A new tool for ocean carbon cycle and ocean acidification studies

海洋无机碳系统对海洋科学家乃至所有人都非常感兴趣，因为它包含了关于海洋生产力、人为二氧化碳的来源和汇以及海洋酸化的重要信息。总碱度是重要的无机碳参数之一，已通过船舶和实验室方法广泛测量。目前，还没有商业上可用的现场总碱度传感器。在这个项目中，蒙大拿大学的研究人员将进一步开发和测试一种新的自主系统，称为SAMI-ALK，用于测量总碱度。这一新系统将通过在船舶不常出没的地点进行近乎连续的测量，扩大对总碱度和无机碳循环的理解。这一仪器的开发将为海洋研究提供一种新的仪器，从而对海洋学界和海洋酸化研究产生更广泛的重要影响。该项目还将为研究生和本科生提供培训机会，并将继续通过一个大学附属博物馆支持关于海洋酸化的公共宣传。虽然pH是海洋酸化的“确凿证据”，二氧化碳分压对气体交换计算至关重要，但对于大多数无机碳研究，必须对整个无机碳系统进行量化。使用自主传感器准确和精确地量化所有无机碳物种一直是海洋生物地球化学家的长期目标，但直到最近，对无机碳系统的全面表征还仅限于基于船舶和实验室的测量。总碱度就是这样一个参数，因为由于缺乏能够进行现场测量的仪器，对其研究一直受到限制。这项研究将解决这一问题，并通过进一步开发一种自主的、就地测量海水总碱度的系统，即潜水式自主系泊总碱度仪器(SAMI-ALK)，推动无机碳研究。该仪器的初步测试显示出了巨大的前景，通过这个项目，研究人员将进行实验室实验，以提高其性能。两个新的原型仪器将在实验室和现场评估中进行测试。

The ocean inorganic carbon system is of great interest to marine scientists, and indeed all people, because it contains important information about ocean productivity, the sources and sinks of anthropogenic carbon dioxide, and ocean acidification. Total alkalinity is one of the critical inorganic carbon parameters and has been widely measured through ship and laboratory-based methodologies. At this time, there are no commercially-available in situ sensors for total alkalinity. In this project, researchers at the University of Montana will further develop and test a new autonomous system, known as the SAMI-alk, for measuring total alkalinity. This new system will expand understanding of total alkalinity and the inorganic carbon cycle by making near continuous measurements in locations not frequented by ships. The development of this instrument will have important broader implications for the oceanographic community and ocean acidification research by providing a novel instrument for ocean research. This project will also provide training opportunities to graduate and undergraduate students, and will continue to support public outreach on ocean acidification through a university-affiliated museum.Studies focused on the marine carbon cycle and ocean acidification pose a number of measurement challenges. While pH is the ocean acidification "smoking gun" and partial pressure of CO2 is critical for gas exchange calculations, the full inorganic carbon system must be quantified for most inorganic carbon studies. Using autonomous sensors to accurately and precisely quantify all of the inorganic carbon species has been a long-standing objective for marine biogeochemists, but full characterization of the inorganic carbon system has, until recently, been limited to ship and laboratory-based measurements. Total alkalinity is one such parameter as its research has been limited by the lack of instrument capable of making in situ measurements. This research will address this problem and advance inorganic carbon studies through the further development of an autonomous, in situ system to measure seawater total alkalinity, known as the submersible autonomous moored instrument for total alkalinity (SAMI-alk). Preliminary testing of the instrument showed great promise, and through this project, researchers will conduct lab experiments to improve its performance. Two new prototype instruments will be tested in laboratory and field evaluations.