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Air pollution poses major threat to premature mortality (Lelieveld, Evans, Fnais, Giannadaki, Pozzer, Nature, 525:367–371, (2015), [8]) but its levels over \(80\%\) of cities are unhealthy (WHO: WHOs urban ambient air pollution database - update 2016. In: World Health Organization (2016). www.who.int/phe, Cited 1 July 2017, [15]). Although large-scale computational fluid dynamics (CFD) models are the common research solutions to detailed air quality studies (Russell, Annu Rev Energy Environ, 22:537–588, (1997), [12]), analytical models offer quick screening tools that are surrogates for prohibitively expensive sensitivity tests in practice (Moonen, Allegrini, Environ Model Softw, 72:77–91, (2015), [9]). The Gaussian models, which are analytical tools developed based on open terrain and chemically inert pollutants, have been well received in the industry for decades (Roberts, Proc Roy Soc Lond A, 104:640–654, (1923), [11]). Their results for chemically reactive pollutants over urban areas must be interpreted cautiously.

A framework based on a mixed reality simulator for coordinating teams of autonomous Unmanned Aerial Vehicles (UAVs) is been developed. This framework would serve as a tool to facilitate crossing the reality gap for different applications; particularly when using these UAVs teams for air pollution monitoring and measurement. The system is built on a co-evolutionary simulator that makes use of data transmitted from some real UAVs to integrate them within a team of simulated UAVs. The system allows the progressive increase of the number of real UAV in the team. This facilitates the setting-up of a single UAV control system and also of the UAV collaboration schemes for different scenarios. A specific implementation of this system focussed on mapping the pollutant dispersion of a plume in the atmosphere is presented. Implementing an appropriate pollution dispersion model within the simulator is a key aspect of the system. This model should require few computational resources, should be easy to adapt in real time to ambient changes, and it should have a fair accuracy.

We report a study of the particulate matter emissions related to the 2015 fire outbreak at a fuel tank storage facility located at Santos, a coastal city in Brazil. The facility, managed by the company Ultracargo, had oil tanks (filled with gasoline and ethanol) destroyed by fire that lasted more than a week, between 2nd and 9th April. In this article, we present the atmospheric concentration analysis of particulate matter (PM10) measured over the entire month of April 2015 by the 2 closest stations that integrate the air quality monitoring system of the São Paulo State Environmental Company (CETESB). The results were compared with similar data from the same period of the yesteryear (April 2014). The results were also complemented by the air masses trajectories over the region (obtained with HYSPLIT/NOAA software). Our results do indicate a subtle increase in the particulate concentration during the days of the fire, followed by a fast dissipation over the subsequent weeks. The observed plume dispersion discussion is made considering the meteorological patterns of the region and other environmental and health reported impacts related to the accident.

As part of the Observations and Modeling of the Green Ocean Amazon (GoAmazon 2014/5) Experiment, detailed aerosol and trace gas measurements were conducted near Manaus, a metropolis located in the central Amazon Basin. Measurements of aerosol particles and trace gases were done downwind Manaus at the sites T2 (Tiwa Hotel) and T3 (Manacapuru), at a distance of 8 and 70 km from Manaus, respectively. Based on in-plume measurements closer to Manaus (site T2), the chemical signatures of city emissions were used to improve the interpretation of pollutant levels at the T3 site. We derived chemical and physical properties for the city's atmospheric emission ensemble, taking into account only air masses impacted by the Manaus plume at both sites, during the wet and dry season Intensive Operating Periods (IOPs). At T2, average concentrations of aerosol number (CN), CO and SO2 were 5500 cm−3 (between 10 and 490 nm), 145 ppb and 0.60 ppb, respectively, with a typical ratio ΔCN/ΔCO of 60–130 particles cm−3 ppb−1. The aerosol scattering (at RH < 60%) and absorption at 637 nm at T2 ranged from 10 to 50 M m−1 and 5–10 M m−1, respectively, leading to a mean single scattering albedo (SSA) of 0.70. In addition to identifying periods dominated by Manaus emissions at both T2 and T3, the plume transport between the two sampling sites was studied using back trajectory calculations. Results show that the presence of the Manaus plume at site T3 was important mainly during the daytime and at the end of the afternoons. During time periods directly impacted by Manaus emissions, an average aerosol number concentration of 3200 cm−3 was measured at T3. Analysis of plume evolution between T2 and T3 indicates a transport time of 4–5 h. Changes of submicron organic and sulfate aerosols ratios relative to CO (ΔOA/ΔCO and ΔSO4/ΔCO, respectively) indicate significant production of secondary organic aerosol (SOA), corresponding to a 40% mass increase in OA and a 30% in SO4 mass concentration. Similarly, during air mass arrival at T3 the SSA increased to 0.83 from 0.70 at T2, mainly associated with an increase in organic aerosol concentration. Aerosol particle size distributions show a strong decrease in the Aitken nuclei mode (10–100 nm) during the transport from T2 to T3, in particular above 30 nm, as a result of efficient coagulation processes into larger particles. A decrease of 30% in the particle number concentration and an increase of about 50 nm in geometric mean diameter were observed from T2 to T3 sites. The study of the evolution of aerosol properties downwind of the city of Manaus improves our understanding of how coupling of anthropogenic and biogenic sources may be impacting the sensitive Amazonian atmosphere. © 2018 The Authors

Dust emissions from unpaved roads are one of the main pollutants affecting air quality around the world. As part of initial air quality studies in Tuxtla Gutiérrez (TGZ), Chiapas, Mexico, urban aeolian emission events from unpaved roads and simple meteorological inputs were measured in February 2014 at two different sites located within the city to characterize emissions for representative road conditions and to produce Industrial Source Complex (ISC3) model inputs. Emissions of particulate matter of aerodynamic diameter less than 10 µm (PM10) were determined for eight wind erosion events. PM10 concentrations were measured downwind from sites using a Minivol sampler during February and March 2014. Three high PM10 concentration scenarios, associated with unstable conditions generated by cold fronts (CF) were selected to simulate dust plume dispersion to identify impacted areas. Results show that unpaved roads represent a potential source of dust that affect air quality of urban regions; in this study generating emissions ≥ 1.92 × 10−3 g·m−2·s−1 when winds ≥6 m·s−1 were present. Air pollution events that exceed the Mexico national standard for 24-h average PM10 concentration (≥75 µg·m−3) were observed, impacting different areas in the city, representing a risk to human health. This demonstrates the influence of CF over southern Mexico, generating high PM10 concentrations in urban regions.

This work evaluated the volatile organic compound (VOC) emissions by a landfill located in Niterói City, RJ, Brazil. Twenty six samples were collected in 2009 using a 30 L cylindrical polyvinyl chloride (PVC) flux chamber. The results indicated an elevated emission of 1980 kg km-2 h-1. A Gaussian plume dispersion model was used to evaluate the transport of pollutants and values of 525 µg m-3 for VOC were found at ca. 500 m from the landfill. The emissions were also compiled with meteorological data, using the OZIPR (Ozone Isopleth Package for Research) trajectory model coupled with SAPRC (Statewide Air Pollution Research Center) chemical mechanism to demonstrate the impact on tropospheric ozone. The results indicated a 1000% increase in ozone in the region of the landfill when compared to the ozone values for the metropolitan region of Rio de Janeiro. The results show that it is necessary greater attention to the political management of municipal solid waste in Brazil. Este trabalho avaliou as emissões de compostos orgânicos voláteis (VOC) de um aterro controlado localizado na cidade de Niterói, RJ, Brasil. Foram coletadas 26 amostras em 2009 usando uma câmara de fluxo de cloreto de ponivinila (PVC) cilíndrica de 30 L. Os resultados indicaram uma elevada emissão de 1980 kg km-2 h-1. Um modelo de dispersão Gaussiano foi usado para avaliar o transporte dos poluentes e valores de 525 µg m-3 para VOC foram encontrados a ca. 500 m do aterro. As emissões também foram compiladas com dados meteorológicos usando o modelo de trajetórias OZIPR (Ozone Isopleth Package for Research) acoplado ao modelo químico SAPRC (Statewide Air Pollution Research Center) para avaliar o impacto na formação de ozônio troposférico. Os resultados indicaram um aumento de mais de 1000% nos níveis de ozônio comparados com valores da região metropolitana do Rio de Janeiro. Os resultados indicaram que é necessária uma maior atenção dos órgãos governamentais no gerenciamento dos resíduos sólidos no Brasil.

A study was conducted to estimate the changes in wintertime visual air quality in Dallas-Fort Worth (DFW) that might occur due to proposed reductions in SO2 emissions at two steam electric generating plants in eastern Texas, each over 100 km from the city. To provide information for designing subsequent investigations, the haze was characterized broadly during the first year of the study. Meteorological data acquired then demonstrated that, during haze episodes, emissions from only one of the two plants were likely to be transported directly to DFW. Therefore, the second year of the study was centered on just one of the power plants. Air quality was then characterized within the urban area and at rural locations that would be upwind and downwind of the plant during transport to DFW. An instrumented aircraft measured plume dispersion and the air surrounding the plume on selected days. A mathematical model was used to predict the change that would occur in airborne particulate matter concentrations in DFW if SO2 emissions were reduced to reflect the proposed limitations. The contribution of particles in the atmosphere to light extinction was estimated, and simulated photographs were produced to illustrate the visibility changes. The study concluded that the proposed emission reductions would, at most, subtly change perceived wintertime visibility.

We developed an exposure estimation model for an epidemiological study on the effect of traffic-related air pollutants on respiratory diseases. The model estimates annual average outdoor concentration of nitrogen oxides (NOx) and elemental carbon (EC). The model is composed of three nested plume dispersion type submodels treating different spatial scales from a few meters to tens of kilometers. The emissions from road traffic was estimated at high spatial resolution along the paths of roads taking into account the effects of individual building shape and traffic signals to secure accuracy near trunk roads where most of the subjects of the epidemiological study resided. Model performance was confirmed by field measurements at permanent local government stations and purpose-built temporary stations; the latter supplemented roadside monitoring points and provided EC concentrations, which are not measured routinely. We infer that EC emissions were underestimated by using the available database because there were significant contributions to EC concentrations from sources that did not emit much NOx. An adjustment concentration yielded good agreement between model estimates and field measurements.

The vertical allocation of emissions has a major impact on results of Chemistry Transport Models. However, in Europe it is still common to use fixed vertical profiles based on rough estimates to determine the emission height of point sources. This publication introduces a set of new vertical profiles for the use in chemistry transport modeling that were created from hourly gridded emissions calculated by the SMOKE for Europe emission model. SMOKE uses plume rise calculations to determine effective emission heights. Out of more than 40 000 different vertical emission profiles 73 have been chosen by means of hierarchical cluster analysis. These profiles show large differences to those currently used in many emission models. Emissions from combustion processes are released in much lower altitudes while those from production processes are allocated to higher altitudes. The profiles have a high temporal and spatial variability which is not represented by currently used profiles. © 2010 Published by Elsevier Ltd.

The vertical allocation of emissions has a major impact on results of Chemistry Transport Models. However, in Europe it is still common to use fixed vertical profiles based on rough estimates to determine the emission height of point sources. This publication introduces a set of new vertical profiles for the use in chemistry transport modeling that were created from hourly gridded emissions calculated by the SMOKE for Europe emission model. SMOKE uses plume rise calculations to determine effective emission heights. Out of more than 40 000 different vertical emission profiles 73 have been chosen by means of hierarchical cluster analysis. These profiles show large differences to those currently used in many emission models. Emissions from combustion processes are released in much lower altitudes while those from production processes are allocated to higher altitudes. The profiles have a high temporal and spatial variability which is not represented by currently used profiles. © 2010 Published by Elsevier Ltd.

Maintenance of Department of Defense (DoD) weapon systems, conducting battlefield training exercises as well as meeting military construction and/or demolition schedules, invariably generate fugitive air emissions, many of which are visible. Although there is no codified federal method for quantifying fugitive emissions opacity, many state and local air regulatory agencies have instituted enforceable fugitive emission opacity standards at DoD facilities. The current study focused on comparing the performance of the digital opacity compliance system (DOCS) with U.S. Environment Protection Agency Method 9 (Method 9) certified human observers in quantifying the visible opacity associated with fugitive emissions produced using a commercial fog generator. By systematically repositioning both DOCS cameras and Method 9-certified observers during field testing, differences in method performance as a function of observational locations were documented. At both the 30- and 300-ft off-set distances, opacity levels reported by the DOCS technology and Method 9-certified smoke readers were found to be statistically different at the 99% confidence level. Alternatively, at the 90- and 150-ft off-set distances, results suggested that there was an insignificant difference at the 99% confidence level between the two methods. Comparing the magnitude of the each method's standard deviation suggested that, at the 30-ft off-set distance, the DOCS technology was consistently more precise than Method 9-certified readers regardless of the observer's downwind distance. However, at the 90, 150, and 300-ft off-set distances, method precision seemed to vary as a function of both off-set and downwind distance. The primary factor affecting the consistency in opacity measurements appeared to be the impact of ground-level air turbulence on fog plume dispersion and transport. Field observations demonstrated that localized wind shear played a critical and decisive role in how and to what extent fugitive emissions opacity could be determined, regardless of the method selected.

The present paper describes the application of the CALMET meteorological model and CALPUFF plume dispersion model to the Yatagan district to study the impact of Yatagan Power Plant emissions on the SO2 levels on December 2000 in the region. Results indicate that SO2 concentrations over the city depend strongly on advected emissions from the power plant and on the local variation of the wind field and limited vertical mixing conditions. It is found that South Westerly and light winds and the night time surface inversion layers lead to accumulation of pollutants coming from the power plant over the Yatagan district. The results are compared with the observations obtained from Local Environmental Authorities of Mugla. The simulation results indicate that the maximum ground level concentrations were found northeast from the source, which agrees with the measurements, but differ in terms of magnitudes.

The goal of this research effort was to demonstrate a capability for analyzing emergency response issues resulting from accidental or mediated airborne toxic releases in an urban setting. In the first year of the program, the authors linked a system of fluid dynamics, plume dispersion, and vehicle transportation models developed at Los Alamos National Laboratory to study the dispersion of a plume in an urban setting and the resulting exposures to vehicle traffic. This research is part of a larger laboratory-directed research and development project for studying the relationships between urban infrastructure elements and natural systems.

This work introduces the project “Meso-Meteorological Cycles of Air Pollution in the Iberian Peninsula” (MECAPIP). It reviews some aspects which influence the behavior of pollutants in Southwestern Europe, presents an overview of the experimental programs now under way and identifies some of the modelling needs. The project leads the CEC efforts to develop a comprehensive program to characterize the Physico-chemical behavior of polluted airmasses in the Mediterranean Basin and to provide the necessary inputs for more realistic modelling of local episodic conditions and the long-range transmission of pollutants over the whole of Europe.

A data base representing the results of the Lompoc Valley diffusion experiment is described in detail, outlining formats and defining the contents of the data set. Preliminary analyses are performed, showing concentrations, trajectories and plume widths of a tracer gas plume released from the Hypergolic Stockpile and Storage Facility at Vandenberg Air Force Base, California, and estimating the effects of a potential release of fuel or oxidizer. Future analysis plans are outlined Prepared for: USAF Space Division (SSD/CLGR), Los Angeles, CA. http://archive.org/details/lompocvalleydiff00skup MPIR FY76169000643 NA Approved for public release; distribution is unlimited.

A tracer technique using certain of the rare earth elements which are easily activated by neutrons has been developed for the analysis of air pollution problems. Studies employing these tracers were made to determine whether the available meteorological dispersion models can be used effectively to describe pollution emissions from selected industries in the vicinity of Albany, Oregon. The Gaussian plume model was found to be satisfactory for the moderately intense turbulence fields which characterize Stability Types B, C, and D, including cases in which the pollution was trapped by an inversion layer aloft. For sources near ground level, however, it was necessary to make allowance for urban influences on plume dispersion. A box model best described the observed dispersal pattern when the upward penetration of the very intense turbulence of Stability Type A was limited by an inversion layer aloft. These meteorological models were applied using a “blind” experimental procedure to predict the emission rates ...

Recent developments in puff methods for simulating plume behavior are discussed. Modifications to the basic methodologies are introduced which make it more generally applicable to non-stationary and non-homogeneous conditions, as well as calm wind situations. The modifications described should also allow significant reductions of computer storage and running time requirements. The algorithm presented could easily be extended to the treatment of segment or area sources. The model accurately reproduces the analytical solution to the steady-state Gaussian plume equation.

This paper presents a comparative analysis of the results of 15 air quality model performance evaluation studies involving 35 rural, urban, complex-terrain and regional models. Common themes are identified, and their implications for the improvement of model performance and usage discussed. Among study findings are the following: 1. (a) flat-terrain rural models nearly always predict the second highest concentrations within a factor of two (often less), with no evidence of systematic over- or underprediction, but some models may underpredict the highest concentrations by more than a factor of two at distances far downwind (20 km); 2. (b) none of the models accurately predicts spatial patterns of ⩽ 24 h-averaged concentrations, and while increasing the averaging time from 24 h to annual improves performance for some models, it does not appear to do so for flat-terrain rural models; and 3. (c) while some models appear to predict more frequent concentrations (e.g. 5th- or 10th high, 95th percentile) better than they do the highest concentrations (e.g. 2nd high), no overall, systematic tendency is evident. Although definitive proof is beyond the scope of this paper, the hypothesis is offered that the observed performance of flat-terrain rural models may be attributable, in part, to slower-than-actual cross-sectional plume dispersion under neutral and stable atmospheric conditions, particularly in the vertical direction, but possibly also in the horizontal.

It is demonstrated that a fluctuating plume dispersion model can be used to give realistic estimates of odour frequencies around a point source, when the odour threshold of the chimney gases is determined by sensory methods ( Lindvall , 1970). The theoretical calculations are compared with observational results from a field experiment at and around a sulphate pulp factory in Sweden. Trained observers were used, making a large number of instantaneous observations of odour in the outdoor air at a variety of locations around the factory.

Initiatives to displace petroleum and climate change mitigation have driven a recent increase in space heating with biomass combustion. However, there is ample evidence that biomass combustion emits significant quantities of health damaging pollutants. We investigated the near-source micro-environmental air quality impact of a biomass-fueled combined heat and power system equipped with an electrostatic precipitator (ESP) in Syracuse, NY. Two rooftop sampling stations with PM 2.5 and CO 2 analyzers were established in such that one could capture the plume while the other one served as the background for comparison depending on the wind direction. Four sonic anemometers were deployed around the stack to quantify spatially and temporally resolved local wind patterns. Fuel-based emission factors were derived based on near-source measurement. The Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model was then applied to simulate the spatial variations of primary PM 2.5 without ESP. Our analysis shows that the absence of ESP could lead to an almost 7 times increase in near-source primary PM 2.5 concentrations with a maximum concentration above 100 μg m −3 at the building rooftop. The above-ground “hotspots” would pose potential health risks to building occupants since particles could penetrate indoors via infiltration, natural ventilation, and fresh air intakes on the rooftop of multiple buildings. Our results demonstrated the importance of emission control for biomass combustion systems in urban area, and the need to take above-ground pollutant “hotspots” into account when permitting distributed generation. The effects of ambient wind speed and stack temperature, the suitability of airport meteorological data on micro-environmental air quality were explored, and the implications on mitigating near-source air pollution were discussed.

Mathematical models used to simulate photochemical urban air pollution are generally based upon the solution of the atmospheric diffusion equation, which describes the rate of change of chemical species in each cell of a three-dimensional grid-mesh. In such models, point source emissions are assumed to be immediately dispersed into a grid cell. This approximation generally leads to an overestimation of plume dispersion and thus considerably affects the accurate treatment of photochemical kinetic processes.