Dissolved inorganic carbon and total alkalinity of seawater samples during RV POLARSTERN expedition PS122 - MOSAiC.

Discrete seawater samples for dissolved inorganic carbon (DIC) and total alkalinity (TA) were collected from the Polarstern (https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_321) and Ocean City (https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_935) CTD/Rosette systems during the Multidisciplinary drifting observatory for the study of Arctic Climate (MOSAiC) expedition, 20 September 2019 - 14 October 2020. Following Dickson et al. (2007), seawater samples were collected between 30 October 2019 and 28 September 2020 in borosilicate (3.3) bottles (250 ml), fixed with saturated mercuric chloride (HgCl2) solution (100 maicro l), capped with greased (Apiezon L) ground glass stoppers secured by insulating tape, and stored dark +4 degree C until post-cruise analysis at the Institute of Marine Research (IMR, Norway), University of East Anglia (UEA, UK), and Hokkaido University (Japan). DIC was determined by coulometric titration (Johnson et al., 1985) using a Versatile INstrument for the Determination of Total inorganic carbon and titration Alkalinity (VINDTA 3C, Marianda, Germany) at UEA, a VINDTA 3D at IMR, and a custom-built extraction system at Hokkaido University (Ono et al., 1998). TA was determined by potentiometric titration using a VINDTA 3C at UEA, a Versatile Instrument for the Determination of Titration Alkalinity (VINDTA 3S, Marianda, Germany) at IMR, and a TA analyzer ATT-05 (Kimoto Electric Co., Ltd., Japan) at Hokkaido University. The accuracy for both DIC and TA was set at IMR and UEA by routine analysis of certified reference material (CRM batch #182, #191) distributed by A. G. Dickson (Scripps Institution of Oceanography, La Jolla, CA, USA). Reference materials (Batch AR and AU; KANSO Technos Co., Ltd., Osaka, Japan), traceable to the Scripps CO2 CRM, were used at Hokkaido University. Analytical precision for DIC and TA content is < +-2 micro mol/kg and < +-2 micro mol/kg, respectively, based on CRM replicates. Based on secondary quality control (Jutterstrom et al., 2010; Tanhua et al., 2010), DIC and TA were adjusted by -8 micro mol/kg and -23 micro mol/kg, respectively, for events PS122/1_7-49, PS122/1_8-46, PS122/1_9-50, and PS122/1_10-45. Data quality is indicated by flags following the consolidated WOCE system of Jiang et al. (2022).2019年9月20日至2020年10月14日的北极气候多学科漂移观测站（Multidisciplinary drifting observatory for the study of Arctic Climate, MOSAiC）科考航次中，研究人员依托“极星号”（Polarstern）与大洋城（Ocean City）的温盐深（CTD）/罗塞特（Rosette）采水系统，采集了溶解无机碳（dissolved inorganic carbon, DIC）与总碱度（total alkalinity, TA）的离散海水样本，样本相关检索链接为：https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_321 以及 https://sensor.awi.de/?site=search&q=vessel:polarstern:ctd_sbe9plus_935。 遵循Dickson等（2007）的实验规范，本次采样时段为2019年10月30日至2020年9月28日，采用硼硅酸盐（3.3型）250ml采水瓶收集海水样本，加入100微升饱和氯化汞（HgCl₂）溶液进行固定，使用涂抹阿皮松L（Apiezon L）真空油脂的磨砂玻璃塞密封，并以绝缘胶带加固，全程避光储存于4℃环境中，直至航次结束后，分别在挪威海洋研究所（Institute of Marine Research, IMR）、英国东英吉利大学（University of East Anglia, UEA）以及日本北海道大学开展航后分析。 溶解无机碳（DIC）的测定方面，英国东英吉利大学（UEA）采用德国Marianda公司生产的总无机碳与滴定总碱度多功能测定仪（Versatile INstrument for the Determination of Total inorganic carbon and titration Alkalinity, VINDTA 3C），依据Johnson等（1985）提出的库仑滴定法完成检测；挪威海洋研究所（IMR）使用VINDTA 3D进行测定；日本北海道大学则采用Ono等（1998）报道的自主搭建萃取系统开展分析。 总碱度（TA）的测定方面，英国东英吉利大学（UEA）同样使用VINDTA 3C通过电位滴定法完成检测；挪威海洋研究所（IMR）使用德国Marianda公司生产的滴定总碱度多功能测定仪（Versatile Instrument for the Determination of Titration Alkalinity, VINDTA 3S）；日本北海道大学则采用日本木村电机株式会社（Kimoto Electric Co., Ltd.）生产的TA分析仪ATT-05进行测定。 准确度质控方面，挪威海洋研究所（IMR）与英国东英吉利大学（UEA）通过常规分析由A.G. Dickson（美国加州拉霍亚斯克里普斯海洋研究所）分发的标准参考物质（CRM批次#182、#191），来设定DIC与TA的分析准确度；日本北海道大学则使用可溯源至斯克里普斯CO₂标准参考物质的参考物质（AR与AU批次，日本大阪KANSO Technos株式会社生产）开展质控。基于标准参考物质的平行测定结果，DIC与TA的分析精密度分别优于±2微摩尔/千克。 依据Jutterstrom等（2010）与Tanhua等（2010）提出的二级质控标准，针对PS122/1_7-49、PS122/1_8-46、PS122/1_9-50以及PS122/1_10-45这四个批次的样本，分别将DIC与TA的测定值校正-8微摩尔/千克与-23微摩尔/千克。 本数据集的数据质量采用Jiang等（2022）整合的世界海洋环流实验（WOCE）标识体系进行标注。