Influence of air–sea fluxes on chlorine isotopic composition of ocean water: Implications for constancy in δ37Cl—A statistical inference

The behaviors of chlorine isotopes in relation to air–sea flux variables have been investigated through multivariate statistical analyses (MSA). The MSA technique provides an approach to reduce the data set and was applied to a set of 7 air–sea flux variables to supplement and describe the variation in chlorine isotopic compositions (δ37Cl) of ocean water.The variation in δ37Cl values of surface ocean water from 51 stations in 4 major world oceans—the Pacific, Atlantic, Indian and the Southern Ocean has been observed from − 0.76 to + 0.74‰ (av. 0.039 ± 0.04‰). The observed δ37Cl values show basic homogeneity and indicate that the air–sea fluxes act differently in different oceanic regions and help to maintain the balance between δ37Cl values of the world oceans. The study showed that it is possible to model the behavior of chlorine isotopes to the extent of 38–73% for different geographical regions. The models offered here are purely statistical in nature; however, the relationships uncovered by these models extend our understanding of the constancy in δ37Cl of ocean water in relation to air–sea flux variables.