TY - JOUR T1 - Radiocarbon Content of Dissolved Organic Carbon in the South Indian Ocean JF - Geophysical Research Letters Y1 - 2018 A1 - Bercovici, S. K. A1 - McNichol, A. P. A1 - Xu, L. A1 - Hansell, D. A. KW - dissolved organic carbon KW - indian ocean KW - radiocarbon AB - We report four profiles of the radiocarbon content of dissolved organic carbon (DOC) spanning the South Indian Ocean (SIO), ranging from the Polar Front (56°S) to the subtropics (29°S). Surface waters held mean DOC Δ14C values of −426 ± 6‰ (~4,400 14C years) at the Polar Front and DOC Δ14C values of −252 ± 22‰ (~2,000 14C years) in the subtropics. At depth, Circumpolar Deep Waters held DOC Δ14C values of −491 ± 13‰ (~5,400 years), while values in Indian Deep Water were more depleted, holding DOC Δ14C values of −503 ± 8‰ (~5,600 14C years). High‐salinity North Atlantic Deep Water intruding into the deep SIO had a distinctly less depleted DOC Δ14C value of −481 ± 8‰ (~5,100 14C years). We use multiple linear regression to assess the dynamics of DOC Δ14C values in the deep Indian Ocean, finding that their distribution is characteristic of water masses in that region. VL - 45 UR - https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2017GL076295 IS - 2 ER -