Inorganic Carbon in High Latitude Estuary-Fjord system, Cumberland Sound on Baffin Island, Eastern Canadian Arctic

Rapidly changing conditions in the Arctic can have a significant impact on biogeochemical cycles and these changes can be particularly critical in high latitude estuary-fjord systems with abundant freshwater sources. This study provides a first look into the inorganic carbon system and in Cumberland Sound in the east coast of Baffin Island, Nunavut. Our results show that Cumberland Sound was undersaturated during the ice-free conditions in August 2011 with surface water pCO₂ between 260 and 300 μatm. DIC and TA values in the upper 40 m ranged between 1779 and 1966 μmol kg^-1 and 1922 and 2140 μmol kg^-1, respectively. Lowest values were observed at the surface associated with fresh water input. The pH/Aragonite saturation () state ranges from 8.16/1.9 in the surface to 8.04/1.4 in the subsurface waters, respectively. The relationships between TA, , and salinity suggest high meteoric water input (MV) in the surface waters of Cumberland Sound in comparison to the connected Baffin Bay and Labrador Sea. Data show decreasing TA and with increasing freshwater fraction and suggest that Cumberland Sound waters would become undersaturated at MV > 39%. Our results contribute to a very limited set of inorganic carbon data in high latitude estuary-fjord systems.