Turbulent oceans and atmospheres of the rotating planets: down to small scale

旋转行星的湍流海洋和大气：小到小尺度

• 批准号: RGPIN-2019-04957
• 负责人: Afanassiev, Iakov
• 金额: $ 2.19万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714186
• 关键词: Turbulent; oceans; atmospheres; rotating; planets

The ability to predict climate is one of the vital problems in science. Climate systems include the Earth's oceans and atmosphere and are notoriously difficult to predict because of inherently turbulent nature of flows. My overall research objective is to better understand the dynamical processes that govern the behavior of the stratified and rotating fluids that comprise the Earth's oceans and atmosphere, as well as the atmospheres of other planets. Dynamical processes relevant to fluids on Earth are often similar to those on other planets. In this coming grant cycle the focus will be on thermal convection. This is a process which can be easily observed in your kitchen on small scale, yet it drives circulations of planetary atmospheres. Examples include bands and vortices on Jupiter and Saturn; wealth of data on these flows was recently provided by Juno and Cassini spacecrafts. Within an oceanographic context, our objective is to investigate turbulence at the range from the submeso-scale to a large-scale where the beta-effect is important. Mixing and the Lagrangian transport of tracers and drifters by turbulent motions of different scales are of particular interest. Our approach includes both theory and numerical simulations, and we also employ laboratory experiments to study geophysical flows. Our laboratory tank is less than two meters across but can be rotated fast around its axis. This setup allows us to create an idealized “ocean” or “atmosphere” of a rotating planet. We use a state-of-the-art measuring technique which we have been developing here in our lab. We call it the Altimetric Image Velocimetry. With this technique the data can be collected with precision and high resolution. Our laboratory tank can be thought of as an analogue computer where we can run numerous simulations/experiments with real fluid. The experiments do not require any assumptions which are routinely used in numerical simulations dealing with “virtual” fluid. This research will yield new results on the flows driven by convection and contribute to our understanding of nonlinear dynamics of turbulent oceans and atmospheres. The outcome of the proposed research will be of interest for oceanographic and atmospheric science communities who are working to include non-geostrophic dynamics in what traditionally have been quasi-geostrophic idealizations of ocean and atmosphere.

预测气候的能力是科学中的重要问题之一。气候系统包括地球的海洋和大气层，众所周知，由于流动的固有湍流性质，很难预测。 我的总体研究目标是更好地了解动力学过程，这些动力学过程支配着地球海洋和大气以及其他行星大气层中分层和旋转流体的行为。与地球上的流体有关的动力学过程通常与其他行星上的相似。在即将到来的资助周期中，重点将放在热对流上。这是一个在你的厨房里很容易观察到的小规模过程，但它驱动着行星大气的循环。例子包括木星和土星上的带和漩涡;朱诺号和卡西尼号航天器最近提供了关于这些流动的大量数据。在海洋学的背景下，我们的目标是调查湍流的范围从次中尺度到大尺度的β效应是重要的。混合和拉格朗日运输的示踪剂和漂流物的湍流运动的不同尺度的特别感兴趣。 我们的方法包括理论和数值模拟，我们还采用实验室实验来研究地球物理流。我们的实验室水槽直径不到两米，但可以绕着它的轴快速旋转。这种设置使我们能够创造一个理想化的“海洋”或“大气”的旋转行星。我们使用我们在实验室开发的最先进的测量技术。我们称之为高度图像测速。通过这种技术，可以精确和高分辨率地收集数据。我们的实验室水箱可以被认为是一台模拟计算机，我们可以用真实的流体进行大量的模拟/实验。实验不需要任何假设，通常用于处理“虚拟”流体的数值模拟。 这项研究将产生新的结果，对流驱动的流动，并有助于我们了解湍流海洋和大气的非线性动力学。拟议研究的结果将是海洋学和大气科学界的兴趣，他们正在努力将非地转动力学纳入传统上一直是海洋和大气的准地转理想化。