Collaborative Research: Forcing, Energy Flow and Impacts of Oceanic Infragravity Waves

合作研究：海洋次重力波的强迫、能量流和影响

• 批准号: 1948020
• 负责人: Douglas Luther
• 金额: $ 27.89万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1948020&HistoricalAwards=false
• 关键词: Collaborative; Research; Forcing; Energy; Flow

This project will examine oceanic surface gravity waves with periods from 30 seconds to an hour, the ‘infragravity’ waveband. Existing observations of ocean bottom pressure, geomagnetic field, atmospheric pressure, and ocean gravity waves will be analyzed with spectral techniques to examine the mechanisms (sources) by which energy is used to generate infragravity waves (IGW). Sources include the interactions of tsunami and swell with coastlines, ocean surface tides, and energy from the solar normal modes that have previously been observed in solar wind, seismic, geomagnetic, barometric, and ionospheric data. IGWs can be important connectors between disparate phenomena, connecting source variability to the excitation of earth’s normal modes, flexing of ice shelves in Antarctica, contribution to mixing in the abyssal ocean, and adding ‘noise’ in altimeter data. If understood and modeled appropriately as IGW, such noise could be minimized, to improve such altimetry data. In addition, this project will contribute to the education of a graduate student in physical oceanography building the next generation of scientists capable of exploring our planet for a more environmentally secure future.As technology has expanded the availability of observations of terrestrial and extra-terrestrial variables, such as the solar wind and pressure at the bottom of the oceans, new information has yielded insight into how highly connected disparate phenomena can be. Of longstanding interest are so-called infragravity waves (IGWs; oceanic surface gravity waves at periods of 30 seconds to an hour) due to their excitation by tsunamis and swell (gravity wave periods less than 30 seconds) at the coasts. IGWs forced at the coasts are a factor that enhances flooding and erosion by tsunamis and swell. In the open ocean, IGWs are weaker, but have been found to be unexpected pathways for energy that engender remarkable phenomena, such as the continuous excitation of Earth's normal modes, signals that are now regularly used to explore the details of Earth's structure and composition. But understanding is limited regarding the various sources of energy for the IGWs, and the mechanisms this energy contributes to infragravity waves (i.e., the energy pathways). The principal investigators recently demonstrated the existence of two new energy sources: ocean surface tides and solar normal modes. This project will: (1) acquire more observational evidence of the tidal and solar energy pathways into the IGWs; and, (2) quantify the contributions of these two sources as a function of frequency, time period (e.g., season; 11-yr solar cycle) and location (e.g., geomagnetic latitude; marginal seas vs. open ocean). The relative contributions of these sources to IGWs, and especially their spatial distribution, are crucial characteristics for understanding the impacts of IGWs and their connections to the other phenomena noted above.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.

将使用光谱技术分析海洋底压，地磁场，大气压和海洋重力波的现有观察结果，以检查使用能量来产生非狂热波（IGW）的机制（来源）。来源包括海啸和膨胀与海岸线的相互作用，海面潮汐，以及来自太阳风，地震，地震，地震，气压和电离层数据的太阳能正常模式的能量。 IGW可以是不同现象之间的重要连接器，将源变异性与地球正常模式的兴奋联系在一起，弯曲南极洲的冰架，有助于在深渊海洋中混合的贡献以及在高度数据中添加“噪声”。如果将其理解为IGW并适当地建模，则可以将这种噪声最小化，以改善此类高度测定数据。此外，该项目将有助于对物理海洋学研究生的教育，以建立下一代的科学家，能够探索我们的星球，以实现更环保的未来。AS技术扩大了对陆地和地球外变量的观察的可用性，例如Solar Wind和Solar Wind and Pressive，例如在海洋的底部，新的信息可以使海洋的底部洞察到高度连接的差异。长期以来的感兴趣是所谓的内graveravity波（IGW；海洋表面重力波在30秒至一个小时时），由于海啸和膨胀（重力波（重力波周期少于30秒））以成本为代价，它们的兴奋是它们的兴奋。以成本为代价的IGW是一种因海啸和膨胀而增强洪水和侵蚀的因素。在开阔的海洋中，IGW较弱，但被发现是产生显着现象的能量的出乎意料的途径，例如地球正常模式的连续兴奋，这些信号现在被定期用于探索地球结构和组成的细节。但是，对IGW的各种能源来源的理解是有限的，并且该能量有助于内部的机制（即能量途径）。主要研究人员最近证明了两个新能源的存在：海面潮汐和太阳正常模式。该项目将：（1）将潮汐和太阳能途径的更多观察证据纳入IGW； （2）量化这两个源的贡献是频率，时间周期（例如季节； 11年太阳周期）和位置（例如，地磁纬度；边际海洋与开放海洋）的贡献。这些来源对IGW的相对贡献，尤其是它们的空间分布，是理解IGW的影响及其与上述其他现象的影响的关键特征。该奖项反映了NSF的法定任务，并通过使用该基金会的知识分子和更广泛的影响来评估Criteria诚实地认为，通过评估诚实地将其视为诚实的支持。