The Influence of Coastal-Trapped Waves on the Inner Continental Shelf: Temperature and Circulation Patterns

沿海陷波对内大陆架的影响：温度和环流模式

• 批准号: 0957948
• 负责人: Melanie Fewings
• 金额: $ 37.69万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-15 至 2013-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0957948&HistoricalAwards=false
• 关键词: Influence; Coastal; Trapped; Waves; Inner

Previous studies show that substantial fluctuations in sea level, along-shelf velocity, and water temperature along the West Coast of North America are due to coastal-trapped waves. These waves propagate poleward, have periods of days to weeks, are mainly driven by wind fluctuations, and are a mechanism by which winds in one location influence the coastal ocean in other locations far away. Remote wind fluctuations in Baja California have been observed to cause transport of warm and cold water masses onshore in the Southern California Bight, with implications for nutrient supply to kelp forests, larval transport, strength of internal tidal temperature fluctuations, and trapping or flushing of coastal pollution and harmful algal blooms. Coastal-trapped waves are also suggested to affect the frequency and strength of internal tidal bores all along the West Coast.This study will test the hypothesis that in the Santa Barbara Channel and around the Northern Channel Islands, along-shelf pressure gradients arriving as coastal-trapped waves generated by wind fluctuations in Baja California are a dominant source of variability in circulation and temperature. It will answer the questions 1) What effect do wind fluctuations in Baja California have on coastal pressure, velocity, temperature, and stratification? 2) How does Point Conception affect the propagation of fluctuations in coastal pressure, velocity, and temperature? and 3) Are internal tides and bores affected by thermocline shoaling due to coastal-trapped waves? This process-oriented study will utilize existing observations from i) mooring deployments covering 18 years, and ii) satellite winds and coastal temperature and sea-level data extending from Baja California to San Francisco, California. It will include comparisons of observed sea-level gradients to remote winds in Baja California, and of observed velocity and temperature signals near the coast to proven dynamical models of flow driven by a pressure gradient. These will help determine whether regional fluctuations in thermocline depth due to the passage of coastal-trapped waves enhance or inhibit internal-tidal temperature fluctuations, and lead to a dynamical understanding of the effects of remote winds in Baja California on the coastal ocean.BROADER IMPACTSCoastal-trapped waves occur worldwide, but their effect on water temperature near the shore and cross-shelf and along-shelf circulation is not well-described. The Santa Barbara Channel and Northern Channel Islands support important fisheries and kelp forest ecosystems and contain several Marine Protected Areas under ecosystem-based management. The influence of winds in Baja California via the coastal-trapped wave mechanism is probably important for delivery of biogenic particles, nutrients, and larvae to productive kelp forest ecosystems in the region. Therefore this study will benefit management and planning of marine protected areas as well as other interdisciplinary research such as at the NSF-supported Santa Barbara Coastal Long-Term Ecological Research project. It will also help maintain diversity in the sciences by supporting a female PI who is a new investigator.

先前的研究表明，北美西海岸沿着海平面、沿大陆架流速和水温的大幅波动是由于海岸捕获波造成的。这些波浪向极地传播，周期为几天到几周，主要由风的波动驱动，是一个地方的风影响远处其他地方的沿海海洋的机制。在下加利福尼亚的远程风波动已被观察到，导致运输的温暖和冷水团在南加州湾岸上，与营养供应的海带森林，幼虫运输，强度的内部潮汐温度波动，捕获或冲洗沿海污染和有害藻华的影响。还建议将影响所有沿着西Coast.This研究的频率和强度的内部涌潮，将测试假设，即在圣巴巴拉通道和周围的北方海峡群岛，沿大陆架的压力梯度到达海岸捕获波产生的风波动在下加利福尼亚是一个主要来源的环流和温度的变化。它将回答以下问题：1）下加利福尼亚的风波动对海岸压力、速度、温度和分层有什么影响？2)点概念如何影响海岸压力、速度和温度波动的传播？以及3）内潮和内孔是否受到海岸捕获波引起的温跃层变浅的影响？这项面向过程的研究将利用i）18年来的系泊部署和ii）从下加利福尼亚到加州弗朗西斯科的卫星风和沿海温度及海平面数据的现有观测结果。它将包括将观测到的海平面梯度与下加利福尼亚遥远的风进行比较，并将观测到的海岸附近的速度和温度信号与经证实的由压力梯度驱动的流动动力学模型进行比较。 这将有助于确定是否区域的温跃层深度波动，由于沿海捕获波的通道增强或抑制内部潮汐温度波动，并导致远程风在下加利福尼亚对沿海ocean.BroADER IMPACTS沿海捕获波的影响的动态理解发生在世界各地，但其对水温的影响附近的海岸和跨货架和沿货架流通没有得到很好的描述。圣巴巴拉海峡和北方海峡群岛支持重要的渔业和海带森林生态系统，并包含几个基于生态系统管理的海洋保护区。在下加利福尼亚的风的影响，通过海岸捕获波机制可能是重要的生物源颗粒，营养物质，和幼虫生产海带森林生态系统在该地区。因此，这项研究将有利于海洋保护区的管理和规划，以及其他跨学科的研究，如在国家科学基金会支持的圣巴巴拉沿海长期生态研究项目。它还将通过支持一名新的女性研究者来帮助保持科学的多样性。