CAREER: Marine Debris at Coastlines: predicting sources from drift, dispersion, and beaching via experiments and multiscale stochastic models

海洋和湖泊中漂浮的各种大小的海洋垃圾，从微塑料到更大的垃圾，是一个紧迫的全球问题，预计未来几年和几十年的投入将增加。通常，海洋垃圾污染的最严重影响是在海岸线，那里的经济和生态系统对污染更为敏感，垃圾可以积聚到高浓度。目前关于海岸线附近海洋垃圾运动的知识还不足以预测垃圾是如何漂移、分散和搁浅的。该项目旨在通过调查海岸线上海洋垃圾的命运和运输来填补这一知识空白。这项研究将产生新的和更精确的模型，用于研究不同大小和复杂形状的颗粒如何与海岸线上复杂的波浪和湍流相互作用并被输送。该项目还将包括重要的教育活动，包括与当地一所高中合作，利用各机构的专业知识来改善研究生培训，并增加来自不同背景的学生参与工程研究。这个项目的目标是建立一个海岸线海洋垃圾的多尺度随机模型，包括垃圾颗粒如何漂移、分散和搁浅。虽然海洋垃圾研究的大多数努力都集中在描述开阔水域和海滩沉积物的污染特征，但本项目将考虑碎片大小、形状和密度的复杂性如何与沿海环境中流动条件的复杂性相结合，以确定海洋垃圾的命运和运输。在多个尺度上的实验和理论方法将产生填充整个模型所需的参数。在实验方面，这将包括先进的流动和颗粒跟踪方法在不同的水波水槽和盆地。在理论方面，这将包括通过数学建模和实验数据分析发现适当的比例关系和碎片漂移、分散和搁浅的无量纲描述。总的来说，研究结果有望为海岸保护提供解决方案，防止碎片污染。该项目由NSF ENG/CBET流体动力学和环境工程项目共同资助。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。

Floating marine debris in oceans and lakes across a range of sizes from microplastics to larger debris is a pressing global issue with inputs projected to increase in the coming years and decades. Often, the worst impacts of marine debris pollution are at coastlines, where economies and ecosystems are much more sensitive to pollution and where debris can accumulate to high concentrations. Current knowledge of marine debris motion near coastlines is insufficient to predict how debris drift, disperse, and become beached. This project seeks to fill this knowledge gap by investigating the fate and transport of marine debris at coastlines. This research will produce new and more accurate models for how particles of different sizes and complex shapes interact with and are transported by complex wavy and turbulent flows at coastlines. The project will also include significant educational activities, including an initiative to leverage expertise across institutions to improve graduate student training and increase participation of students from diverse backgrounds in engineering research in partnership with a local high school.The goal of this project is to construct a multiscale stochastic model of marine debris at coastlines that includes how debris particles drift, disperse, and become beached. While most efforts in marine debris research have concentrated on characterizing pollution in open waters and in beach sediment, this project will consider how the complexities of debris size, shape, and density combine with the complexity of flow conditions in the coastal environment to determine marine debris fate and transport. Experimental and theoretical approaches at multiple scales will produce the parameters required to populate the overall model. On the experimental side, this will include advanced flow and particle tracking methods in different water wave flumes and basins. On the theoretical side, this will include discovering appropriate scaling relationships and dimensionless descriptions of debris drift, dispersion, and beaching through mathematical modelling and experimental data analysis. Overall, the results are expected to inform solutions for coastal protection against debris pollution. The project is co-funded by the NSF ENG/CBET Fluid Dynamics and Environmental Engineering programs.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.