A theoretical investigation of large natural barrier effects on SEA breeze and contamination patterns

The degree of contamination of a large population center lying in the proximity of a mountain, is expected to be strongly dependent on the mountain presence due to its significant distortion of the flow fields and diffusion processes. The phenomena become even more complex in the presence of sea breeze occurring in the area during daytime. In accident consequence assessment there is a need to develop suitable analytical tools to be able to predict efficiently and correctly such complex situations. The present work refers to a 1000 m two dimensional mountain range surrounded by sea. The orography under consideration represents an idealized west-east cross section of the Athens basin. The diurnal cycle of the mesoscale circulation developing across the mountainous coastline, as well as the effect on the contamination patterns are studied. The major phenomena occurring are discussed. The exercise is also part of the effort to develop the necessary capability in the ADREA-I code under development in NRCPS ''Demokritos'' to treat domain of any complexity and any atmospheric stability in atmospheric dispersion analysis and accident consequence assessment in general