Study of ozone transport at Mt. Cimone

Mt. Cimone, the highest peak in Italy's north-central Apennines, divides two distinct climatic regions: the continentally temperate Po Valley to the north and the Mediterranean Basin to the south. It is considered a nonpolluted site, and the Italian Meteorological Service Observatory atop it, which is part of the WMO BAPMoN for the measurement of CO 2 , turbidity, and suspended particulate matter, has been continuously monitoring surface ozone since March 1991 together with the FISBAT Insititute. The present, preliminary study of ozone transport episodes indicates that the air masses reaching Mt. Cimone exhibit low surface-ozone concentrations under certain weather conditions, i.e. the arrival of dust-laden air from the Sahara area or in concomitance with particular low-pressure systems.