Collaborative Research: Physical processes in formation and breakdown of hypoxia in a tropical bay

本项目将结合持续监测数据、新观测数据和数值模型，研究巴拿马（巴伊亚德尔阿米兰特）热带海湾的缺氧情况。该项目将侧重于热带系统特有的物理过程。缺氧使海水的氧含量严重减少，是对河口和沿海水域的一种广泛有害的人为影响，并且在全球沿海地区正在增加。尽管热带海洋缺氧对维持重要渔业栖息地和沿海生物多样性的热带生态系统具有重要影响，但人们对热带海洋系统的缺氧了解甚少，研究不足。该项目将包括实地考察海湾的物理和化学参数，以及模拟动态和生物地球化学反应和解释观测数据的建模组成部分。该项目有望为热带系统中引发和控制缺氧的动力学提供新的理解。该项目的成果将通过科学会议、大学研讨会、公开演讲、网站和同行评议的期刊文章等形式进行传播。向更广泛的科学界传播结果将包括将于赠款的第三年在巴拿马举行的关于“了解加勒比地区缺氧”的讲习班。该研讨会将汇集来自整个加勒比地区的研究人员，与巴拿马当地研究人员和其他利益攸关方一起研究各种缺氧系统。该项目包括观测活动和数值模拟，以解决热带浅层系统缺氧的动力学问题。物理和化学测量旨在确定海湾季节性缺氧事件演变过程中的重要物理过程。巴伊亚阿尔米兰特是巴拿马博卡斯德尔托罗地区的一个热带海湾，经历了反复的季节性缺氧，导致广泛的白化和珊瑚和其他无脊椎动物的死亡。一个完全耦合的物理生物地球化学模型将为海湾开发，以测试动力学的理解。该项目还将利用史密森尼热带研究所（STRI）自2010年以来每周观测（温度、盐度和氧气）的历史记录，为我们的观测提供历史背景，并为模拟提供验证。调节低温沿海低氧底水通风的物理过程包括淡水流入和大气通量，它们影响密度分层、平流以及风、波和潮汐驱动的湍流混合。更好地了解热带海湾氧气变化的物理机制和环境条件，将对底栖生物生态学、湍流混合、幼虫连通性、沿海缺氧、海洋酸化和跨大陆架营养物质交换、污染物、缺氧水域产生丰富的见解。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。

This project is to study hypoxia in a tropical embayment in Panama (Bahia del Amirante) using a combination of ongoing monitoring data, new observations, and a numerical model. The project will focus on physical processes unique to tropical systems. Hypoxia, whereby marine waters become severely depleted in oxygen content, is a widespread deleterious anthropogenic influence on estuarine and coastal waters and is increasing in coastal regions globally. Hypoxia in tropical marine systems is poorly understood and understudied, despite the important implications for tropical ecosystems which sustain important fisheries habitats and coastal biodiversity. The project will include a field campaign to observe the physical and chemical parameters of the Bay as well as a modeling component to simulate the dynamic and biogeochemical responses and interpret the observational data. The project is expected to provide new understanding of the dynamics that initiate and control hypoxia in tropical systems. The results of this project will be disseminated through presentations at scientific meetings, seminars at universities, public talks, websites, and peer-reviewed journal articles. Communication of results to the broader scientific community will include a workshop on "Understanding hypoxia in the Caribbean" to be held in Panama in the third year of the grant. This workshop will bring together researchers from throughout the Caribbean working on diverse hypoxic systems with local Panamanian researchers and other stakeholders.This project includes an observational campaign and numerical simulations that will address the dynamics of hypoxia in shallow tropical systems. Physical and chemical measurements are designed to identify the important physical processes throughout the evolution of a seasonal hypoxic event in the Bay. Bahia Almirante is a tropical embayment in the Bocas del Toro region of Panama that has experienced repeated, seasonal hypoxia resulting in widespread bleaching and mortality of corals and other invertebrates. A fully-coupled physical biogeochemical model will be developed for the bay to test the dynamical understanding. The project will also leverage a historical record of weekly observations (temperature, salinity and oxygen) by the Smithsonian Tropical Research Institute (STRI) since 2010 to give historical context to our observations and to provide validation for the simulations. The physical processes regulating the ventilation of low-oxygen bottom waters in temperature coastal regions include inflow of fresh water and atmospheric fluxes, which affect density stratification, advection, and wind, wave, and tidal-driven turbulent mixing. A better understanding of the physical mechanisms and environmental conditions responsible for oxygen variability in tropical bays will yield rich insight into benthic ecology, turbulent mixing, larval connectivity, coastal hypoxia, ocean acidification and cross-shelf exchange of nutrients, pollutants, hypoxic waters.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.