Contribution A L Etude De La Diffusion Turbulente D Un Polluant Dans L Atmosphere

Air Pollution Modeling and Its Application IX

The interest in air pollution modelling has shown substantial growth over the last five years. This was particularly evident by the increasing number of participants attending the NATO/CCMS International Technical Meetings on Air Pollution modelling and its Application. At the last meeting 118 papers and posters were selected from an abundance of submitted abstracts divided over five modelling topics: (i) model assessment and verification, including policy applications, (ii) air pollution modelling in coastal areas with emphasis on the mediterranean region, (iii) accidental atmospheric releases, including warning systems and regulations, (iv) modelling of global and long-range transport and (v) new developments in turbulent diffusion. A round-table discussion chaired by John Irwin (USA) and Jan Kretzschmar (Belgium) on the harmonization of air pollution models was attended by more than 50 scientists and is reported in these proceedings. The opening paper addressed the main issue of this conference: modelling over complex terrain. Of particular interest were coastal areas where the surface inhomogeneities introduce small-scale circulation and varying atmospheric stability, often combined with a complex topography. As the conference was located on the beautiful island of Crete, problems faced by the host nation, particularly Athens and its environs were obvious examples for consideration. These together with other regions with similar geographical features were addressed. Heavily populated and industrialized as they often are, air quality is generally poor there and emission regulations are desired. Obviously, a major task of air pollution dispersion modelling is to assist policy makers in formulating sensible regulations.

Diffusion and Transport of Pollutants in Atmospheric Mesoscale Flow Fields

In regions as densely populated as Western Europe, prediction of the ecological implications of pollutant transport are important in order to minimise damage in the case of accidents, and to evaluate the possible influence of existing or planned sources. In most cases, such predictions depend on high-speed computation. The present textbook presents a mathematically explicit introduction in eight chapters: 1: An introduction to the basics of fluid dynamics of the atmosphere and the local events and mesoscale processes. 2: The types of PDEs describing atmospheric flows for limited area models, the problem of appropriate boundary conditions describing the topographical constraints, and well-posedness. 3: Thermodynamics of the atmosphere, dry and wet, its stability, and radiation processes, budgets and the influence of their sum. 4: Scaling and similarity laws for stable and convective turbulent atmospheric boundary layers and the influence of inhomogeneous terrain on the advection and the vertical dispersion, and the method of large eddy simulation. 5: Statistical processes in turbulent dispersion, turbulent diffusion and chemical reactions in fluxes. 6: Theoretical modelling of diffusion and dispersion of pollutant gases. 7: The influence of urban heat production on local climate. 8: Atmospheric inversion layers and lapping inversion, the stable boundary layer and nocturnal inversion.

Air Pollution Abstracts