Evaluation of a model for hourly spatial concentration distributions

Grønskei, Knut Erik; Walker, Sam; Gram, Frederick

doi:10.1016/0957-1272(93)90050-g

Cited by 16 publications

(5 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…29,30 Combination of the Eulerian grid model and the Gaussian subgrid models enables a more detailed description of the concentration levels close to individual sources. The model was implemented on a 22 km ϫ 18 km domain covering the Oslo metropolitan area, with a grid spacing of 1 km ϫ 1 km.…”

Section: Modeling the Pm 10 Contribution Frommentioning

confidence: 99%

Quantification of Monosaccharide Anhydrides by Liquid Chromatography Combined with Mass Spectrometry: Application to Aerosol Samples from an Urban and a Suburban Site Influenced by Small-Scale Wood Burning

Yttri

Dye

Slørdal

et al. 2005

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

Levels of the monosaccharide anhydride (MA) levoglucosan and its isomeric compounds galactosan and mannosan were quantified in the PM10 fraction (particulate matter < or = 10 microm in aerodynamic diameter) of ambient aerosols from an urban (Oslo) and a suburban (Elverum) site in Norway, both influenced by small-scale wood burning. MAs are degradation products of cellulose and hemicellulose, and levoglucosan is especially emitted in high concentrations during pyrolysis and combustion of wood, making it a potential tracer of primary particles emitted from biomass burning. MAs were quantified using a novel high-performance liquid chromatography/ high-resolution mass spectrometry-time of flight method. This approach distinguishes between the isomeric compounds of MAs and benefits from the limited sample preparation required before analysis, and no extensive derivatization step is needed. The highest concentrations of levogucosan, galactosan, and mannosan (sigmaMA) were recorded in winter because of wood burning for residential heating (sigmaMA(MAX) = 1,240 ng m(-3)). This finding was substantiated by a relatively high correlation (R2 = 0.64) between the levoglucosan concentration and decreasing ambient temperature. At the suburban site, sigmaMA accounted for 3.1% of PM10, whereas the corresponding level at the urban site was 0.6%. The mass size distribution of MAs associated with atmospheric aerosols was measured using a Berner cascade impactor. The size distribution was characterized with a single mode at 561 nm. Ninety-five percent of the mass concentration of the MAs was found to be associated with particles < 2 micro.m. A preliminary attempt to estimate the contribution of wood burning to the mass concentration of PM10 in Oslo using levoglucosan as a tracer indicates that 24% comes from wood burning. This is approximately a factor of 2 lower than estimated by the AirQUIS dispersion model.

show abstract

Section: Modeling the Pm 10 Contribution Frommentioning

confidence: 99%

Quantification of Monosaccharide Anhydrides by Liquid Chromatography Combined with Mass Spectrometry: Application to Aerosol Samples from an Urban and a Suburban Site Influenced by Small-Scale Wood Burning

Yttri

Dye

Slørdal

et al. 2005

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

show abstract

“…The spatial distribution of concentrations served as a basis different microenvironments. 1 for estimating each individual's exposure. An exposure assess-Grenland, the study area, is a heavily industrialised area in ment model estimates exposure for each compound, for each southern Norway.…”

Section: Methodsmentioning

confidence: 99%

Air pollution exposure monitoring and estimation

Clench‐Aas

Bartoňová²,

Grønskei³

et al. 1999

J. Environ. Monitor.

View full text Add to dashboard Cite

This paper presents methodology and results of a dynamic individual air pollution exposure model (DINEX) that calculates the hourly exposure for each adult in a panel study. Each of over 260 participants, through the use of a diary, provided information used in the model to calculate his/her personal, individualised exposure. The participants filled out the diary daily, hour by hour, over two, two month periods. The exposure assessment model coupled the diary information and results of an indoor/outdoor measurement program, with the results of dispersion modelling on an hourly basis for an industrial area in Norway. The estimated air pollution concentrations from the dispersion model, based on continuous meteorological measurements, were calibrated with air pollutant concentrations measured continuously.

show abstract

“…1 illustrates the different model elements and input data to be considered. A formal description of the calculation procedure is given by Grùnskei et al 6 In Fig. 1, model elements are marked by capital letters A±F.…”

Section: Model Elementsmentioning

confidence: 99%

“…The modelling was based on existing models for different chemical species. 6 The models have been evaluated for several components in different areas. 7,8 The aim of dispersion modelling, from the point of view of health studies, is to provide estimates of personal exposure to outdoor air for the participants.…”

Section: Introductionmentioning

confidence: 99%

Air pollution exposure monitoring and estimation VII. Estimation of population exposure in a central European airshed

Grønskei

Bartoňová

Brechler

et al. 2000

J. Environ. Monitor.

View full text Add to dashboard Cite

In order to clarify the local variation in exposure and source-receptor relationships, a dispersion model for estimating air pollution concentrations was developed for a polluted area in the Czech Republic. Three models characterized by different spatial resolution were integrated into one modelling tool. A regional-scale dispersion model accounted for pollution contribution from sources outside the modelling area. Local- and urban-scale dispersion models were used to calculate local concentration distributions. Calculated concentration distributions were evaluated. Deviations between observed and calculated concentrations were not correlated in space, except in episodes, and concentrations measured at spatially representative stations were assimilated into the model results using statistical interpolation (simple kriging). The results indicated that centralized heating plants and local home heating were the most important sources for sulfur dioxide (SO2) pollution. Both high and low level sources may contribute to the accumulation of pollution concentrations in episodes. The measured concentrations were important for the description of distributions in episodes characterized by complex wind and dispersion conditions. The applicability of source oriented model calculations to correctly represent measured concentrations in the pollution episodes was limited due to the fact that meteorological conditions representative of high concentration episodes were characterized by very low wind speed and variable wind directions. About 8,000 individuals were given an exposure estimate representing contribution from local emissions, based on the estimated hourly outdoor exposure to SO2 at their home/work addresses in the 3 month study period in the autumn of 1991. The results showed that, for 5% of participants, the maximum hourly contribution of local emissions was over 380 microg m(-3). For the 3 month average, both large-scale and local-scale pollution contribute significantly. For primary compounds, such as SO2, steep gradients are observed in the vicinity of strong local sources. These gradients are important for exposure characteristics and health effect quantification, and often will not be captured by an existing monitoring network. The calculations can be extended to other periods or to different compounds.

show abstract

Evaluation of a model for hourly spatial concentration distributions

Cited by 16 publications

References 7 publications

Quantification of Monosaccharide Anhydrides by Liquid Chromatography Combined with Mass Spectrometry: Application to Aerosol Samples from an Urban and a Suburban Site Influenced by Small-Scale Wood Burning

Quantification of Monosaccharide Anhydrides by Liquid Chromatography Combined with Mass Spectrometry: Application to Aerosol Samples from an Urban and a Suburban Site Influenced by Small-Scale Wood Burning

Air pollution exposure monitoring and estimation

Air pollution exposure monitoring and estimation VII. Estimation of population exposure in a central European airshed

Contact Info

Product

Resources

About