Collaborative Research: Snow Transport in Katabatic Winds and Implications for the Antarctic Surface Mass Balance: Observations, Theory, and Numerical Modeling

合作研究：下降风中的雪输送及其对南极表面质量平衡的影响：观测、理论和数值模拟

• 批准号: 2035078
• 负责人: Marco Giometto
• 金额: $ 62.88万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2035078&HistoricalAwards=false
• 关键词: Collaborative; Research; Snow; Transport; Katabatic

1. A non-technical explanation of the project's broader significance and importance, that serves as a public justification for NSF funding. This part should be understandable to an educated reader who is not a scientist or engineer.Katabatic or drainage winds, carry high-density air from a higher elevation down a slope under the force of gravity. Although katabatic flows are ubiquitous in alpine and polar regions, a surface-layer similarity theory is currently lacking for these flows, undermining the accuracy of numerical weather and climate prediction models. This project is interdisciplinary, and will give graduate and undergraduate students valuable experience interacting with researchers outside their core discipline. Furthermore, this project will broaden participating in science through recruitment of students from under-represented groups at OU and CU through established programs.The Antarctic Ice Sheet drives many processes in the Earth system through its modulation of regional and global atmospheric and oceanic circulations, storage of fresh water, and effects on global albedo and climate. An understanding of the surface mass balance of the ice sheets is critical for predicting future sea level rise and for interpreting ice core records. Yet, the evolution of the ice sheets through snow deposition, erosion, and transport in katabatic winds (which are persistent across much of the Antarctic) remains poorly understood due to the lack of an overarching theoretical framework, scarcity of in situ observational datasets, and a lack of accurate numerical modeling tools. Advances in the fundamental understanding and modeling capabilities of katabatic transport processes are urgently needed in view of the future climatic and snowfall changes that are projected to occur within the Antarctic continent. This project will leverage the expertise of a multidisciplinary team of investigators (with backgrounds spanning cryospheric science, environmental fluid mechanics, and atmospheric science) to address these knowledge gaps.2. A technical description of the project that states the problem to be studied, the goals and scope of the research, and the methods and approaches to be used. In many cases, the technical project description may be a modified version of the project summary submitted with the proposal. Using field observations and direct numerical simulations of katabatic flow, this project is expected--- for the first time---to lead to a surface-layer similarity theory for katabatic flows relating turbulent fluxes to mean vertical gradients. The similarity theory will be used to develop surface boundary conditions for large eddy simulations (LES), enabling the first accurate LES of katabatic flow.The numerical tools that the PIs will develop will allow them to investigate how the partitioning between snow redistribution, transport, and sublimation depends on the environmental parameters typically encountered in Antarctica (e.g. atmospheric stratification, surface sloping angles, and humidity profiles), and to develop simple models to infer snow transport based on satellite remote sensing and regional climate modelsThis 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.

1。对该项目更广泛的重要性和重要性的非技术解释，是NSF资金的公共理由。这部分对于不是科学家或工程师的受过教育的读者应该是可以理解的。卡塔比特或排水风，从更高的海拔高度下沿重力下的斜坡携带高密度的空气。 尽管katabatic流在高山和极地区域无处不在，但目前缺乏这些流的表面层相似性理论，破坏了数值天气和气候预测模型的准确性。该项目是跨学科的，将为毕业生和本科生提供宝贵的经验，与核心学科以外的研究人员互动。此外，该项目将通过既定的计划从OU和CU中代表性不足的群体招募学生来扩大参与科学的参与。南极冰盖通过调节区域和全球大气和海洋循环，存储淡水，以及对全球Artedo and Climate的影响，通过调节区域和全球大气和海洋循环，对地球系统中的许多过程进行了许多过程。了解冰盖的表面质量平衡对于预测未来的海平面上升和解释冰核记录至关重要。然而，由于缺乏总体的理论框架，现场观察数据集的稀缺以及缺乏准确的数值模型工具，因此通过雪沉积，侵蚀和运输的冰盖演变（在许多南极的大部分地区都持续存在）。鉴于未来的气候变化和预计在南极大陆内发生的降雪变化，迫切需要迫切需要进行卡塔巴氏运输过程的基本理解和建模能力的进步。该项目将利用研究人员的多学科团队的专业知识（具有冰圈科学，环境流体力学和大气科学的背景）来解决这些知识差距。2。对项目的技术描述，该项目指出要研究的问题，研究的目标和范围以及要使用的方法和方法。在许多情况下，技术项目描述可能是提交提交的项目摘要的修改版本。使用野外观测和直接的katabatic流量数值模拟，这是预期的 - 首次导致katabatic流的表面层相似性理论，将湍流与平均垂直梯度有关。相似性理论将用于开发大型涡流模拟（LES）的表面边界条件，实现了katabatic流的第一个准确的LE。开发简单的模型来推断基于卫星遥感和区域气候模型的雪运输，该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估来获得支持。