Computing inventories of anthropogenic CO2 in the eastern subpolar North Atlantic using OVIDE data

The highest anthropogenic CO2 (Cant) inventories of all the oceans are found in the subpolar North Atlantic (SPNA). The OVIDE section crosses the SPNA from Greenland to Portugal and is repeated biennially since 2002. Therefore, OVIDE data allow evaluating the evolution of inventories of anthropogenic CO2 (Cant) in the SPNA. This oceanic region is known to host water formation and ventilation processes that change the water mass volumetric census year by year. Changes in the volumetric census cause differences in the Cant inventory estimates (Pérez et al., 2008). Consequently, Pérez et al. (2010) proposed a method for computing Cant inventory in the SPNA taking into account the volumetric census variability and a bathymetric adjustment. This method has been recently revised. The initial methodology and the recent improvements are detailed in this report.