Abstract Less than three decades ago only a small fraction of the Arctic Ocean (AO) was ice free and then only for short periods. The ice cover kept sea surface pCO2 at levels lower relative to other ocean basins that have been exposed year round to ever increasing atmospheric levels. In this study, we evaluate sea surface pCO2 measurements collected over a 6‐year period along a fixed cruise track in the Canada Basin. The measurements show that mean pCO2 levels are significantly higher during low ice years. The pCO2 increase is likely driven by ocean surface heating and uptake of atmospheric CO2 with large interannual variability in the contributions of these processes. These findings suggest that increased ice‐free periods will further increase sea surface pCO2, reducing the Canada Basin's current role as a net sink of atmospheric CO2.

中文翻译：

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随着冰盖减少，北冰洋碳循环的变化

摘要 不到三年前，北冰洋 (AO) 只有一小部分是无冰的，而且只有很短的时间。冰盖使海面 pCO2 的水平低于其他常年暴露在不断增加的大气水平下的海洋盆地。在这项研究中，我们评估了 6 年间沿加拿大盆地固定巡航轨道收集的海面 pCO2 测量值。测量结果表明，在低冰年期间，平均 pCO2 水平明显更高。pCO2 的增加很可能是由海洋表面加热和大气 CO2 的吸收所驱动的，这些过程的贡献有很大的年际变化。这些发现表明，无冰期的增加将进一步增加海面 pCO2，从而降低加拿大盆地目前作为大气 CO2 净汇的作用。