International Journal of Environment and Pollution (27 papers in press)
Simulating large emitters using CMAQ and a local scale finite element model: analysis of the surroundings of Barcelona
by Albert Oliver, Raul Arasa, Agusti Pérez-Foguet, Mª Ángeles Gonzalez
Abstract: In this work, we present a novel approach to simulate large emitters on the microscale. The main idea is to combine a nested grid approach and a finite element model to simulate the subgrid scale. The nested grid system consists of the mesoscale meteorological model WRF-ARW, the Air Emission Model of Meteosim (AEMM), and the air quality model CMAQ. The subgrid scale is simulated using an adaptive, Eulerian, non-steady finite element model. The results from the nested grid simulation are used as initial and boundary conditions in the subgrid model, making this approach one-way. A simulation has been carried out in the surroundings of Barcelona, where an important contributor to the sulphur dioxide levels is considered. The simulations were carried out for one episode with high levels of sulphur dioxide. The time period of the simulation was 48 hours with a 24-hour spin-up.
Keywords: AQM; air quality modelling; subgrid scale plume modelling; nested
grid modelling; dispersion models; large emitters; local scale; microscale;
plume rise; WRF; weather research & forecasting model; AEMM; air emission
model of Meteosim; CMAQ; community multi-scale air quality; FEM; finite
element method; PinG; plume-in-grid; one-way nesting; Barcelona; forecasting;
Lagrangian simulations of the plume rise in strong capping inversion
by Enrico Ferrero, Stefano Alessandrini, Domenico Anfossi
Abstract: We have performed new investigations applying our Lagrangian algorithm described by Alessandrini et al. (2013) to simulate the plume rise in a convective boundary layer capped by a strong inversion layer. We tested our model with the results of a water tank experiment (Weil et al. 2002). For each case, we compared the simulated and measured mean height, horizontal and vertical plume standard deviations, and the entrapment (the fraction of the plume that remains captured above the temperature inversion layer located at the top of the boundary layer). The results show that the model is able to reproduce the main characteristics of the plume accurately.
Keywords: Lagrangian model; plume rise; entrapment.
EDTA and citrate impact on heavy metals phytoremediation using Paulownia hybrids
by Maria Geneva, Kameliya Miladinova-Georgieva, Katya Ivanova, Teodora Georgieva, Petar Petrov, Ira Stancheva, Yuliana Markovska
Abstract: The influence of the EDTA and citrate addition to the industrially polluted soil on phytoextraction of heavy metals, leaf anatomy, and gas exchange parameters of two Paulownia hybrid lines (Paulownia tomentosa x fortunei - TF 01 and Paulownia elongata x fortunei - EF 02) was evaluated. Both lines were accumulators of Cu, Zn and Cd because bioaccumulation factor values were higher than 1.00. The levels of heavy metal accumulation in shoots indicated that both hybrids may be used for phytoremediation, since transfer factors for Pb and Zn in hybrid TF 01 were higher than 1.00, and in hybrid EF 02 for Zn only. Application of EDTA produced heavy metal accumulation in hybrid lines higher than those obtained with citrate. Treatment with 1 mM EDTA displayed a protective effect on leaf development in both lines and overcame damage in the morphological structure caused by heavy metal stress
Keywords: Paulownia elongata x fortunei - EF 02; Paulownia tomentosa x fortunei - TF 01; phytoextraction; mesophyll thickness; gas exchange.
Assessment of ambient air quality around mines, in buffer zone and along ore transportation routes in iron ore mining region of Goa: emphasis on spatial distributions and seasonal variations
by Gurdeep Singh, Atahar Perwez
Abstract: Monitoring was done with respect to PM10, PM2.5, SO2 and NOX at 34 stations selected in mines, buffer zone and along ore transportation routes. Particulate pollutants (PM10 and PM2.5) were observed as the major pollutants in the study area, and ore transportation was identified as the most polluting activity. The calculated values of AQI also evidenced the same. The concentrations of PM10 and PM2.5 along the ore transportation routes were observed as 130
Keywords: ambient air quality; assessment; air quality index; ANOVA; correlation; mining; NOX; PM10; PM2.5; ratio; SO2; transportation routes.
Using 137Cs and 210Pbex to quantify the effects of land use on soil organic carbon and total nitrogen in the subtropical Dianchi watershed, southwest China
by Mingli Zhang, Xia Wang, Biao Xie, Yong Zhang
Abstract: The conversion from forest to agricultural land in the last three decades represents a significant shift in land use in China. However, few direct measurements have been made to investigate the dynamic processes of soil organic carbon (SOC) and total nitrogen (TN) under land use change. Our results showed that converting forest to grassland and farmland led to an increase in SOC content, and decreases of TN concentration and C:N ratio in the topsoil. The erosion rate and nutrient loss estimated by 137Cs showed highest under farmland. The highest nutrient losses were found in cultivated farmland, with 4.08 and 0.40 t km-2 year-1 for SOC and TN, respectively. We conclude that forest system could be an effective strategy to improve SOC stocks in the subtropical Dianchi watershed. The accumulation of nitrogen in cultivated farmland soils poses a potential threat to nearby Dianchi Lake.
Keywords: soil organic carbon; total nitrogen; C:N ratio; 137Cs and 210Pbex; Dianchi watershed.
CFD modelling of dispersion in neutral and stably stratified atmospheric boundary layers: results for Prairie Grass and Thorney Island
by Rachel Batt, Simon Gant, Jean-Marc Lacome, Benjamin Truchot, Harvey Tucker
Abstract: It is a known problem that CFD models using the standard k-ε turbulence model do not maintain the correct Atmospheric Boundary Layer (ABL) profiles along a flat, unobstructed domain. The present work examines the impact of these errors in the ABL profiles on dispersion model predictions for three field-scale experiments from the Prairie Grass and Thorney Island datasets. The modified ABL profiles produced by the CFD model in the Prairie Grass experiments result in differences in the predicted concentrations of up to a factor of two, as compared to a reference model. For the Thorney Island experiment, the results for the standard k-ε turbulence model are sensitive to the ground surface roughness, and problems are identified in relation to the grid resolution near the ground. Industrial risk assessments involving atmospheric dispersion of toxic or flammable substances using CFD models should take into account these limitations of the k-ε turbulence model.
Keywords: CFD; atmospheric boundary layers; passive gas; dense gas; dispersion; Prairie Grass; Thorney Island.
Factors affecting the leaching behaviour of magnesium phosphate cement-stabilised/solidified Pb-contaminated soil. Part I: water-to-solid ratio and Pb concentration
by Ping Wang, Qiang Xue, Jiang-shan Li, Ting-Ting Zhang, Shan-Yong Wang
Abstract: Magnesium phosphate cement (MPC) is widely used to effectively stabilise/solidify (S/S) heavy-metal-contaminated soils, and leachability is the most important parameter for MPC-treated metal-contaminated soil. However, various factors in the S/S process, such as the metal concentration in the soil and the water-to-solid (W/S) ratio of the S/S paste treated using MPC, can greatly affect the leaching behaviour of heavy metals in the S/S monolith. The Toxicity Characteristic Leaching Procedure (TCLP) and semi-dynamic leaching tests were conducted to investigate the effects of metal concentrations and W/S ratios on the leaching behaviour of MPC-treated Pb-contaminated soil. Results showed that the Pb concentration and W/S ratios change the leaching behaviour and leaching mechanisms of MPC-treated Pb-contaminated soil, and the optimum W/S ratio 0.50 was obtained when MPC was used to stabilise Pb-contaminated soils.
Keywords: stabilisation/solidification; leaching; water-to-solid ratio; magnesium phosphate cement.
Special Issue on: HARMO17 Harmonisation within Atmospheric Dispersion Modelling for Regulatory Purposes
Evaluation of some blood parameters in parallel with expression of P53 and IL-6 in industrial pollution exposed subject
by Hadis Ahmadirad, Mohammad Reza Hajizadeh, Gholamhossien Hassanshahi, Mehdi Mahmoodi
Abstract: Industrial pollution, including trace elements, has the ability to cause cancer and inflammatory diseases in humans. Therefore, this study was aimed to determine inflammatory and cancer biomarkers, such as P53 and IL-6, in parallel with some other blood biochemical parameters in normal subjects and people who were exposed to industrial trace elements. The studied population included 45 workers who were exposed to trace elements and 45 control group members. Blood biochemical parameters such as CBC were examined by cell counter, and gene expression of P53 and IL-6 was detected by real time PCR technique; liver enzymes were also measured by a Hitachi 912 analyser. Our findings showed that the gene expression IL-6 (as an indicator of inflammation) was significantly increased in workers who were exposed to pollution, and P53 was also considerably increased (as an indicator of DNA damage). The levels of liver enzymes SGOT and SGPT, along with the number of both red blood cells and white blood cells, were also increased; however we observed no significant changes in these factors. The results showed that the exposure to industrial pollution leads to increased expression of P53 and IL-6. This evidence may confirm a potential role for pollution and trace elements in developing inflammatory diseases and cancer in workers.
Keywords: industrial pollution; trace elements; IL-6; p53.
Model intercomparison and validation of ADMS plume chemistry schemes
by Stephen Smith, Jenny Stocker, Martin Seaton, David Carruthers
Abstract: Two schemes for the determination of NO2 concentrations in the atmospheric dispersion model ADMS are evaluated using data from two sites in Alaska. Both schemes take account of the rate of oxidation of NO and photolysis of NO2 in the plume using identical chemical formulations. The differences lie in the approaches used for the entrainment and mixing of ambient ozone into the plume. In the standard scheme it is assumed that ozone is mixed instantaneously into the plume at source; in the entrainment limited scheme ozone is entrained into the plume at a rate determined by the rate of dilution of the instantaneous plume. A methodology comprising a scatter plot of the ratio of modelled to observed NO2 vs. modelled to observed NOx is used to distinguish errors in the chemistry schemes from errors in the prediction of NOx. Both schemes show good performance statistics with the standard scheme predicting higher NO2 concentrations.
Keywords: plume chemistry; nitrogen dioxide; ADMS; validation; model intercomparison.
Special Issue on: Dioxins, Sources and Effects, Formation and Abatement
GC-HRMS analysis for POPs and new POPs with GC-Tof/MS techniques
by Takumi Takasuga
Special Issue on: HARMO 17
Influence of vehicle-induced turbulence on pollutant dispersion in street canyon and adjacent urban area
by Jiri Pospisil, Miroslav Jicha
Abstract: This paper presents an assessment of the influence of turbulence intensity in the close vicinity of a linear source of pollution on the consequent process of air pollutant dispersion in an urban environment. Turbulent flow structure in the vicinity of vehicles in motion significantly influences the dispersion of air pollution generated by road traffic into the environment of a traffic path. Higher turbulence intensity results in a greater mixing of air. The detailed investigation of cross-section vortex in the street canyon is done by a computational parametric study. Pollutant dispersion is monitored at a specific segment of an urban area crossed by a straight traffic path. The traffic path represents a studied linear source of pollution. The motion of vehicles along the traffic path has been considered as an input parameter for the consequent quantification of the kinetic energy of turbulence generation above the traffic path. The influence of generated kinetic energy of turbulence by linear road on the concentration of PM10 at receptor points located in the studied area is obtained by using the mathematical modelling method CFD. Assessment of the results gained defines a relation between the PM10 concentration at a ground-layer of air and the kinetic energy generated by a linear source.
Keywords: air pollution; modelling; kinetic energy of turbulence; PM10; dispersion; cars.
Application of a photochemical model for the assessment of regional air quality in southern Italy: procedures and results
by Annalisa Tanzarella, Ilenia Schipa, Angela Morabito, Camillo Silibello, Roberto Giua, Giorgio Assennato
Abstract: A modelling system based on FARM chemical transport model is applied to assess the air quality (AQ) over the Apulia region (Southern Italy) for 2013. The most relevant pollutant sources in the region are a steel plant, the largest in Europe (in the Taranto area), a coal-fired power plant, the second most powerful in Italy (in the Brindisi area) and biomass burning for residential heating. Simulation results evidence exceedances for PM10 daily limit value and benzo(a)pyrene annual limit values occurring in some areas. The evaluation of the model performance has been conducted by using the software DELTA Tool, developed within FAIRMODE to support the application of the EU Air Quality Directive. Results show good performance of the model, with a tendency to underestimate PM10 and ozone levels. These results suggest to use this modelling strategy for further source apportionment studies, in order to identify the sources that mainly affect air quality and to implement proper emission control strategies.
Keywords: air quality assessment; photochemical model; model evaluation tool.
Evaluation and development of tools to quantify the impacts of roadside vegetation barriers on near-road air quality
by Vlad Isakov, Akula Venkatram, Richard Baldauf, Parikshit Deshmukh, Max Zhang
Abstract: Traffic emissions are associated with the elevation of health risks of people living close to highways. Roadside vegetation barriers have the potential of reducing these risks by decreasing near-road air pollution concentrations. However, while we understand the mechanisms that determine the mitigation caused by solid barriers, we still have questions about how vegetative barriers affect dispersion. The US EPA conducted several field experiments to understand the effects of vegetation barriers on dispersion of pollutants near roadways (e.g. 2008 North Carolina study and 2014 California study) that indicate the reduction of near-road pollutant concentrations can be up to 30% due to the barrier effects. The results of these field studies are being used to develop and evaluate dispersion models that account for the effects of near-road vegetative barriers. These models can be used for evaluating the effectiveness of vegetation barriers as a potential mitigation strategy to reduce exposure to traffic-related pollutants and their associated adverse health effects. This paper presents the results of the analysis of the field studies and discusses dispersion models being used to describe the data in order to simulate the effects of near-road barriers and to develop recommendations for model improvements
Keywords: roadways; barriers; vegetation; dispersion; models.
Analysis of the internal boundary layer formation on tropical coastal regions using SODAR data in Rio de Janeiro, Brazil
by Leonardo Aragão, Silvana Di Sabatino, Luiz Claudio Pimentel, Fernando Duda
Abstract: This paper investigates local circulation features in the industrialised coastal region of Santa Cruz, Rio de Janeiro, Brazil, an area characterised by poor air quality. A better understanding of local circulation is expected to have an impact on the choice of suitable dispersion models and/or development of new ones to be used to plan mitigation strategies to reduce air pollution in the area. The topographic characteristics and the variety of atmospheric phenomena acting over the area suggest the formation of Internal Boundary Layers (IBLs) during cold front and bay breeze flows, whose parameterisation is often employed in air quality modelling. Preliminary results using data from acoustic atmospheric profilers show a frequent occurrence of IBL formation during bay breeze periods, coinciding with flow direction upstream of the major industries and having an impact on the most populated area of this region. Vertical profiles of main meteorological variables are evaluated, together with surface weather stations and satellite data, to derive a detailed physics-based description of the various stages of bay breeze in terms of the main forces, duration and atmospheric stabilities. It is found that the development phase of the sea breeze coincides with the largest bay/land differences and, consequently, it is the condition in which to observe the most pronounced IBL formation.
Keywords: sea breeze; acoustic soundings; SODAR; vertical profiles; internal boundary layer; tropical meteorology.
Model chain for buoyant plume dispersion
by Andrea Bisignano, Luca Mortarini, Enrico Ferrero, Stefano Alessandrini
Abstract: A new original software interface between the WRF mesoscale meteorological
model and the SPRAYWEB dispersion model has been developed. The model chain was
designed as a highly responsive tool for risk assessment and emergency-response purposes. The model interface reads the wind and temperature fields provided by WRF and interpolates them on a fixed-in-time grid, which is the input to the dispersion model. Furthermore, it calculates the turbulence-parameter vertical profiles, based on the surface-layer data provided by WRF. In this work, we simulate the dispersion of a high buoyancy plume. The model chain performances were tested against the Bull Run dataset.
Keywords: Lagrangian model; pollution dispersion; plume rise.
New power law inflow boundary conditions for street-scale modelling
by Vasilis Akylas, Fotios Barmpas, Nicolas Moussiopoulos, George Tsegas
Abstract: In street-scale numerical simulations using computational fluid dynamics models, normally the inlet flow should preserve the horizontal homogeneity upstream and downstream of the area where the resolved obstacles reside. Hence, the vertical profiles of the main atmospheric flow quantities must comply with the roughness characteristics of the ground surface. Horizontally homogenous boundary conditions do not normally agree with field measurements while at the same time the profiles obtained by measurements do not preserve the homogeneity of the flow. As a result, in recent years alternative sets of boundary conditions have been proposed in order to bridge the gap between real life vertical profiles of the atmospheric boundary layer and those applied as input boundary conditions for modelling purposes. In the present study the homogeneity of the boundary conditions is addressed by applying the power law for the mean wind speed to obtain the appropriate vertical profiles.
Keywords: atmospheric boundary layer; computational fluid dynamics; boundary conditions; microscale; power law; street scale modelling.
Validation of meteorological forecasts in fine spatial and temporal resolution produced as an input for dispersion models
by Primož Mlakar, Dragana Kokal, Boštjan Grašič, Marija Zlata Božnar, Dejan Gradišar, Juš Kocijan
Abstract: In conditions of complex terrain, modelling of air pollutant dispersion still has a number of scientific challenges. Ideally, appropriate meteorological data should be available for modelling. Unfortunately, for many purposes, there is no time to carry out suitable measuring campaigns. Therefore, the results of prognostic weather forecasts (NWP models) are being widely used. However, these models still have quite a few disadvantages when their results are used as input for dispersion models over complex terrain. This study presents the validation of the quality of the weather forecasts in the surroundings of the Nuclear Power Plant Krko in Slovenia, an area with highly complex terrain and the resulting complex meteorological characteristics. The forecast is available for a horizontal resolution of 2 km and half hour temporal interval and seven days in advance. The predicted meteorological parameters are validated using the measured meteorological parameters.
Keywords: validation; weather forecast; fine spatial and temporal resolution; complex terrain.
A review of dispersion modelling of agricultural and bioaerosol emissions with non-point sources
by Jenny Stocker, Andrew Ellis, Steve Smith, David Carruthers, Akula Venkatram, William Dale, Mark Attree
Abstract: This paper presents a review of pollutant dispersion modelling from non-point sources, focused on agricultural and bioaerosol sources. Relevant non-point source characteristics were collated from a literature review. These values were used to describe a typical agricultural source using line, area, volume and jet source types in the plume dispersion models ADMS and AERMOD; predicted downwind pollutant concentrations are compared. The modelling shows that predicted ground-level concentrations beyond approximately 100m downwind are similar for the majority of non-point source types. ADMS and AERMOD were used to represent releases from four sheds housing intensively farmed poultry as a case study. When the emission and volume flow rates used in the modelling were derived from measurements, the models give reasonably accurate predictions. However, for releases with non-negligible efflux, modelling using non-point sources allowing for the momentum and buoyancy of the release has much better agreement with observations than those that do not.
Keywords: dispersion; ammonia; odour; non-point sources; agriculture; poultry.
Time scale analysis of chemically reactive pollutants over urban roughness in the atmospheric boundary layer
by Zhangquan Wu, Chun Ho Liu
Abstract: Most practical dispersion models assume inert pollutants but air pollutants are often chemically reactive. There is thus a need for including pollution chemistry in plume dispersion models. In this study, turbulent dispersion of reactive pollutants in the neutral atmospheric boundary layer (ABL) over a hypothetical urban area in the form of an array of idealised street canyons is investigated using large-eddy simulation (LES). Nitric oxide (NO) is emitted from the first street canyon into the urban ABL, mixes with ozone (O3) and produces nitrogen dioxide (NO2) to model bimolecular chemical reaction. The time scales of NO oxidation and dispersion are compared in detail. It is found that they are coupled with each other and collectively modify the dispersion coefficient.
Keywords: air pollutant dispersion; large-eddy simulation; pollution physics and chemistry.
Pollutant removal mechanism in two-dimensional street canyons: a laboratory study
by Annalisa Di Bernardino, Paolo Monti, Leuzzi Giovanni, Giorgio Querzoli
Abstract: Velocity and concentration fields have been measured simultaneously in the water channel to quantify the turbulent dispersion of a passive tracer emitted at street level by a line source within an idealised urban canyon. The experiment has been conducted for an arrangement of two-dimensional obstacles with an aspect ratio of unity. Statistical moments of velocity and concentration have been calculated with high spatial resolution. Furthermore, the simultaneous measure of velocity and concentration at the same point made it possible to determine the tracer flux in the whole domain as well as to quantify the removal and re-entrainment of the pollutant through the canyon top.
Keywords: street canyon; concentration flux; concentration peaks; water channel; line source; building; urban canopy; skimming flow; image analysis; PLIF.
Definition of typical-day dispersion patterns as a consequence of a hazardous release
by Stefano Alessandrini, Francois Vandenberghe, Josh Hacker
Abstract: Self-organising maps (SOMs), a particular application of artificial neural networks, are used to extract a given number of typical days from a 30-year long record of 24-hour meteorology and concentration fields. SOMs represent a mechanism for defining complex relationships in multidimensional datasets. The proposed methodology provides information regarding the probability of a typical time evolution of the concentration patterns (typical days), which could be important for some applications when estimating a priori the impact of a potential release of toxic substances. We have run the Weather and Research Forecasting (WRF) model for a defined given month over a 30-year period with two nested grids to generate the required input for the Second-order Closure Integrated Puff diffusion model (SCIPUFF). The dispersion simulations are related to an instant point release at ground level and are carried out during the same period and in the spatial domain covered by the inner WRF grid. An array for each day, including the wind components, boundary layer height, and integrated concentration over 24 hours at all the grid points, is input to the SOM to perform an iterative learning process. The result is a number of typical days associated with different probabilities of occurrence. An assessment of the performance and reliability of this approach will be presented.
Keywords: self-organising maps; transport and dispersion models; neural network; air quality; risk assessment; Scipuff.
Community multi-scale air quality atmospheric dispersion model adaptation for Hungary
by Dóra Lázár, Tamás Weidinger
Abstract: In recent years it has become increasingly important to measure and predict the concentration of harmful atmospheric pollutants such as dust, aerosol particles, nitrogen compounds, and ozone. By adapting the community multi-scale air quality (CMAQ) model we have implemented a coupled air qualitymeteorological environmental model system, primarily for the representation of atmospheric ozone in Hungary. We used the WRF model in order to generate the meteorological driver database and the so-called SMOKE model for the construction of the input emission database. Our model system is separately run on three levels of a one-way nested grid with spacings of 108/36/12 km. We studied ozone forecasts based on different model settings and transition times, using several verification methods. This paper presents the outline of the project work, and the first results of concentration calculations are compared with national ambient air station data. Our results show that the night-time concentration of ozone is overestimated in our adapted model system.
Keywords: air-quality modelling; ozone; CMAQ; SMOKE; WRF; emission; model adaptation.
The air quality in narrow two-dimensional urban canyons with pitched and flat roof buildings
by Simone Ferrari, Maria Grazia Badas, Michela Garau, Giorgio Querzoli, Alessandro Seoni
Abstract: This paper deals with the air quality in narrow urban canyons. The first target is the investigation of the modifications that the roof shape induces in the flow and turbulence, through the comparison of velocity fields, turbulence characteristics and air exchanges with the outer flow in arrays of buildings with flat and pitched roofs. The second target is the assessment of the capability of a RANS model to correctly simulate the flow. The analysed quantities include velocity fields and profiles, turbulence characteristics fields and an integral parameter, the vertical air-exchange rate ACH, measuring the rate of air removal from a street canyon. Results show that the pitched roof strongly modifies the topology of the flow and increases the turbulence and the air exchange between the canyon and the external flow, so the choice of the roof shape can be meaningful for building design, planning strategies and regulatory purposes.
Keywords: narrow urban canyon; air quality; natural ventilation; pitched roof; RANS simulation; laboratory simulation.
Validation of Gaussian plume model AEROPOL against Cabauw field experiment
by Marko Kaasik, Gertie Geertsema, Rinus Scheele
Abstract: The Gaussian dispersion model AEROPOL is validated against the Cabauw (1977-1978) dataset, by applying the parameters and rules from the model validation kit. The purpose to revisit this experiment is preparation for fast response to buoyant accidental releases. In the AEROPOL model the classical Pasquill-Gifford stability and a scheme based on Lagrangian time scales are used as alternatives. Validation is based on correlation, fractional bias, fractional sigma, NMSE and fraction in factor 2, applying these statistics to maximal arc-wise, near-centreline and cross-wind integrated concentrations. Both parameterisations are found fairly adequate. The Gryning scheme results in too wide a Gaussian spread and thus in lower maxima compared to measurements, whereas the Pasquill parameterisation gives sharper maxima, which makes the statistics more sensitive to small discrepancies in plume position. The average wind between the lowest measurement level and release level is found to be a good approximation to represent the position of the Gaussian plume.
Keywords: Gaussian plume; dispersion experiment; Cabauw; AEROPOL; HARMONIE; model validation kit.
The use of a new diagram for the analysis of the daily cycles in the air-pollution data
by Marija Zlata Božnar, Boštjan Grašič, Primož Mlakar, Dejan Gradišar, Juš Kocijan
Abstract: From a temporal viewpoint, air pollution has significant daily patterns/cycles of behaviour. These cycles are conditioned by anthropogenic and natural phenomena. In both cases, a detailed observation and an understanding of the daily cycles rules or daily patterns of air pollution can be significant and at the same time can contribute to more effective measures to reduce the harmful impact of air pollution on human health. In this paper, the new sunflower diagram is presented. The key advantage of the sunflower diagram is the ease of understanding the result and the ability to present information in the form of a graphic pattern, allowing the user to quickly understand the content. Using the sunflower diagram, we will present an analysis of the meteorological parameters that are important for understanding air pollution and air-pollution data for different locations in Slovenia.
Keywords: daily cycles; analysis tool; sunflower diagram; air-pollution flower; weather flower; wind flower.
Effect of the long-range transport on the air quality of the Greater Budapest area
by Zita Ferenczi, Laszlo Bozo
Abstract: SO2, NO2 and Particulate Matter (PM) are air pollutants, generated by a variety of human activities and can travel long distances in the atmosphere and cause a wide range of air quality problems in Europe. For some cities the influence of transboundary and national contributions in PM concentrations are dominant, and only a little improvement can be expected from local control policies. The air quality of Budapest is determined mainly by the local residential heating and traffic emissions combined with the meteorological conditions. Sometimes the impact of the transboundary sources can be negligible, especially under special meteorological conditions when the local effects determine the air quality of Budapest, but sometimes it could be responsible for the formation of air pollution episodes. In this research the effect of long-range transport on the air quality of Budapest was analysed in detail, using the outputs of EMEP chemical transport model.
Keywords: long-range transport; EMEP chemical transport model; urban air quality; emission.
Special Issue on: HARMO17
Application of inverse dispersion modelling for the determination of PM emission factors from fugitive dust sources in open-pit lignite mines
by Athanasios Triantafyllou, Nicolas Moussiopoulos, Athina Krestou, George Tsegas, Fotios Barmpas, Stelios Garas, Μelina Andreadou
Abstract: The operation of large open-pit lignite mines represents a significant source of fugitive dust emissions connected to energy production. Emission inventories can be used to provide operational estimates of the total dust burden in the surrounding areas attributable to mining operations. In this work, a methodology based on the inverse dispersion modelling approach, combining two different dispersion models, is used for preparing a dust emissions inventory for several activity types in the lignite mines of Western Macedonia, Greece. A 3-year campaign of field measurement experiments provides the necessary meteorological data and upwind-downwind concentration levels in the area of each activity. A comparison of calculated emission rates provided by the two dispersion models indicates a very good agreement, while the normalised downwind concentration timeseries are accurately reproduced. Emission factors are calculated for each experiment and per-activity, leading to the formulation of empirical relations for the total fugitive dust emissions.
Keywords: inverse dispersion modelling; fugitive dust sources; emission factors; open pit mines.