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，流入大海的淡水地下水与潮汐和波浪作用渗透的咸地下水混合在一起。该区域的生物地球化学反应极大地影响了海滩生态，并决定了营养物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。通常假设地下水的最大盐度等于海水的最大盐度。然而，已观察到其浓度是海水的 3-6 倍。由于盐浓度对流体密度的影响，蒸发与波浪的相互作用可能是改变盐度分布和地下水流径的重要机制。该研究将为两名来自不同背景的研究生和本科生提供密集的现场和实验室经验，他们将与教育机会计划合作招募，该计划为新泽西理工学院代表性不足的少数族裔学生提供服务。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认识。 (1) 模型开发和升级将建立在海滩含水层蒸发和波浪动力学建模的最新进展的基础上，通过结合这些过程来解释多孔介质中的水、蒸汽和热传输，以及包含波浪作用的地下流体动力学。 (2) 数据收集将包括在特拉华州三个现场进行的一系列海滩盐度和水动力的详细测量，以更好地了解实际系统中的这些耦合效应。 (3) 特定地点和敏感性分析将对蒸发引起的盐度动力学的主要控制及其对潮间带混合区流动物理的影响产生新的认识。通过对一系列气候、水文地质和海洋条件进行分析，结果将捕获影响范围和精确条件，在这些条件下考虑这些过程是最重要的。该奖项反映了 NSF 的法定使命，并被认为值得通过以下方式获得支持：使用基金会的智力价值和更广泛的影响审查标准进行评估。