Collaborative Research: Oceanic Response to Atmospheric Forcing in the Kuroshio Extension

合作研究：黑潮延伸区海洋对大气强迫的响应

• 批准号: 0827280
• 负责人: Jae Hun Park
• 金额: $ 20.26万
• 依托单位: University of Rhode Island
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0827280&HistoricalAwards=false
• 关键词: Collaborative; Research; Oceanic; Response; Atmospheric

It is important to understand the generation and propagation of near-inertial internal waves, which are thought to contribute to deep-ocean mixing and maintenance of the abyssal stratification. Mesoscale eddies and currents affect the subsurface pathways of near-inertial waves from the mixed layer to the sea floor, and may deflect, trap, and focus them. Recent numerical models support these predictions, but much work remains to understand and verify how near inertial waves propagate to redistribute their energy in and under strong current systems. Due to the intense air-sea interactions in the Kuroshio Extension, ocean variability can potentially affect the winds and climate in remote regions. In particular, the subtropical mode water (STMW) has been considered as a large upper-ocean heat reservoir closely linked to the climate system. The non-uniform cooling and deepening of the surface mixed layer forms the STMW during winter with high variability in space and time. This project will investigate the upper and deep ocean response to atmospheric forcing in the Kuroshio region using oceanic and atmospheric observations collected as part of the Kuroshio Extension System Study (KESS) and the Kuroshio Extension Observatory (KEO) programs. The project will focus on the generation of near-inertial motions from the wind, how and where they propagate and dissipate, and how they directly affect the mass and heat budget of the mixed layer and STMW. The KESS array, deployed during May 2004?June 2006, comprised subsurface moorings with moored profilers and current meters, and inverted echo sounders equipped with near-bottom pressure and current sensors. KEO, a moored surface buoy, was first deployed in 2004 as part of KESS and is now part of the sustained ocean climate observing system. The KESS array is uniquely suited to conduct these studies due to its combination of vertical, horizontal, and temporal resolution and extent of spatial coverage. Understanding gained from this project has broad applicability in testing parameterizations of mixing in climate models and theoretical concepts of how near-inertial waves can be carried, trapped, and concentrated by strong current systems. The processes and feedbacks related to mode water formation by air-sea interaction are likely to be important in regions where strong winds blow over an ocean full of fronts and mesoscale eddies such as around the Southern Ocean. These processes are of great importance for climate variability, the focus of the Climate Variability and Prediction (CLIVAR) program. KESS has been included in CLIVAR from its planning phase and its findings complement other U.S. CLIVAR studies (e.g., CLIMODE, SAMFLOC, and DIMES). As global ocean models and wind fields achieve increasingly high resolution, allowing direct simulation of near-inertial waves, it will be important to have documented examples of the oceanic response in particular of the near-inertial waves in a strong mesoscale flow field to episodic atmospheric forcing.

必须了解近惯性内波的产生和传播，因为近惯性内波被认为有助于深海混合和维持深海分层。中尺度涡旋和海流影响近惯性波从混合层到海底的次表层路径，并可能使其偏转、捕获和聚焦。最近的数值模型支持这些预测，但还有很多工作要做，以了解和验证如何近惯性波传播，以重新分配其能量在强电流系统。由于黑潮延伸区强烈的海气相互作用，海洋变化可能会影响偏远地区的风和气候。特别是，亚热带模态水（STMW）已被认为是一个大型的上层海洋热库密切相关的气候系统。非均匀冷却和加深的地面混合层形成的STMW在冬季的空间和时间的变化很大。该项目将利用作为黑潮延伸系统研究（KESS）和黑潮延伸观测站（KEO）计划的一部分收集的海洋和大气观测数据，研究黑潮区域上层和深海对大气强迫的响应。该项目将侧重于从风中产生近惯性运动，它们如何以及在何处传播和消散，以及它们如何直接影响混合层和STMW的质量和热量预算。2004年5月部署的KESS阵列？2006年6月，包括带有系泊剖面仪和海流计的地下系泊装置，以及配备近底压力和海流传感器的倒置回声测深仪。KEO是一个系泊水面浮标，于2004年作为KESS的一部分首次部署，现在是持续海洋气候观测系统的一部分。KESS阵列是唯一适合进行这些研究，由于其组合的垂直，水平和时间分辨率和空间覆盖范围。从这个项目中获得的理解具有广泛的适用性，在测试参数化的混合在气候模式和理论概念的近惯性波可以携带，捕获，并通过强电流系统集中。与海气相互作用形成模式水有关的过程和反馈可能在强风吹过充满锋面和中尺度涡旋的海洋的区域（如南大洋周围）很重要。这些过程对气候变率非常重要，气候变率和预测（CLIVAR）计划的重点。KESS从规划阶段就被纳入CLIVAR，其研究结果补充了其他美国CLIVAR研究（例如，CLIMODE、SAMFLEND和DIMES）。随着全球海洋模式和风场的分辨率越来越高，可以直接模拟近惯性波，重要的是要有记录的例子，海洋的反应，特别是近惯性波在一个强大的中尺度流场中的情景大气强迫。