Fraile IArrizabalaga HJEROEN GROENEVELDKölling MSantos M.NMacías DAddis PDettman D.LKarakulak SDeguara SRooker J.R.2022-11-112022-11-11201609247963https://www.scopus.com/inward/record.uri?eid=2-s2.0-84958212326&doi=10.1016%2fj.jmarsys.2015.12.012&partnerID=40&md5=362ac40e2539d82c04de5f37baff11f2https://scholars.lib.ntu.edu.tw/handle/123456789/624766Otoliths of Atlantic bluefin tuna (Thunnus thynnus) collected from the Mediterranean Sea and North Atlantic Ocean were analyzed to evaluate changes in the seawater isotopic composition over time. We report an annual otolith δ13C record that documents the magnitude of the δ13C depletion in the Mediterranean Sea between 1989 and 2010. Atlantic bluefin tuna in our sample (n = 632) ranged from 1 to 22 years, and otolith material corresponding to the first year of life (back-calculated birth year) was used to reconstruct seawater isotopic composition. Otolith δ18O remained relatively stable between 1989 and 2010, whereas a statistically significant decrease in δ13C was detected across the time interval investigated, with a rate of decline of 0.05‰ yr-1 (-0.94‰ depletion throughout the recorded period). The depletion in otolith δ13C over time was associated with the oceanic uptake of anthropogenically derived CO2.. © 2016 Elsevier B.V.CO2 emission; Mediterranean Sea; Suess effect; δ13C and δ18O[SDGs]SDG14Isotopes; Seawater; Anthropogenic CO; Isotopic composition; Mediterranean sea; North Atlantic Ocean; Oceanic uptake; Suess effect; Thunnus thynnus; Time interval; Carbon dioxide; Thunnus thynnusjournal article10.1016/j.jmarsys.2015.12.0122-s2.0-84958212326