VERTICAL PROFILES OF PARTICULATE MATTER OVER MILAN DURING WINTER 2005/2006

摘要

Vertical profiles of PM were measured directly with an OPC in the city of Milan, a polluted urban area. The measured height of mixing layer allowed making considerations about the importance of meteorological effects related to atmospheric pollution in urban areas based on experimental data. In Milan, during winter times, the mixing layer does not reach a high altitude. This behavior is the main cause of high concentrations of PM, possibly generating acute exposure to health effects. The main goal of this approach was to investigate the behavior of PM in a three-dimensional system. In this way, it was possible to have information about atmospheric dispersal conditions, evolution of mixing layer, number concentration, and size distribution that are useful to understand PM properties" change, linked to its evolution in space and time. This information showed well that large data sets of vertical profiles can be used to validate model outputs and forecasts. Tethered balloon method, providing the possibility of using gravimetric sampling techniques, was useful to perform chemical analysis with height.