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Journal articles on the topic 'Eulerian pollution model'

Author: Grafiati

Published: 4 June 2021

Last updated: 10 February 2022

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1

Zlatev, Z., J. Christensen, and �. Hov. "A Eulerian air pollution model for Europe with nonlinear chemistry." Journal of Atmospheric Chemistry 15, no. 1 (July 1992): 1–37. http://dx.doi.org/10.1007/bf00053607.

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2

Kumar, Sudarshan. "An Eulerian model for scavenging of pollutants by raindrops." Atmospheric Environment (1967) 19, no. 5 (January 1985): 769–78. http://dx.doi.org/10.1016/0004-6981(85)90065-4.

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3

Dimov, I., R. Georgieva, and Tz Ostromsky. "Monte Carlo sensitivity analysis of an Eulerian large-scale air pollution model." Reliability Engineering & System Safety 107 (November 2012): 23–28. http://dx.doi.org/10.1016/j.ress.2011.06.007.

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4

Christensen, Jesper Heile. "The Danish eulerian hemispheric model — a three-dimensional air pollution model used for the arctic." Atmospheric Environment 31, no. 24 (December 1997): 4169–91. http://dx.doi.org/10.1016/s1352-2310(97)00264-1.

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5

Atanassov, Dimiter. "Validation of the Eulerian pollution transport model PolTran on the Kincaid data set." International Journal of Environment and Pollution 20, no. 1/2/3/4/5/6 (2003): 105. http://dx.doi.org/10.1504/ijep.2003.004255.

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6

Higuera, F. J. "Eulerian model of a dilute spray of charged droplets." Journal of Aerosol Science 48 (June 2012): 34–45. http://dx.doi.org/10.1016/j.jaerosci.2012.01.008.

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7

Ismail, Tamer M., Eliseu Monteiro, Ana Ramos, M. Abd El-Salam, and Abel Rouboa. "An Eulerian model for forest residues gasification in a plasma gasifier." Energy 182 (September 2019): 1069–83. http://dx.doi.org/10.1016/j.energy.2019.06.070.

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Maldaner, Silvana, Michel Stefanello, Luis Gustavo N. Martins, Gervásio Annes Degrazia, Umberto Rizza, Débora Regina Roberti, Franciano S. Puhales, and Otávio C. Acevedo. "A quasi-experimental coastal region eddy diffusivity applied in the APUGRID model." Annales Geophysicae 38, no. 3 (May 4, 2020): 603–10. http://dx.doi.org/10.5194/angeo-38-603-2020.

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Abstract. In this study, Taylor statistical diffusion theory and sonic anemometer measurements collected at 11 levels on a 140 m high tower located in a coastal region in southeastern Brazil have been employed to obtain quasi-empirical convective eddy diffusivity parameterizations in a planetary boundary layer (PBL). The derived algebraic formulations expressing the eddy diffusivities were introduced into an Eulerian dispersion model and validated with Copenhagen tracer experiments. The employed Eulerian model is based on the numerical solution of the diffusion–advection equation by the fractional step/locally one-dimensional (LOD) methods. Moreover, the semi-Lagrangian cubic-spline technique and Crank–Nicolson implicit scheme are considered to solve the advection and diffusive terms. The numerical simulation results indicate that the new approach, based on these quasi-experimental eddy diffusivities, is able to reproduce the Copenhagen concentration data. Therefore, the new turbulent dispersion parameterization can be applied in air pollution models.

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Pouyaei, Arman, Yunsoo Choi, Jia Jung, Bavand Sadeghi, and Chul Han Song. "Concentration Trajectory Route of Air pollution with an Integrated Lagrangian model (C-TRAIL Model v1.0) derived from the Community Multiscale Air Quality Model (CMAQ Model v5.2)." Geoscientific Model Development 13, no. 8 (August 5, 2020): 3489–505. http://dx.doi.org/10.5194/gmd-13-3489-2020.

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Abstract. This paper introduces a novel Lagrangian model (Concentration Trajectory Route of Air pollution with an Integrated Lagrangian model, C-TRAIL version 1.0) output from a Eulerian air quality model for validating the source–receptor direct link by following polluted air masses. To investigate the concentrations and trajectories of air masses simultaneously, we implement the trajectory-grid (TG) Lagrangian advection scheme in the CMAQ (Community Multiscale Air Quality) Eulerian model version 5.2. The TG algorithm follows the concentrations of representative air “packets” of species along trajectories determined by the wind field. The diagnostic output from C-TRAIL accurately identifies the origins of pollutants. For validation, we analyze the results of C-TRAIL during the KORUS-AQ campaign over South Korea. Initially, we implement C-TRAIL in a simulation of CO concentrations with an emphasis on the long- and short-range transport effects. The output from C-TRAIL reveals that local trajectories were responsible for CO concentrations over Seoul during the stagnant period (17–22 May 2016) and during the extreme pollution period (25–28 May 2016), highly polluted air masses from China were distinguished as sources of CO transported to the Seoul Metropolitan Area (SMA). We conclude that during the study period, long-range transport played a crucial role in high CO concentrations over the receptor area. Furthermore, for May 2016, we find that the potential sources of CO over the SMA were the result of either local transport or long-range transport from the Shandong Peninsula and, in some cases, from regions north of the SMA. By identifying the trajectories of CO concentrations, one can use the results from C-TRAIL to directly link strong potential sources of pollutants to a receptor in specific regions during various time frames.

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Tou, S. K. W., and C. Y. Liu. "Lagrangian transport of suspended pollutants in Johor Strait by a finite element eulerian model." Journal of Environmental Science and Health . Part A: Environmental Science and Engineering and Toxicology 27, no. 6 (August 1992): 1371–88. http://dx.doi.org/10.1080/10934529209375801.

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11

Chen, Fangzhi, and Alvin CK Lai. "An Eulerian model for particle deposition under electrostatic and turbulent conditions." Journal of Aerosol Science 35, no. 1 (January 2004): 47–62. http://dx.doi.org/10.1016/s0021-8502(03)00383-5.

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12

Tessum, C. W., J. D. Hill, and J. D. Marshall. "InMAP: a new model for air pollution interventions." Geoscientific Model Development Discussions 8, no. 10 (October 29, 2015): 9281–321. http://dx.doi.org/10.5194/gmdd-8-9281-2015.

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Abstract. Mechanistic air pollution models are essential tools in air quality management. Widespread use of such models is hindered, however, by the extensive expertise or computational resources needed to run most models. Here, we present InMAP (Intervention Model for Air Pollution), which offers an alternative to comprehensive air quality models for estimating the air pollution health impacts of emission reductions and other potential interventions. InMAP estimates annual-average changes in primary and secondary fine particle (PM2.5) concentrations – the air pollution outcome generally causing the largest monetized health damages – attributable to annual changes in precursor emissions. InMAP leverages pre-processed physical and chemical information from the output of a state-of-the-science chemical transport model (WRF-Chem) within an Eulerian modeling framework, to perform simulations that are several orders of magnitude less computationally intensive than comprehensive model simulations. InMAP uses a variable resolution grid that focuses on human exposures by employing higher spatial resolution in urban areas and lower spatial resolution in rural and remote locations and in the upper atmosphere; and by directly calculating steady-state, annual average concentrations. In comparisons run here, InMAP recreates WRF-Chem predictions of changes in total PM2.5 concentrations with population-weighted mean fractional error (MFE) and bias (MFB) < 10 % and population-weighted R2 ~ 0.99. Among individual PM2.5 species, the best predictive performance is for primary PM2.5 (MFE: 16 %; MFB: 13 %) and the worst predictive performance is for particulate nitrate (MFE: 119 %; MFB: 106 %). Potential uses of InMAP include studying exposure, health, and environmental justice impacts of potential shifts in emissions for annual-average PM2.5. Features planned for future model releases include a larger spatial domain, more temporal information, and the ability to predict ground-level ozone (O3) concentrations. The InMAP model source code and input data are freely available online.

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Siour, G., A. Colette, L. Menut, B. Bessagnet, I. Coll, and F. Meleux. "Bridging the scales in a eulerian air quality model to assess megacity export of pollution." Environmental Modelling & Software 46 (August 2013): 271–82. http://dx.doi.org/10.1016/j.envsoft.2013.04.001.

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14

Mpimpas, H., P. Anagnostopoulos, and J. Ganoulis. "Uncertainty of model parameters in stream pollution using fuzzy arithmetic." Journal of Hydroinformatics 10, no. 3 (May 1, 2008): 189–200. http://dx.doi.org/10.2166/hydro.2008.037.

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Fuzzy arithmetic is employed for the analysis of uncertainties in water-stream pollution, when the various model parameters involved are imprecise. The one-dimensional advection–dispersion equation, for both a conservative and a non-conservative substance, was solved analytically for point and Gaussian-hill input loads of pollution, considering the dispersion and decay coefficients involved as fuzzy numbers. The solution of the advection–dispersion equation was also conducted numerically for the same input loads with the finite-difference method, employing a Lagrangian–Eulerian scheme. The good agreement between analytical and numerical results presented in the form of fuzzy numbers confirms the reliability of the numerical scheme. The advection–dispersion equation of a non-conservative substance was then solved numerically for ten different water quality parameters, in order to study the water pollution in a water stream. The dispersion coefficient, the source terms and the input loads were expressed as fuzzy numbers, and the concentration of each quality parameter was obtained in fuzzy-number form. With fuzzy modeling, imprecise data can be represented and imprecise output produced, with minimal input data requirements and without the need of a large number of computations.

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15

Shim, Shang-Gyoo, Seog-Yeon Cho, Gregory R. Carmichael, and Toshihiro Kitada. "The sensitivity of a 3-dimensional Eulerian model to uncertainties in emissions and dry deposition velocities." Atmospheric Environment (1967) 20, no. 10 (January 1986): 1979–87. http://dx.doi.org/10.1016/0004-6981(86)90339-2.

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16

Wind, Peter, Bruce Rolstad Denby, and Michael Gauss. "Local fractions – a method for the calculation of local source contributions to air pollution, illustrated by examples using the EMEP MSC-W model (rv4_33)." Geoscientific Model Development 13, no. 3 (March 30, 2020): 1623–34. http://dx.doi.org/10.5194/gmd-13-1623-2020.

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Abstract. We present a computationally inexpensive method for individually quantifying the contributions from different sources to local air pollution. It can explicitly distinguish between regional–background and local–urban air pollution, allowing for fully consistent downscaling schemes. The method can be implemented in existing Eulerian chemical transport models and can be used to distinguish the contribution of a large number of emission sources to air pollution in every receptor grid cell within one single model simulation and thus to provide detailed maps of the origin of the pollutants. Hence, it can be used for time-critical operational services by providing scientific information as input for local policy decisions on air pollution abatement. The main limitation in its current version is that nonlinear chemical processes are not accounted for and only primary pollutants can be addressed. In this paper we provide a technical description of the method and discuss various applications for scientific and policy purposes.

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17

Frohn, L. M., J. H. Christensen, J. Brandt, C. Geels, and K. M. Hansen. "Validation of a 3-D hemispheric nested air pollution model." Atmospheric Chemistry and Physics Discussions 3, no. 4 (July 8, 2003): 3543–88. http://dx.doi.org/10.5194/acpd-3-3543-2003.

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Abstract. Several air pollution transport models have been developed at the National Environmental Research Institute in Denmark over the last decade (DREAM, DEHM, ACDEP and DEOM). A new 3-D nested Eulerian transport-chemistry model: REGIonal high resolutioN Air pollution model (REGINA) is based on modules and parameterisations from these models as well as new methods. The model covers the majority of the Northern Hemisphere with currently one nest implemented. The horizontal resolution in the mother domain is 150 km × 150 km, and the nesting factor is three. A chemical scheme (originally 51 species) has been extended with a detailed description of the ammonia chemistry and implemented in the model. The mesoscale numerical weather prediction model MM5v2 is used as meteorological driver for the model. The concentrations of air pollutants, such as sulphur and nitrogen in various forms, have been calculated, applying zero nesting and one nest. The model setup is currently being validated by comparing calculated values of concentrations to measurements from approximately 100 stations included in the European Monitoring and Evalutation Programme (EMEP). The present paper describes the physical processes and parameterisations of the model together with the modifications of the chemical scheme. Validation of the model calculations by comparison to EMEP measurements for a summer and a winter month is shown and discussed. Furthermore, results from a sensitivity study of the model performance with respect to resolution in emission and meteorology input data is presented. Finally the future prospects of the model are discussed. The overall validation shows that the model performs well with respect to correlation for both monthly and daily mean values.

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18

Dronamraju, Mohan, Leonard K. Peters, Gregory R. Carmichael, Prasad Kasibhatla, and Cho Seog-Yeon. "An Eulerian transport/transformation/removal model for SO2 and sulfate—III. Comparison with the July 1974 sure database." Atmospheric Environment (1967) 22, no. 9 (January 1988): 2003–11. http://dx.doi.org/10.1016/0004-6981(88)90089-3.

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19

Hamer, Paul D., Sam-Erik Walker, Gabriela Sousa-Santos, Matthias Vogt, Dam Vo-Thanh, Susana Lopez-Aparicio, Philipp Schneider, Martin O. P. Ramacher, and Matthias Karl. "The urban dispersion model EPISODE v10.0 – Part 1: An Eulerian and sub-grid-scale air quality model and its application in Nordic winter conditions." Geoscientific Model Development 13, no. 9 (September 17, 2020): 4323–53. http://dx.doi.org/10.5194/gmd-13-4323-2020.

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Abstract. This paper describes the Eulerian urban dispersion model EPISODE. EPISODE was developed to address a need for an urban air quality model in support of policy, planning, and air quality management in the Nordic, specifically Norwegian, setting. It can be used for the calculation of a variety of airborne pollutant concentrations, but we focus here on the implementation and application of the model for NO2 pollution. EPISODE consists of an Eulerian 3D grid model with embedded sub-grid dispersion models (e.g. a Gaussian plume model) for dispersion of pollution from line (i.e. roads) and point sources (e.g. chimney stacks). It considers the atmospheric processes advection, diffusion, and an NO2 photochemistry represented using the photostationary steady-state approximation for NO2. EPISODE calculates hourly air concentrations representative of the grids and at receptor points. The latter allow EPISODE to estimate concentrations representative of the levels experienced by the population and to estimate their exposure. This methodological framework makes it suitable for simulating NO2 concentrations at fine-scale resolution (<100 m) in Nordic environments. The model can be run in an offline nested mode using output concentrations from a global or regional chemical transport model and forced by meteorology from an external numerical weather prediction model; it also can be driven by meteorological observations. We give a full description of the overall model function and its individual components. We then present a case study for six Norwegian cities whereby we simulate NO2 pollution for the entire year of 2015. The model is evaluated against in situ observations for the entire year and for specific episodes of enhanced pollution during winter. We evaluate the model performance using the FAIRMODE DELTA Tool that utilises traditional statistical metrics, e.g. root mean square error (RMSE), Pearson correlation R, and bias, along with some specialised tests for air quality model evaluation. We find that EPISODE attains the DELTA Tool model quality objective in all of the stations we evaluate against. Further, the other statistical evaluations show adequate model performance but that the model scores greatly improved correlations during winter and autumn compared to the summer. We attribute this to the use of the photostationary steady-state scheme for NO2, which should perform best in the absence of local ozone photochemical production. Oslo does not comply with the NO2 annual limit set in the 2008/50/EC directive (AQD). NO2 pollution episodes with the highest NO2 concentrations, which lead to the occurrence of exceedances of the AQD hourly limit for NO2, occur primarily in the winter and autumn in Oslo, so this strongly supports the use of EPISODE for application to these wintertime events. Overall, we conclude that the model is suitable for an assessment of annual mean NO2 concentrations and also for the study of hourly NO2 concentrations in the Nordic winter and autumn environment. Further, in this work we conclude that it is suitable for a range of policy applications specific to NO2 that include pollution episode analysis, evaluation of seasonal statistics, policy and planning support, and air quality management. Lastly, we identify a series of model developments specifically designed to address the limitations of the current model assumptions. Part 2 of this two-part paper discusses the CityChem extension to EPISODE, which includes a number of implementations such as a more comprehensive photochemical scheme suitable for describing more chemical species and a more diverse range of photochemical environments, as well as a more advanced treatment of the sub-grid dispersion.

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Marr, Linsey C., Gregory S. Noblet, and Robert A. Harley. "Formation of photochemical air pollution in central California 2. Impact of revised emissions on Eulerian model predictions." Journal of Geophysical Research: Atmospheres 107, no. D6 (March 27, 2002): ACH 6–1—ACH 6–11. http://dx.doi.org/10.1029/2001jd000690.

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21

van Stun, Th L., and F. T. M. Nieuwstadt. "On the relation between a lagrangian and a eulerian model of diffusion in homogeneous, stationary and non-gaussian turbulence." Atmospheric Environment (1967) 20, no. 6 (January 1986): 1111–20. http://dx.doi.org/10.1016/0004-6981(86)90143-5.

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22

Atanassov, D., and D. Galeriu. "Rain scavenging of tritiated water vapour: a numerical Eulerian stationary model." Journal of Environmental Radioactivity 102, no. 1 (January 2011): 43–52. http://dx.doi.org/10.1016/j.jenvrad.2010.09.001.

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23

Pichelstorfer, Lukas, Renate Winkler-Heil, and Werner Hofmann. "Lagrangian/Eulerian model of coagulation and deposition of inhaled particles in the human lung." Journal of Aerosol Science 64 (October 2013): 125–42. http://dx.doi.org/10.1016/j.jaerosci.2013.05.007.

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24

Sodemann, H., M. Pommier, S. R. Arnold, S. A. Monks, K. Stebel, J. F. Burkhart, J. W. Hair, et al. "Episodes of cross-polar transport in the Arctic troposphere during July 2008 as seen from models, satellite, and aircraft observations." Atmospheric Chemistry and Physics 11, no. 8 (April 19, 2011): 3631–51. http://dx.doi.org/10.5194/acp-11-3631-2011.

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Abstract. During the POLARCAT summer campaign in 2008, two episodes (2–5 July and 7–10 July 2008) occurred where low-pressure systems traveled from Siberia across the Arctic Ocean towards the North Pole. The two cyclones had extensive smoke plumes from Siberian forest fires and anthropogenic sources in East Asia embedded in their associated air masses, creating an excellent opportunity to use satellite and aircraft observations to validate the performance of atmospheric transport models in the Arctic, which is a challenging model domain due to numerical and other complications. Here we compare transport simulations of carbon monoxide (CO) from the Lagrangian transport model FLEXPART and the Eulerian chemical transport model TOMCAT with retrievals of total column CO from the IASI passive infrared sensor onboard the MetOp-A satellite. The main aspect of the comparison is how realistic horizontal and vertical structures are represented in the model simulations. Analysis of CALIPSO lidar curtains and in situ aircraft measurements provide further independent reference points to assess how reliable the model simulations are and what the main limitations are. The horizontal structure of mid-latitude pollution plumes agrees well between the IASI total column CO and the model simulations. However, finer-scale structures are too quickly diffused in the Eulerian model. Applying the IASI averaging kernels to the model data is essential for a meaningful comparison. Using aircraft data as a reference suggests that the satellite data are biased high, while TOMCAT is biased low. FLEXPART fits the aircraft data rather well, but due to added background concentrations the simulation is not independent from observations. The multi-data, multi-model approach allows separating the influences of meteorological fields, model realisation, and grid type on the plume structure. In addition to the very good agreement between simulated and observed total column CO fields, the results also highlight the difficulty to identify a data set that most realistically represents the actual pollution state of the Arctic atmosphere.

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Nie, Wen, and Wei Min Cheng. "Regularity of Dust Distributing in Fully Mechanized Caving Face and Negative Pressure Spray Dust-Settling Technology." Applied Mechanics and Materials 246-247 (December 2012): 624–28. http://dx.doi.org/10.4028/www.scientific.net/amm.246-247.624.

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The mathematical model of solving two-phase flow of gas and dust particles was built by established the k-ε equation. Moreover, by basing on Eulerian-Lagrangian model and using FLUENT software, the diffusion rule of dust pollution in full-mechanized caving face was confirmed. Based on negative pressure spray dust-settling mechanism, negative pressure spray technology was developed between hydraulic supports, in drawing opening position and shearer, and it was determined by the optimal spray pressure for 4 MPa. After negative pressure spray technology was applied in fully mechanized caving face, the dust concentration was down significantly.

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26

Bartnicki, Jerzy. "An Eulerian model for atmospheric transport of heavy metals over Europe: Model description and preliminary results." Water, Air, & Soil Pollution 75, no. 3-4 (June 1994): 227–63. http://dx.doi.org/10.1007/bf00482939.

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27

Degrazia, Gervásio Annes, Guilherme Sausen Welter, Adrián Roberto Wittwer, Jonas da Costa Carvalho, Débora Regina Roberti, Otávio Costa Acevedo, Osvaldo L. L. Moraes, and Haroldo F. de Campos Velho. "Estimation of the Lagrangian Kolmogorov constant from Eulerian measurements for distinct Reynolds number with application to pollution dispersion model." Atmospheric Environment 42, no. 10 (March 2008): 2415–23. http://dx.doi.org/10.1016/j.atmosenv.2007.12.018.

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Lagzi, I., D. Kármán, T. Turányi, A. S. Tomlin, and L. Haszpra. "Simulation of the dispersion of nuclear contamination using an adaptive Eulerian grid model." Journal of Environmental Radioactivity 75, no. 1 (January 2004): 59–82. http://dx.doi.org/10.1016/j.jenvrad.2003.11.003.

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29

Brandt, J., J. D. Silver, L. M. Frohn, C. Geels, A. Gross, A. B. Hansen, K. M. Hansen, et al. "An integrated model study for Europe and North America using the Danish Eulerian Hemispheric Model with focus on intercontinental transport of air pollution." Atmospheric Environment 53 (June 2012): 156–76. http://dx.doi.org/10.1016/j.atmosenv.2012.01.011.

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Camps, J., J. Massons, and M. R. Soler. "Numerical modelling of pollutant dispersion in sea breeze conditions." Annales Geophysicae 14, no. 6 (June 30, 1996): 665–77. http://dx.doi.org/10.1007/s00585-996-0665-7.

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Abstract. The characteristics of air pollution in Tarragona (Spain) were investigated. Tarragona has an important petrochemical industry in a coastal region with a complex terrain. The numerical study was made in sea breeze conditions with a three-dimensional mesoscale model. Temporal and spatial variations of the wind fields have been used in the Eulerian equation for a non-reactive pollutant. The results of this study reveal the complexity of the dispersion patterns due to the combined effects of the sea breeze circulation and the orography. This work presents a comparison between the model output and the observed wind data by sodar and surface wind measurements. The evaluation shows that the model is capable of providing very realistic wind fields within this domain.

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Zare, A., J. Brandt, J. H. Christensen, and P. Irannejad. "Evaluation of two isoprene emission models for use in a long-range air pollution model." Atmospheric Chemistry and Physics Discussions 12, no. 4 (April 10, 2012): 9247–81. http://dx.doi.org/10.5194/acpd-12-9247-2012.

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Abstract. Knowledge about isoprene emissions and concentration distribution is important for chemistry transport models (CTMs), because isoprene acts as a precursor for tropospheric ozone and subsequently affects the atmospheric concentrations of many other atmospheric compounds. Isoprene has a short lifetime, and hence it is very difficult to evaluate its emission estimates against measurements. For this reason, we coupled two isoprene emission models with the Danish Eulerian Hemispheric Model (DEHM), and evaluated the simulated background ozone concentrations based on different models for isoprene emissions. In this research, results of using the two global biogenic emission models; GEIA (Global Emissions Inventory Activity) and MEGAN (the global Model of Emissions of Gases and Aerosols from Nature) are compared and evaluated. The total annual emissions of isoprene for the year 2006 estimated by using MEGAN is 732 Tg yr−1 for an extended area of the Northern Hemisphere, which is 50% higher than that estimated by using GEIA. The overall feature of the emissions from the two models are quite similar, but significant differences are found mainly in Africa's savannah and the rain forests of South America, and in some subtropical regions, such as the Middle East, India and the southern part of North America. Differences in spatial distribution of emission factors are found to be a key source of these discrepancies. In spite of the short life-time of isoprene, a direct evaluation of isoprene concentrations using the two biogenic emission models has been made against available measurements in Europe. Results show that the two models in general represent the measurements well and that the CTM is able to simulate isoprene concentrations. Additionally, investigation of ozone concentrations resulting from the two biogenic emission models show that isoprene simulated by MEGAN strongly affects the ozone production in the African savannah; the effect is up to 20% more than that obtained using GEIA. In contrast, the impact of using GEIA is higher in the Amazon region with more than 15% higher ozone concentrations compared to that of using MEGAN. Comparing the results for ozone concentrations for Europe obtained by using the two different models with measurements, show that the MEGAN emission model improves the model performance significantly in the Mediterranean area.

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Frydendall, J., J. Brandt, and J. H. Christensen. "Implementation and testing of a simple data assimilation algorithm in the regional air pollution forecast model, DEOM." Atmospheric Chemistry and Physics 9, no. 15 (August 4, 2009): 5475–88. http://dx.doi.org/10.5194/acp-9-5475-2009.

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Abstract. A simple data assimilation algorithm based on statistical interpolation has been developed and coupled to a long-range chemistry transport model, the Danish Eulerian Operational Model (DEOM), applied for air pollution forecasting at the National Environmental Research Institute (NERI), Denmark. In this paper, the algorithm and the results from experiments designed to find the optimal setup of the algorithm are described. The algorithm has been developed and optimized via eight different experiments where the results from different model setups have been tested against measurements from the EMEP (European Monitoring and Evaluation Programme) network covering a half-year period, April–September 1999. The best performing setup of the data assimilation algorithm for surface ozone concentrations has been found, including the combination of determining the covariances using the Hollingsworth method, varying the correlation length according to the number of adjacent observation stations and applying the assimilation routine at three successive hours during the morning. Improvements in the correlation coefficient in the range of 0.1 to 0.21 between the results from the reference and the optimal configuration of the data assimilation algorithm, were found. The data assimilation algorithm will in the future be used in the operational THOR integrated air pollution forecast system, which includes the DEOM.

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Frydendall, J., J. Brandt, and J. H. Christensen. "Implementation and testing of a simple data assimilation algorithm in the regional air pollution forecast model, DEOM." Atmospheric Chemistry and Physics Discussions 9, no. 2 (March 23, 2009): 7645–80. http://dx.doi.org/10.5194/acpd-9-7645-2009.

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Abstract. A simple data assimilation algorithm based on statistical interpolation has been developed and coupled to a long-range chemistry transport model, the Danish Eulerian Operational Model (DEOM), applied for air pollution forecasting at the National Environmental Research Institute (NERI), Denmark. In this paper, the algorithm and the results from experiments designed to find the optimal setup of the algorithm are described. The algorithm has been developed and optimized via eight different experiments where the results from different model setups have been tested against measurements from the EMEP (European Monitoring and Evaluation Programme) network covering a half-year period, April–September 1999. The best performing setup of the data assimilation algorithm for surface ozone concentrations has been found, including the combination of determining the covariances using the Hollingsworth method, varying the correlation length according to the number of adjacent observation stations and applying the assimilation routine at three successive hours during the morning. Improvements in the correlation coefficient in the range of 0.1 to 0.21 between the results from the reference and the optimal configuration of the data assimilation algorithm, were found. The data assimilation algorithm will in the future be used in the operational THOR integrated air pollution forecast system, which includes the DEOM.

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Kota, Sri Harsha, Qi Ying, and Yunlong Zhang. "Simulating near-road reactive dispersion of gaseous air pollutants using a three-dimensional Eulerian model." Science of The Total Environment 454-455 (June 2013): 348–57. http://dx.doi.org/10.1016/j.scitotenv.2013.03.039.

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Zare, A., J. H. Christensen, P. Irannejad, and J. Brandt. "Evaluation of two isoprene emission models for use in a long-range air pollution model." Atmospheric Chemistry and Physics 12, no. 16 (August 16, 2012): 7399–412. http://dx.doi.org/10.5194/acp-12-7399-2012.

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Abstract. Knowledge about isoprene emissions and concentration distribution is important for chemistry transport models (CTMs), because isoprene acts as a precursor for tropospheric ozone and subsequently affects the atmospheric concentrations of many other atmospheric compounds. Isoprene has a short lifetime, and hence it is very difficult to evaluate its emission estimates against measurements. For this reason, we coupled two isoprene emission models with the Danish Eulerian Hemispheric Model (DEHM), and evaluated the simulated background ozone concentrations based on different models for isoprene emissions. In this research, results of using the two global biogenic emission models; GEIA (Global Emissions Inventory Activity) and MEGAN (the global Model of Emissions of Gases and Aerosols from Nature) are compared and evaluated. The total annual emissions of isoprene for the year 2006 estimated by using MEGAN is 592 Tg yr−1 for an extended area of the Northern Hemisphere, which is 21% higher than that estimated by using GEIA. The overall feature of the emissions from the two models is quite similar, but differences are found mainly in Africa's savannah and in the southern part of North America. Differences in spatial distribution of emission factors are found to be a key source of these discrepancies. In spite of the short life-time of isoprene, a direct evaluation of isoprene concentrations using the two biogenic emission models in DEHM has been made against available measurements in Europe. Results show an agreement between two models simulations and the measurements in general and that the CTM is able to simulate isoprene concentrations. Additionally, investigation of ozone concentrations resulting from the two biogenic emission models show that isoprene simulated by MEGAN strongly affects the ozone production in the African savannah; the effect is up to 10% more than that obtained using GEIA. In contrast, the impact of using GEIA is higher in the Amazon region with more than 8% higher ozone concentrations compared to that of using MEGAN. Comparing the ozone concentrations obtained by DEHM using the two different isoprene models with measurements from Europe and North America, show an agreement on the hourly, mean daily and daily maximum values. However, the average of ozone daily maximum value simulated by using MEGAN is slightly closer to the measured value for the average of all measuring sites in Europe.

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Soldati, Alfredo. "Cost-Efficiency Analysis of a Model Wire-Plate Electrostatic Precipitator via DNS Based Eulerian Particle Transport Approach." Aerosol Science and Technology 37, no. 2 (February 2003): 171–82. http://dx.doi.org/10.1080/02786820300957.

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Sodemann, H., M. Pommier, S. R. Arnold, S. A. Monks, K. Stebel, J. F. Burkhart, J. W. Hair, et al. "Episodes of cross-polar transport in the Arctic troposphere during July 2008 as seen from models, satellite, and aircraft observations." Atmospheric Chemistry and Physics Discussions 10, no. 11 (November 5, 2010): 26361–410. http://dx.doi.org/10.5194/acpd-10-26361-2010.

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Abstract. During the POLARCAT summer campaign in 2008, two episodes (2–5 July and 7–10 July 2008) occurred where low-pressure systems traveled from Siberia across the Arctic Ocean towards the North Pole. The two cyclones had extensive smoke plumes embedded in their associated air masses, creating an excellent opportunity to use satellite and aircraft observations to validate the performance of atmospheric transport models in the Arctic, which is a challenging model domain due to numerical and other complications. Here we compare transport simulations of carbon monoxide (CO) from the Lagrangian transport model FLEXPART, the Eulerian chemical transport model TOMCAT, and for numerical aspects the limited-area chemical transport model WRF-Chem. Retrievals of total column CO from the IASI passive infrared sensor onboard the MetOp-A satellite are used as a total column CO reference for the two simulations. Main aspect of the comparison is how realistic horizontal and vertical structures are represented in the model simulations. Analysis of CALIPSO lidar curtains and in situ aircraft measurements provide further independent reference points to assess how reliable the model simulations are and what the main limitations are. The horizontal structure of mid-latitude pollution plumes agrees well between the IASI total column CO and the model simulations. However, finer-scale structures are too quickly diffused in the Eulerian models. Aircraft data suggest that the satellite data are biased high, while TOMCAT and WRF-Chem are biased low. FLEXPART fits the aircraft data rather well, but due to added background concentrations the simulation is not independent from observations. The multi-data, multi-model approach allows separating the influences of meteorological fields, model realisation, and grid type on the plume structure. In addition to the very good agreement between simulated and observed total column CO fields, the results also highlight the difficulty to identify a data set that most realistically represents the actual state of the atmosphere.

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Aleksankina, Ksenia, Stefan Reis, Massimo Vieno, and Mathew R. Heal. "Advanced methods for uncertainty assessment and global sensitivity analysis of an Eulerian atmospheric chemistry transport model." Atmospheric Chemistry and Physics 19, no. 5 (March 7, 2019): 2881–98. http://dx.doi.org/10.5194/acp-19-2881-2019.

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Abstract. Atmospheric chemistry transport models (ACTMs) are extensively used to provide scientific support for the development of policies to mitigate the detrimental effects of air pollution on human health and ecosystems. Therefore, it is essential to quantitatively assess the level of model uncertainty and to identify the model input parameters that contribute the most to the uncertainty. For complex process-based models, such as ACTMs, uncertainty and global sensitivity analyses are still challenging and are often limited by computational constraints due to the requirement of a large number of model runs. In this work, we demonstrate an emulator-based approach to uncertainty quantification and variance-based sensitivity analysis for the EMEP4UK model (regional application of the European Monitoring and Evaluation Programme Meteorological Synthesizing Centre-West). A separate Gaussian process emulator was used to estimate model predictions at unsampled points in the space of the uncertain model inputs for every modelled grid cell. The training points for the emulator were chosen using an optimised Latin hypercube sampling design. The uncertainties in surface concentrations of O3, NO2, and PM2.5 were propagated from the uncertainties in the anthropogenic emissions of NOx, SO2, NH3, VOC, and primary PM2.5 reported by the UK National Atmospheric Emissions Inventory. The results of the EMEP4UK uncertainty analysis for the annually averaged model predictions indicate that modelled surface concentrations of O3, NO2, and PM2.5 have the highest level of uncertainty in the grid cells comprising urban areas (up to ±7 %, ±9 %, and ±9 %, respectively). The uncertainty in the surface concentrations of O3 and NO2 were dominated by uncertainties in NOx emissions combined from non-dominant sectors (i.e. all sectors excluding energy production and road transport) and shipping emissions. Additionally, uncertainty in O3 was driven by uncertainty in VOC emissions combined from sectors excluding solvent use. Uncertainties in the modelled PM2.5 concentrations were mainly driven by uncertainties in primary PM2.5 emissions and NH3 emissions from the agricultural sector. Uncertainty and sensitivity analyses were also performed for five selected grid cells for monthly averaged model predictions to illustrate the seasonal change in the magnitude of uncertainty and change in the contribution of different model inputs to the overall uncertainty. Our study demonstrates the viability of a Gaussian process emulator-based approach for uncertainty and global sensitivity analyses, which can be applied to other ACTMs. Conducting these analyses helps to increase the confidence in model predictions. Additionally, the emulators created for these analyses can be used to predict the ACTM response for any other combination of perturbed input emissions within the ranges set for the original Latin hypercube sampling design without the need to rerun the ACTM, thus allowing for fast exploratory assessments at significantly reduced computational costs.

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Karl, Matthias, Sam-Erik Walker, Sverre Solberg, and Martin O. P. Ramacher. "The Eulerian urban dispersion model EPISODE – Part 2: Extensions to the source dispersion and photochemistry for EPISODE–CityChem v1.2 and its application to the city of Hamburg." Geoscientific Model Development 12, no. 8 (August 1, 2019): 3357–99. http://dx.doi.org/10.5194/gmd-12-3357-2019.

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Abstract. This paper describes the CityChem extension of the Eulerian urban dispersion model EPISODE. The development of the CityChem extension was driven by the need to apply the model in largely populated urban areas with highly complex pollution sources of particulate matter and various gaseous pollutants. The CityChem extension offers a more advanced treatment of the photochemistry in urban areas and entails specific developments within the sub-grid components for a more accurate representation of dispersion in proximity to urban emission sources. Photochemistry on the Eulerian grid is computed using a numerical chemistry solver. Photochemistry in the sub-grid components is solved with a compact reaction scheme, replacing the photo-stationary-state assumption. The simplified street canyon model (SSCM) is used in the line source sub-grid model to calculate pollutant dispersion in street canyons. The WMPP (WORM Meteorological Pre-Processor) is used in the point source sub-grid model to calculate the wind speed at plume height. The EPISODE–CityChem model integrates the CityChem extension in EPISODE, with the capability of simulating the photochemistry and dispersion of multiple reactive pollutants within urban areas. The main focus of the model is the simulation of the complex atmospheric chemistry involved in the photochemical production of ozone in urban areas. The ability of EPISODE–CityChem to reproduce the temporal variation of major regulated pollutants at air quality monitoring stations in Hamburg, Germany, was compared to that of the standard EPISODE model and the TAPM (The Air Pollution Model) air quality model using identical meteorological fields and emissions. EPISODE–CityChem performs better than EPISODE and TAPM for the prediction of hourly NO2 concentrations at the traffic stations, which is attributable to the street canyon model. Observed levels of annual mean ozone at the five urban background stations in Hamburg are captured by the model within ±15 %. A performance analysis with the FAIRMODE DELTA tool for air quality in Hamburg showed that EPISODE–CityChem fulfils the model performance objectives for NO2 (hourly), O3 (daily max. of the 8 h running mean) and PM10 (daily mean) set forth in the Air Quality Directive, qualifying the model for use in policy applications. Envisaged applications of the EPISODE–CityChem model are urban air quality studies, emission control scenarios in relation to traffic restrictions and the source attribution of sector-specific emissions to observed levels of air pollutants at urban monitoring stations.

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Flaounas, E., I. Coll, A. Armengaud, and C. Schmechtig. "The representation of dust transport and missing urban sources as major issues for the simulation of PM episodes in a Mediterranean area." Atmospheric Chemistry and Physics 9, no. 20 (October 27, 2009): 8091–101. http://dx.doi.org/10.5194/acp-9-8091-2009.

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Abstract. Due to its adverse effects on human health, atmospheric particulate matter (PM) constitutes a growing challenge for air quality management. It is also a complex subject of study. The understanding of its atmospheric evolution is indeed made difficult by the wide number of sources and the numerous processes that govern its evolution in the troposphere. As a consequence, the representation of particulate matter in chemistry-transport models needs to be permanently evaluated and enhanced in order to refine our comprehension of PM pollution events and to propose consistent environmental policies. The study presented here focuses on two successive summer particulate pollution episodes that occurred on the French Mediterranean coast. We identify and analyze the constitutive elements of the first and more massive episode and we discuss their representation within a eulerian model. The results show that the model fails in reproducing the variability and the amplitude of dust import from western Africa, and that it constitutes a strong bias in PM daily forecasts. We then focus on the lack of diurnal variability in the model, which is attributed to missing urban sources in standard emission inventories, and notably the resuspension of particles by urban road traffic. Through a sensitivity study based on PM and NOx measurements, we assess the sensitivity of PM to local emissions and the need to reconsider road traffic PM sources. In parallel, by coupling the CHIMERE-DUST model outputs to our simulation, we show that the representation of transcontinental dust transport allows a much better representation of atmospheric particles in southern France, and that it is needed in the frame of air quality management for the quantification of the anthropogenic part of particulate matter pollution.

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Zhang, L., D. J. Jacob, X. Yue, N. V. Downey, D. A. Wood, and D. Blewitt. "Sources contributing to background surface ozone in the US Intermountain West." Atmospheric Chemistry and Physics Discussions 13, no. 10 (October 8, 2013): 25871–909. http://dx.doi.org/10.5194/acpd-13-25871-2013.

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Abstract. We quantify the sources contributing to background surface ozone concentrations in the US Intermountain West by using the GEOS-Chem chemical transport model with 1/2° × 2/3° horizontal resolution to interpret CASTNet ozone monitoring data for 2006–2008. We isolate contributions from lightning, wildfires, the stratosphere, and California pollution. Lightning increases mean surface ozone in summer by 10 ppbv in the Intermountain West, with moderate variability; constraining the model source with flash rate observations is important. Using a daily wildfire inventory compiled from fire reports in the western US generates high-ozone events in excess of 80 ppbv in GEOS-Chem. The CASTNet observations show no evidence of such events. Models in general may overestimate ozone concentrations in fresh plumes because of inadequate fire plume chemistry. The highest ozone concentrations observed in the Intermountain West (>75 ppbv) in spring are associated with stratospheric intrusions. The model captures the timing of these intrusions but not their magnitude, reflecting numerical diffusion intrinsic to Eulerian models. This can be corrected statistically through a relationship between model bias and the model-diagnosed magnitude of stratospheric influence; with this correction, models may still be useful to forecast and interpret high-ozone events from stratospheric intrusions. We show that discrepancy between models in diagnosing stratospheric influence is due in part to differences in definition, i.e., whether stratospheric ozone is diagnosed as produced in the stratosphere (GEOS-Chem definition) or as transported from above the tropopause. The latter definition can double the diagnosed stratospheric influence in surface air by labeling as "stratospheric" any ozone produced in the troposphere and temporarily transported to the stratosphere. California pollution influence in the Intermountain West frequently exceeds 10 ppbv but is generally not correlated with the highest ozone events.

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Zhang, L., D. J. Jacob, X. Yue, N. V. Downey, D. A. Wood, and D. Blewitt. "Sources contributing to background surface ozone in the US Intermountain West." Atmospheric Chemistry and Physics 14, no. 11 (June 2, 2014): 5295–309. http://dx.doi.org/10.5194/acp-14-5295-2014.

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Abstract. We quantify the sources contributing to background surface ozone concentrations in the US Intermountain West by using the GEOS-Chem chemical transport model with 1 / 2° × 2 / 3° horizontal resolution to interpret the Clean Air Status and Trends Network (CASTNet) ozone monitoring data for 2006–2008. We isolate contributions from lightning, wildfires, the stratosphere, and California pollution. Lightning emissions are constrained by observations and wildfire emissions are estimated from daily fire reports. We find that lightning increases mean surface ozone in summer by 10 ppbv in the Intermountain West, with moderate variability. Wildfire plumes generate high-ozone events in excess of 80 ppbv in GEOS-Chem, but CASTNet ozone observations in the Intermountain West show no enhancements during these events nor do they show evidence of regional fire influence. Models may overestimate ozone production in fresh fire plumes because of inadequate chemistry and grid-scale resolution. The highest ozone concentrations observed in the Intermountain West (> 75 ppbv) in spring are associated with stratospheric intrusions. The model captures the timing of these intrusions but not their magnitude, reflecting numerical diffusion intrinsic to Eulerian models. This can be corrected statistically through a relationship between model bias and the model-diagnosed magnitude of stratospheric influence; with this correction, models may still be useful to forecast and interpret high-ozone events from stratospheric intrusions. We show that discrepancy between models in diagnosing stratospheric influence is due in part to differences in definition, i.e., whether stratospheric ozone is diagnosed as produced in the stratosphere (GEOS-Chem definition) or as transported from above the tropopause. The latter definition can double the diagnosed stratospheric influence in surface air by labeling as "stratospheric" any ozone produced in the troposphere and temporarily transported to the stratosphere. California pollution influence in the Intermountain West frequently exceeds 10 ppbv but is generally not correlated with the highest ozone events.

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43

Flaounas, E., I. Coll, A. Armengaud, and C. Schmechtig. "The representation of dust transport and missing urban sources as major issues for the simulation of PM episodes in a Mediterranean area." Atmospheric Chemistry and Physics Discussions 9, no. 4 (July 15, 2009): 15295–325. http://dx.doi.org/10.5194/acpd-9-15295-2009.

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Abstract. Due to its adverse effects on human health, atmospheric particulate matter (PM) constitutes a growing challenge for air quality management. It is also a complex subject of study. The understanding of its atmospheric evolution is indeed made difficult by the wide number of sources and the numerous processes that govern its evolution in the troposphere. As a consequence, the representation of particulate matter in chemistry-transport models needs to be permanently evaluated and enhanced in order to refine our comprehension of PM pollution events and to propose consistent environmental policies. The study presented here focuses on a summer particulate pollution episode that occurred on the French Mediterranean coast. It aims at identifying the constitutive elements of this episode and to discuss its representation within a eulerian model. We first highlight the major role of dust transport from western Africa in the formation of a multi-day PM event. This result shows that dust import has to be regarded as a potentially major participant to PM events in Europe, even when considering moderate peak values. In parallel we focus on a lack of diurnal variability in the model, which is attributed to missing urban sources in standard emission inventories, and notably the resuspension of particles by urban road traffic. Through a sensitivity study based on PM and NOx measurements, we could assess the amplitude of this lack as well as the need to reconsider road traffic PM sources. In parallel, by coupling the CHIMERE-DUST model outputs to our simulation, we could show that the representation of transcontinental dust transport is a necessity for a better simulation of atmospheric particles in Southern Europe, and – in the frame of air quality management – for the quantification of the anthropogenic part of particulate matter pollution.

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Elfverson, Daniel, and Christian Lejon. "Use and Scalability of OpenFOAM for Wind Fields and Pollution Dispersion with Building- and Ground-Resolving Topography." Atmosphere 12, no. 9 (August 31, 2021): 1124. http://dx.doi.org/10.3390/atmos12091124.

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Complex flow and pollutant dispersion simulations in real urban settings were investigated by using computational fluid dynamics (CFD) simulations with the SST k−ω Reynolds-averaged Navier–Stokes (RANS) equation with OpenFOAM. The model was validated with a wind-tunnel experiment using two surface-mounted cubes in tandem, and the flow features were reproduced with the correct qualitative behaviour. The real urban geometry of the Parade Square in Warsaw, Poland was represented with both laser-scanning data for the ground geometry and the CityGML standard to describe the buildings as an example. The Eulerian dispersion of a passive scalar and the flow behaviour could be resolved within minutes over a computational domain with a size of 958 × 758 m2 and a height of 300 m with over 2 M cells due to the good and strong parallel scalability in OpenFOAM. This implies that RANS modelling with parallel computing in OpenFOAM can potentially be used as a tool for situational awareness on a local urban scale; however, entire cities would be too large.

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van den Bremer, T. S., and Ø. Breivik. "Stokes drift." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, no. 2111 (December 11, 2017): 20170104. http://dx.doi.org/10.1098/rsta.2017.0104.

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During its periodic motion, a particle floating at the free surface of a water wave experiences a net drift velocity in the direction of wave propagation, known as the Stokes drift (Stokes 1847 Trans. Camb. Philos. Soc. 8 , 441–455). More generally, the Stokes drift velocity is the difference between the average Lagrangian flow velocity of a fluid parcel and the average Eulerian flow velocity of the fluid. This paper reviews progress in fundamental and applied research on the induced mean flow associated with surface gravity waves since the first description of the Stokes drift, now 170 years ago. After briefly reviewing the fundamental physical processes, most of which have been established for decades, the review addresses progress in laboratory and field observations of the Stokes drift. Despite more than a century of experimental studies, laboratory studies of the mean circulation set up by waves in a laboratory flume remain somewhat contentious. In the field, rapid advances are expected due to increasingly small and cheap sensors and transmitters, making widespread use of small surface-following drifters possible. We also discuss remote sensing of the Stokes drift from high-frequency radar. Finally, the paper discusses the three main areas of application of the Stokes drift: in the coastal zone, in Eulerian models of the upper ocean layer and in the modelling of tracer transport, such as oil and plastic pollution. Future climate models will probably involve full coupling of ocean and atmosphere systems, in which the wave model provides consistent forcing on the ocean surface boundary layer. Together with the advent of new space-borne instruments that can measure surface Stokes drift, such models hold the promise of quantifying the impact of wave effects on the global atmosphere–ocean system and hopefully contribute to improved climate projections. This article is part of the theme issue ‘Nonlinear water waves’.

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Jeričević, A., L. Kraljević, B. Grisogono, H. Fagerli, and Ž. Večenaj. "Parameterization of vertical diffusion and the atmospheric boundary layer height determination in the EMEP model." Atmospheric Chemistry and Physics 10, no. 2 (January 18, 2010): 341–64. http://dx.doi.org/10.5194/acp-10-341-2010.

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Abstract. This paper introduces two changes of the turbulence parameterization for the EMEP (European Monitoring and Evaluation Programme) Eulerian air pollution model: the replacement of the Blackadar in stable and O'Brien in unstable turbulence formulations with an analytical vertical diffusion profile (K(z)) called Grisogono, and a different mixing height determination, based on a bulk Richardson number formulation (RiB). The operational or standard (STD) and proposed new parameterization for eddy diffusivity have been validated in all stability conditions against the observed daily surface nitrogen dioxide (NO2), sulphur dioxide (SO2) and sulphate (SO42−) concentrations at different EMEP stations during the year 2001. A moderate improvement in the correlation coefficient and bias for NO2 and SO2 and a slight improvement for sulphate is found for the most of the analyzed stations with the Grisogono K(z) scheme, which is recommended for further application due to its scientific and technical advantages. The newly extended approach for the mechanical eddy diffusivity is applied to the Large Eddy Simulation data focusing at the bulk properties of the neutral and stable atmospheric boundary layer. A summary and extension of the previous work on the empirical coefficients in neutral and stable conditions is provided with the recommendations to the further model development. Special emphasis is given to the representation of the ABL in order to capture the vertical transport and dispersion of the atmospheric air pollution. Two different schemes for the ABL height determination are evaluated against the radiosounding data in January and July 2001, and against the data from the Cabauw tower, the Netherlands, for the same year. The validation of the ABL parameterizations has shown that the EMEP model is able to reproduce spatial and temporal mixing height variability. Improvements are identified especially in stable conditions with the new ABL height scheme based on the RiB number.

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Azouz, Niramson, Jean-Louis Drouet, Matthias Beekmann, Guillaume Siour, Roy Wichink Kruit, and Pierre Cellier. "Comparison of spatial patterns of ammonia concentration and dry deposition flux between a regional Eulerian chemistry-transport model and a local Gaussian plume model." Air Quality, Atmosphere & Health 12, no. 6 (April 13, 2019): 719–29. http://dx.doi.org/10.1007/s11869-019-00691-y.

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Khazins, Valery M., Valery V. Shuvalov, and Sergey P. Soloviev. "Numerical Modeling of Formation and Rise of Gas and Dust Cloud from Large Scale Commercial Blasting." Atmosphere 11, no. 10 (October 16, 2020): 1112. http://dx.doi.org/10.3390/atmos11101112.

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The emission of dust particles into the atmosphere during rock mass breaking by blasting in ore mining open-pits is one of the factors that determine the ground-level air pollution in the vicinity of pits. The data on dust concentration in the cloud, which is extremely difficult to obtain experimentally for large-scale explosions, is required to calculate the dust dispersion in the wind stream. We have elaborated a Eulerian model to simulate the initial stage of dust cloud formation and rising, and a Navier–Stokes model to simulate thermal rising and mixing with the ambient air. The first model is used to describe the dust cloud formation after a 500 t TNT (Trinitrotoluene equivalent) explosion. The second model based on the Large Eddy Simulation (LES) method is used to predict the height of cloud rising, its mass, and the evolution of dust particles size distribution for explosions of 1–1000 t TNT. It was found that the value of the turbulent eddy viscosity coefficient (Smagorinsky coefficient) depends on both the charge mass and the spatial resolution (grid cell size). The values of the Smagorinsky coefficient were found for charges with a mass of 1–1000 t using a specific grid.

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Hedegaard, G. B., A. Gross, J. H. Christensen, W. May, H. Skov, C. Geels, K. M. Hansen, and J. Brandt. "Modelling the impacts of climate change on tropospheric ozone over three centuries." Atmospheric Chemistry and Physics Discussions 11, no. 2 (February 25, 2011): 6805–43. http://dx.doi.org/10.5194/acpd-11-6805-2011.

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Abstract. The ozone chemistry over three centuries has been simulated based on climate prediction from a global climate model and constant anthropogenic emissions in order to separate out the effects on air pollution from climate change. Four decades in different centuries has been simulated using the chemistry version of the atmospheric long-range transport model; the Danish Eulerian Hemispheric Model (DEHM) forced with meteorology predicted by the ECHAM5/MPI-OM coupled Atmosphere-Ocean General Circulation Model. The largest changes in both meteorology, ozone and its precursors is found in the 21st century, however, also significant changes are found in the 22nd century. At surface level the ozone concentration is predicted to increase due to climate change in the areas where substantial amounts of ozone precursors are emitted. Elsewhere a significant decrease is predicted at the surface. In the free troposphere a general increase is found in the entire Northern Hemisphere except in the tropics, where the ozone concentration is decreasing. In the Arctic the ozone concentration will increase in the entire air column, which most likely is due to changes in transport. The change in temperature, humidity and the naturally emitted Volatile Organic Compounds (VOCs) are governing with respect to changes in ozone both in the past, present and future century.

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Aulinger, Armin, Volker Matthias, and Markus Quante. "An Approach to Temporally Disaggregate Benzo(a)pyrene Emissions and Their Application to a 3D Eulerian Atmospheric Chemistry Transport Model." Water, Air, & Soil Pollution 216, no. 1-4 (July 31, 2010): 643–55. http://dx.doi.org/10.1007/s11270-010-0559-x.

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