Climatology of Dust Deposition in the Adriatic Sea; a Possible Impact on Marine Production

Atmospheric mineral dust deposition plays an important role in providing nutrients to marine ecosystems. In this study, the climatology of dust deposition in the Adriatic Sea area was determined for the first time based on Modern-Era Retrospective Analysis for Research and Applications, version 2 reanalysis from 1989 to 2019. The annual cycle of deposition exhibits two maxima: a stronger maxima in March-April and a weaker maxima in November. Wet deposition is a dominant process with a relative contribution to overall deposition from 67.35% to 88.53%. Deposition hot spots are along the Montenegrin coast and Otrant. The average contribution of dust deposition events (DDEs) is 16.5% (60.2 dy yr(-1)), with the strongest deposition during 1999-2009 and a positive trend in deposited mass during the study period. The effect of dust deposition on primary production is observed by a high level of oxygen saturation up to 250% (usually it is lower, up to 150%) in the stratified middle water layer (5-8 m) of the central Adriatic marine system (Rogoznica Lake) during an intense wet deposition episode. Such extreme values of oxygen saturation can be taken as an indication of biological activity related to an increase in phytoplankton abundance and activity, diatoms in particular.