Special Issue "Emissions, Transport and Fate of Pollutants in the Atmosphere"

A special issue of Atmosphere (ISSN 2073-4433). This special issue belongs to the section "Air Quality".

Deadline for manuscript submissions: closed (15 May 2020).

Special Issue Editor

Dr. Hosein Foroutan
Website
Guest Editor
Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, USA
Interests: atmospheric transport; multiscale atmospheric modeling; turbulence and turbulent flows; planetary boundary layer meteorology; air quality modeling; air pollution; chemical transport models; aerosols emissions and transport; air-surface exchange; atmospheric dust

Special Issue Information

Dear Colleagues,

Air pollutants (including chemicals, pathogens, allergens, and toxics) go through many dynamical, physical, and chemical processes from emissions to deposition. Aerosols and gasses are released from various sources to the atmosphere, where they interact with the planetary boundary layer, radiation, and clouds. The transport and dispersion of pollutants may occur at various spatial and temporal scales before they are deposited back on land or water. There are still many scientific questions concerning multiscale and multiphysics phenomena that govern the emissions, transport, and fate of pollutants in the atmosphere.

This Special Issue is devoted to research that aims to improve our understanding of physical mechanisms controlling emissions, transport, and deposition of airborne pollutants, chemicals, pathogens, allergens, or toxics. We are especially interested in original research articles addressing the multiscale and multiphysics nature of these mechanisms. All theoretical, modeling, and observational studies are welcome. Some topics of interest include, but are not limited to:

  • Air-surface exchange of pollutants
  • Emissions due to atmosphere and land/water interactions
  • Pollutants pathways in the atmosphere
  • Long-range transport
  • Wet/dry deposition processes

Dr. Hosein Foroutan
Guest Editor

Manuscript Submission Information

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Keywords

  • Air-land and air-sea interactions
  • Pollutant and pathogen emissions
  • Turbulence and dispersion
  • Long-range transport
  • Multiscale air quality
  • Wet/dry deposition

Published Papers (14 papers)

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Research

Open AccessArticle
Investigation of Aerosol Climatology and Long-Range Transport of Aerosols over Pokhara, Nepal
Atmosphere 2020, 11(8), 874; https://doi.org/10.3390/atmos11080874 - 17 Aug 2020
Cited by 1 | Viewed by 1284
Abstract
This study presents the spectral monthly and seasonal variation of aerosol optical depth (τAOD), single scattering albedo (SSA), and aerosol absorption optical depth (AAOD) between 2010 and 2018 obtained from the Aerosol Robotic Network (AERONET) over Pokhara, Nepal. The analysis of [...] Read more.
This study presents the spectral monthly and seasonal variation of aerosol optical depth (τAOD), single scattering albedo (SSA), and aerosol absorption optical depth (AAOD) between 2010 and 2018 obtained from the Aerosol Robotic Network (AERONET) over Pokhara, Nepal. The analysis of these column-integrated aerosol optical data suggests significant monthly and seasonal variability of aerosol physical and optical properties. The pre-monsoon season (March to May) has the highest observed τAOD(0.75 ± 0.15), followed by winter (December to February, 0.47 ± 0.12), post-monsoon (October and November, 0.39 ± 0.08), and monsoon seasons (June to September, 0.27 ± 0.13), indicating seasonal aerosol loading over Pokhara. The variability of Ångström parameters, α, and β, were computed from the linear fit line in the logarithmic scale of spectral τAOD, and used to analyze the aerosol physical characteristics such as particle size and aerosol loading. The curvature of spectral τAOD, α’, computed from the second-order polynomial fit, reveals the domination by fine mode aerosol particles in the post-monsoon and winter seasons, with coarse mode dominating in monsoon, and both modes contributing in the pre-monsoon. Analysis of air mass back trajectories and observation of fire spots along with aerosol optical data and aerosol size spectra suggest the presence of mixed types of transboundary aerosols, such as biomass, urban-industrial, and dust aerosols in the atmospheric column over Pokhara. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Emission of Methyl Ethyl Ketone and 2-Butanol Converted from Methyl Vinyl Ketone in Plant Leaves
Atmosphere 2020, 11(8), 793; https://doi.org/10.3390/atmos11080793 - 27 Jul 2020
Cited by 1 | Viewed by 642
Abstract
Methacrolein (MACR) and methyl vinyl ketone (MVK) are key intermediate compounds in isoprene-initiated reactions, and they cause the formation of secondary organic aerosols and photochemical ozone. The importance of higher plants as a sink of these compounds and as a source of volatiles [...] Read more.
Methacrolein (MACR) and methyl vinyl ketone (MVK) are key intermediate compounds in isoprene-initiated reactions, and they cause the formation of secondary organic aerosols and photochemical ozone. The importance of higher plants as a sink of these compounds and as a source of volatiles converted from these compounds was addressed in the present study. We exposed four non-isoprene-emitting plant species to MACR and MVK at concentrations of several to several hundred ppb, measured their uptake rates, and analyzed the volatiles converted from MACR and MVK by these plants. We used a flow-through chamber method to determine the exchange rates. Both MACR and MVK were absorbed by all plants via stomata. Two metabolites, methyl ethyl ketone (MEK) and 2-butanol, were detected when MVK was fumigated. The conversion ratio was 26–39% for MEK and 33–44% for all volatiles. Combined with the results of two previous relevant reports, our results suggest that MEK conversion from MVK normally occurs in a wide range of plant species, but the conversion ratio may depend on plant type, i.e., if plant species are isoprene-emitting or non-emitting, as well as on the fumigation concentrations. This finding also emphasizes the importance of bilateral exchange measurements of these compounds at lower concentrations close to ambient levels. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Capturing the Variability in Instantaneous Vehicle Emissions Based on Field Test Data
Atmosphere 2020, 11(7), 765; https://doi.org/10.3390/atmos11070765 - 20 Jul 2020
Viewed by 548
Abstract
Emission models are important tools for traffic emission and air quality estimates. Existing instantaneous emission models employ the steady-state “engine emissions map” to estimate emissions for individual vehicles. However, vehicle emissions vary significantly, even under the same driving conditions. Variability in the emissions [...] Read more.
Emission models are important tools for traffic emission and air quality estimates. Existing instantaneous emission models employ the steady-state “engine emissions map” to estimate emissions for individual vehicles. However, vehicle emissions vary significantly, even under the same driving conditions. Variability in the emissions at a specific driving condition depends on various influencing factors. It is important to gain insight into the effects of these factors, to enable detailed modeling of individual vehicle emissions. This study employs a portable emissions measurement system (PEMS), to collect vehicle emissions including the corresponding parameters of engine condition, vehicle activity, catalyst temperature, geography, and meteorology, to analyze the variability in emission rates as a function of those factors, across different vehicle specific power (VSP) categories. We observe that carbon dioxide, carbon monoxide, nitrogen oxides, and particle number emissions are strongly correlated with engine parameters (engine speed, torque, load, and air-fuel ratio) and vehicle activity parameters (vehicle speed and acceleration). In the same VSP bin, emissions per second on highways and ramps are higher than those on arterial roads, and the emissions when the vehicle is traveling downhill tend to be higher than the emissions during uphill traveling, because of higher observed speeds and accelerations. Morning emissions are higher than afternoon emissions, due to lower temperatures. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Assessment of Gaseous and Particulate Emissions of a Euro 6d-Temp Diesel Vehicle Driven >1300 km Including Six Diesel Particulate Filter Regenerations
Atmosphere 2020, 11(6), 645; https://doi.org/10.3390/atmos11060645 - 17 Jun 2020
Cited by 4 | Viewed by 945
Abstract
Diesel-fueled vehicles have classically had high particulate and NOx emissions. The introduction of Diesel Particulate Filters (DPFs) and Selective Catalytic Reduction for NOx (SCR) systems have decreased the Particle Number (PN) and NOx emissions, respectively, to very low levels. However, [...] Read more.
Diesel-fueled vehicles have classically had high particulate and NOx emissions. The introduction of Diesel Particulate Filters (DPFs) and Selective Catalytic Reduction for NOx (SCR) systems have decreased the Particle Number (PN) and NOx emissions, respectively, to very low levels. However, there are concerns regarding the emissions released during the periodic DPF regenerations, which are necessary to clean the filters. The absolute emission levels and the frequency of the regenerations determine the contribution of regenerations, but where they happen (city or highway) is also important due to different contributions to human exposure. In this study, we measured regulated and non-regulated emissions of a Euro 6d-temp vehicle both in the laboratory and on the road. PN and NOx emissions were similar in the laboratory and on-the road, ranging around 1010 p/km and 50 mg/km, respectively. Six regeneration events took place during the 1300 km driven, with an average distance between regeneration events of only 200 km. During regeneration events, the laboratory limits for PN and NOx, although not applicable, were exceeded in one of the two measured events. However, the on-road emissions were below the applicable not-to-exceed limits when regenerations occurred. The weighted PN and NOx emissions over the regeneration distance were approximately two times below the applicable limits. The N2O emissions were <14 mg/km and NH3 at instrument background level (<1 ppm), reaching 8 ppm only during regeneration. The results of this study indicate that due to the short interval between regenerations, studies of diesel vehicles should report the emissions during regeneration events. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
The Influence of Graphene Oxide on Nanoparticle Emissions during Drilling of Graphene/Epoxy Carbon-Fiber Reinforced Engineered Nanomaterials
Atmosphere 2020, 11(6), 573; https://doi.org/10.3390/atmos11060573 - 01 Jun 2020
Viewed by 447
Abstract
Graphene oxide (GO) nanoparticles are increasingly being used to tailor industrial composites. However, despite the advantages, GO has shown conceivable health risks and toxicity to humans and the environment if released. This study investigates the influence that GO concentrations have on nanoparticle emissions [...] Read more.
Graphene oxide (GO) nanoparticles are increasingly being used to tailor industrial composites. However, despite the advantages, GO has shown conceivable health risks and toxicity to humans and the environment if released. This study investigates the influence that GO concentrations have on nanoparticle emissions from epoxy-reinforced carbon fiber hybrid composites (EP/CF) during a lifecycle scenario, that is, a drilling process. The mechanical properties are investigated and an automated drilling methodology in which the background noise is eliminated is used for the nanoparticle emissions measurements. Real-time measurements are collected using a condensation particle counter (CPC), a scanning mobility particle sizer spectrometer (SMPS), a real-time fast mobility particle spectrometer (DMS50) and post-test analytical methods. The results observe that all three nanoparticle reinforced samples demonstrated a statistically significant difference of up to a 243% increase in mean peak particle number concentration in comparison to the EP/CF sample. The results offer a novel set of data comparing the nanoparticle release of GO with varying filler weight concentration and correlating it the mechanical influence of the fillers. The results show that the release characteristics and the influence in particle number concentration are primarily dependent on the matrix brittleness and not necessarily the filler weight concentration within the nanocomposite. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Regional Transport Increases Ammonia Concentration in Beijing, China
Atmosphere 2020, 11(6), 563; https://doi.org/10.3390/atmos11060563 - 28 May 2020
Cited by 1 | Viewed by 638
Abstract
To elucidate the critical factors influencing the ammonia (NH3) concentration in Beijing, this study combined observational analyses, backward trajectory calculations, and meteorology–chemistry coupled simulations to investigate the variations in the NH3 concentration from 11 May to 24 June, 2015. A [...] Read more.
To elucidate the critical factors influencing the ammonia (NH3) concentration in Beijing, this study combined observational analyses, backward trajectory calculations, and meteorology–chemistry coupled simulations to investigate the variations in the NH3 concentration from 11 May to 24 June, 2015. A significant positive correlation was found between the NH3 and PM2.5 concentrations in Beijing. By examining the relationships between meteorological parameters and the NH3 concentration, both near-surface temperature and relative humidity showed positive correlations with the NH3 concentration. The higher NH3 concentrations were usually associated with the warming of the upper atmosphere. Distinct wind directions were noted during the days of the top and bottom 33.3% NH3 concentrations. The top 33.3% concentrations were primarily related to southwesterly winds, while the bottom ones were associated with westerly and northerly winds. Since there are strong NH3 emissions in the southern plains adjacent to Beijing, the regional transport induced by the southerly prevailing winds would increase the NH3 concentration in Beijing significantly. From 23 to 25 May, more than one third of NH3 in Beijing was contributed by the southerly transport processes. Thus, joint efforts to reduce NH3 emissions in the whole Beijing–Tianjin–Hebei region are necessary to regulate the NH3 concentration in Beijing. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
O3 Sensitivity and Contributions of Different NMHC Sources in O3 Formation at Urban and Suburban Sites in Shanghai
Atmosphere 2020, 11(3), 295; https://doi.org/10.3390/atmos11030295 - 17 Mar 2020
Cited by 1 | Viewed by 843
Abstract
Ground-level ozone (O3) pollution is still one of the priorities and challenges for air pollution control in the Yangtze River Delta (YRD) region of China. Understanding the relationship of O3 with its precursors and contributions of different sources in O [...] Read more.
Ground-level ozone (O3) pollution is still one of the priorities and challenges for air pollution control in the Yangtze River Delta (YRD) region of China. Understanding the relationship of O3 with its precursors and contributions of different sources in O3 formation is essential for the development of an O3 control strategy. This study analyzed O3 sensitivity to its precursors using a box model based on online observations of O3, non-methane hydrocarbons (NMHCs), nitrogen oxides (NOx), and carbon monoxide (CO) at an urban site and a suburban site in Shanghai in July 2017. Anthropogenic sources of NMHCs were identified using the positive matrix factorization (PMF) receptor model, and then contributions of different sources in O3 formation were estimated by the observation-based model (OBM). The relative incremental reactivity (RIR) values calculated by the OBM suggest that O3 formation at the urban site was in the NMHC-limited regime, while O3 formation at the suburban site tended between the transition regime and the NMHC-limited regime. Vehicular emission and liquefied petrochemical gas (LPG) use or aged air mass were found to be the two largest contributors at the urban and suburban sites in July, followed by paint and solvent use, and the petrochemical industry. However, from the perspective of O3 formation, vehicular emission and paint and solvent use were the largest two contributors at two sites due to the higher RIR values for paint and solvent use. In addition, the influence of transport on O3 sensitivity was identified by comparing O3 sensitivity at the suburban site across two days with different air mass paths. The result revealed that O3 formation in Shanghai is not only related to local emissions but also influenced by emissions from neighboring provinces. These findings on O3–NMHC–NOX sensitivity, contributions of different sources in O3 formation, and influence of transport could be useful for O3 pollution control in the YRD region. Nevertheless, more quantitative analyses on transport and further evaluation of the uncertainty of the OBM are still needed in future. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Influence of Atmospheric Circulation on Aerosol and its Optical Characteristics in the Pearl River Delta Region
Atmosphere 2020, 11(3), 288; https://doi.org/10.3390/atmos11030288 - 16 Mar 2020
Cited by 2 | Viewed by 723
Abstract
At present, few studies have focused on the impact of circulation patterns on aerosol pollution in the Pearl River delta region (PRD) region based on the objective circulation classification method. Based on PM2.5 observation data, meteorological observation data, Aerosol Robotic Network (AERONET) [...] Read more.
At present, few studies have focused on the impact of circulation patterns on aerosol pollution in the Pearl River delta region (PRD) region based on the objective circulation classification method. Based on PM2.5 observation data, meteorological observation data, Aerosol Robotic Network (AERONET) aerosol observation data and European Center for Medium-Range Weather Forecasting (ECMWF) ERA (European Reanalysis)-Interim data in the PRD during 2013 to 2017, the air pollution level, meteorological conditions, and aerosol optical and radiation characteristics in different circulation patterns are studied in this paper. Using ECMWF ERA-Interim sea level pressure, nine circulation patterns were determined based on the T-mode principal component analysis (PCA) combined with the k-means clustering method. There were significant differences in PM2.5 values under different circulation patterns, indicating that the change of atmospheric circulation is an important factor driving the change of air quality. The prevailing wind in winter (northerly wind) facilitates the transport of pollutants from the north of the PRD and forms severe air pollution, while the prevailing wind in summer (southerly wind) brings clean air from the South China Sea; additionally, a high frequency of precipitation benefits the wet scavenging of pollutants, resulting in improved air quality in the PRD region. The impact of circulation patterns on the AOD (aerosol optical depth) is basically similar to that of the PM2.5 concentration. The study also found that the annual average total radiation was negatively correlated with the annual average PM2.5 concentration. In future, we plan to identify which methods and data are suitable for circulation classification in the PRD region. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Smog Episodes in Poland
Atmosphere 2020, 11(3), 277; https://doi.org/10.3390/atmos11030277 - 12 Mar 2020
Cited by 4 | Viewed by 1096
Abstract
The phenomenon of above-average air pollution, i.e., smog, in urban areas is known. Two types of smog have been described in the literature: London and Los Angeles smog. They differ in the conditions of formation and areas of occurrence. In recent years, the [...] Read more.
The phenomenon of above-average air pollution, i.e., smog, in urban areas is known. Two types of smog have been described in the literature: London and Los Angeles smog. They differ in the conditions of formation and areas of occurrence. In recent years, the phenomenon of smog has also been observed in Poland, where the main reason for poor air quality is exceeding the permissible PM10 concentrations. The main source of particulate matter emissions in Poland is the so-called “low emission”, i.e., released by emitters up to 40 m high, mainly from domestic boilers and traffic. Based on the data from the environmental protection inspection, an analysis was carried out of the impact of atmospheric factors, such as atmospheric pressure and air temperature, on air pollution caused by particulate matter in Poland. Next, data concerning the chemical composition of PM10 particulate matter in Poland was analyzed. In the next stage, tests were carried out on ammonia emissions from biomass and coal combustion processes to determine the source of ammonium ions as a component of particulate matter. The results of analyzes and research allowed us to formulate the thesis about the existence of a specific type of smog called “Polish smog” and determine the conditions for its formation. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Dust Deposition on the Gulf of California Caused by Santa Ana Winds
Atmosphere 2020, 11(3), 275; https://doi.org/10.3390/atmos11030275 - 10 Mar 2020
Cited by 1 | Viewed by 808
Abstract
Numerical simulations revealed a profound interaction between the severe dust storm of 2007 caused by Santa Ana winds and the Gulf of California. The weather research and forecasting model coupled with a chemistry module (WRF-CHEM) and the hybrid single-particle Lagrangian integrated trajectory model [...] Read more.
Numerical simulations revealed a profound interaction between the severe dust storm of 2007 caused by Santa Ana winds and the Gulf of California. The weather research and forecasting model coupled with a chemistry module (WRF-CHEM) and the hybrid single-particle Lagrangian integrated trajectory model (HYSPLIT) allowed for the estimation of the meteorological and dynamic aspects of the event and the dust deposition on the surface waters of the Gulf of California caused by the erosion and entrainment of dust particles from the surrounding desert regions. The dust emission rates from three chosen areas (Altar desert, Sonora coast, and a region between these two zones) and their contribution to dust deposition over the Gulf of California were analyzed. The Altar Desert had the highest dust emission rates and the highest contribution to dust deposition over the Gulf of California, i.e., it has the most critical influence with 96,879 tons of emission and 43,539 tons of dust deposition in the gulf. An increase of chlorophyll-a concentrations is observed coinciding with areas of high dust deposition in the northern and western coast of the gulf. This kind of event could have a significant positive influence over the mineralization and productivity processes in the Gulf of California, despite the soil loss in the eroded regions. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Pollution Transport Patterns Obtained Through Generalized Lagrangian Coherent Structures
Atmosphere 2020, 11(2), 168; https://doi.org/10.3390/atmos11020168 - 06 Feb 2020
Cited by 1 | Viewed by 875
Abstract
Identifying atmospheric transport pathways is important to understand the effects of pollutants on weather, climate, and human health. The atmospheric wind field is variable in space and time and contains complex patterns due to turbulent mixing. In such a highly unsteady flow field, [...] Read more.
Identifying atmospheric transport pathways is important to understand the effects of pollutants on weather, climate, and human health. The atmospheric wind field is variable in space and time and contains complex patterns due to turbulent mixing. In such a highly unsteady flow field, it can be challenging to predict material transport over a finite-time interval. Particle trajectories are often used to study how pollutants evolve in the atmosphere. Nevertheless, individual trajectories are sensitive to their initial conditions. Lagrangian Coherent Structures (LCSs) have been shown to form the template of fluid parcel motion in a fluid flow. LCSs can be characterized by special material surfaces that organize the parcel motion into ordered patterns. These key material surfaces form the core of fluid deformation patterns, such as saddle points, tangles, filaments, barriers, and pathways. Traditionally, the study of LCSs has looked at coherent structures derived from integrating the wind velocity field. It has been assumed that particles in the atmosphere will generally evolve with the wind. Recent work has begun to look at the motion of chemical species, such as water vapor, within atmospheric flows. By calculating the flux associated with each species, a new effective flux-based velocity field can be obtained for each species. This work analyzes generalized species-weighted coherent structures associated with various chemical species to find their patterns and pathways in the atmosphere, providing a new tool and language for the assessment of pollutant transport and patterns. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Scavenging of Sub-Micron to Micron-Sized Microbial Aerosols during Simulated Rainfall
Atmosphere 2020, 11(1), 80; https://doi.org/10.3390/atmos11010080 - 09 Jan 2020
Cited by 1 | Viewed by 1050
Abstract
The processes removing aerosols from the atmosphere during rainfall are generically referred to as scavenging. Scavenging influences aerosol distributions in the atmosphere, with consequent effects on cloud properties, radiative forcing, and human health. In this study, we investigated the below-cloud scavenging process, specifically [...] Read more.
The processes removing aerosols from the atmosphere during rainfall are generically referred to as scavenging. Scavenging influences aerosol distributions in the atmosphere, with consequent effects on cloud properties, radiative forcing, and human health. In this study, we investigated the below-cloud scavenging process, specifically focusing on the scavenging of 0.2 to 2 µm-sized microbial aerosols by populations of water drops with average diameters of 3.0 and 3.6 mm. Rainfall was simulated in convective boundary layer air masses by dispensing the water drops from a 55 m bridge and collecting them at ground level. Particles and microbial cells scavenged by the water drops were visualized, enumerated, and sized using scanning electron and epifluorescence microscopy. Aerosolized particles and DNA-containing microbial cells of 2 µm diameter were scavenged at efficiencies similar to those reported previously in empirical studies; however, the efficiencies derived for smaller aerosols were significantly higher (one to three orders of magnitude) than those predicted by microphysical modeling. Application of the derived scavenging efficiencies to cell data from rainfall implies that, on average, approximately 50 to 70% of the 1 µm microbial cells in the precipitation originated from within the cloud. Further study of submicron to micron-sized aerosol scavenging over a broader raindrop size distribution would improve fundamental understanding of the scavenging process and the capacity to estimate (bio)aerosol abundances in the source cloud through analysis of rainfall. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
A New Geochemical Method for Determining the Sources of Atmospheric Particles: A Case Study from Gannan, Northeast China
Atmosphere 2019, 10(10), 632; https://doi.org/10.3390/atmos10100632 - 20 Oct 2019
Cited by 1 | Viewed by 1143
Abstract
The geochemical characteristics of atmospheric deposition can help trace the origin and assess the impacts of pollutants. Northeast China has always been a region seriously affected by sandstorms. This study aims to explain the potential source of sandstorms in Gannan County, Heilongjiang Provence, [...] Read more.
The geochemical characteristics of atmospheric deposition can help trace the origin and assess the impacts of pollutants. Northeast China has always been a region seriously affected by sandstorms. This study aims to explain the potential source of sandstorms in Gannan County, Heilongjiang Provence, by collecting dust and analyzing geochemistry in one year where there is no significant industrial or anthropogenic pollution. Input fluxes of deposition show that Zn and Mn were more prevalent (36.7 g·hm−2·a−1 and 77.93 g·hm−2·a−1, respectively) than other elements. The geochemical composition of atmospheric deposition samples from 17 collection points in Gannan County were determined with regard to 20 elements including nine heavy metals, two metalloids, three nonmetallic elements, a transition metal, and five other major elements. The discriminate function (DF) and chemical index of alteration (CIA) indices indicate that Gannan County (agricultural production area) and Harbin (densely inhabited district) have similar geochemical characteristics of dry deposition. The integration of Na/Al and Ca/Mg ratios with an air mass back-trajectories model shows effects from Russian dust sources (36.6%) and from the northwest desert of China (13.3%). The results will assist in developing strategies for reducing dry deposition pollution inputs to agricultural soils in the area and will effectively target policies to protect soils from long-term contaminant accumulation. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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Open AccessArticle
Virus-Like Particle Production in Atmospheric Eubacteria Isolates
Atmosphere 2019, 10(7), 417; https://doi.org/10.3390/atmos10070417 - 19 Jul 2019
Cited by 1 | Viewed by 1733
Abstract
Culturable eubacterial isolates were collected at various altitudes in Earth’s atmosphere, including ~1.5 m above ground in Tallahassee, FL, USA; ~10.0 m above sea level over the mid-Atlantic ridge (~15° N); ~20 km above ground over the continental United States; ~20 km above [...] Read more.
Culturable eubacterial isolates were collected at various altitudes in Earth’s atmosphere, including ~1.5 m above ground in Tallahassee, FL, USA; ~10.0 m above sea level over the mid-Atlantic ridge (~15° N); ~20 km above ground over the continental United States; ~20 km above sea level over the Pacific Ocean near southern California; and from the atmosphere of Carlsbad Cavern, Carlsbad Cavern National Park, NM, USA. Isolates were screened for the presence of inducible virus-like particles (VLP) through the use of mitomycin C and epifluorescent direct counts. We determined that 92.7% of the isolates carried inducible VLP counts in exposed versus non-exposed culture controls and that the relationship was statistically significant. Further statistical analyses revealed that the number of isolates that demonstrated VLP production did not vary among collection sites. These data demonstrate a high prevalence of VLP generation in isolates collected in the lower atmosphere and at extreme altitudes. They also show that species of eubacteria that are resistant to the rigors of atmospheric transport play a significant role in long-range atmospheric inter- and intra-continental dispersion of VLP and that long-range atmospheric transport of VLP may enhance rates of evolution at the microbial scale in receiving environments. Full article
(This article belongs to the Special Issue Emissions, Transport and Fate of Pollutants in the Atmosphere)
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