atmospheric dispersion Articles

  • On the dispersion models and atmospheric dispersion

    As an air pollutant is transported, the pollutant disperses into the surrounding air so that it arrives at a lower concentration than it was on leaving the source. Strict environmental regulations worldwide resulted in a growing concern about the validity of air quality dispersion models. The present work is a try to evaluate the applicability of some dispersion models on the emission from an ...


    By Inderscience Publishers

  • Evaluation of new generation atmospheric dispersion models

    The paper considers the regulatory view of evaluating dispersion models. There is no proscription for regulatory studies in the UK, so differences between dispersion calculations from different models and versions of models are then as important as their absolute veracity. An example shows variations in calculated concentration due to variations between two different versions of a model and two ...


    By Inderscience Publishers

  • Evaluation of statistical models in atmospheric dispersion modelling

    When a gas is released into the atmosphere, there are inevitably random fluctuations in its concentration due to turbulence. Great recent improvements in instrumentation have shown how large these are. This has been acknowledged by CEC (the Commission of the European Communities), for example in that part of its Environment and Climate Programme (Framework IV) dealing with accidents. Likewise, ...


    By Inderscience Publishers

  • A review of evaluation procedures for atmospheric dispersion models

    Evaluation of atmospheric dispersion models is vital to justify their use within the air quality component of environmental assessments. The Model Validation Kit, compiled and distributed by Helge Olesen of NERI, is often used for such evaluations. Whilst the Model Validation Kit has a wide range of functionality, its users often limit their evaluation to a few simplistic calculations. ...


    By Inderscience Publishers

  • Uncertainty adjustments to deterministic atmospheric dispersion models

    Atmospheric Dispersion Models (ADMs) are routinely used in environmental impact assessment, risk analysis, and source apportionment studies. There are a variety of such computational ADMs, but these models usually only provide deterministic predictions or estimation of uncertainty. By introducing error components in ADMs, we formulate statistical modelling to obtain more precise prediction. These ...


    By Inderscience Publishers

  • Modelling of atmospheric pollutant dispersion in coastal areas

    Some characteristics of air pollution in Tarragona (Spain) were investigated. Tarragona has an important petrochemical industry in a coastal region with a complex terrain. The study was made numerically in sea breeze conditions with a three-dimensional mesoscale meteorological model. The temporal and spatial variations of the wind fields have been used in the Lagrangian equation for a ...


    By Inderscience Publishers

  • Validation of atmospheric dispersion models using ETEX data

    Two models frequently used to simulate the dispersion of pollutants in the atmosphere have been compared. This is necessary because only a well-tested and well-calibrated simulation model can be a good representation of the reality of the dispersion of pollutants. The models evaluated (HYSPLIT_4 with its four variants and MEDIA) were run using as input parameters the same meteorological dataset ...


    By Inderscience Publishers

  • A model for simulating atmospheric dispersion in low-wind conditions

    A practical model for low-wind conditions was derived by integration of an instantaneous three-dimensional Gaussian puff equation, in which wind speed was assumed to be zero and standard deviations of a smoke (σy and σz) were expressed as a linear function of the dispersion time. When the plume spreads σy and σz were ...


    By Inderscience Publishers

  • Atmospheric dispersion methods in environmental impact assessment in Flanders

    This paper presents a survey of the experiences in Flanders during the first five years of implementing environmental impact assessment (EIA) as specified by the European Directive 85/337/EEC and the Flemish Orders of 23 March 1989. The current EIA procedure is presented in general, and an indication is given of the number of impact assessments carried out to date. A typical methodology ...


    By Inderscience Publishers

  • Modelling of atmospheric flow and dispersion in the wake of a cylindrical obstacle

    The computational fluid dynamics code ADREA–HF is used to simulate atmospheric dispersion field experiments around an isolated cylindrical obstacle and two upwind sources of ammonia and propane, with the ammonia source located at different lateral positions. Model calculated concentrations and concentration fluctuations are compared with the experimental results, to investigate the effect of the ...


    By Inderscience Publishers

  • Atmospheric dispersion modelling for regulatory purposes in the United Kingdom

    Short-range atmospheric dispersion models are used to assess the environmental impact of airborne pollutants from industrial plants. The results are of interest to a range of specialist and non-specialist groups, including regulators, operators, environmental organisations, and local residents. In order that these groups can be well-informed, it is important to develop clear and consistent ...


    By Inderscience Publishers

  • Simulations of atmospheric dispersion in an urban stable boundary layer

    The results of numerical simulations of tracer dispersion in an urban stable boundary layer are presented. Both Gaussian approximation and fourth order closure are considered and a Gram-Charlier probability density function is used in our Lagrangian stochastic model. Different parameterisations for the boundary-layer height and different values of kurtosis are tested. The model is based on the ...


    By Inderscience Publishers

  • Atmospheric dispersion of pollutants in Sado estuary (Portugal) using biomonitors

    Epiphytic lichen transplants and aerosol samplers were put together in the Setubal area, Portugal. They were analysed by Instrumental Neutron Activation Analysis (INAA) and Proton Induced X-ray Emission (PIXE). The lichen dataset pointed out nine factors. No relevant differentiation was found towards different positioning of the lichens. T-transplants were delayed towards F-transplants, and for ...


    By Inderscience Publishers

  • Regulatory atmospheric short and medium range dispersion models in Italy

    Since the (partial) acceptance in Italy of the EU Directive 85/337/EEC concerning environmental impact assessment procedures, there has been a rapid growth in the use of atmospheric dispersion simulation tools, which are also being used in air-quality management plans. This paper describes the state of the art in the development and application in Italy of the short and medium range ...


    By Inderscience Publishers

  • Statistical evaluation of centreline concentration estimates by atmospheric dispersion models

    Within the American Society for Testing and Materials (ASTM), a standard practice (Z6849Z1) is being developed to provide an objective statistical procedure for comparing air quality simulation modelling results with tracer field data. The practice is limited to steady state, local-scale transport from isolated point sources in simple terrain. Evaluation data having similar external conditions ...


    By Inderscience Publishers

  • Evaluation of atmospheric particle dispersion at a contaminated mine using biomonitors

    This study has carried out the assessment of magnitude of toxic elements contamination in and around the Sao Domingos mining area, a copper-sulphide open pit mine, and atmospheric transport of above elements by using lichens and Instrumental Neutron Activation Analysis (INAA). Samples of the epiphytic lichen Evernia prunastri and soils were collected. The concentrations of As, Sb, Fe and Zn were ...


    By Inderscience Publishers

  • A Test Reference Year (TRY) approach to gas dispersion in the atmosphere

    For environmental analysis such as the dispersion of pollutants in the atmosphere, it is essential to have meteorological data that are relevant for a long period. In this paper, we explore the possibility of using an environmental Test Reference Year (TRY), i.e., a set of real, contemporaneous and hourly meteorological variables, 'extracted' from a hourly series of at least 10 years, for ...


    By Inderscience Publishers

  • Turbulence closure in atmospheric circulation model and its influence on the dispersion

    In this work the comparisons between measured and numerically simulated tracer experiments are presented for two different datasets. Different versions of the model system RMS, including the Regional Atmospheric Modelling System (RAMS) and the dispersion model SPRAY, accounting for alternative turbulence closures are used. These last are the Mellor and Yamada model level 2.5 and two versions of ...


    By Inderscience Publishers

  • Canarina DISPER Software · atmospheric dispersion model · algorithms 6

      Canarina DISPER Software · atmospheric dispersion model   9.1 Point source emissions   The model uses a steady-state Gaussian plume equation to model emissions from point sources, such as stacks.   9.1.1 ...

  • Comparison between analytical models to simulate pollutant dispersion in the atmosphere

    We present a numerical and statistical comparison between ADMM and GILTT approaches to simulate pollutant dispersion in the Planetary Boundary Layer (PBL). The numerical and statistical comparison of the ADMM and GILTT results confirms the equivalence of these methods. However, the ADMM approach is more efficient under computational point of view regarding the issue of computational time and, ...


    By Inderscience Publishers

Need help finding the right suppliers? Try XPRT Sourcing. Let the XPRTs do the work for you