Dissolved organic carbon distribution and origin in the Nordic Seas: Exchanges with the Arctic Ocean and the North Atlantic

Dissolved organic carbon (DOC) and in situ fluorescence were measured along with hydrographic parameters in the Greenland, Iceland, and Norwegian Seas (Nordic Seas). Surface (1000 m) were relatively high (∼50 μM DOC) compared with other ocean basins indicating active vertical transport of DOC in this region on decadal timescales. Based on existing vertical transport estimates and 15 μM of semilabile DOC we calculated an annual vertical net DOC export of 3.5 Tg C yr−1 in the Greenland Sea and about 36 Tg C yr−1 for the entire Arctic Mediterranean Sea (AMS) including the Greenland‐Scotland Ridge overflow. It appears that physical processes play a determining role for the distribution of DOC in the AMS.