Icelandic Coastal Current interactions with peninsulas, bays, winds, and ocean currents controlling freshwater export and retention

冰岛沿岸流与半岛、海湾、风和洋流的相互作用控制着淡水的输出和保留

• 批准号: 2242070
• 负责人: Michael Whitney
• 金额: $ 67.16万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2242070&HistoricalAwards=false
• 关键词: Icelandic; Coastal; Current; interactions; peninsulas

The Icelandic Coastal Current is a buoyant (brackish) current that moves past coastal headlands and bays. This project will use the Icelandic Coastal Current as a case study to advance understanding of and quantify transport of water across the continental shelf caused by coastal land-forms, bottom variations, winds, and offshore flows. The project will draw information from drifting floats and computer simulations to track waters from the Icelandic Coastal Current. Computer simulations will also analyze the sensitivity of buoyant transport to shifts in river discharge variations associated with 21st and 22nd century warming. Simulations will track buoyant waters with artificial tracers that will provide information on the time it takes for these waters to flush out of the region. Simulations will leverage hydrographic observations by Iceland’s Marine & Freshwater Research Institute, and satellite measurements that distinguish the edge of the buoyant current. As broader impacts, the project will support one postdoctoral researcher and one graduate student. It will also incorporate findings into undergraduate and graduate classes, and post YouTube videos on river influences in the marine environment. The PI will participate in educational events at a public school system with a diverse student population.This study will examine freshwater export from Icelandic rivers to the North Atlantic Ocean. Iceland is the study region as it has an assortment of shelf conditions (e.g., wide and narrow shelf widths, high and low river input regions, extensive canyons and no canyons, headlands of different radii of curvature, upwelling and downwelling conditions) that allow exploration of a wide range of shelf-ocean interactions. In addition, the system is a gateway to the Arctic with a complex hydrological cycle (having river systems fed by glacial melt and precipitation) that are being impacted by climate change. Several specific objectives pertain to the offshore transport of coastal buoyant water in the presence of complex coastal topography, wind, and open ocean forcing. The research will address these objectives with doubly-nested realistic ROMS simulations with an outer resolution of 4km and an inner resolution of 0.5 km, and with drifter releases in the context of the buoyancy-driven Icelandic Coastal Current. Numerical simulations will be validated with data from Iceland’s Marine & Freshwater Research Institute and the drifter releases. Simulations will investigate different climate change scenarios focused on predicted changes in the hydrological cycle. Analyses will quantify shelf-ocean exchanges including tracer fluxes across the shelf break, calculations of Eddy Kinetic Energy fields, and residence times.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.

冰岛海岸流是一种漂浮的(微咸水)流，流经沿海的海角和海湾。该项目将使用冰岛沿岸流作为案例研究，以促进对沿海地貌、海底变化、风和离岸水流造成的跨大陆架的水运输的了解和量化。该项目将从漂浮的浮标和计算机模拟中提取信息，以跟踪冰岛海岸洋流中的水域。计算机模拟还将分析浮力输送对与21世纪和22世纪变暖有关的河流流量变化变化的敏感性。模拟将使用人造示踪剂跟踪浮力水域，这些示踪剂将提供这些水域冲出该地区所需时间的信息。模拟将利用冰岛海洋与淡水研究所的水文观测，以及区分浮流边缘的卫星测量。作为更广泛的影响，该项目将支持一名博士后研究员和一名研究生。它还将把研究结果纳入本科生和研究生的课堂，并发布关于河流对海洋环境影响的YouTube视频。这项研究将考察从冰岛河流到北大西洋的淡水出口。冰岛是研究区域，因为它有各种各样的陆架条件(例如，宽阔和狭窄的陆架宽度、高和低的河流输入区域、广袤的峡谷和没有峡谷的峡谷、不同曲率半径的海角、上升流和下升流条件)，可以探索广泛的陆架-海洋相互作用。此外，该系统是通往北极的门户，具有复杂的水文循环(河流系统以冰川融化和降水为水源)，正受到气候变化的影响。有几个具体目标涉及在复杂的沿海地形、风和公海强迫存在的情况下沿海浮水的近海运输。这项研究将通过外部分辨率为4公里、内部分辨率为0.5公里的双重嵌套现实ROMS模拟以及浮力驱动的冰岛海岸流背景下的漂流释放来解决这些目标。数值模拟将使用冰岛海洋与淡水研究所和漂流者释放的数据进行验证。模拟将调查不同的气候变化情景，重点是预测的水文循环变化。分析将量化陆架-海洋交换，包括跨陆架断裂的示踪剂通量、涡动能场的计算和停留时间。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。

项目成果

Mixing of the Connecticut River Plume During Ambient Flood Tides: Spatial Heterogeneity and Contributions of Bottom‐Generated and Interfacial Mixing

• DOI: 10.1029/2023jc020423
• 发表时间: 2024-03
• 期刊: Journal of Geophysical Research: Oceans
• 作者: M. Whitney;P. Spicer;D. MacDonald;Kimberly D. Huguenard;K. Cole;Yan Jia;Nikiforos Delatolas