Vortices, waves, and energy cascades in atmospheric turbulence

大气湍流中的涡流、波和能量级联

基本信息

批准号：
RGPIN-2020-07001
负责人：
Waite, Michael
金额：
$ 4.44万
依托单位：
University of Waterloo
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2021
资助国家：
加拿大
起止时间：
2021-01-01 至 2022-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741537
关键词：
Vortices waves energy cascades atmospheric

项目摘要

Atmospheric fluid mechanics spans a wide range of length scale, from planetary scales down to millimetre scales. The mesoscale is an intermediate range of scales from kilometres to hundreds of kilometres; it supports an amazing variety of phenomena, including vortices, gravity waves, convective storms, and turbulence. Mesoscale dynamics play a key role in the energy budget of the atmosphere. Kinetic energy is primarily stored in large-scale vortices, and dissipated by very small-scale vortices; to reach the dissipation scales, energy must pass through the mesoscale. The transfers of energy between different scales in the mesoscale is called the mesoscale cascade. Despite its importance, this process is not completely understood and not fully captured by numerical weather prediction models. This research program aims to improve the representation of the mesoscale cascade in atmospheric models by gaining fundamental understanding of this process. There are three main objectives of this program: to understand the role of nonlinear waves and vortices in the mesoscale cascade; to quantify the exchanges of energy by different processes at different scales; and to improve the representation of small-scale turbulence in numerical models, especially localized upscale energy transfer. The work proposed here will deepen the fundamental understanding of atmospheric dynamics, improve the ability of numerical weather models to predict small-scale phenomena, and train students in atmosphere/ocean/climate dynamics and modelling, as well as for a variety of careers in computational modelling and data analysis.

大气流体力学涵盖了从行星尺度到毫米尺度的广泛长度尺度。中尺度是从公里到数百公里的中间尺度范围；它支持各种各样的现象，包括涡流、重力波、对流风暴和湍流。中尺度动力学在大气能量收支中发挥着关键作用。动能主要储存在大尺度涡旋中，并通过极小尺度涡旋耗散；为了达到耗散尺度，能量必须穿过介尺度。介尺度中不同尺度之间的能量转移称为介尺度级联。尽管它很重要，但这个过程尚未被完全理解，也没有被数值天气预报模型完全捕获。该研究计划旨在通过获得对中尺度级联过程的基本了解来改善大气模型中中尺度级联的表示。该计划有三个主要目标：了解非线性波和涡旋在中尺度级联中的作用；量化不同规模的不同过程的能量交换；并改进数值模型中小尺度湍流的表示，特别是局部的高档能量转移。这里提出的工作将加深对大气动力学的基本理解，提高数值天气模型预测小规模现象的能力，并培训学生大气/海洋/气候动力学和建模以及计算方面的各种职业建模和数据分析。