Collaborative Research: Impact of evaporation and waves on groundwater dynamics in tidally influenced beaches

合作研究：蒸发和波浪对受潮汐影响的海滩地下水动态的影响

• 批准号: 2130602
• 负责人: Holly Michael
• 金额: $ 17.68万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-15 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2130602&HistoricalAwards=false
• 关键词: Collaborative; Research; Impact; evaporation; waves

Beaches are an important part of the coastal zone where fresh groundwater flowing to the sea mixes with salty groundwater that infiltrates from tide and wave action. The biogeochemical reactions in this zone greatly impact beach ecology and determine the contribution of nutrients and contaminants to the coastal ocean. Salinity of the water is an important factor in these reactions, so understanding the distribution of salt is critical. It is typically assumed that the maximum salinity in the groundwater is equal to that of seawater. However, concentrations 3-6 times that of seawater have been observed. Evaporation interacting with waves may be an important mechanism that could change both salinity distributions and groundwater flowpaths, due to the influence of salt concentration on fluid density. The research will provide an intensive field and laboratory experience for two graduate students and undergraduates from diverse backgrounds who will be recruited in collaboration with the Educational Opportunity Program that serves under-represented minority students at New Jersey Institute of Technology. The project will provide a unique learning experience for students. This research will generate new understanding in three primary areas. (1) Model development and upscaling will build on recent advances in modeling evaporation and wave dynamics in beach aquifers by combining these processes to account for water, vapor, and heat transport in the porous medium coupled to subsurface hydrodynamics that incorporate wave action. (2) Data collection will include a set of detailed measurements of beach salinity and hydrodynamics at three field sites in Delaware to better understand these coupled effects in real systems. (3) Site-specific and sensitivity analyses will generate new understanding of the primary controls on evaporation-induced salinity dynamics and the resulting effects on flow physics in intertidal mixing zones. By extending analysis over a range of climatic, hydrogeological, and oceanic conditions, results will capture the range of effects and pinpoint conditions under which it is most important to consider these processes.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.

海滩是沿海地区的重要组成部分，新鲜的地下水流向海洋，将其与咸味的地下水混合在一起，从潮汐和波浪行动中渗透。该区域的生物地球化学反应极大地影响了海滩的生态，并确定了养分和污染物对沿海海洋的贡献。水的盐度是这些反应的重要因素，因此了解盐的分布至关重要。通常假定地下水中的最大盐度等于海水。但是，已经观察到了海水的浓度3-6倍。由于盐浓度对流体密度的影响，蒸发与波相互作用可能是一种重要的机制，可以改变盐度分布和地下水流道。这项研究将为来自不同背景的两名研究生和本科生提供密集的领域和实验室经验，这些研究生将与教育机会计划合作招募，该计划为新泽西技术学院的代表性不足的少数群体学生提供服务。该项目将为学生提供独特的学习体验。 这项研究将在三个主要领域产生新的理解。 （1）模型的开发和放大将基于在海滩含水层建模的最新进展，通过结合这些过程以说明水，蒸气和热传输的多孔培养基与地下流体动力学，以结合波动作用的多孔培养基。 （2）数据收集将包括一组在特拉华州的三个野外地点的海滩盐度和流体动力学的详细测量，以更好地了解实际系统中的这些耦合效果。 （3）特异性和灵敏度分析将对蒸发引起的盐度动力学的主要控制以及潮间混合区中流动物理的影响产生新的理解。通过扩展在气候，水文地质和海洋状况的一系列分析中，结果将捕获效果范围和确定条件的范围，最重要的是考虑这些过程。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来获得支持的。