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  1. Artikel ; Online: Contribution of airborne dust particles to HONO sources

    N. A. Saliba / S. G. Moussa / G. El Tayyar

    Atmospheric Chemistry and Physics Discussions, Vol 14, Iss 4, Pp 4827-

    2014  Band 4839

    Abstract: ... aerosol surfaces. In particular, dust events which are loaded with mineral oxide aerosols have been ... a synergistic mechanism of adsorption and reaction between NO 2 and SO 2 on dust particles to produce HONO and ... of reactions related to this process, samples during dusty and non-dusty days were collected between October ...

    Abstract HONO is a major precursor for OH radicals in early mornings. Its formation has been mainly attributed to the heterogeneous hydrolysis of NO 2 on surfaces such as soot, glass, mineral oxides and aerosol surfaces. In particular, dust events which are loaded with mineral oxide aerosols have been associated with higher HONO concentrations in the gas phase. In order to understand the mechanism of reactions related to this process, samples during dusty and non-dusty days were collected between October 2009 and April 2011. Based on HYSPLIT backward trajectories, data were divided between wind trajectories originating from Arabian or African deserts. In this study an increase of HONO levels was observed during dusty days. The increase in the acidic gas concentrations was accompanied by an increase in the PM nitrate and sulfate ion concentrations. During high relative humidity (African dusty days), it is proposed that the mechanism of NO 2 hydrolysis predominates whereas during Arabian dusty days, where the air is relatively dry, a synergistic mechanism of adsorption and reaction between NO 2 and SO 2 on dust particles to produce HONO and sulfate in the particle phase is suggested. This study implies that the NO x reactivity on mineral oxide surfaces leads to a higher mixing level of OH. An increase in the sulfate forming capacity could account for the underestimation of sulfates in aerosols when the reactive uptake of SO 2 alone is considered.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2014-02-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  2. Artikel ; Online: Composition and sources of particulate matter in an industrialised Alpine valley

    N. Perron / J. Sandradewi / M. R. Alfarra / P. Lienemann / R. Gehrig / A. Kasper-Giebl / V. A. Lanz / S. Szidat / M. Ruff / S. Fahrni / L. Wacker / U. Baltensperger / A. S. H. Prévôt

    Atmospheric Chemistry and Physics Discussions, Vol 10, Iss 4, Pp 9391-

    2010  Band 9430

    Abstract: ... of BC highlighted the prevalence of fossil over wood-burning sources. Three types of PM 1 organics ... carbonaceous fractions, mineral dust components and several trace elements showed a significant decrease ...

    Abstract A three-week long field campaign was carried out under autumnal meteorological conditions at four valley floor sites in the industrialised Swiss Rhone Valley. For one week of stable meteorological conditions, particulate matter with an aerodynamic diameter below 10 μm (PM 10 ) was analysed from daily filters using ion chromatography, X-ray fluorescence, anhydrosugars and radiocarbon analysis of the organic and elemental matter (OM and EM, respectively). Furthermore, PM 1 composition along the whole campaign was monitored in Massongex (a site near industries) by a seven-wavelength aethalometer and a quadrupole aerosol mass spectrometer (Q-AMS). At all sites, PM 10 secondary inorganics and non-fossil EM and OM exhibited relatively stable concentrations over the selected days. On the contrary, PM 10 fossil carbonaceous fractions, mineral dust components and several trace elements showed a significant decrease on Sunday, compared to the analysed working days. Their concentrations were also highly correlated. This evidenced the role of exhaust and resuspension emissions by heavy-duty vehicle traffic to the PM 10 concentrations along the valley. In Massongex, organic matter and black carbon (BC) were the main contributors to PM 1 over the campaign (accounting for 45% and 18% of PM 1 , respectively). An optical discrimination of BC highlighted the prevalence of fossil over wood-burning sources. Three types of PM 1 organics could be identified by factor analysis: primary wood-burning organic aerosol (P-WBOA) dominated the PM 1 carbonaceous fraction, followed by oxygenated organics (OOA) mostly representing secondary organics, and by traffic or possibly industry-related hydrocarbon-like organics (HOA) as the smallest carbonaceous contribution. Furthermore, unusually high contributions of fine chloride were detected at all sites. They were attributed to ammonium chloride (NH 4 Cl) in Massongex and represented the only significant component exclusively attributable to industrial emissions.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 290
    Sprache Englisch
    Erscheinungsdatum 2010-04-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
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  3. Artikel ; Online: Sources, trends and regional impacts of fine particulate matter in southern Mississippi Valley

    M.-C. Chalbot / B. McElroy / I. G. Kavouras

    Atmospheric Chemistry and Physics Discussions, Vol 13, Iss 1, Pp 827-

    significance of emissions from sources in the Gulf of Mexico coast

    2013  Band 862

    Abstract: ... biomass burning, diesel particles, aged/contaminated sea salt and mineral/road dust, accounting for more ... The sources of fine particles over a 10 yr period at Little Rock, Arkansas, an urban area ... and its sources and their associations with the pathways of air mass backward trajectories were ...

    Abstract The sources of fine particles over a 10 yr period at Little Rock, Arkansas, an urban area in southern Mississippi Valley, were identified by positive matrix factorization. The annual trends of PM 2.5 and its sources and their associations with the pathways of air mass backward trajectories were examined. Seven sources were apportioned, namely, primary traffic particles, secondary nitrate and sulphate, biomass burning, diesel particles, aged/contaminated sea salt and mineral/road dust, accounting for more than 90% of measured PM 2.5 mass. The declining trend of PM 2.5 mass (0.4 μg m −3 yr −1 ) was related to lower levels of SO 4 2− (0.2 μg m −3 yr −1 ) due to SO 2 reductions from point and mobile sources. The slower decline for NO 3 − particles (0.1 μg m −3 yr −1 ) was attributed to the spatial variability of NH 3 in Midwest. The annual variation of biomass burning particles was associated with wildland fires in southeast and northwest US that are sensitive to climate changes. The four regions within 500 km from the receptor site, the Gulf Coast and southeast US accounted cumulatively for more than 65% of PM 2.5 mass, nitrate, sulphate and biomass burning aerosol. Overall, more than 50% of PM 2.5 and its sources originated from sources outside the state. Sources within the Gulf Coast and western Gulf of Mexico include 65% of the busiest ports in the US, intense marine traffic within 400 km of the coast burning rich in S diesel, and a large number of offshore oil and natural gas platforms and many refineries along the coast. This approach allowed for quantitatively assessing the impacts of transport from regions representing diverse mixtures of sources and weather conditions for different types of particles. The findings of this effort demonstrated the influences of emission controls on SO 2 and NO x on PM 2.5 mass, the potential effect of events (i.e. fires) sensitive to climate change phenomena on air pollution and the potential of offshore activities and shipping emissions to influence air quality in urban areas located more than 1000 km away from the sources.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2013-01-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel ; Online: Identifying the sources driving observed PM 2.5 variability over Halifax, Nova Scotia, during BORTAS-B

    A. J. Wheeler / Z. Li / J. E. Franklin / W. R. Leaitch / G. H. King / S. Beauchamp / J. T. Hopper / T. J. Duck / L. Chisholm / J. S. Kuchta / D. Waugh / J. R. Pierce / M. D. Gibson / G. A. Gagnon / P. I. Palmer

    Atmospheric Chemistry and Physics Discussions, Vol 13, Iss 2, Pp 4491-

    2013  Band 4533

    Abstract: ... Vehicles 0.49 μg m −3 (13.2%), Fugitive Dust 0.23 μg m −3 (6.3%), Ship Emissions 0.13 μg m −3 (3.4%) and ... into the local and upwind sources impacting surface PM 2.5 in Halifax during the BORTAS-B mission. ... The source attribution of observed variability of total PM 2.5 concentrations over Halifax ...

    Abstract The source attribution of observed variability of total PM 2.5 concentrations over Halifax, Nova Scotia was investigated between 11 July–26 August 2011 using measurements of PM 2.5 mass and PM 2.5 chemical composition (black carbon, organic matter, anions, cations and 33 elements). This was part of the BORTAS-B (quantifying the impact of BOReal forest fires on Tropospheric oxidants using aircraft and satellites) experiment, which investigated the atmospheric chemistry and transport of seasonal boreal wild fire emissions over eastern Canada in 2011. The US EPA Positive Matrix Factorization (PMF) receptor model was used to determine the average mass (percentage) source contribution over the 45 days, which was estimated to be: Long-Range Transport (LRT) Pollution 1.75 μg m −3 (47%), LRT Pollution Marine Mixture 1.0 μg m −3 (27.9%), Vehicles 0.49 μg m −3 (13.2%), Fugitive Dust 0.23 μg m −3 (6.3%), Ship Emissions 0.13 μg m −3 (3.4%) and Refinery 0.081 μg m −3 (2.2%). The PMF model describes 87% of the observed variability in total PM 2.5 mass (bias = 0.17 and RSME = 1.5 μg m −3 ). The factor identifications are based on chemical markers, and they are supported by air mass back trajectory analysis and local wind direction. Biomass burning plumes, found by other surface and aircraft measurements, were not significant enough to be identified in this analysis. This paper presents the results of the PMF receptor modelling, providing valuable insight into the local and upwind sources impacting surface PM 2.5 in Halifax during the BORTAS-B mission.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2013-02-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  5. Artikel ; Online: Ancient versus modern mineral dust transported to high-altitude alpine glaciers evidences saharan sources and atmospheric circulation changes

    F. Thevenon / M. Chiaradia / T. Adatte / C. Hueglin / J. Poté

    Atmospheric Chemistry and Physics Discussions, Vol 11, Iss 1, Pp 859-

    2011  Band 884

    Abstract: ... Backward trajectories analysis of modern analogs furthermore confirms that major dust sources are situated ... deposition, suggesting intercontinental transport of background dust rather than activation of a secondary source ... Gnifetti glacier (45°55' N, 7°52' E, 4455 m a.s.l.) over the last millennium. Insoluble dust has been ...

    Abstract Mineral dust aerosols collected during the years 2008/09 at the high-altitude research station Jungfraujoch (46°33' N, 7°59' E; 3580 m a.s.l.) were compared to windblown mineral dust deposited at the Colle Gnifetti glacier (45°55' N, 7°52' E, 4455 m a.s.l.) over the last millennium. Insoluble dust has been characterized in terms of mineralogy, Sr and Nd isotopic ratios, and trace element composition. Results demonstrate that the Saharan origin of the airborne dust did not change significantly throughout the past. Backward trajectories analysis of modern analogs furthermore confirms that major dust sources are situated in the north-central to north-western part of the Saharan desert. By contrast, less radiogenic Sr isotopic compositions are associated with lower abundances of crustal elements during low rates of dust deposition, suggesting intercontinental transport of background dust rather than activation of a secondary source. Saharan dust mobilization and meridional advection of air masses were relatively reduced during the second part of the Little Ice Age (ca. 1690–1870), except within the greatest Saharan dust event deposited around 1780–1790. Higher dust deposition with larger mean grain size and Saharan fingerprint began ca. 20 years after the industrial revolution of 1850, suggesting that increased mineral dust transport over the Alps during the last century was primarily due to drier winters in North Africa and stronger spring/summer North Atlantic southwesterlies, rather than to direct anthropogenic sources. Meanwhile, increasing carbonaceous particle emissions from fossil fuels combustion combined to higher lead enrichment factor during the last century, point to concomitant anthropogenic sources of particulate pollutants reaching high-altitude European glaciers.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 520
    Sprache Englisch
    Erscheinungsdatum 2011-01-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  6. Artikel ; Online: Airborne measurements of aerosol optical properties related to early spring transport of mid-latitude sources into the Arctic

    R. Adam de Villiers / G. Ancellet / J. Pelon / B. Quennehen / A. Scharwzenboeck / J. F. Gayet / K. S. Law

    Atmospheric Chemistry and Physics Discussions, Vol 9, Iss 6, Pp 27791-

    2009  Band 27836

    Abstract: ... Asia emissions (i.e. an expected mixture of Asian pollution and dust), while low depolarisation ... depolarization at 355 nm aims at distinguishing the role of the different aerosol sources (Siberian wild fires ... the role of the different aerosol sources even after a transport time larger than 4 days. Above Asia ...

    Abstract Airborne lidar and in-situ measurements of the aerosol properties were conducted between Svalbard Island and Scandinavia in April 2008. Evidence of aerosol transport from Europe and Asia is given. The analysis of the aerosol optical properties based on a multiwavelength lidar (355, 532, 1064 nm) including depolarization at 355 nm aims at distinguishing the role of the different aerosol sources (Siberian wild fires, Eastern Asia and European anthropogenic emissions). Combining, first aircraft measurements, second FLEXPART simulations with a calculation of the PBL air fraction originating from the three different mid-latitude source regions, and third level-2 CALIPSO data products (i.e. backscatter coefficient, depolarisation and color ratio in aerosol layers) along the transport pathways, appears a valuable approach to identify the role of the different aerosol sources even after a transport time larger than 4 days. Above Asia, CALIPSO data indicate more depolarisation (up to 15%) and largest color ratio (>0.5) for the northeastern Asia emissions (i.e. an expected mixture of Asian pollution and dust), while low depolarisation together with smaller and quasi constant color ratio (≈0.3) are observed for the Siberian biomass burning emissions. A similar difference is visible between two layers observed by the aircraft above Scandinavia. The analysis of the time evolution of the aerosol optical properties revealed by CALIPSO between Asia and Scandinavia shows a gradual decrease of the aerosol backscatter, depolarisation ratio and color ratio which suggests the removal of the largest particles in the accumulation mode. A similar study conducted for a European plume has shown aerosol optical properties intermediate between the two Asian sources with color ratio never exceeding 0.4 and moderate depolarisation ratio being always less than 8%, i.e. less aerosol from the accumulation mode.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 551
    Sprache Englisch
    Erscheinungsdatum 2009-12-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  7. Artikel ; Online: Ancient versus modern mineral dust transported to high-altitude Alpine glaciers evidences Saharan sources and atmospheric circulation changes

    F. Thevenon / M. Chiaradia / T. Adatte / C. Hueglin / J. Poté

    Atmospheric Chemistry and Physics Discussions, Vol 10, Iss 8, Pp 20167-

    2010  Band 20191

    Abstract: ... Backward trajectories analysis of modern analogs furthermore confirms that major dust sources are situated ... deposition, suggesting intercontinental transport of background dust rather than activation of a secondary source ... Gnifetti glacier (45°55´ N, 7°52´ E; 4455 m a.s.l.) over the last millennium. Insoluble dust has been ...

    Abstract Mineral dust aerosols collected during the years 2008/2009 at the high-altitude research station Jungfraujoch (46°33´, 7°59´; 3580 m a.s.l.) were compared to windblown mineral dust deposited at the Colle Gnifetti glacier (45°55´ N, 7°52´ E; 4455 m a.s.l.) over the last millennium. Insoluble dust has been characterized in terms of mineralogy, Sr and Nd isotopic ratios, and trace element composition. Results demonstrate that the Saharan origin of the airborne dust did not change significantly throughout the past. Backward trajectories analysis of modern analogs furthermore confirms that major dust sources are situated in the north-central to north-western part of the Saharan desert. By contrast, less radiogenic Sr isotopic compositions are associated with lower abundances of crustal elements during low rates of dust deposition, suggesting intercontinental transport of background dust rather than activation of a secondary source. Saharan dust mobilization and meridional advection of air masses were relatively reduced during the second part of the Little Ice Age (ca. 1690–1870), except within the greatest Saharan dust event deposited around 1780–1790. Higher dust deposition with larger mean grain size and Saharan fingerprint began ca. 20 years after the industrial revolution of 1850, suggesting that increased mineral dust transport over the Alps during the last century was primarily due to drier winters in North Africa and stronger spring/summer North Atlantic southwesterlies, rather than to direct anthropogenic sources. Meanwhile, increasing carbonaceous particle emissions from fossil fuels combustion combined to higher lead enrichment factor during the last century, point to concomitant anthropogenic sources of particulate pollutants reaching high-altitude European glaciers.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 520
    Sprache Englisch
    Erscheinungsdatum 2010-08-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  8. Artikel ; Online: Source, transport and impacts of a heavy dust event in the Yangtze River Delta, China in 2011

    X. Fu / S. X. Wang / Z. Cheng / J. Xing / B. Zhao / J. D. Wang / J. M. Hao

    Atmospheric Chemistry and Physics Discussions, Vol 13, Iss 8, Pp 21507-

    2013  Band 21540

    Abstract: ... as air quality and human health when resuspending in the atmosphere. Due to the impacts of mineral dust ... During 1 to 6 May 2011, a dust event was observed in the Yangtze River Delta region (YRD ... the Community Multi-scale Air Quality modeling system (CMAQ5.0) coupled with an in-line windblown dust model was ...

    Abstract During 1 to 6 May 2011, a dust event was observed in the Yangtze River Delta region (YRD). The highest PM 10 concentration reached over 1000 μg m −3 and the visibility was below 3 km. In this study, the Community Multi-scale Air Quality modeling system (CMAQ5.0) coupled with an in-line windblown dust model was used to simulate the formation, spatial and temporal characteristics of this dust event, and analyze its impacts on deposition and photochemistry. The threshold friction velocity for loose smooth surface in the dust model was revised based on Chinese data to improve the model performance. The comparison between predictions and observations indicates the revised model can reproduce the transport and pollution of the event. The simulation results show that the dust event was affected by formation and transport of Mongolian cyclone and cold air. Totally about 695 kt dust particles (PM 10 ) were emitted in Xinjiang Province and Mongolia during 28 to 30 April, the dust band swept northern, eastern China and then arrived in the YRD region on 1 May 2011. The transported dust particles increased the mean surface layer concentrations of PM 10 in the YRD region by 372% during 1 to 6 May and the impacts weakened from north to south due to the removal of dust particles along the path. Accompanied by high PM concentration, the dry deposition, wet deposition and total deposition of PM 10 in the YRD reached 184.7 kt, 172.6 kt and 357.32 kt, respectively. These deposited particles are very harmful because of their impacts on urban environment as well as air quality and human health when resuspending in the atmosphere. Due to the impacts of mineral dust on atmospheric photolysis, the concentrations of O 3 and OH were reduced by 1.5% and 3.1% in the whole China, and by 9.4% and 12.1% in the YRD region, respectively. The work of this manuscript is meaningful for understanding the dust emissions in China as well as for the application of CMAQ in Asia. It is also helpful to understand the formation mechanism and impacts of dust pollution in the YRD.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2013-08-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  9. Artikel ; Online: Chemical characterization and source apportionment of PM 2.5 in Beijing

    R. Zhang / J. Jing / J. Tao / S.-C. Hsu / G. Wang / J. Cao / C. S. L. Lee / L. Zhu / Z. Chen / Y. Zhao

    Atmospheric Chemistry and Physics Discussions, Vol 13, Iss 4, Pp 9953-

    seasonal perspective

    2013  Band 10007

    Abstract: ... of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning ... with PM 2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol ... for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely ...

    Abstract In this study, 121 daily PM 2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm) samples were collected from an urban site in Beijing in four months between April 2009 and January 2010 representing the four seasons. The samples were determined for various compositions, including elements, ions, and organic/elemental carbon. Various approaches, such as chemical mass balance, positive matrix factorization (PMF), trajectory clustering, and potential source contribution function (PSCF), were employed for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely source. Our results have shown distinctive seasonalities for various aerosol speciations associated with PM 2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol components, inorganic and organic species may behave in different manners. The former preferentially forms in the hot and humid summer via photochemical reactions, although their precursor gases, such as SO 2 and NO x , are emitted much more in winter. The latter seems to favorably form in the cold and dry winter. Synoptic meteorological and climate conditions can overwhelm the emission pattern in the formation of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning, traffic and waste incineration emission, industrial pollution, and secondary inorganic aerosol. Each of these sources has an annual mean contribution of 16, 14, 13, 3, 28, and 26%, respectively, to PM 2.5 . However, the relative contributions of these identified sources significantly vary with changing seasons. The results of trajectory clustering and the PSCF method demonstrated that regional sources could be crucial contributors to PM pollution in Beijing. In conclusion, we have unraveled some complex aspects of the pollution sources and formation processes of PM 2.5 in Beijing. To our knowledge, this study is the first systematical study that comprehensively explores the chemical characterizations and source apportionments of PM 2.5 aerosol speciation in Beijing by applying multiple approaches based on a completely seasonal perspective.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2013-04-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  10. Artikel ; Online: Source apportionment of ambient fine particle from combined size distribution and chemical composition data during summertime in Beijing

    Z. R. Liu / Y. S. Wang / Q. Liu / B. Hu / Y. Sun

    Atmospheric Chemistry and Physics Discussions, Vol 13, Iss 1, Pp 1367-

    2013  Band 1397

    Abstract: ... nitrate, secondary sulfate, coal-fired power plant and road dust. Nearly two-thirds ... of particle number concentrations were attributed to cooking (22.8%) and motor vehicle (37.5%), whereas road dust ... coal-fired power plant and regional sources contributed 69.0% to particle volume concentrations. Local and remote sources ...

    Abstract Continuous particle number concentration and chemical composition data were collected over one month during summertime in Beijing to investigate the source apportionment of ambient fine particles. Particle size distributions from 15 nm to 2.5 μm in diameter and composition data, such as organic matter, sulfate, nitrate, ammonium, chlorine, and gaseous pollutants, were analyzed using positive matrix factorisation (PMF) which indentified eight factors: cooking, solid mode exhaust, nucleation mode exhaust, accumulation mode, secondary nitrate, secondary sulfate, coal-fired power plant and road dust. Nearly two-thirds of particle number concentrations were attributed to cooking (22.8%) and motor vehicle (37.5%), whereas road dust, coal-fired power plant and regional sources contributed 69.0% to particle volume concentrations. Local and remote sources were distinguished using size distributions associated with each factor. Local sources were generally characterised by unimodal or bimodal number distributions, consisting mostly of particles less 0.1 μm in diameter, and regional sources were defined by mostly accumulation mode particles. Nearly one third of secondary nitrate and secondary sulfate was transported from the surrounding areas of Beijing during study period. Overall the introduction of combination of particle number concentration and chemical composition in PMF model is successful at separating the components and quantifying relative contributions to the particle number and volume population in a complex urban atmosphere.
    Schlagwörter Environmental sciences ; GE1-350 ; Geography. Anthropology. Recreation ; G ; DOAJ:Environmental Sciences ; DOAJ:Earth and Environmental Sciences ; Geophysics. Cosmic physics ; QC801-809
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2013-01-01T00:00:00Z
    Verlag Copernicus Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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