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We estimated monthly air–sea CO₂ fluxes in the Arctic Ocean and its adjacent seas north of 60° N from 1997 to 2014. This was done by mapping partial pressure of CO₂ in the surface water (<i>p</i>CO_2w) using a self-organizing map (SOM) technique incorporating chlorophyll <i>a</i> concentration (Chl <i>a</i>), sea surface temperature, sea surface salinity, sea ice concentration, atmospheric CO₂ mixing ratio, and geographical position. We applied new algorithms for extracting Chl <i>a</i> from satellite remote sensing reflectance with close examination of uncertainty of the obtained Chl <i>a</i> values. The overall relationship between <i>p</i>CO_2w and Chl <i>a</i> was negative, whereas the relationship varied among seasons and regions. The addition of Chl <i>a</i> as a parameter in the SOM process enabled us to improve the estimate of <i>p</i>CO_2w, particularly via better representation of its decline in spring, which resulted from biologically mediated <i>p</i>CO_2w reduction. As a result of the inclusion of Chl <i>a</i>, the uncertainty in the CO₂ flux estimate was reduced, with a net annual Arctic Ocean CO₂ uptake of 180 ± 130 Tg C yr⁻¹. Seasonal to interannual variation in the CO₂ influx was also calculated.