[abstract] In this paper we present the results of more than one year (from early 1996 to mid 1997) of local and regional scale optical observations of North African dust exports to the Mediterranean basin. Regional survey and monitoring of dust transport were made using Meteosat. From its observation daily mean dust optical thickness have been obtained for 1996 and 1997. The inter-annual variation is discussed. As regards to the local scale observations we have operated 2-backscatter lidar systems and one sun photometer. The derived optical parameters are the optical thickness and Angstrom exponent. The sun photometer and one of the lidar systems were used simultaneously on an urban site of Greece. Used in synergy with Meteosat we were able to identify without any doubt the optical signature of dust particles. However the results appeared to be more characteristic of a mixture of dust particles and pollution like particles. De-coupling of both effects was possible when simultaneous lidar and sun photometer measurements were available. Lidar systems have given access to the vertical structure of the dust transport. It appeared to be made in most cases of several distinct layers. Investigations including back-trajectories and dust uptake sources identification using Meteosat IR observations have led us to the conclusion that the multi-layering of the transport is linked to the advection above the measurement sites of dust loaded air masses from different origins.
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