7Be aerosols and their deposition on the sea: a possible method to estimate trace metals deposition on the sea

The activity size distributions of 7Be aerosols in different size fractions (<0.39 μm, 0.39–0.69 μm, 0.69–1.3 μm, 1.3–2.1 μm, 2.1–4.2 μm, 4.2–10.2 μm and >10.2 μm) were determined at the city of Thessaloniki, Greece, Eastern Mediterranean. The Activity Median Aerodynamic Diameter (AMAD) values ranged from 0.58 to 1.22 μm while more of the 80% of the 7Be activity was associated with particles smaller than 1.3 μm. Sea salt aerosol particles were defined in a small size range, lower than 0.39 μm. Field measurements at a coastal location allow the estimation of 7Be deposition on the sea. Since the 7Be aerosol particles were mainly below 1 μm, scavenging by precipitation was the main process depositing 7Be on the sea. Acting as an excellent tracer, 7Be could be used for determination of the deposition of the trace metals on the sea, since they are expected to be deposited at similar rate by wet and dry deposition processes as the 7Be.

► The 7Be activities are anticorrelated with AMAD values.
► 7Be AMAD values ranged from 0.58 to 1.22 μm.
► Trace metals are expected to deposited on the sea with similar rates as the 7Be.