air quality dispersion Articles | Environmental XPRT

Dispersion modelling: a tool for local air quality management

A local air quality management system, and the use of dispersion modelling as a tool for the system, are described. The Turkish town of Gehze is used as a model.Keywords: air pollution, air quality management, dispersion modelling, ...

Oct. 29, 2004

By Inderscience Publishers

Canarina DISPER Software · indoor air quality dispersion · algorithms 8

Canarina DISPER Software · indoor air quality dispersion 9.1.3 Wind Speed Profile The wind power law is used to adjust the observed wind speed, uref, from a reference measurement height, zref, to the stack or release height, hs. The stack height wind speed, us, is used in the Gaussian plume equation. The power law equation is of the form: us=uref(hs/zref)p (4) where p ...

Nov. 13, 2011

By Canarina Environmental Software

Procedures used by the United States Environmental Protection Agency (US-EPA) to develop and adopt newer dispersion models

This paper summarises the management and procedural issues that led to the successful development of AERMOD and CALPUFF and how they will come to be approved regulatory models by the US-EPA in the next few months. The legal requirements for constantly updating models is contained in the 1977 Clean Air Act that requires the US-EPA to publish a "Modelling Guideline" and to hold a hearing ...

Jan. 26, 2004

By Inderscience Publishers

Air quality assessment in Bologna by an urban dispersion model

An urban dispersion model (ADMS?Urban) was run to calculate PM10 and NO2 concentration during a one-year period, on a district of Bologna, Italy. Moreover, the exposure of 333 children was estimated using model outputs corrected with observations. The model was able to correctly simulate the long-term statistical properties of roadside observed concentrations (such as annual mean and frequency ...

Jun. 29, 2009

By Inderscience Publishers

Canarina DISPER Software · air quality dispersion model · algorithms 3

Canarina DISPER Software · air quality dispersion model Symbol / Definition Ly= Initial plume length for Schulman-Scire downwash sources with enhanced lateral plume spread (m) Lb= Lesser of the building height and crosswind projected building width (m) _= Alongwind length of open pit source (m) P(x,y)= Profile adjustment factor (dimensionless) p= Wind speed power law profile ...

Nov. 12, 2011

By Canarina Environmental Software

An investigation of the urban heat island of Rome through a canyon–based subgrid scheme

This paper describes some modifications to a mesoscale model surface scheme to better account for urban heat–storage. The approach involves integrating the Subgrid Town Energy Budget (STEB) with the Regional Atmospheric Modelling System (RAMS). The integrated system has been applied to the investigation of the Urban Heat Island (UHI) of Rome, Italy, and the surrounding area (Lazio Region), ...

Jun. 18, 2012

By Inderscience Publishers

Air dispersion modelling for individual exposure studies

The concentration fluctuations of a dispersing hazardous gaseous pollutant in the atmospheric boundary layer, and the hazard associated with short–term concentration levels, demonstrate the necessity of estimating the magnitude of these fluctuations using predicting models. To predict and estimate the maximum expected dosage and the exposure time within which the dosage exceeds certain health ...

Jun. 18, 2012

By Inderscience Publishers

Effect of roughness inhomogeneities on the development of the urban boundary layer

Wind tunnel measurements over a regular array of cubes were carried out to investigate the influence of surface inhomogeneities on the development of the urban boundary layer. Two idealised cases were investigated. The first one was in terms of a strong step change in roughness from very smooth to very rough with a low turbulent approach flow and a thin approach boundary layer. For this case it ...

Sep. 1, 2005

By Inderscience Publishers

Evaluation of AirGIS: a GIS–based air pollution and human exposure modelling system

This study describes in brief the latest extensions of the Danish Geographic Information System (GIS)–based air pollution and human exposure modelling system (AirGIS), which has been developed in Denmark since 2001 and gives results of an evaluation with measured air pollution data. The system shows, in general, a good performance for both long–term averages (annual and monthly averages), ...

Jun. 18, 2012

By Inderscience Publishers

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 ...

Oct. 31, 2011

By Inderscience Publishers

Study of natural and traffic–producing turbulences analysing full–scale data from four street canyons

Parameters related with natural and traffic producing turbulences are estimated for four street canyons considering all wind directions. Available data include air pollution concentrations measured in Göttinger Strasse (Hannover, Germany), Schildhornstrasse (Berlin, Germany), Jagtvej (Copenhagen, Denmark) and Hornsgatan (Stockholm, Sweden), background pollution, wind speed and direction measured ...

Jun. 18, 2012

By Inderscience Publishers

The sustainable development of Heathrow Airport: model inter-comparison study

Air quality modelling near airports has received attention due to the impact of emissions from aircrafts near ground level. This work is part of the model inter-comparison study undertaken for the Department of Transport in connection with air quality near Heathrow Airport. Results formed part of a submission to the UK government in July 2006. The Emissions and Dispersion Modelling System (EDMS) ...

Feb. 8, 2011

By Inderscience Publishers

Experimental study of turbulence and vertical temperature profile in the urban boundary layer

We observed the turbulence and vertical profile of temperature in and above the roughness sublayer (RS) using a tower, a tethered balloon and a Doppler sodar in Himeji City. A 3–D ultrasonic anemometer–thermometer was sited at a height of 54 m on the tower. The present results showed that in the RS, the ratio of friction velocity to wind speed, u* /u, observed under unstable conditions of −4.2 ...

Jun. 18, 2012

By Inderscience Publishers

New Nitrogen Dioxide Ambient Air Quality Standard Could Pose Challenges

In the more than 200 air quality modeling analyses that ALL4 meteorologists have conducted, demonstrating compliance with the annual nitrogen dioxide (NO2) National Ambient Air Quality Standard (NAAQS) of 53 parts per billion (ppbv) has rarely been an issue. The relative ease for demonstrating compliance with the annual NO2 NAAQS is due to two (2) factors. First, the NAAQS for NO2 is an annual ...

Feb. 15, 2010

By All4 Inc.

A congestion sensitive approach to modelling road networks for air quality management

This research establishes an approach to modelling a congested road network for air quality management, which enables the assessment of traffic management solutions that may create only subtle changes in the traffic flow regimes. Road network emissions have been calculated using standard factors taking into account details of vehicle fleet composition, average speeds and road type. Additionally, ...

Oct. 16, 2014

By Inderscience Publishers

Exploring the properties of local and non–local vertical diffusion schemes in the EMEP model using 222Rn data

The simulations of hourly 222Rn concentrations are performed with the EMEP model to validate different parameterization schemes for vertical mixing. In addition to recently evaluated non–local vertical diffusion schemes, a new scheme which is a local and based on total turbulent energy (TTE) has been implemented in the model and evaluated. Due to its properties 222Rn is commonly used to ...

Oct. 13, 2012

By Inderscience Publishers

Diurnal variation of the mixing-layer height and polonium concentration in the air

The Mixing Height (MH) is one of the most important parameters that characterise the range of the atmospheric turbulence. This parameter shows characteristic diurnal variation but cannot be measured immediately. Therefore, it is evaluated indirectly by measuring other quantities. The measurement of radon concentration in the atmospheric air is one of the methods using natural occurring ...

Sep. 1, 2005

By Inderscience Publishers

Application of Lagrangian particle dispersion models to air quality assessment in the Trans-Manche region of Nord-Pas-de-Calais (France) and Kent (Great Britain)

In the framework of the cross-border EU INTERREG IIIA activity, the joint Anglo-French project, ATTMA, has been commissioned to study Aerosol Transport in the atmosphere of the Cross-Channel, or 'Trans-Manche' region of Nord-Pas-de-Calais (France) and Kent (Great Britain). The air quality of the region is dominated by the industrial area of Dunkerque, in addition to transportation sources linked ...

Jan. 12, 2010

By Inderscience Publishers

Computational modelling of airflow in urban street canyon and comparison with measurements

The main goal of this study was to predict the airflow in a street canyon surrounded by an urban area using CFD modelling. In the street geometry described in the main part, the actual airflow directly influences air infiltration into buildings. Different models of turbulence were tested as well as specific wind boundary conditions. A correct assignment of boundary conditions (i.e., mainly wind ...

Sep. 1, 2005

By Inderscience Publishers

Evaluation of turbulence from traffic using experimental data obtained in a street canyon

The present study analyses the influence of traffic-produced turbulence (TPT) on CO concentration using full-scale measurements obtained in Gottinger Strasse (Hannover, Germany). Cases with airflow within ±11.25° from the direction perpendicular to the street axis were used. The values C = Ci–Cb (Ci is concentration measured inside the street canyon and Cb is the background concentration) were ...

Sep. 1, 2005

By Inderscience Publishers