Dynamics of and Transport by Buoyant Coastal Ocean Currents Driven by Spatially Distributed and Highly-Time Dependent Coastal Mountain Rivers

空间分布和高度时间依赖性的沿海山区河流驱动的浮力沿海洋流的动力学和输送

基本信息

批准号：
1260394
负责人：
James Lerczak
金额：
$ 44.81万
依托单位：
Oregon State University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2013
资助国家：
美国
起止时间：
2013-03-01 至 2018-02-28
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1260394&HistoricalAwards=false
关键词：
Dynamics Transport Buoyant Coastal Ocean

项目摘要

Small mountainous river (SMR) systems have been shown to contribute a significant fraction of the global sediment and particulate organic carbon fluxes to the ocean. They are also important intermittent sources of nutrients and trace metals to the coastal ocean. Large-scale storm events are the dominant source of freshwater for these systems. Subsequent discharge to the coastal ocean occurs coherently across the river system as a large episodic pulse during which winds and waves are typically strong over the ocean. The dynamics of river plumes and buoyant coastal flows from these intermittent, but large pulses of discharge have received little scientific attention. This numerical modeling study will quantify the dynamics of the combined buoyancy and wind driven flows of an SMR system. Models of an idealized SMR system and the SMR system of the Oregon coastal range will be used to characterize the transport pathways of freshwater and river derived materials under different discharge and wind regimes. Intellectual Merit: The dynamics of buoyant coastal flows from the coherent but highly intermittent discharge of rivers of an SMR system, such as that of Oregon coastal range, have received very little scientific study. Yet the instantaneous combined discharge from these rivers can be greater than 20,000 m3/s during the winter, exceeding the discharge of the larger Columbia River to the north. Buoyancy forcing on the inner shelf must be important during these periods. This study will quantify the significance of SMR buoyancy forcing, characterize the interactions between the buoyancy driven and wind driven circulation of the Oregon inner shelf and quantify the fate of materials derived from SMR estuaries and the connectivity between SMR estuaries along the Oregon coast. Broader Impact: The principal investigator will collaborate with Lincoln County School District teachers to develop high school curriculum material focused on watershed transport processes, the impact of rivers on the coastal ocean, and scientific methods used to study river, estuary, and coastal flow including modeling and measurement methods. The curriculum will be shared broadly through online dissemination. In addition, model predictions of current variability and a description of the dominant forcing regimes of the Oregon inner shelf will be provided to the Northwest National Marine Renewable Energy Center in order to facilitate their wave energy research, development, device testing and impact studies off the Oregon coast. A PhD graduate student will be trained under this grant. The focus of her/his research will be on understanding the role of SMR systems on buoyant coastal circulation off of Oregon.

研究表明，小型山区河流（SMR）系统向海洋贡献了全球沉积物和颗粒有机碳通量的很大一部分。它们也是沿海海洋营养物和微量金属的重要间歇来源。大规模风暴事件是这些系统的主要淡水来源。随后向沿海海洋的排放在整个河流系统中连续发生，作为一个大的间歇性脉冲，在此期间海洋上风和波浪通常很强。这些间歇性但大的排放脉冲所产生的河流羽流和漂浮的沿海水流的动态很少受到科学关注。这项数值模型研究将量化 SMR 系统的浮力和风力驱动流组合的动力学。理想化的 SMR 系统和俄勒冈州沿海范围的 SMR 系统模型将用于描述不同流量和风况下淡水和河流衍生物质的传输路径。智力价值：SMR系统（例如俄勒冈州沿海地区）的河流连贯但高度间歇性排放产生的浮力沿海流的动力学，受到的科学研究很少。然而，这些河流在冬季的瞬时总流量可能超过 20,000 立方米/秒，超过了北部较大的哥伦比亚河的流量。在这些时期内架上的浮力一定很重要。这项研究将量化SMR浮力强迫的重要性，表征俄勒冈内陆架浮力驱动和风驱动环流之间的相互作用，并量化来自SMR河口的物质的命运以及沿俄勒冈海岸SMR河口之间的连通性。更广泛的影响：首席研究员将与林肯县学区教师合作开发高中课程材料，重点关注流域运输过程、河流对沿海海洋的影响，以及用于研究河流、河口和沿海流动的科学方法，包括建模和测量方法。课程将通过在线传播广泛共享。此外，将向西北国家海洋可再生能源中心提供当前变化的模型预测和俄勒冈内陆架主要强迫机制的描述，以促进其波浪能研究、开发、设备测试和影响研究。俄勒冈海岸。一名博士研究生将在这笔资助下接受培训。她/他的研究重点是了解 SMR 系统对俄勒冈州沿海活跃环流的作用。