Oxygen pathways into the deep ocean: investigating boundary current ventilation in the western Irminger Sea

该奖项全部或部分由2021年美国救援计划法案（公法117-2）资助。该提案将资助在Irminger海西部边界流的OSNAP系泊上部署的氧气传感器的恢复，沿着在恢复后进行深度校准，以及随后的数据处理和分析。其目的是测量O2，通风更深的边界电流通过几个途径导致从近地表海洋暴露于大气中，进入更深的边界电流，并调查负责的过程。在这样做的过程中，该项目还将提供有关溶解的大气中产生的二氧化碳从近表层海洋到深海的路径的信息。亚极地北大西洋的二氧化碳吸收被认为可以显着缓解全球变暖，但随着全球变暖的持续，通风可能会下降，可能会削弱这种二氧化碳汇，并降低整个大西洋的氧气水平。缺乏对溶解气体的直接观测限制了准确的预算编制，并妨碍了对将气体封存到深海的过程的理解。这些结果可能适用于其他海洋区域，并为海洋和气候模式中的溶解气体耦合提供信息。将促进这些数据的广泛使用，以推动这一关键区域的海洋化学、生态学和气候动力学的进一步发展。该项目将支持一名早期职业女性西班牙裔/拉丁裔科学家和一名研究生，沿着几项外展活动，包括通过博客记录海上经验和与URM学生团体的互动。北大西洋亚极地的二氧化碳吸收被认为可以显著缓解全球变暖;此外，该地区的氧气吸收可以防止整个北大西洋大规模缺氧。随着全球变暖的持续，对流预计将减少，可能会削弱这种二氧化碳汇，并降低整个大西洋的氧气水平。然而，由于缺乏对溶解气体的直接观测，特别是在冬季和边界流区域，限制了准确的预算编制，并阻碍了我们对将气体封存到深海的过程的理解。仔细校准和分析这些有价值的新的O2观测计划，强调了解的动态基础边界电流通风和走廊边界电流交换。提出的科学问题是：1）倾斜对流直接干扰边界流的有效性如何？2)有多少氧气通过拉布拉多海水（LSW）从内部排出到达伊明格海的边界流？3)LSW夹带在多大程度上设置了丹麦海峡溢流水（DSOW）中的高氧水平？这些结果可能适用于其他海洋区域，并为海洋和气候模型中的溶解气体耦合提供信息。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).This proposal would fund recovery of deployed oxygen sensors on the OSNAP moorings in the western boundary current of the Irminger Sea, along with deep calibration casts upon recovery, and subsequent processing and analysis of the data. The purpose is to measure O2 that ventilates the deeper boundary current through several pathways leading from the near surface ocean exposed to the atmosphere, into the deeper boundary current, and to investigate the processes responsible. In so doing, the project will also provide information about the pathways of dissolved atmosphere-derived CO2 from the near surface ocean to the deep. Carbon dioxide uptake in the subpolar North Atlantic is thought to significantly mitigate global warming, but as global warming continues, ventilation may decline, potentially weakening this CO2 sink and also reducing oxygen levels throughout the Atlantic. A lack of direct observations of dissolved gases has limited accurate budgeting and hindered understanding of the processes which govern the sequestration of gases into the deep ocean. These results may apply to other ocean regions and inform dissolved gas coupling in ocean and climate models. Broad use of these data will be promoted, to fuel additional advances in the ocean chemistry, ecology, and climate dynamics of this critical region. The project will support an early career female Hispanic/Latina scientist and a graduate student, along with several outreach activities, including documentation of at-sea experience through a blog and interaction with URM student groups.Carbon dioxide uptake in the subpolar North Atlantic is thought to significantly mitigate global warming; moreover, oxygen uptake in this region prevents large scale hypoxia throughout the North Atlantic. As global warming continues, convection is expected to decline, potentially weakening this CO2 sink and reducing oxygen levels throughout the Atlantic. However, a lack of direct observations of dissolved gases, particularly in winter and in boundary current regions, has limited accurate budgeting and has hindered our understanding of the processes which govern the sequestration of gases into the deep ocean. Careful calibration and analysis of these valuable new O2 observations is planned, to emphasize an understanding of the dynamics underlying boundary current ventilation and interior-boundary current exchange. Science question addressed are: 1) How effectively does slantwise convection directly ventilate boundary currents? 2) How much oxygen reaches the Irminger Sea’s boundary current through the draining of Labrador Sea Water (LSW) from the interior? 3) To what extent does LSW entrainment set the high oxygen levels in Denmark Strait Overflow Water (DSOW)? These results may apply to other ocean regions and inform dissolved gas coupling in ocean and climate models.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.