Josef Cyrys, Giorgio Cattani, Steffen Loft, A. Massling, Timo Lanki, Evangelia Samoli, Frauke Hennig, Francesco Forastiere, Markku Kulmala, Massimo Stafoggia, Tom Bellander, Klea Katsouyanni, Bénédicte Jacquemin, Zorana Jovanovic Andersen, Aurelio Tobias, Tobías, Aurelio, and Tobías, Aurelio [0000-0001-6428-6755]
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Male ,Pediatrics ,010504 meteorology & atmospheric sciences ,NUMBER CONCENTRATIONS ,Air pollution ,CHILDREN ,010501 environmental sciences ,medicine.disease_cause ,01 natural sciences ,PARTICULATE MATTER ,ADMISSIONS ,11. Sustainability ,Ultrafine particle ,Epidemiology ,Pulmonary Medicine ,Medicine ,Poisson Distribution ,Respiratory system ,Child ,Temperature ,Regression analysis ,Environmental exposure ,Physik (inkl. Astronomie) ,Middle Aged ,3. Good health ,Europe ,Hospitalization ,FINE ,Child, Preschool ,symbols ,Regression Analysis ,Female ,PROJECT ,Environmental Monitoring ,Pulmonary and Respiratory Medicine ,Adult ,medicine.medical_specialty ,Adolescent ,symbols.namesake ,Young Adult ,Environmental health ,Air Pollution ,Humans ,Poisson regression ,Particle Size ,METAANALYSIS ,0105 earth and related environmental sciences ,Exposure assessment ,Aged ,business.industry ,MORTALITY ,Particulate air ,Infant, Newborn ,Infant ,Environmental Exposure ,AMBIENT AIR-POLLUTION ,EMERGENCY-ROOM VISITS ,13. Climate action ,Air quality ,business ,Particulate matter - Abstract
Epidemiological evidence on the associations between exposure to ultrafine particles (UFP), with aerodynamic electrical mobility diameters, We thank the Consorci Sanitari de Barcelona (Cat-Salut) for providing hospitalisation data for Barcelona and the Agencia Estatal de Meteorologia (Ministerio de Agricultura, Alimentación y Medio Ambiente) for providing the weather data for Spain. We thank the Finnish Meteorological Institute for providing the weather data for Finland and Helsinki Region Environmental Services Authority HSY for providing the air pollution (other than UFP) data for Helsinki, Finland. The study has been conducted as a collaborative effort of the UF&HEALTH Study Group. UF&HEALTH Study Group: S. Breitner, J. Cyrys, R. Hampel, F. Hennig, B. Hoffmann, T. Kuhlbusch; S. Lanzinger, A. Peters, U. Quass, A. Schneider, K. Wolf (Germany); E. Diapouli, K. Elefteriadis, K. Katsouyanni, E. Samoli, S. Vratolis (Greece); T. Ellermann, Z. Ivanovic-Andersen, S. Loft, A. Massling, C. Nordstrøm (Denmark); P.P. Aalto, M. Kulmala, T. Lanki, J. Pekkanen, P. Tiittanen, T. Yli-Tuomi (Finland); G. Cattani, A. Faustini, F. Forastiere, M. Inglessis, M. Renzi, M. Stafoggia (Italy); D. Agis, X. Basagaña, B. Jacquemin, N. Perez, J. Sunyer, A. Tobias (Spain); G. Bero-Bedada, T. Bellander (Sweden).
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- 2016
28. Impact of gas-to-particle partitioning approaches on the simulated radiative effects of biogenic secondary organic aerosol
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Dominick V. Spracklen, Kenneth S. Carslaw, Erik Swietlicki, Piers M. Forster, Ilona Riipinen, Paulo Artaxo, Graham Mann, S. D. D'Andrea, Luciana V. Rizzo, Markku Kulmala, Catherine E. Scott, Jeffrey R. Pierce, Kirsty J. Pringle, Alexandru Rap, and Department of Physics
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Atmospheric Science ,Chemical transport model ,NUMBER CONCENTRATIONS ,CCN CONCENTRATIONS ,Kinetic energy ,114 Physical sciences ,lcsh:Chemistry ,chemistry.chemical_compound ,SULFURIC-ACID ,GLOMAP-MODE ,CHEMICAL-TRANSPORT MODEL ,Radiative transfer ,medicine ,CLOUD DROPLET FORMATION ,NUCLEATION MODE PARTICLES ,Microphysics ,Chemistry ,GLOBAL CLIMATE MODELS ,BOUNDARY-LAYER ,Sulfuric acid ,medicine.disease ,lcsh:QC1-999 ,Aerosol ,Boundary layer ,lcsh:QD1-999 ,13. Climate action ,Chemical physics ,Environmental chemistry ,GROWTH ,lcsh:Physics ,Vapours - Abstract
The oxidation of biogenic volatile organic compounds (BVOCs) gives a range of products, from semi-volatile to extremely low-volatility compounds. To treat the interaction of these secondary organic vapours with the particle phase, global aerosol microphysics models generally use either a thermodynamic partitioning approach (assuming instant equilibrium between semi-volatile oxidation products and the particle phase) or a kinetic approach (accounting for the size dependence of condensation). We show that model treatment of the partitioning of biogenic organic vapours into the particle phase, and consequent distribution of material across the size distribution, controls the magnitude of the first aerosol indirect effect (AIE) due to biogenic secondary organic aerosol (SOA). With a kinetic partitioning approach, SOA is distributed according to the existing condensation sink, enhancing the growth of the smallest particles, i.e. those in the nucleation mode. This process tends to increase cloud droplet number concentrations in the presence of biogenic SOA. By contrast, an approach that distributes SOA according to pre-existing organic mass restricts the growth of the smallest particles, limiting the number that are able to form cloud droplets. With an organically mediated new particle formation mechanism, applying a mass-based rather than a kinetic approach to partitioning reduces our calculated global mean AIE due to biogenic SOA by 24 %. Our results suggest that the mechanisms driving organic partitioning need to be fully understood in order to accurately describe the climatic effects of SOA.
- Published
- 2015
29. Implementation of state-of-the-art ternary new-particle formation scheme to the regional chemical transport model PMCAMx-UF in Europe
- Abstract
The particle formation scheme within PMCAMx-UF, a three-dimensional chemical transport model, was updated with particle formation rates for the ternary H2SO4-NH3-H2O pathway simulated by the Atmospheric Cluster Dynamics Code (ACDC) using quantum chemical input data. The model was applied over Europe for May 2008, during which the EUCAARI-LONGREX (European Aerosol Cloud Climate and Air Quality Interactions-Long-Range Experiment) campaign was carried out, providing aircraft vertical profiles of aerosol number concentrations. The updated model reproduces the observed number concentrations of particles larger than 4 nm within 1 order of magnitude throughout the atmospheric column. This agreement is encouraging considering the fact that no semi-empirical fitting was needed to obtain realistic particle formation rates. The cloud adjustment scheme for modifying the photolysis rate profiles within PMCAMx-UF was also updated with the TUV (Tropospheric Ultraviolet and Visible) radiative-transfer model. Results show that, although the effect of the new cloud adjustment scheme on total number concentrations is small, enhanced new-particle formation is predicted near cloudy regions. This is due to the enhanced radiation above and in the vicinity of the clouds, which in turn leads to higher production of sulfuric acid. The sensitivity of the results to including emissions from natural sources is also discussed.
- Published
- 2016
30. Spatial and vertical extent of nucleation events in the Midwestern USA: insights from the Nucleation In ForesTs (NIFTy) experiment
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Rebecca Jane Barthelmie, Lise Lotte Sørensen, Tuukka Petäjä, Sara C. Pryor, Philip K. Hopke, and J. G. McGrath
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Atmospheric Science ,010504 meteorology & atmospheric sciences ,Particle number ,Mixed layer ,Cloud cover ,Nucleation ,010501 environmental sciences ,growth-rates ,Atmospheric sciences ,01 natural sciences ,Troposphere ,lcsh:Chemistry ,sulfuric-acid ,size distribution ,particle formation events ,continental boundary-layer ,boreal forest ,0105 earth and related environmental sciences ,Chemistry ,atmospheric nucleation ,lcsh:QC1-999 ,Aerosol ,number concentrations ,lcsh:QD1-999 ,13. Climate action ,pittsburgh air-quality ,mode particles ,Turbulence kinetic energy ,lcsh:Physics ,Dimensionless quantity - Abstract
Measurements of aerosol particle physical and chemical properties, gas phase concentrations and meteorological parameters were made along a transect in southern Indiana during the Nucleation In ForesTs (NIFTy) experiment conducted in May 2008. These measurements indicate nucleation was observed at all three measurement sites on almost half of all sampling days. The intensity of the nucleation events, as measured by the increase in ≥10 nm aerosol particle number concentrations of approximately 2×104 cm−3 over a layer of at least 300 m depth, is in good agreement with recent model results for the Midwestern USA derived using PMCAMx-UF. During the hour after termination of nucleation approximately half of the number concentration reduction is due to coagulation, while the remainder is due in equal parts to dry deposition and entrainment of relatively ultra-fine aerosol particle free troposphere air. Clear nucleation with continuous subsequent growth is only observed on days when the morning fractional cloud cover was less than 30%. It is associated with a clear transition from a strongly stratified atmosphere with low turbulence intensity and weak vertical velocities, to much a weaker vertical gradient of wind speed, increased turbulence intensity and stronger downwards vertical velocities, consistent with growth of the mixed layer and entrainment of air from the residual layer. Nucleation intensity is not very strongly determined by the prevailing condensational sink. However, there is a strong correlation between both a modified version of the Nucleation Parameter from Boy and Kulmala (2002) and ultrafine aerosol particle number concentrations, and mean morning H2SO4 concentrations and ultrafine aerosol particle number concentrations. Five A-class event days during NIFTy were characterized by values of the dimensionless nucleation parameter of Kuang et al. (2010) that are below 0.3, further indicating the applicability of their postulate that nucleation is favored by LΓ values below 0.7. Based on aerosol particle composition measurements it appears that aerosol particle formation and initial growth to approximately 30 nm diameter is dominated by ammonium and sulfate. Conservative estimates of the percent contribution of H2SO4 to aerosol particle growth (for sub-30 nm aerosol particles) on five A-class event days ranged from 23 to 85%.
- Published
- 2011
31. Ambient ultrafine particle levels at residential and reference sites in urban and rural Switzerland
- Author
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Harish C. Phuleria, Inmaculada Aguilera, Christian Schindler, Nino Künzli, Alex Ineichen, Ming-Yi Tsai, Martin Fierz, Reto Meier, Marloes Eeftens, Mark Davey, Martina S. Ragettli, and Nicole Probst-Hensch
- Subjects
Adult ,Male ,Nitrogen ,Air-Pollution ,Air pollution ,Rural Health ,medicine.disease_cause ,Exposure ,Air monitoring ,Human health ,Environmental health ,Air Pollution ,Ultrafine particle ,medicine ,Highway ,Environmental Chemistry ,Humans ,Number Concentrations ,Variability ,Air Pollutants ,Spatially resolved ,Environmental engineering ,Urban Health ,General Chemistry ,Models, Theoretical ,Spatiotemporal Variation ,13. Climate action ,Housing ,Environmental science ,Particulate Matter ,Seasons ,Diffusion Size Classifier ,Exposure data ,Switzerland ,Arithmetic mean ,Environmental Monitoring - Abstract
Although there is evidence that ultrafine particles (UFP) do affect human health there are currently no legal ambient standards. The main reasons are the absence of spatially resolved exposure data to investigate long-term health effects and the challenge of defining representative reference sites for monitoring given the high dependence of UFP on proximity to sources. The objectives of this study were to evaluate the spatial distribution of UFP in four areas of the Swiss Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA) and to investigate the representativeness of routine air monitoring stations for residential sites in these areas. Repeated UFP measurements during three seasons have been conducted at a total of 80 residential sites and four area specific reference sites over a median duration of 7 days. Arithmetic mean residential PNC scattered around the median of 10,800 particles/cm(3) (interquartile range [IQR] = 7800 particles/cm(3)). Spatial within area contrasts (90th/10th percentile ratios) were around two; increased contrasts were observed during weekday rush-hours. Temporal UFP patterns were comparable at reference and residential sites in all areas. Our data show that central monitoring sites can represent residential conditions when locations are well chosen with respect to the local sources--namely traffic. For epidemiological research, locally resolved spatial models are needed to estimate individuals' long-term exposures to UFP of outdoor origin at home, during commute and at work.
- Published
- 2015
32. Composition of 15–85 nm particles in marine air
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J. D. Whitehead, Colin D. O'Dowd, Ciaran Monahan, James N. Smith, Michael J. Lawler, and Gordon McFiggans
- Subjects
Atmospheric Science ,Ammonium sulfate ,Particle number ,Analytical chemistry ,nonmethane hydrocarbons ,Chloride ,ionization mass-spectrometry ,lcsh:Chemistry ,chemistry.chemical_compound ,medicine ,Organic chemistry ,14. Life underwater ,Sulfate ,Chemical composition ,Benzoic acid ,Chemical ionization ,Chemistry ,size distributions ,atmospheric particles ,boundary-layer ,lcsh:QC1-999 ,number concentrations ,lcsh:QD1-999 ,13. Climate action ,Particle ,chemical-composition ,water-uptake ,differential mobility analyzer ,secondary organic aerosol ,lcsh:Physics ,medicine.drug - Abstract
The chemical composition of 15–85 nm diameter particles was measured at Mace Head, Ireland, during May 2011 using the TDCIMS (thermal desorption chemical ionization mass spectrometer). Measurable levels of chloride, sodium, and sulfate were present in essentially all collected samples of these particles at this coastal Atlantic site. Acetaldehyde and benzoic acid were also frequently detected. Concomitant particle hygroscopicity observations usually showed a sea-salt mode and a lower hygroscopicity mode with growth factors near to that of ammonium sulfate. There were many periods lasting from hours to about 2 days during which the 10–60 nm particle number increased dramatically in polar oceanic air. These periods were correlated with the presence of benzoic acid in the particles and an increase in the number of lower hygroscopicity mode particles. Very small (< 10 nm) particles were also present, suggesting that new particle formation contributed to these nanoparticle enhancement events.
- Published
- 2014
33. Impact of gas-to-particle partitioning approaches on the simulated radiative effects of biogenic secondary organic aerosol
- Abstract
The oxidation of biogenic volatile organic compounds (BVOCs) gives a range of products, from semi-volatile to extremely low-volatility compounds. To treat the interaction of these secondary organic vapours with the particle phase, global aerosol microphysics models generally use either a thermodynamic partitioning approach (assuming instant equilibrium between semi-volatile oxidation products and the particle phase) or a kinetic approach (accounting for the size dependence of condensation). We show that model treatment of the partitioning of biogenic organic vapours into the particle phase, and consequent distribution of material across the size distribution, controls the magnitude of the first aerosol indirect effect (AIE) due to biogenic secondary organic aerosol (SOA). With a kinetic partitioning approach, SOA is distributed according to the existing condensation sink, enhancing the growth of the smallest particles, i.e. those in the nucleation mode. This process tends to increase cloud droplet number concentrations in the presence of biogenic SOA. By contrast, an approach that distributes SOA according to pre-existing organic mass restricts the growth of the smallest particles, limiting the number that are able to form cloud droplets. With an organically mediated new particle formation mechanism, applying a mass-based rather than a kinetic approach to partitioning reduces our calculated global mean AIE due to biogenic SOA by 24 %. Our results suggest that the mechanisms driving organic partitioning need to be fully understood in order to accurately describe the climatic effects of SOA.
- Published
- 2015
34. Variations in tropospheric submicron particle size distributions across the european continent 2008–2009
- Author
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Antoon Visschedijk, Ari Asmi, David C. S. Beddows, Gyula Kiss, Karine Sellegri, Roy M. Harrison, Manuel Dall'Osto, Angela Marinoni, Hans-Christen Hansson, Markus Fiebig, Colin D. O'Dowd, Urs Baltensperger, Nadezda Zikova, Niku Kivekäs, P. P. Aalto, Nikos Kalivitis, Markku Kulmala, Paolo Laj, Nikos Mihalopoulos, Nicolas Bukowiecki, J-P Putaud, Eija Asmi, Peter Tunved, Alfred Wiedensohler, S. G. Jennings, Ernest Weingartner, G. de Leeuw, Harald Flentje, Ivo Kalapov, Ludwig Ries, A. M. Fjaeraa, Wolfram Birmili, F. Meinhardt, Bas Henzing, Erik Swietlicki, H. A. C. Denier van der Gon, V. Zdimal, Vidmantas Ulevicius, and Heikki Lihavainen
- Subjects
Arctic haze ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,Particle number ,aerosol ,air ,Earth & Environment ,010501 environmental sciences ,Environment ,Atmospheric sciences ,growth-rates ,01 natural sciences ,lcsh:Chemistry ,Troposphere ,Zeppelinobservatoriet ,Urban Development ,size distribution ,Cluster (physics) ,Growth rate ,Built Environment ,Air mass ,0105 earth and related environmental sciences ,long-term ,Industrial Innovation ,zeppelin station ,Earth / Environmental ,atmospheric particles ,urban atmosphere ,boundary-layer ,CAS - Climate, Air and Sustainability ,particle size ,lcsh:QC1-999 ,Aerosol ,Europe ,spatiotemporal variability ,number concentrations ,lcsh:QD1-999 ,troposphere ,13. Climate action ,Sustainable Chemical Industry ,Environmental science ,ELSS - Earth, Life and Social Sciences ,EELS - Earth, Environmental and Life Sciences ,Longitude ,lcsh:Physics ,cluster analysis - Abstract
Beddows, D. C. S. ... et. al.-- 22 pages, 11 figures, 1 table, supplementary material related to this article is available online at http://www.atmos-chem-phys.net/14/4327/2014/acp-14-4327-2014-supplement.pdf, Clusteranalysis of particle number size distributions frombackground sites across Europeis presented. This generated a total of nine clusters of particle size distributions which could be further combined into two main groups, namely: a south-to-north category (four clusters) and a west-to-east category (five clusters). The first group was identified as most frequently being detected inside and around northern Germany and neighbouring countries, showing clear evidence of local afternoon nucleation and growth events that could be linked to movement of air masses from south to north arriving ultimately at the Arctic contributing to Arctic haze.The second group of particle size spectra proved to have narrower size distributions and collectively showed a dependence of modal diameter upon the longitude of the site (west to east) at which they were most frequently detected.These clusters indicated regional nucleation (at the coastal sites) growing to larger modes further inland. The apparent growth rate of the modal diameter was around 0.6-0.9 nm h-1. Four specific air mass back-trajectories were successively taken as case studies to examine in real time the evolution of aerosol size distributions across Europe. While aerosol growth processes can be observed as aerosol traverses Europe, the processes are often obscured by the addition of aerosol by emissions en route. This study revealed that some of the 24 stations exhibit more complex behaviour than others, especially when impacted by local sources or a variety of different air masses. Overall, the aerosol size distribution clustering analysis greatly simplifies the complex data set and allows a description of aerosol aging processes, which reflects the longer-term average development of particle number size distributions as air masses advect across Europe. © 2014 Author(s), The National Centre for Atmospheric Science is funded by the UK Natural Environment Research Council. This work was also supported by the European Union EUCAARI (Contract Ref. 036833) and EUSAAR (Contract Ref. 026140) research projects
- Published
- 2014
35. Formation and growth of nucleated particles into cloud condensation nuclei: model\u2013measurement comparison
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Westervelt, D.M.a, Pierce, J.R.b, Riipinen, I.ac, Trivitayanurak, W.d, Hamed, A.ef, Kulmala, M.g, Laaksonen, A.gh, Decesari, S.i, Adams, and P.J.a
- Subjects
ATMOSPHERIC AEROSOL NUCLEATION ,SULFURIC-ACID ,BOREAL FOREST ,INITIAL STEPS ,ASSIMILATED METEOROLOGY ,NUMBER CONCENTRATIONS ,AMBIENT MEASUREMENTS ,ULTRAFINE PARTICLES ,CCN CONCENTRATIONS ,SIZE DISTRIBUTION ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,Particle number ,Meteorology ,Chemistry ,Condensation ,Nucleation ,010501 environmental sciences ,01 natural sciences ,lcsh:QC1-999 ,Aerosol ,lcsh:Chemistry ,lcsh:QD1-999 ,13. Climate action ,Chemical physics ,Cloud condensation nuclei ,Particle ,Growth rate ,Ternary operation ,lcsh:Physics ,0105 earth and related environmental sciences - Abstract
Aerosol nucleation occurs frequently in the atmosphere and is an important source of particle number. Observations suggest that nucleated particles are capable of growing to sufficiently large sizes that they act as cloud condensation nuclei (CCN), but some global models have reported that CCN concentrations are only modestly sensitive to large changes in nucleation rates. Here we present a novel approach for using long-term size distribution observations to evaluate a global aerosol model's ability to predict formation rates of CCN from nucleation and growth events. We derive from observations at five locations nucleation-relevant metrics such as nucleation rate of particles at diameter of 3 nm (J3), diameter growth rate (GR), particle survival probability (SP), condensation and coagulation sinks, and CCN formation rate (J100). These quantities are also derived for a global microphysical model, GEOS-Chem-TOMAS, and compared to the observations on a daily basis. Using GEOS-Chem-TOMAS, we simulate nucleation events predicted by ternary (with a 10−5 tuning factor) or activation nucleation over one year and find that the model slightly understates the observed annual-average CCN formation mostly due to bias in the nucleation rate predictions, but by no more than 50% in the ternary simulations. At the two locations expected to be most impacted by large-scale regional nucleation, Hyytiälä and San Pietro Capofiume, predicted annual-average CCN formation rates are within 34 and 2% of the observations, respectively. Model-predicted annual-average growth rates are within 25% across all sites but also show a slight tendency to underestimate the observations, at least in the ternary nucleation simulations. On days that the growing nucleation mode reaches 100 nm, median single-day survival probabilities to 100 nm for the model and measurements range from less than 1–6% across the five locations we considered; however, this does not include particles that may eventually grow to 100 nm after the first day. This detailed exploration of new particle formation and growth dynamics adds support to the use of global models as tools for assessing the contribution of microphysical processes such as nucleation to the total number and CCN budget.
- Published
- 2013
36. The regional aerosol-climate model REMO-HAM
- Author
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Gerald Spindler, Claas Teichmann, Markku Kulmala, Ute Karstens, Stephanie Fiedler, Robert Gehrig, Daniela Jacob, Johann Feichter, Urs Baltensperger, Joni-Pekka Pietikäinen, Wolfram Birmili, Colin D. O'Dowd, Jan Kazil, Ralf Podzun, Declan O'Donnell, Ernest Weingartner, Ari Laaksonen, Sascha Pfeifer, and Harri Kokkola
- Subjects
010504 meteorology & atmospheric sciences ,Meteorology ,Nucleation mode ,0207 environmental engineering ,Nucleation ,02 engineering and technology ,general-circulation model ,cloud microphysics ,010501 environmental sciences ,Atmospheric sciences ,01 natural sciences ,Gas phase ,back trajectories analysis ,Precipitation ,020701 environmental engineering ,dry deposition parameterization ,stratospheric conditions ,Physics::Atmospheric and Oceanic Physics ,0105 earth and related environmental sciences ,particle formation ,lcsh:QE1-996.5 ,boundary-layer ,Aerosol ,lcsh:Geology ,nucleation events ,Boundary layer ,small implicit diffusion ,number concentrations ,13. Climate action ,Environmental science ,Climate model - Abstract
REMO-HAM is a new regional aerosol-climate model. It is based on the REMO regional climate model and includes most of the major aerosol processes. The structure for aerosol is similar to the global aerosol-climate model ECHAM5-HAM, for example the aerosol module HAM is coupled with a two-moment stratiform cloud scheme. On the other hand, REMO-HAM does not include an online coupled aerosol-radiation nor a secondary organic aerosol module. In this work, we evaluate the model and compare the results against ECHAM5-HAM and measurements. Four different measurement sites were chosen for the comparison of total number concentrations, size distributions and gas phase sulfur dioxide concentrations: Hyytiälä in Finland, Melpitz in Germany, Mace Head in Ireland and Jungfraujoch in Switzerland. REMO-HAM is run with two different resolutions: 50 × 50 km2 and 10 × 10 km2. Based on our simulations, REMO-HAM is in reasonable agreement with the measured values. The differences in the total number concentrations between REMO-HAM and ECHAM5-HAM can be mainly explained by the difference in the nucleation mode. Since we did not use activation nor kinetic nucleation for the boundary layer, the total number concentrations are somewhat underestimated. From the meteorological point of view, REMO-HAM represents the precipitation fields and 2 m temperature profile very well compared to measurement. Overall, we show that REMO-HAM is a functional aerosol-climate model, which will be used in further studies.
- Published
- 2012
37. Observation of regional new particle formation in the urban atmosphere
- Abstract
Long-term measurements of fine particle number-size distributions were carried out over 9.5 yr (May 1997-December 2006), in the urban background atmosphere of Helsinki. The total number of days was 3528 with about 91.9% valid data. A new particle formation event (NPF) is defined if a distinct nucleation mode of aerosol particles is observed below 25 nm for several hours, and it shows a growth pattern. We observed 185 NPF events, 111 d were clear non-events and most of the days (around 83.5%) were undefined. The observed events were regional because they were observed at Hyytiala (250 km north of Helsinki). The events occurred most frequently during spring and autumn. The observed formation rate was maximum during the spring and summer (monthly median 2.87 cm(-3) s(-1)) and the modal growth rate was maximum during late summer and Autumn (monthly median 6.55 mm h(-1)). The events were observed around noon, and the growth pattern often continued on the following day. The observation of weak NPF events was hindered due to pre-existing particles from both local sources. It is clear that regional NPF events have a clear influence oil the dynamic behaviour of aerosol particles in the urban atmosphere., authorCount :9
- Published
- 2008
- Full Text
- View/download PDF
38. Trends in atmospheric new-particle formation: 16 years of observations in a boreal-forest environment
- Author
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Nieminen, Tuomo, Asmi, Ari, Dal Maso, Miikka, Aalto, Pasi P., Keronen, Petri, Petaja, Tuukka, Markku Kulmala, Kerminen, Veli-Matti, Helsinki Institute of Physics, Department of Physics, and Aerosol-Cloud-Climate -Interactions (ACCI)
- Subjects
GROWTH-RATES ,SULFURIC-ACID CONCENTRATION ,NUMBER CONCENTRATIONS ,education ,SIZE DISTRIBUTION MEASUREMENTS ,TRAJECTORY ANALYSIS ,AEROSOL DECADAL TRENDS ,SMEAR II STATION ,NUCLEATION MODE PARTICLES ,114 Physical sciences ,CLOUD CONDENSATION NUCLEI ,TERNARY NUCLEATION
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