In the present study, we investigated from July 2010 to April 2012 the effects of in situ exposure to different pH levels (range pHTS 7.4–8.1) and seasonal temperatures (range 15.5–25.6 °C) on the mortality and net calcification rates of Mediterranean scleractinian corals transplanted near a volcanic CO2 vent off Panarea Island (Aeolian Islands, southern Italy) which generates a pH gradient at ambient temperature. This dataset is included in the OA-ICC data compilation maintained in the framework of the IAEA Ocean Acidification International Coordination Centre (see https://oa-icc.ipsl.fr). Original data were provided by the author of the related paper (see Related to) to the OA-ICC data curator. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2024) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2024-09-02.