A modeling system for describing mineral dust and sea salt cycles in the atmosphere

摘要

Air quality in and around airports is an important issue because of the critical physical and chemical processes that take place. In air quality modeling systems, these physical and chemical components are usually treated separately. This approach causes a loss of crucial information about atmospheric processes that evolve in a small timescale. This information is very important especially in prediction modeling systems where the spatial resolution is very fine. Hence, an on-line coupled weather and air quality modeling system would provide a more thorough simulation of these atmospheric processes. In this presentation we discuss the characteristics of the first component of the new modeling tool that is under development for this purpose. More specifically, the treatment of the natural sources of particulate matter (PM) will be discussed, and especially for mineral dust and sea salt, because of their impacts on weather, environment and aviation safety. This category of sources is considered crucial in many regions and especially for airports that are located in areas with frequent dust events, as well as those near to coastal areas. The main features of the parameterization, production, transport and transformation processes will be presented and the ability of the modeling system to describe and predict dust event features will be tested. The different parts of this development have been independently validated by comparison with available measurements and experimental data. For a first testing of the development the dust event of 16-18 April 2005 has been simulated. The agreement of the components of the wet and dry deposition processes with experimental data is satisfying. The modeled concentrations of mineral dust are in good agreement with measurements from air quality stations around Athens International Airport (AIA).