The Role of Topography in Cross-Shelf-Break Tracer Exchange

地形在跨货架断裂示踪剂交换中的作用

• 批准号: RGPIN-2016-03865
• 负责人: Allen, Susan
• 金额: $ 2.91万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=708601
• 关键词: Role; Topography; Cross; Shelf; Break

The rotation of the Earth and its Coriolis force limit the exchange of water between the coastal ocean and the deep ocean. This limited exchange is often illustrated by significant changes in water properties, such as colour, near the location of the shelf-break. Various processes can break these dynamical constraints and allow exchange flow. One of these is caused by small scale topography such as underwater canyons. We propose to quantify the amount of specific, environmentally important tracers that are transported through submarine canyons. These tracers include nitrate (a limiting nutrient for plankton growth), dissolved inorganic carbon (which can be upwelled and increase the flux of CO2 to the atmosphere), and water containing low oxygen (which can cause anoxia on the shelf). We will include the impact of the enhanced mixing that occurs in canyons and the impact of flow interactions among multiple canyons or between canyons and headlands. Our goal is to determine the net impact of multiple canyons on tracer flux in a shelf region over seasonal cycles.

地球的自转及其科里奥利力限制了沿海海洋和深海之间的水交换。这种有限的交换通常表现为在货架断裂位置附近水的性质，如颜色的显著变化。 各种过程可以打破这些动态约束，并允许交换流。其中之一是由小尺度地形造成的，如水下峡谷。我们建议量化特定的，对环境有重要意义的示踪剂，通过海底峡谷运输。这些示踪剂包括硝酸盐（浮游生物生长的限制性营养物质），溶解的无机碳（可以上涌并增加CO2到大气中的通量）和含有低氧的水（可能导致大陆架缺氧）。 我们将包括在峡谷中发生的增强混合的影响和多个峡谷之间或峡谷和岬之间的流动相互作用的影响。 我们的目标是确定多个峡谷的示踪剂通量在货架区域的季节性周期的净影响。