Collaborative Research: Estuarine Response to Climate Forcing

合作研究：河口对气候强迫的响应

• 批准号: 0961423
• 负责人: Raymond Najjar
• 金额: $ 32.27万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-15 至 2015-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0961423&HistoricalAwards=false
• 关键词: Collaborative; Research; Estuarine; Response; Climate

An investigation into the causes of interannual variability in estuarine salinity, stratification and circulation will be conducted using salinity observations, statistical methods, realistic 3-Dimensional hydrodynamic models, and simplified 2-Dimensional numerical models. The overall objective is to quantify interannual variability of estuarine circulation, stratification, and salinity, to explain the physical mechanisms responsible for such variability, and provide an assessment of the likely changes in these metrics in response to future climate change. Observational analysis and 3-Dimensional modeling will be focused on Chesapeake and Delaware Bays, for which (a) extensive salinity databases exist, and (b) a robust numerical model has been developed and validated. Process-oriented modeling studies will be conducted to examine how the estuaries respond to interannual variability in river runoff and shelf salinity, sea-level rise and potential changes in tidal and wind mixing. Multiple model hindcasts will be conducted in which the individual impacts of interannual variability in open-ocean sea level, river flow, shelf salinity, and meteorological forcing are assessed. Statistical models will be applied to the historical salinity data to investigate how salt intrusion length and estuarine stratification vary with river flow, shelf salinity and sea level rise. Projections of future climate impacts on these estuaries will be made by using the regional output of state-of-the art climate models that have been extensively evaluated for the Mid-Atlantic region. General insights into the sensitivity of estuarine physical processes to climate variability and change will be afforded by (1) the differing physics of Chesapeake Bay (partially mixed) and Delaware Bay (well mixed); (2) process oriented and realistic 3-Dimensional modeling studies; and (3) configuration of 2-Dimensional semi-analytical models over a large parameter space of river flow, tidal velocity amplitude, and estuarine geometry.Intellectual Merit. Much of current estuarine research focuses on relatively short time scales (tidal, weather-related, and seasonal). Little is known of interannual variability in estuarine salinity, stratification, and circulation. The inevitability of sea-level rise and climate change demands a rigorous, physically based approach for quantifying their impacts. This project addresses that need with a collaborative effort between two teams with complementary expertise in numerical modeling, estuarine dynamics, climate change impacts, and time-series analysis.Broader Impacts. This research project will impact the broader community of estuarine scientists and coastal managers as it will better quantify the potential impacts of climate change on estuarine salinity and stratification, factors that greatly influence water quality and the sustainability of living resources such as oysters and crabs. The long-term model simulations and analysis products will be made available to the Chesapeake and Delaware Bay management communities as they prepare for the impacts of climate change. Results will also be communicated to a broad range of stakeholders, including the general public, through several climate assessment activities underway in the Mid-Atlantic Region. Because the modeling and data analysis approaches developed here can be applied to any estuary, and because we will utilize simplified 2-Dimensional model to provide insights about the potential impacts of climate change on a broad class of estuaries, the impacts of the work extend beyond Chesapeake and Delaware Bays. Educational impacts of the proposal are through the support of graduate and post-doctoral research at the interface of the disciplines of estuarine dynamics and climate change.

利用盐度观测、统计方法、三维水动力模型和简化的二维数值模型，对河口盐度、分层和环流年际变化的原因进行了研究。总体目标是量化河口环流，分层和盐度的年际变化，以解释这种变化的物理机制，并提供这些指标的可能变化的评估，以应对未来的气候变化。观测分析和三维建模将侧重于切萨皮克和特拉华州海湾，（a）存在广泛的盐度数据库，（B）已开发并验证了稳健的数值模型。将进行面向过程的模拟研究，以研究河口如何对河流径流和陆架盐度、海平面上升以及潮汐和风混合的潜在变化的年际变化作出反应。将进行多模式后报，其中评估公海海平面、河流流量、大陆架盐度和气象强迫的年际变化的个别影响。统计模型将应用于历史盐度数据，以调查盐侵入长度和河口分层如何随河流流量、陆架盐度和海平面上升而变化。未来气候对这些河口的影响的预测将使用最先进的气候模型的区域输出，已广泛评估中大西洋地区。河口物理过程对气候变率和气候变化的敏感性的一般认识将由（1）切萨皮克湾不同的物理特性提供（部分混合）和特拉华州湾（2）面向过程和现实的三维建模研究;以及（3）在河流流量、潮汐速度幅值和河口的几何形状，智力上的优点目前的河口研究大多集中在相对较短的时间尺度（潮汐，天气相关的，和季节性）。人们对河口盐度、分层和环流的年际变化知之甚少。海平面上升和气候变化的不可避免性要求采取严格的、基于物理的方法来量化其影响。该项目通过两个团队之间的合作努力来满足这一需求，这两个团队在数值模拟、河口动力学、气候变化影响和时间序列分析方面具有互补的专业知识。该研究项目将影响更广泛的河口科学家和沿海管理人员，因为它将更好地量化气候变化对河口盐度和分层的潜在影响，这些因素极大地影响了水质和牡蛎和螃蟹等生物资源的可持续性。长期模型模拟和分析产品将提供给切萨皮克和特拉华州海湾管理社区，因为他们准备应对气候变化的影响。评估结果还将通过中大西洋区域正在开展的几项气候评估活动传达给广大利益攸关方，包括公众。由于这里开发的建模和数据分析方法可以应用于任何河口，因为我们将利用简化的二维模型提供有关气候变化对广泛的河口类的潜在影响的见解，工作的影响超出了切萨皮克和特拉华州海湾。该提案的教育影响是通过支持河口动力学和气候变化学科界面的研究生和博士后研究。