Atmospheric transport of desert dust toward European Seas: Model parameterisation and a simulated case

Long range transport of dust from the desert and its deposition into remote areas may significantly contribute to the local atmospheric deposition. Although the North, Baltic and Black Seas are not close to Sahara, the dust originating from Sahara is deposited in these regions, especially by precipitation, and therefore has influence on the local chemical properties of the water. A full Eulerian prognostic model for the atmospheric dust transport is described in this study. The model simulates the processes of the dust suspension from the ground, vertical turbulent mixing, horizontal and vertical advection, horizontal diffusion and dry and wet deposition. A case study of a very intense dust storm in early July 1991 is simulated to quantify the dust deposition into the sea, as it is very difficult to estimate it from the ground station measurements. The results showed that the wet deposition into North, Baltic and Black Seas was of the same order of magnitude as into the Mediterranean Sea near the Sahara desert. These short but intense episodes of a large deposition of minerals during several hours may have significant influence on the local marine ecology in those seas.