Land-atmosphere Interaction over complex terrain: Hydrology and Large Eddy Simulation

复杂地形上的陆地-大气相互作用：水文学和大涡模拟

• 批准号: RGPIN-2015-05609
• 负责人: Parlange, Marc
• 金额: $ 3.42万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613645
• 关键词: Land; atmosphere; Interaction; over; complex

Mountain meteorological processes cover a wide range of interacting scales that introduce challenges for numerical weather prediction. In fact, in mountainous regions, exceptions are often the rule in the sense that standard theories, measurement techniques, analysis techniques, and parameterizations are usually not strictly valid. In this project, we will attempt to attack some of these existing difficulties by taking advantage of new measurement techniques that our team will deploy to study physical processes over scales ranging from the microscale (i.e., dissipation scales of turbulence, O(1mm)) into the meso-gamma scale. We will gain improved understanding of flow physics in mountainous terrain through a multifaceted approach utilizing field experiments, newly developed and state-of-the-art instrumentation and numerical simulations of slope flows and blowing snow. The major aims of this project are to utilize novel instrumentation techniques in field campaigns and develop new generation numerical tools for: (i) improved understanding of critical mountain terrain science issues and (ii) improved simulations of slope flows and snow transport. The main experimental part of the project will be a field campaign to be conducted in the Dischma Valley of the Swiss Alps. Near surface processes in mountainous terrain can be particularly important in events related to fog formation, forest fires, snowmelt, and air quality, where models designed for flat open terrain are often applied over mountainous regions. In addition, near surface dynamical flow processes can be extremely important in understanding snow transport processes in alpine terrain. While many excellent field and numerical studies have been conducted, there are still a number of open important questions that remain to be answered. Here, we aim to answer a subset of those questions through targeted field experiments with specialized instrumentation and new developments in Large Eddy Simulation (LES) for slope flows and snow transport over snow/ice surfaces. Given the breadth of this research area, we will focus our efforts on several key scientific questions related to near surface processes in mountain terrain. Specifically, we will look to answer the following questions related to physical processes in mountain terrain: 1. Can the surface energy budget be closed on steep heterogeneous mountainous slopes using new fast response instruments for measuring latent and sensible heat fluxes and carefully accounting for advection and energy storage? 2. What are the dominant physical mechanisms governing transport dynamics during morning and evening transition periods? 3. What mechanisms drive surface shear stress in atmospheric flows? 4. Can LES simulations of air movement and snow transport reliably represent the underlying physics.

山气象过程涵盖了广泛的相互作用量表，这些量表引入了数值天气预测的挑战。实际上，在山区，在标准理论，测量技术，分析技术和参数化的意义上，例外通常是规则。在这个项目中，我们将尝试通过利用新的测量技术来攻击其中的一些现有困难，我们的团队将部署这些技术来研究物理过程，从微观尺度（即湍流的耗散量表，O（1mm））中的尺度上进行研究，以了解中等量表。我们将利用现场实验，新开发和最先进的仪器以及坡度流和吹雪的数值模拟的多方面方法来提高人们对山区流量物理的了解。 该项目的主要目的是在现场活动中利用新颖的仪器技术，并开发新一代的数值工具：（i）对关键山地科学问题的了解得以提高，以及（ii）改善对坡度流和雪的模拟的模拟。该项目的主要实验部分将是将在瑞士阿尔卑斯山的迪斯玛山谷进行的现场运动。 在与雾形成，森林大火，融雪和空气质量有关的事件中，山区地形的近地面过程尤其重要，在该事件中，通常在山区上使用专为平坦的开放地形设计的模型。此外，近表面动态流动过程对于理解高山地形的雪运过程至关重要。尽管已经进行了许多出色的领域和数值研究，但仍有许多开放的重要问题有待回答。在这里，我们的目标是通过针对性的仪器实验来回答这些问题的一部分，该实验具有专门的仪器和大型涡流模拟（LES）的新开发项目，用于坡度流和雪/冰面上的雪运输。 鉴于该研究领域的广度，我们将重点放在与山地近地面过程有关的几个关键科学问题上。具体来说，我们将寻求回答与山区物理过程有关的以下问题： 1。是否可以使用新的快速响应仪器在陡峭的异质山坡上关闭表面能预算，以测量潜在和明智的热通量并仔细考虑对流和储能？ 2。在早晨和晚上过渡期间，控制运输动力的主要物理机制是什么？ 3。哪些机制驱动大气流中的表面剪切应力？ 4。可以可靠地模拟空气流动和雪运输的基础物理。