Collaborative Research: Wind, Waves, Rain and their Effects on Air-Water Gas and Momentum Exchanges

合作研究：风、波浪、雨及其对空气-水气和动量交换的影响

• 批准号: 0930057
• 负责人: David Ho
• 金额: $ 27.98万
• 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: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0930057&HistoricalAwards=false
• 关键词: Collaborative; Research; Wind; Waves; Rain

OCE-0648275Small-scale ocean surface dynamics, including waves and turbulence, affect global climate through their impact on ocean-atmosphere exchange. However, the role of rainfall on surface fluxes, the dynamics of surface waves, the surface ocean , and the marine atmosphere boundary layer have not been studied in detail. A significant percentage of the shear stress at the ocean surface may be provided, at low wind speed, by rainfall. In addition, moderate rains will produce a dissipation of kinetic energy that is similar in magnitude to dissipations that are measuring in the surface-wave zone under breaking wave conditions. Higher rain rates cause much higher amounts of dissipation and thus significant amounts of mixing of the ocean surface can occur. This has important implications for gas, momentum and heat transfer between the atmosphere and the ocean. Rainfall also impacts the interpretation of surface-ocean remote sensing. There has been little work to date on the assessing the impact of rain. In this project, scientists from the University of Delaware and Columbia University, will conduct laboratory experiments to determine the amount of turbulent mixing and momentum transfer that occurs from the rain, investigate the dynamic effect of rain-induced stress on surface waves and examine the impact of rainfall on air-water gas transfer rates. Parameters such as rain rate, droplet size, wind speed, shear and turbulence will be measured to determine the mechanisms which cause significant mixing and also to explore the coupling between surface fluxes that are induced by rain and those that are induced by wind. In addition, the dynamic effects of rain-induced stresses on the surface waves will be investigated. The study has several important broader impacts. An improved understanding of how rain influences air-sea interactions will facilitate the improvement of parameterizations of these processes in models of the weather and climate. Students will be involved in the laboratory work and the results will be discussed through public outreach efforts.

小尺度海洋表面动力学，包括波浪和湍流，通过影响海-气交换来影响全球气候。然而，降雨对地表通量、表面波动力学、表面海洋和海洋大气边界层的作用还没有详细的研究。在低风速的情况下，海洋表面的剪切力有很大一部分可能是由降雨提供的。此外，中雨将产生动能的耗散，其强度与破碎波条件下在表面波区测得的动能耗散的量值相似。更高的降雨率会导致更大的耗散量，因此可能会发生大量的海洋表面混合。这对大气和海洋之间的气体、动量和热量传输有着重要的影响。降雨也对地表-海洋遥感的解释产生影响。到目前为止，关于评估降雨影响的工作还很少。在这个项目中，来自特拉华大学和哥伦比亚大学的科学家将进行实验室实验，以确定降雨产生的湍流混合和动量转移的量，调查降雨诱导应力对面波的动力学效应，并研究降雨对空气-水气体转移速率的影响。将测量雨率、水滴大小、风速、切变和湍流等参数，以确定造成显著混合的机制，并探索由降雨引起的地表通量与由风引起的地表通量之间的耦合。此外，还将研究雨致应力对表面波的动态影响。这项研究有几个重要的更广泛的影响。更好地理解降雨如何影响海-气相互作用，将有助于改进天气和气候模式中这些过程的参数。学生将参与实验室工作，并将通过公众宣传活动讨论结果。