IMOS - SOOP Ocean Carbon Dioxide Data from RV Southern Surveyor voyage SS012008

This data was collected in January 2008 by the IMOS Ship of Opportunity Underway CO2 Measurement research group on RV Southern Surveyor (IMOS platform code: VLHJ) voyage SS012008.\n\nDeparted: \tHobart, Tasmania, January 11, 2008\nArrived: \tHobart, Tasmania February 01, 2008\n\nCO2 System Overview:\nThe fugacity of carbon dioxide (fCO2) in surface seawater was measured using a General Oceanics Inc. automated system (Model 8050; Pierrot et al 2009). Seawater is sprayed into an equilibration chamber and CO2 in the headspace gas equilibrates with the seawater. The headspace gas is pumped through a thermoelectric condenser followed by a nafion drying tube before flowing through a Licor 7000 non-dispersive infrared gas analyser used to measure the CO2 mole fraction (XCO2) of the dried air. The gas flow is stopped temporarily for the CO2 measurements, which are made at atmospheric pressure. A set of four CO2 standards that cover the range of CO2 values expected in the ocean are analysed about every four hours to calibrate the gas analyser. The standard gas concentrations are on the WMO-X2007 mole fraction scale for CO2-in-air. Atmospheric XCO2 (dry) is measured after the standards by pumping clean outside air from an intake on the forward mast of the ship. \n\nSeawater intake and ancillary data:\nThe seawater intake is located at about 5.5m depth in the bow of the ship. Sea surface salinity is measured using a thermosalinograph (Seabird Electronics SBE21) located next to the CO2 system. A remote temperature sensor (Seabird Electronics SBE 38) located at the intake is used to measure sea surface temperature (SST). The travel time between the intake and CO2 system is typically about 4 minutes with warming usually less than 0.6ºC. The thermosalinograph water is from the same intake, but the supply lines separate after the intake. A comparison of thermosalinograph and equilibrator temperature records shows the temperature difference in the two lines is generally less than 0.1ºC. The thermosalinograph water line travels outside the ship and is typically warmer than the equilibrator. The travel time in water line to the thermosalinograph is 2.5 minutes faster than to the equilibrator. \n\nMeteorological data, salinity, SST, and ships position and time are taken from the ships logging system. These parameters and the data quality are maintained by the Australian Marine National Facility.

本数据集由IMOS船舶走航CO2测量研究小组于2008年1月在“南方勘探者号”调查船（RV Southern Surveyor，IMOS平台代码：VLHJ）的SS012008航次中采集。

启航： 塔斯马尼亚州霍巴特，2008年1月11日
抵港： 塔斯马尼亚州霍巴特，2008年2月1日

CO2系统概述：
表层海水二氧化碳逸度（fCO2，fugacity of carbon dioxide）的测量采用通用海洋学公司（General Oceanics Inc.）的自动化系统（Model 8050；Pierrot等，2009）完成。将海水喷入平衡腔，顶空气体中的二氧化碳与海水达到气液平衡。顶空气体经泵输送依次通过热电冷凝器与纳菲昂干燥管，随后流经LI-COR 7000型非色散红外气体分析仪，以测量干燥空气的二氧化碳摩尔分数（XCO2）。测量二氧化碳时会暂时中断气流，所有测量均在大气压下进行。每隔约4小时便会分析一组覆盖海洋中预期二氧化碳浓度范围的4种二氧化碳标准气体，以对气体分析仪进行校准。该标准气体的浓度基于世界气象组织（WMO）-X2007空气中二氧化碳摩尔分数标度。标准气体测量完成后，通过抽取船舶前桅杆进气口处的清洁室外空气，对干燥大气中的XCO2进行测量。

海水采样口与辅助数据：
海水采样口位于船舶船首约5.5米水深处。表层海水盐度通过安装在CO2系统旁的温盐测量仪（Seabird Electronics SBE21）测量。安装在采样口处的远程温度传感器（Seabird Electronics SBE 38）用于测量表层海水温度（SST，sea surface temperature）。采样口与CO2系统之间的输水时长通常约为4分钟，输水过程中水温升高通常不超过0.6℃。温盐测量仪的取水点与CO2系统相同，但输水管道在采样口处分流。对温盐测量仪与平衡腔的温度记录进行对比后发现，两条输水管道的水温差通常不超过0.1℃。温盐测量仪的输水管道沿船舶外部铺设，因此水温通常高于平衡腔的输水管道。输水至温盐测量仪的时长比至平衡腔短2.5分钟。

气象数据、盐度、SST以及船舶位置与时间信息均取自船舶日志系统。上述参数及数据质量由澳大利亚海洋国家设施负责维护。