Spatial and temporal trends of anthropogenic carbon storage in typical marginal seas along the Asia continent in the northern hemisphere

Global climate change is an indisputable fact, and anthropogenic disturbances are the likely driving mechanisms; moreover, marginal seas tend to respond faster than the global ocean. In this study, the transit time distribution method was used to estimate the anthropogenic carbon (Cant) in the typical marginal seas along the west side of North Pacific Ocean and the Arctic Ocean. From the South China Sea (SCS) to the Arctic Ocean (AO), the range of Cant storage gradually increased with latitude. The maximum and minimum rates of ~0.6 mol C·m−2·yr−1, and ~0.2 mol C·m−2·yr−1 were seen in the AO and SCS, respectively. In the short term, warming and decline of ice cover may promote the transfer of excess CO2 from the atmosphere to the water interior; but on a longer time scale, a positive feedback (i.e., reduced CO2 absorption) may occur due to warming. Accordingly, the AO will likely no longer be a CO2 sink in the future when the sea ice disappears completely.