Keywords: Alkalinity, total; Aragonite saturation state; Baltic Sea; Bathycoccus sp.; Bay of Kiel, Baltic Sea; Bicarbonate ion; BIOACID; Biological Impacts of Ocean Acidification; Biomass/Abundance/Elemental composition; Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Cell biovolume; Cell density; Cell size; Cerataulina pelagica; Cerataulina planktonica; Ceratium fusus; Ceratium lineatum; Ceratium tripos; Chaetoceros curvisetus; Coast and continental shelf; Community composition and diversity; Coscinodiscus sp.; Cylindrotheca closterium; Dactyliosolen fragilissimus; Dactyliosolen sp.; DATE/TIME; Day of experiment; Diameter; Ditylum brightwellii; Entire community; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Guinardia flaccida; Guinardia sp.; Identification; Kiel_Bight; Laboratory experiment; Mesocosm or benthocosm; Name; OA-ICC; Ocean Acidification International Coordination Centre; Ostreococcus sp.; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Proboscia alata; Prorocentrum micans; Pseudonitzschia sp.; Registration number of species; Rhizosolenia setigera; Rhizosolenia sp.; Salinity; Sample code/label; Skeletonema marinoi; Skeletonema sp.; Species; Stauroneis constricta; Synechococcus sp.; Teleaulax amphioxeia; Temperate; Temperature; Temperature, water; Thalassionema sp.; Thalassiosira nordenskioldii; Thalassiosira sp.; Thalssionema nitzschioides; Treatment; Type; Uniform resource locator/link to reference