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Abstract Several methods have been developed to quantify the oceanic accumulation of anthropogenic carbon dioxide (CO₂) in response to rising atmospheric CO₂. Yet, we still lack a corresponding estimate of the changes in the total oceanic dissolved inorganic carbon (DIC). In addition to the increase in anthropogenic CO₂, changes in DIC also include alterations of natural CO₂. Once integrated globally, changes in DIC reflect the net oceanic sink for atmospheric CO₂, complementary to estimates of the air‐sea CO₂exchange based on surface measurements. Here, we extend the MOBO‐DIC machine learning approach by Keppler et al. (2020a,https://www.ncei.noaa.gov/access/metadata/landing-page/bin/iso?id=gov.noaa.nodc%3A0221526) to estimate global monthly fields of DIC at 1° resolution over the top 1,500 m from 2004 through 2019. We find that over these 16 years and extrapolated to cover the whole global ocean down to 4,000 m, the oceanic DIC pool increased close to linearly at an average rate of 3.2 ± 0.7 Pg C yr⁻¹. This trend is statistically indistinguishable from current estimates of the oceanic uptake of anthropogenic CO₂over the same period. Thus, our study implies no detectable net loss or gain of natural CO₂by the ocean, albeit the large uncertainties could be masking it. Our reconstructions suggest substantial internal redistributions of natural oceanic CO₂, with a shift from the midlatitudes to the tropics and from the surface to below ∼200 m. Such redistributions correspond with the Pacific Decadal Oscillation and the Atlantic Multidecadal Oscillation. The interannual variability of DIC is strongest in the tropical Western Pacific, consistent with the El Nio Southern Oscillation.