Atmospheric pollutants, modeling

There is the independence of atmospheric pollution model runs on meteorological model computations... 

Dynamic meteorological models, much like air pollution models, strive to describe the physics and thermodynamics of atmospheric motions as accurately as is feasible. Besides being used in conjunction with air quaHty models, they ate also used for weather forecasting. Like air quaHty models, dynamic meteorological models solve a set of partial differential equations (also called primitive equations). This set of equations, which ate fundamental to the fluid mechanics of the atmosphere, ate referred to as the Navier-Stokes equations, and describe the conservation of mass and momentum. They ate combined with equations describing energy conservation and thermodynamics in a moving fluid (72) ... 

Both receptor and analytical air quahty models have proven to be powerful tools for understanding atmospheric pollutant dynamics and for determining the impact of sources on air quahty. 

The photodecomposition and thermodecomposition of nitromethane have been extensively studied as model systems in combustion, explosion and atmosphere pollution processes[l]. On another hand, nitromethane was selected as a model solvent in experiments aimed at examining non hydrogen-bonded solvent effects in a general acid-base theory of organic molecules [2.3]. This selection is based on the electronic and structural characteristics of nitromethane that has a high dielectric constant, and at the same time cannot form hydrogen bonds with solute molecules. 

Assessments of atmospheric pollution have been made by the regional (MSCE-HM) and the hemispherical (MSCE-HM-Hem) transport models developed in MSC-E (Ilyin et al 2004). The regional model covers the EMEP region (European domain) with the spatial resolution of 50 x 50 km the hemispheric model describes the atmospheric transport within the Northern Hemisphere with the spatial resolution of 2.5 x 2.5 . The main outputs of the modeling include data on heavy metal concentration in the air and precipitation as well as levels of deposition to the surface. Since the negative impact of heavy metals on human health and biota is mainly attributed to their long-term accumulation in environmental media, particular attention has been given to the assessment of their depositions from the atmosphere. 

Hanna, S. R. Urban Air Pollution Model— Why ATDL (Atmospheric Turbulence and Diffusion Laboratory) Contribution File No. 83. (In-house Report) Oak Ridge, Tenn. National Oceanic and Atmospheric Administration, 1973. 19 pp. 

Complete Mix Reactor - The complete mix reactor is also labeled a completely stirred tank reactor. It is a container that has an inhnite diffusion coefficient, such that any chemical that enters the reactor is immediately mixed in with the solvent. In Example 2.8, we used the complete mix reactor assumption to estimate the concentration of three atmospheric pollutants that resulted from an oil spill. We will use a complete mix reactor (in this chapter) to simulate the development of high salt content in dead-end lakes. A series of complete mix reactors may be placed in series to simulate the overall mixing of a one-dimensional system, such as a river. In fact, most computational transport models are a series of complete mix reactors. 

Occupational and toxicological studies have demonstrated adverse health effects from exposure to toxic contaminants. Emissions data from stationary and mobile sources are used in an atmospheric dispersion model to estimate outdoor concentrations of 148 toxic contaminants for each of the 60,803 census tracts in the contiguous United States for 1990. Approximately 10% of all census tracts had estimated concentrations of one or more carcinogenic HAPs at a greater than l-in-10,000 risk level. Twenty-two pollutants with chronic toxicity benchmark concentrations had modeled concentrations in excess of these benchmarks, and approximately 200 census tracts had a modeled concentration 100 times the benchmark for at least one of these pollutants. This comprehensive assessment of air toxics concentrations across the United States indicates hazardous air pollutants may pose a potential public health problem (Woodruff et al., 1998). 

Christensen J.H. (1997). The Danish Eulerian hemispheric model A three-dimensional air pollution model used for the Arctic. Atmospheric Environment, 31(24), 4169-4191. 

Sportisse B. (2000). Box models versus Eulerian models in air pollution modelling. Atmospheric Environment, 35(1), 173-178. 

GEMS (1987) Graphical Exposure Modeling Systems. FAP Fate of Atmospheric Pollutants. 

GRAVES ET AL. Modeling Future Emissions of Atmospheric Pollutants... 

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