Wind field at Attika Basin & Concentration prediction

The DETRACT consists of a set of modules that meet the requirements of studying local to mesoscale wind circulation as well as air pollution levels for terrains of high complexity and real atmospheric conditions on a diagnostic and prognostic mode.

It is especially suitable for urban environment due to the fact that the 2-D grid scale on the ground surface is completely independent from the 3-D grid scale of modelling domain in the air. This allows a quite detailed description of the ground and its land uses "ignoring" computation restrictions coming from the size of the 3-D air domain.

The DETRACT consists of the following modules:

1. The Topography and Land Use Pre-processors DELTA(mesoscale) and DELTA_B(local) that prepare the necessary ground related input data for the other modules.
2. The illumination module DELTA/HELIOS indicating during one day cycle with 15-min resolution time which ground surfaces are shadowed based on the day of the year, the time of the day and the surrounding topography.
3. The Meteorological Pre-processor FILMAKER permitting to generate a complete set of meteorological data within the calculation grid based on scattered observation or forecasting data inside or even outside the grid.
4. The diagnostic module ADREA-diagn generating mass consistent wind field by correcting properly due to topography the FILMAKER or any other larger scale wind field.
5. The prognostic module ADREA-I performing small to medium scale atmospheric calculations under any atmospheric stability conditions. It is a 3-D non-hydrostatic fully compressible code utilizing the conservation laws of mass, momentum and energy. The closure scheme is based on the eddy viscosity/diffusivity concept and it is obtained through the utilization of the one equation (default) or two-equation turbulence model. The model takes into account air /ground energy and mass interactions including solar radiation and forest fire heat input.
6. The 3-D Dispersion Eulerian Model ADREA-D for passive dispersion solving the prognostic pollutant mass conservation equations separately at the gas phase and the liquid phase of the moist atmosphere. The model allows for 3-D variability of wet scavenging and deposition.
7. The 3-D Dispersion Eulerian Model ADREA/UAM for chemical substances utilizing the EPA-UAM photochemical model (33 substances) and the ADREA wind field.
8. The 3-D Langrangian Particle Model DIPCOT for passive pollutants and point sources