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To examine seasonal and regional variabilities in metabolic status and the coupling of net community production (NCP) and air‐sea CO2 fluxes in the western Arctic Ocean, we collected underway measurements of surface O2/Ar and partial pressure of CO2 (pCO2) in the summers of 2016 and 2018. With a box‐model, we demonstrate that accounting for local sea ice history (in addition to wind history) is important in estimating NCP from biological oxygen saturation (Δ(O2/Ar)) in polar regions. Incorporating this sea ice history correction, we found that most of the western Arctic exhibited positive Δ(O2/Ar) and negative pCO2 saturation, Δ(pCO2), indicative of net autotrophy but with the relationship between the two parameters varying regionally. In the heavy ice‐covered areas, where air‐sea gas exchange was suppressed, even minor NCP resulted in relatively high Δ(O2/Ar) and low pCO2 in water due to limited gas exchange. Within the marginal ice zone, NCP and CO2 flux magnitudes were strongly inversely correlated, suggesting an air to sea CO2 flux induced primarily by biological CO2 removal from surface waters. Within ice‐free waters, the coupling of NCP and CO2 flux varied according to nutrient supply. In the oligotrophic Canada Basin, NCP and CO2 flux were both small, controlled mainly by air‐sea gas exchange. On the nutrient‐rich Chukchi Shelf, NCP was strong, resulting in great O2 release and CO2 uptake. This regional overview of NCP and CO2 flux in the western Arctic Ocean, in its various stages of ice‐melt and nutrient status, provides useful insight into the possible biogeochemical evolution of rapidly changing polar oceans. Key Points: Accounting for the local sea ice history (in addition to wind history) is important in estimating net community production from Δ(O2/Ar)Coupling of sea surface Δ(O2/Ar) and Δ(pCO2) and related NCP and CO2 flux vary regionally as sea ice cover changesPacific Water greatly affects the regional NCP and CO2 flux in the western Arctic Ocean in summer [ABSTRACT FROM AUTHOR]