Total dissolved inorganic carbon and total alkalinity from CTD casts at stations between 54°S, 89°W and 60°S, 89°W on CUSTARD cruise DY111.

This dataset contains measurements of total dissolved inorganic carbon (DIC) and total alkalinity (TA). Data were collected along longitude 89°W at 7 different repeat stations: OOI at 54°S, TN at 57°S, TS at 60°S, Tran_1 at 55°S, Tran_2 at 56°S, Tran_3 at 58°S, and Tran_4 at 59°S. Data collection took place on board RRS Discovery cruise DY111 between the 4th of December 2019 and the 6th of January 2020. Data were obtained from 23 stainless steel and 1 titanium CTD casts. Samples were collected in 250 mL borosilicate bottles and stored until analysis, usually no later than 2 days. Samples were taken directly from the Niskin bottles, using Tygon tubing. Concentration of total dissolved inorganic carbon (DIC) per unit mass of the water body was measured by coulometry (Johnson et al., 1993; DOE, 1994). Total alkalinity (TA) per unit mass of the water body was measured by titration using curve fits along modified Gran plots (Gran, 1952; Bradshaw 1981; Dickson, 1993). Analysis was performed with two integrated systems: the VINDTA (Versatile Instrument for Determination of Titration Alkalinity, MARIANDA: Marine Analytics and Data, Kiel, Germany) instruments. These data were collected to examine seasonal changes in biogeochemistry in the Southern Ocean across the spring bloom as part of the Carbon Uptake and Seasonal Traits in Antarctic Remineralisation Depth (CUSTARD) project (NERC grants NE/P021247/1 and NE/P021263/1).

本数据集包含总溶解无机碳（total dissolved inorganic carbon, DIC）和总碱度（total alkalinity, TA）的测量数据。数据沿西经89°在7个不同的重复观测站采集：OOI站（南纬54°）、TN站（南纬57°）、TS站（南纬60°）、Tran_1站（南纬55°）、Tran_2站（南纬56°）、Tran_3站（南纬58°）及Tran_4站（南纬59°）。数据采集于2019年12月4日至2020年1月6日期间，在RRS Discovery号科考船DY111航次中进行。数据通过23次不锈钢温盐深仪（CTD）投放和1次钛合金温盐深仪（CTD）投放获取。样本采集于250毫升硼硅酸盐瓶中，储存至分析前（通常不超过2天），并通过Tygon管直接从尼斯金瓶（Niskin bottle）中提取。水体单位质量的总溶解无机碳（DIC）浓度采用库仑法测定（Johnson等，1993；DOE，1994）；总碱度（TA）浓度则通过滴定法测定，结合修正格兰图（modified Gran plot）的曲线拟合方法（Gran，1952；Bradshaw，1981；Dickson，1993）。分析工作借助两套集成系统完成：VINDTA仪器（多功能滴定碱度测定仪，Versatile Instrument for Determination of Titration Alkalinity，由德国基尔海洋分析与数据公司MARIANDA生产）。这些数据旨在探究南大洋春季水华期间生物地球化学的季节变化，是南极再矿化深度碳吸收与季节特征项目（Carbon Uptake and Seasonal Traits in Antarctic Remineralisation Depth, CUSTARD）的核心组成部分，该项目由英国自然环境研究理事会（NERC）资助（项目编号NE/P021247/1和NE/P021263/1）。