Inverse anthropogenic carbon flux estimates from the PRINCE-RDS model based on the GLODAP anthropogenic carbon data set and three scenarios designed to test the sensitivity of the inverse estimates to biases associated with estimating the anthropogenic carbon from the observations (Pg C yr-1, scaled to 1995). Positive values indicate flux into the ocean. Region Name Region Number GLODAP dataset Matsumoto High C:O Low C:O Arctic Ocean 1 0.04 0.06 0.03 0.04 N. Atl. High-Lat. 2 0.09 0.10 0.07 0.10 N. Atl. Mid-Lat. 3 0.14 0.14 0.13 0.15 N. Atl. Low-Lat. 4 0.03 0.02 0.03 0.02 N. Atl. Trop. 5 0.05 0.04 0.04 0.05 S. Atl. Trop. 6 0.09 0.07 0.0 0.10 S. Atl. Low-Lat. 7 0.03 0.02 0.03 0.03 S. Atl. Mid-Lat. 8 0.05 0.04 0.03 0.06 S. Atl. High-Lat. 9 0.05 0.04 0.04 0.06 S. Ocean 10 0.29 0.29 0.27 0.33 N.W. Pac. High-Lat. 11 0.02 0.02 0.02 0.03 N.E. Pac. High-Lat. 12 0.02 0.02 0.01 0.02 N.W. Pac. Low-Lat. 13+14 0.12 0.10 0.12 0.12 N.E. Pac. Low-Lat. 15 0.02 0.02 0.02 0.02 N.W. Pac. Trop. 16 0.07 0.06 0.07 0.07 N.E. Pac. Trop. 17 0.12 0.11 0.11 0.14 S.W. Pac. Trop. 18 0.05 0.04 0.05 0.05 S.E. Pac. Trop. 19 0.11 0.09 0.08 0.13 S.W. Pac. Mid-Lat. 20+22 0.07 0.06 0.07 0.07 S.E. Pac. Mid-Lat. 21+23+24 0.01 0.01 0.01 0.01 S. Sub-Polar Pac. + Ind. 25+30 0.37 0.33 0.34 0.40 Trop. Ind. 26+27 0.14 0.12 0.12 0.15 S. Ind. Low-Lat. 28 0.06 0.05 0.06 0.06 S. Ind. High-Lat. 29 0.16 0.14 0.17 0.15 Global Total Null 2.17 1.99 2.02 2.35