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

这项奖励的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。这项提议将资助在伊明格海西部边界流的OSNAP系泊处回收部署的氧传感器，以及在回收时进行深度校准，以及随后对数据的处理和分析。其目的是测量氧气，氧气通过几条途径将较深的边界流通风，从暴露在大气中的近地表海洋通向较深的边界流，并调查相关过程。在这样做的过程中，该项目还将提供有关溶解大气产生的二氧化碳从近表面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显著缓解了全球变暖，但随着全球变暖的持续，通风可能会下降，潜在地削弱这个二氧化碳汇，并降低整个大西洋的氧气水平。由于缺乏对溶解气体的直接观测，限制了准确的预算编制，并阻碍了对控制气体向深海封存的过程的了解。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方面的更多进展。该项目将支持一名职业生涯早期的拉美裔/拉丁裔女科学家和一名研究生，以及几项外联活动，包括通过博客记录海上经验以及与URM学生群体的互动。亚极地北大西洋的二氧化碳吸收被认为显著缓解了全球变暖；此外，该地区的氧气吸收防止了整个北大西洋的大规模缺氧。随着全球变暖的继续，对流预计会减少，这可能会削弱二氧化碳汇，并降低整个大西洋的氧气水平。然而，缺乏对溶解气体的直接观测，特别是在冬季和边界洋流区域，限制了准确的预算编制，并阻碍了我们对控制气体向深海固存的过程的理解。计划对这些有价值的新O2观测数据进行仔细的校准和分析，以强调对边界流通风和内部边界流交换背后的动力学的理解。科学问题是：1)斜向对流如何有效地直接通风边界流？2)通过从内陆排出拉布拉多海水(LSW)到达伊明格海边界流的氧气有多少？3)拉布拉多海水夹带在多大程度上设定了丹麦海峡溢流水(DSOW)的高氧气水平？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。这一裁决反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

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.