Development of a Remote Analyzer of the CO2 System in Seawater Based on In Situ Measurement for pH and TCO2

伍兹霍尔海洋研究所将承担一个海洋科学仪器开发项目，以开发、建造和测试一种仪器，以便在较长一段时间内从海洋系泊和远程平台上自主地原位测量pH值和总二氧化碳(TCO2)。该仪器将被设计为在低于(2/小时)的频率下进行测量。据估计，无人看管的耐力约为6个月。这两个部分都是基于现有的实验室方法。PH测量使用成熟的分光光度实验室方法，而TCO2成分利用二氧化碳在半透膜上的交换，并在稀碱中检测由此产生的电导率变化。目标是达到(.002 pH单位和(5(摩尔/公斤))的精度。为了评估仪器性能，测试包括在深海中短期布线，在深海底栖着陆器上布设3或4个月，以及在近水面布设约3个月。

The Woods Hole Oceanographic Institution will undertake an ocean sciences instrumentation development project to develop, build and test an instrument to make autonomous in situ measurements of pH and Total carbon dioxide (TCO2)for extended periods from oceanographic moorings and remote platforms. The instrument will be designed to make measurements at frequencies less than (2/hr. Estimated unattended endurance will be about six months. Both components are based on existing laboratory methods. The pH measurements use well-developed spectrophotometric laboratory methods, while the TCO2 component utilizes exchange of CO2 across a semi-permeable membrane and detection of resulting conductivity changes in a dilute base. The objective is to achieve precision of ( (.002 pH units and (5 (mol/kg. To evaluate instrument performance, tests include short term wire deployments in the deep ocean, deployment on a benthic lander in the deep sea for 3 or 4 months, and near- surface deployment for approximately three months.