RV TANGAROA Marine Science Cruise TA1302 (NIWA cruise tan1302) - ship-based CTD data

Oceanographic measurements were collected aboard New Zealand’s National Institute for Water and Atmospheric Research (NIWA) research vessel RV Tangaroa, cruise ta1302 (i.e. NIWA cruise tan1302), from 3rd February to 13th March 2013, sailing from and returning to Wellington. The cruise commenced with a series of stations at the southern end of CLIVAR/WOCE meridional section SR3, followed by work around and offshore of the former Mertz Glacier ice tongue and the Mertz Depression. A series of stations were then taken along 150E and CLIVAR/WOCE zonal section S4, followed by a series of stations on the Campbell Plateau on the transit back to New Zealand. Details of all programs on the cruise, including lowered ADCP data, carbon sampling, geological coring and grabs, bottom camera footage, multibeam data, Argo float deployments and cruise participants, can be found in the voyage report (“RV Tangaroa Voyage Report, Tan1302 – Mertz Polynya Voyage”, unpublished NIWA report, authored by voyage participants). This report discusses the oceanographic data from CTD operations on the cruise.

The original primary aim of the cruise was recovery and redeployment of an array of Australian (ACECRC) and French (LOCEAN) moorings in the Mertz region, along with CTD data collection on the shelf. Sea ice cover prevented access by Tangaroa (for the most part) to the shelf, and to any of the mooring sites, and so a secondary project was undertaken - collecting CTD’s on the slope and in canyons offshore of the sea ice.

A total of 86 CTD vertical profile stations were taken on the cruise, most to within 12 metres of the bottom. Over 1400 Niskin bottle water samples were collected for the measurement of salinity, dissolved oxygen, nutrients (silicate and nitrate+nitrite), dissolved inorganic carbon (i.e. TCO2), alkalinity, and isotopes (oxygen, hydrogen and carbon), using a 24 bottle rosette sampler. Full depth current profiles were collected by an LADCP attached to the CTD package. Meteorological and water property data were collected by the array of ship's underway sensors. The vessel mounted ADCP, rigged to a pole in the ship’s moonpool, was lost on the transit south. This report describes the processing/calibration of the CTD data, and details the data quality.

本数据集的海洋学测量数据采集于新西兰水与大气研究所（National Institute for Water and Atmospheric Research, NIWA）的科考船"Tangaroa"号（RV Tangaroa），航次编号为ta1302（即NIWA航次tan1302），采集时段为2013年2月3日至2013年3月13日，航次从惠灵顿出发并最终返回惠灵顿。本次航次首先在全球气候变率与可预报性计划/世界海洋环流实验（CLIVAR/WOCE）经向断面SR3的南端布设了一系列观测站位，随后在原默茨冰川冰舌及默茨凹陷周边及近海开展作业。科考队随后沿150°E经线以及CLIVAR/WOCE纬向断面S4布设了一系列观测站位，并在返航新西兰的途中于坎贝尔高原（Campbell Plateau）开展站位观测。本航次所有科考项目的详细信息，包括下放式声学多普勒流速剖面仪（lowered ADCP）数据、碳循环采样、地质岩芯取样与采泥器采样、海底摄像资料、多波束测深数据、Argo浮标（Argo float）布放以及航次参与人员信息，均可查阅本次航次报告《"Tangaroa"号科考船航次报告：Tan1302——默茨冰间湖航次》（*RV Tangaroa Voyage Report, Tan1302 – Mertz Polynya Voyage*，未公开的NIWA报告，由航次参与人员编写）。本报告聚焦本次航次温盐深仪（Conductivity-Temperature-Depth, CTD）作业获取的海洋学数据。

本次航次的首要目标是回收并重新布设默茨海域的澳大利亚合作研究中心（Australian Cooperative Research Centre, ACECRC）与法国海洋学与气候实验室（Laboratoire d'Océanographie et du Climat: Expérimentation et Approches Numériques, LOCEAN）的潜标阵列，同时在大陆架开展CTD数据采集作业。但受海冰覆盖影响，"Tangaroa"号大部分时段无法抵达大陆架及所有潜标布设点位，因此科考队启动了次级项目：在海冰外缘的大陆坡及海底峡谷中采集CTD数据。本航次共完成86个CTD垂直剖面观测站位，绝大多数站位的观测深度接近海底，仅距海底12米以内。科考队使用24瓶式采水器架（rosette sampler）采集了超过1400个尼斯金采水器（Niskin bottle）水样，用于测定盐度、溶解氧、营养盐（硅酸盐、硝酸盐+亚硝酸盐）、溶解无机碳（即总溶解无机碳TCO2）、碱度以及同位素（氧、氢、碳）组成。通过安装在CTD总成上的下放式声学多普勒流速剖面仪（LADCP）获取了全水深海流剖面数据。船载走航传感器阵列采集了气象及海水要素数据。安装在船底沉箱井（moonpool）立柱上的船装ADCP在南行航渡过程中遗失。本报告详细阐述了CTD数据的处理与校准流程，并对数据质量进行了说明。