An in situ measurement system was developed for continuous observations of the mole fractions of atmospheric oxygen (defined as δ(O₂/N₂)) and carbon dioxide (CO₂) and the continuous observation was conducted onboard the research vessel SHIRASE 5003 during its voyage between Australia and Syowa Station, Antarctica, in 2017–2018. The CO₂ variation was low with respect to that of δ(O₂/N₂) in the Southern Ocean, suggesting that the land biospheric and fossil-fuel derived CO₂ and O₂ emissions negligibly influenced the observations. Therefore, the observed significant variations in the atmospheric O₂/N₂ can be attributed to the atmosphere-ocean gas exchange. During the southbound voyage in December 2017, we observed large spatial variations in δ(O₂/N₂) due to marine biological production on the western side of the cruise track. Oceanic O₂ fluxes based on a simple model and atmospheric δ(O₂/N₂) variability were consistent with past oceanic observations. No clear longitudinal gradient in δ(O₂/N₂) was observed at latitudes toward south of 60° S in December 2017 and February–March 2018. However, local δ(O₂/N₂) maxima were observed in regions with active marine biological production in December 2017. These observations indicate that local O₂ fluxes can also modify the spatial distribution of atmospheric δ(O₂/N₂) in the Southern Ocean.

为连续观测大气氧（定义为 δ(O ₂ /N ₂ )）和二氧化碳 (CO ₂ )的摩尔分数而开发了原位测量系统，并在研究船 SHIRASE 5003 上进行了连续观测。 2017-2018 年澳大利亚和南极洲 Syowa 站之间的航行。CO ₂变化相对于南大洋的δ(O ₂ /N ₂ )变化较小，表明陆地生物圈和化石燃料衍生的CO ₂和O ₂排放对观测的影响可以忽略不计。因此，观测到的大气 O ₂ /N 的显着变化₂可归因于大气-海洋气体交换。在 2017 年 12 月的南行航行中，由于巡航轨道西侧的海洋生物生产，我们观察到 δ(O ₂ /N ₂ ) 的巨大空间变化。基于简单模型的海洋 O ₂通量和大气 δ(O ₂ /N ₂ ) 变异性与过去的海洋观测结果一致。2017 年 12 月和 2018 年 2 月至 2018 年 3 月，在南纬 60°以南的纬度未观察到明显的 δ(O ₂ /N ₂ )纵向梯度。然而，局部 δ(O ₂ /N ₂) 最大值于 2017 年 12 月在海洋生物生产活跃的地区观测到。这些观测结果表明，局部 O ₂通量也可以改变南大洋大气 δ(O ₂ /N ₂ )的空间分布。