Radiocarbon in dissolved organic carbon of the Atlantic Ocean

Marine dissolved organic carbon (DOC) is produced in the surface ocean though its radiocarbon (14C) age in the deep ocean is thousands of years old. Here we show that ≥10% of the DOC in the deep North Atlantic is of postbomb origin and that the 14C age of the prebomb DOC is ≥4900 14C year, ~900 14C year older than previous estimates. We report 14C ages of DOC in the deep South Atlantic that are intermediate between values in the North Atlantic and the Southern Ocean. Finally, we conclude that prebomb DOC 14C ages are older and a portion of deep DOC is more dynamic than previously reported. Key Points More than 10% of DOC in the deep North Atlantic contains bomb 14C DOC decreases in concentration and increases in 14C age along the deep ocean conveyor DOC in the deep ocean is surprisingly dynamic both temporally and spatially