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A seminal study on oxygen and carbon stable isotopes in planktonic foraminifera from Arctic Ocean floor appeared in Marine Geology 20 years ago (Spielhagen and Erlenkeuser, 1994).We revisit this topic with a wealth of new data focused on the western (Amerasian) Arctic, a spotlight in the current climatic and oceanic change.Neogloboquadrina pachyderma (Np), the most abundant polar planktonic foraminiferal species, is an important tool for reconstructing surface/subsurface water changes in the Arctic.Both δ18O and δ13C of Np are influenced by complex water sources, water column structure, and foraminiferal depth habitat in the Arctic Ocean.Our data on distribution of Np stable isotopes in surface seafloor sediments confirms a shallow habitat of this species in the sea-ice covered central Arctic, especially in the Canada Basin, in relationship to a deeper halocline and/or shallow chlorophyll maximum.The associated light Np δ18O reflects the long-term storage of fresh water, possibly with contribution from brines formed during sea-ice formation.Heavy Np δ13C values in the central Arctic are likely supported by biological production at the chlorophyll maximum depth.Shoreward decrease in Np δ13C is consistent with contributions of isotopically light riverine DIC.Distribution of Np δ13C on the Chukchi Shelf reflects primary production patterns in the area.