Waves, rain, and surface roughness at Ocean Station Papa

一项联合观测和预报模拟研究将讨论海洋表面波和雨之间的耦合。这些观测将扩展Papa海洋气象站（OWS-P）现有的时间序列，并利用漂流浮标进行更详细的测量。这些观测结果将用于改进谱风波模式的参数化，以及对有雨的地面湍流和海气通量相关变化的基本认识。这项研究的智力价值在于解决了雨对海洋表面波的抑制以及与之相关的表面粗糙度和表面湍流变化方面的知识空白。这项工作将通过在OWS-P进行长期实地观察，结合利用同一区域的机会部署进行短期进程研究，解决这一差距。这些结果将提高对耦合气候和预报模式的海气相互作用的理解。特别是，这项工作将使现有的频谱风浪预报模式（例如WAVEWATCH III、SWAN等）能够考虑降雨对波浪产生和消散的影响。这项工作的更广泛的影响是在一个关键参考地点的表面波时间序列的延续，以及对波浪预报和海气相互作用的总体公式的改进。其他影响包括本科教育，通过每年夏天的带薪实习（由项目直接资助）和参与NSF本科生研究经验项目（单独资助）。推广将通过更新的网站和为现有的应用物理实验室YouTube频道制作的短视频，以及在发现日（超过10,000人参加）等公共活动的摊位进行。该项目将测试以下假设：1。雨水抑制了海洋表面的波浪，尤其是频谱尾部的短波。这种抑制，加上对波浪的风输入的减少，导致波浪破碎的减少。波浪破碎的减少降低了表面粗糙度（影响阻力系数）和表面湍流（影响通量）。雨可以通过雨滴直接注入湍流来增加地面湍流，特别是在低到中等风的情况下，这与通过减少波浪破碎来减少地面湍流阻尼的间接作用相竞争。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

A combined observational and forecast modeling study will address the coupling between ocean surface waves and rain. The observations will extend an existing time series at Ocean Weather Station Papa (OWS-P) and complement those observations with more detailed measurements using drifting buoys. The observations will be used to improve parameterizations in spectral wind-wave models, as well as fundamental understanding of surface turbulence in the presence of rain and the related changes to air-sea fluxes. The intellectual merit of this research is addressing a knowledge gap in the suppression of ocean surface waves by rain and the associated changes in surface roughness and surface turbulence. The work will address this gap through long-term field observations at OWS-P, combined with a short-term process study using deployments of opportunity in the same region. The results will improve understanding of air-sea interactions for coupled climate and forecast models. In particular, this work will enable existing spectral wind-wave forecast models (e.g., WAVEWATCH III, SWAN, etc) to account for the effect of rain on wave generation and dissipation. The broader impacts of this work are in the continuation of a time series of surface waves at a key reference site, as well as improvements to wave forecasting and bulk formulae for air-sea interactions. Other impacts include undergraduate education, through paid internships each summer (funded directly by the project) and participation in the NSF Research Experiences for Undergraduate program (funded separately). Outreach will be conducted through an updated web site and short videos produced for an existing Applied Physics Lab YouTube channel, as well as booths at public events like Discovery Days (over 10,000 attendees).The project will test the following hypotheses:1. Rain suppresses ocean surface waves, especially the short waves in the `tail' of the spectrum.2. The suppression, together with a reduction in wind input to waves, leads to a reduction inwave breaking.3. The reduction in wave breaking reduces both the surface roughness (with implications fordrag coefficients) and the surface turbulence (with implications for fluxes).4. Rain may increase the surface turbulence through a direct injection of turbulence by raindrops,especially in low to moderate winds, competing with the indirect effect of the surfaceturbulence damping through a reduction in wave breaking.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.