Collaborative Research: Autonomous alkalinity sensors: design improvements and in situ testing

PI要求提供资金，以进行设计改进并完成对测量海水总碱度的自主传感器（SAMI-alk）的评估。总碱度（AT）是四个可测量的溶解无机碳参数之一，因此在海洋碳循环研究中至关重要。AT通常作为船上水文测量和海洋时间序列的一部分进行测量，最近已成为海洋酸化研究的一个关键参数。自动AT传感器可与市售的其他CO2参数传感器（即pH和pCO 2）结合使用，以远程量化无机碳系统。例如，如果精确测量pH和AT，则可以计算总溶解无机碳（DIC）、碳酸盐和CaCO 3饱和状态。这些参数的长期系泊量化尚不可能。通过之前的NSF资助，我们证明了一种名为示踪剂滴定（TMT）的新型滴定方法可以通过消除传统AT滴定所需的体积或重量测量来简化AT分析。SAMI-alk在实验室和巡航期间都进行了测试。航行中的表现不如实验室测试的好。该提案要求提供资金，以完成SAMI-alk的开发和评估。 测量碱度的能力是酸化研究的关键需求。如果成功，这里提议的仪器开发将为了解海洋生态系统对酸化的脆弱性和反应提供一个重要工具。PI积极追求他过去开发的自主仪器的商业化。拟议的碱度传感器的商业化将大大扩大该技术的影响，使其广泛提供给海洋科学界。该项目包括对一名本科生的资助。

The PI request funding to undertake design improvements and complete the evaluation of an autonomous sensor for measurement of seawater total alkalinity (SAMI-alk). Total alkalinity (AT) is one of the four measureable dissolved inorganic carbon parameters and is therefore of paramount importance in the study of carbon cycling in the oceans. AT is commonly measured as part of shipboard hydrographic surveys and ocean time-series and has more recently become a critical parameter for ocean acidification studies. An autonomous AT sensor can be used in combination with other CO2 parameter sensors that are commercially available, i.e. pH and pCO2, to remotely quantify the inorganic carbon system. For example, if pH and AT are accurately measured, total dissolved inorganic carbon (DIC), carbonate, and CaCO3 saturation state can be calculated. Long-term mooring based quantification of these parameters is not yet possible. Through a previous NSF grant, we demonstrated that a novel titration methodology named Tracer Monitored Titration (TMT) could simplify AT analysis by eliminating the need for volumetric or gravimetric measurements required for conventional AT titrations. The SAMI-alk was tested both in the lab and during a cruise. The performance on the cruise was not as good as the laboratory tests. This proposal requests funds to complete the SAMI-alk development and evaluation.Broader Impacts: The ability to measure alkalinity is a key need for acidification research. If successful, the instrumentation development proposed here will provide an important tool for understanding the vulnerability and response of marine ecosystems to acidification. The PI has actively pursued commercialization of the autonomous instruments that he has developed in the past. Commercialization of the proposed alkalinity sensor through will greatly broaden the impacts of the technology, making it broadly available to the ocean sciences community. The project includes funding for on undergraduate student.