To enhance our understanding of the carbon cycle in the Arctic Ocean, comprehensive observational data are crucial, including measurements from the underlying ice water. This study proposed a practical method for calibrating pCO2 sensor using measured dissolved inorganic carbon and total alkalinity. Our findings suggested the minimum number of bottle samples needed for calibration to ensure 1% accuracy. Additionally, we identified the significant role of a decrease in dissolved inorganic carbon due to photosynthesis and the increase in buffer capacity of the seawater from the release of excess alkalinity by sea ice in regulating pCO2. The mean air–sea CO2 fluxes were −48.9 ± 44.6, −7.3 ± 14.6, and −1.4 ± 2.8 mmol m−2 d−1 in the southern Chukchi Sea, northern Chukchi Sea, and northern East Siberian Sea, respectively. We found a robust negative correlation between the flux and sea ice concentration in the Arctic Sea ice regions.

中文翻译：

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2022 年夏季观测中北冰洋冰层覆盖区域的 pCO2 变化


为了加深我们对北冰洋碳循环的了解，全面的观测数据至关重要，包括底层冰水的测量数据。本研究提出了一种使用测量的溶解无机碳和总碱度校准 pCO2 传感器的实用方法。我们的研究结果表明，为确保 1% 的准确度，校准所需的瓶子样本数量最少。此外，我们还发现光合作用导致的溶解无机碳减少以及海冰释放过量碱度导致海水缓冲能力增加在调节 pCO2 方面发挥着重要作用。楚科奇海南部、楚科奇海北部和东西伯利亚海北部的平均海气 CO2 通量分别为 -48.9 ± 44.6、-7.3 ± 14.6 和 -1.4 ± 2.8 mmol m−2 d−1。我们发现北极海冰区域的通量和海冰浓度之间存在很强的负相关性。