A study was conducted to compare the δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) scales used by four laboratories engaged in atmospheric δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) measurements. These laboratories are the Research Institute for Environmental Management Technology, Advanced Industrial Science and Technology (EMRI/AIST); the National Institute for Environmental Studies (NIES); Tohoku University (TU); and Scripps Institution of Oceanography (SIO). Therefore, five high-precision standard mixtures for the O₂ molar fraction gravimetrically prepared by the National Metrology Institute of Japan, AIST (NMIJ/AIST) with a standard uncertainty of less than 5 per meg (0.001 ‰) were used as round-robin standard mixtures. EMRI/AIST, NIES, TU, and SIO reported the analyzed values of the standard mixtures on their own δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) scales, and the values were compared with the δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) values gravimetrically determined by NMIJ/AIST (the NMIJ/AIST scale). The δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) temporal drift in the five standard mixtures during the intercomparison experiment from May 2017 to March 2020 was corrected based on the δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) values analyzed before and after the laboratory measurements by EMRI/AIST. The scales are compared based on offsets in zero and span. The relative span offsets of EMRI/AIST, TU, NIES, and SIO scales against the NMIJ/AIST scale were $-\mathrm{0.11}\mathit{\%}\pm \mathrm{0.10}\mathit{\%}$, $-\mathrm{0.10}\mathit{\%}\pm \mathrm{0.13}\mathit{\%}$, 3.39 %±0.13 %, and 0.93 %±0.10 %, respectively. The largest offset corresponded to a 0.30 Pg yr⁻¹ decrease and increase in global estimates for land biospheric and oceanic CO₂ uptakes based on trends in atmospheric CO₂ and δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$). The deviations in the measured δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) values on the laboratory scales from the NMIJ/AIST scale are 65.8±2.2, 425.7±3.1, 404.5±3.0, and 596.4±2.4 per meg for EMRI/AIST, TU, NIES, and SIO, respectively. The difference between atmospheric δ(${\mathrm{O}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) values observed at Hateruma Island (HAT; 24.05^∘ N, 123.81^∘ E), Japan, by EMRI/AIST and NIES were reduced from $-\mathrm{329.3}\pm \mathrm{6.9}$ to $-\mathrm{6.6}\pm \mathrm{6.8}$ per meg by converting their scales to the NMIJ/AIST scale.

中文翻译：

---

AIST、NIES、TU 和 SIO 之间的 O2 ∕ N2 比率量表的比对，基于使用重量标准混合物的循环练习

进行了一项研究来比较δ (${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) 四个从事大气δ 的实验室使用的标度(${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$） 测量。这些实验室是环境管理技术研究所、先进工业科学与技术研究所（EMRI/AIST）；国家环境研究所（NIES）；东北大学（TU）；和斯克里普斯海洋学研究所 (SIO)。因此，使用由日本国家计量院 AIST (NMIJ/AIST) 重量法制备的O ₂摩尔分数的五种高精度标准混合物， 标准不确定度小于 5 每兆 (0.001 ‰) 用作循环法标准混合物。EMRI/AIST、NIES、TU 和 SIO 报告了标准混合物对其自身δ的分析值（${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) 尺度，并将这些值与δ (${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) 值由 NMIJ/AIST（NMIJ/AIST 标度）按重量测定。该δ（${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) 根据δ (${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) 通过 EMRI/AIST 在实验室测量之前和之后分析的值。比例基于零和跨度中的偏移进行比较。EMRI/AIST、TU、NIES 和 SIO 量表相对于 NMIJ/AIST 量表的相对跨度偏移为$——\mathrm{0.11}\mathit{\%}\pm \mathrm{0.10}\mathit{\%}$, $——\mathrm{0.10}\mathit{\%}\pm \mathrm{0.13}\mathit{\%}$、 3.39  % ±0.13  %和0.93  % ±0.10  %。最大的偏移对应于基于大气CO ₂和δ趋势的陆地生物圈和海洋CO ₂吸收全球估计值减少和增加0.30  Pg yr ^-1（${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$）。测量值的偏差δ (${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$从NMIJ / AIST规模实验室级）的值是65.8±2.2，425.7±3.1，404.5±3.0，和596.4±2.4分别为每微克为EMRI / AIST，TU，NIES，和SIO。大气δ (${\mathrm{哦}}_{\mathrm{2}}/{\mathrm{N}}_{\mathrm{2}}$) 在日本波照间岛 (HAT; 24.05 ^∘  N, 123.81 ^∘  E)观察到的值从 EMRI/AIST 和 NIES 减少到$——\mathrm{329.3}\pm \mathrm{6.9}$ 到 $——\mathrm{6.6}\pm \mathrm{6.8}$ 每兆通过将其比例转换为 NMIJ/AIST 比例。