Atmospheric measurements results archive, Lutjewad (60.0 m), 2000-10-19–2020-05-14

This is the data supplement presented in Nguyen et al. 2021 (https://doi.org/10.5194/essd-2021-213) in which we present 20-year flask sample records of atmospheric CO2, δO2/N2 and APO from the stations Lutjewad (the Netherlands) and Mace Head (Ireland) and a 3-year record from Halley station (Antarctica), including details of the extensive calibration procedure and its stability over time. The results of our inter-comparison involving gas cylinders from various research laboratories worldwide also show that our calibration is of high quality and compatible with the internationally-recognised Scripps scale. The measurement records from Lutjewad and Mace Head show similar long-term trends during the period 2002-2018 of 2.31 ± 0.07 ppm yr-1 for CO2 and -21.2 ± 0.8 per meg yr-1 for δO2/N2 at Lutjewad, and 2.22 ± 0.04 ppm yr-1 for CO2 and -21.3 ± 0.9 per meg yr-1 for δO2/N2 at Mace Head. They also show similar δO2/N2 seasonal cycle with an amplitude of 54 ± 4 per meg at Lutjewad and 61 ± 5 per meg at Mace Head, while CO2 seasonal amplitude at Lutjewad (16.8 ± 0.5 ppm) is slightly higher than that at Mace Head (14.8 ± 0.3 ppm). We show that the observed trends and seasonal cycles are compatible with the measurements from various stations, especially the measurements from Weybourne Atmospheric Observatory (United Kingdom). However, there are remarkable differences in the progression of annual trends between the Mace Head and Lutjewad records for δO2/N2 and APO, which might in part be caused by sampling differences, but also by environmental effects, such as the North Atlantic Ocean oxygen ventilation changes to which Mace Head is more sensitive. The Halley record shows clear trends and seasonality in δO2/N2 and APO, where especially APO agrees well with the continuous measurements at Halley by the University of East Anglia, while CO2 and δO2/N2 present slight disagreements, most likely caused by small leakages during sampling. From our 2002-2018 records, we find good agreement for the global ocean sink: 2.0 ± 0.8 PgC yr-1 and 2.2 ± 0.9 PgC yr-1, based on Lutjewad and Mace Head, respectively.
Nguyen, L.N.T., Luijkx, I., Meijer, H.A.J., 2021. Two decades of flask observations of atmospheric δO2/N2, CO2, and APO at stations Lutjewad (the Netherlands) and Mace Head (Ireland) plus 3 years from Halley station (Antarctica). https://doi.org/10.18160/QQ7D-T060

本数据集为Nguyen等人于2021年发表的补充数据（https://doi.org/10.5194/essd-2021-213），其中收录了来自荷兰Lutjewad站和爱尔兰Mace Head站的20年大气CO2、δO2/N2和APO的样品记录，以及南极洲Halley站的3年记录。数据中包含了详尽的校准程序及其随时间的稳定性分析。通过对全球各研究实验室气瓶进行互相比对，我们的校准结果显示出高质量，并与国际上公认的Scripps标度相兼容。Lutjewad和Mace Head的测量记录显示了2002-2018年期间CO2的长期趋势，平均每年上升2.31 ± 0.07 ppm，δO2/N2在Lutjewad的平均每年下降21.2 ± 0.8 per meg，而在Mace Head的平均每年下降2.22 ± 0.04 ppm。它们还显示了相似的δO2/N2季节性循环，Lutjewad的振幅为54 ± 4 per meg，而Mace Head的振幅为61 ± 4 per meg，同时Lutjewad的CO2季节性振幅（16.8 ± 0.5 ppm）略高于Mace Head（14.8 ± 0.3 ppm）。我们的研究表明，观察到的趋势和季节性循环与来自各站的测量结果相吻合，特别是与英国威温伯恩大气观测站的测量结果。然而，Mace Head和Lutjewad记录中δO2/N2和APO的年度趋势进展存在显著差异，部分可能由采样差异引起，也可能由环境因素引起，例如Mace Head对北大西洋海洋氧通气变化更为敏感。Halley站的记录在δO2/N2和APO中显示出明显的趋势和季节性，尤其是APO与东安格利亚大学的连续测量结果吻合良好，而CO2和δO2/N2的轻微差异很可能是采样过程中的小泄漏所致。基于Lutjewad和Mace Head的2002-2018年记录，我们发现了全球海洋汇的良好一致性：基于Lutjewad为2.0 ± 0.8 PgC yr-1，基于Mace Head为2.2 ± 0.9 PgC yr-1。