Turbulent oceans and atmospheres of the rotating planets

你有没有想过为什么气候很难预测？其中一个主要原因是气候系统的组成部分，如地球的海洋和大气，是非线性的，本质上是混沌的。我的研究计划的总体目标是更好地了解控制海洋和大气中分层和旋转流体的非线性行为的动力学过程。同样的过程通常与其他行星的大气有关，包括气体巨星木星和土星。这项研究将提高我们预测这些复杂的非线性流体动力系统的动力学和演化的能力。海洋和大气具有普遍的大尺度环流，但又富含小得多的流场和密度场。水流湍急，包含大量的漩涡。这些漩涡与行星尺度的(罗斯比)波相互作用，这是由于行星的自转和曲率造成的。这些运动影响了海洋中的生物生产、混合和动量的消散，但它们的动力学细节，包括它们的来源和生命周期，尚不完全清楚。这项研究计划的重点是产生急流、涡旋和罗斯比波。我们的方法结合了理论、数值模拟和实验室实验。我们使用我们开发的一种新的实验室技术来远程测量旋转流体中的压力、速度和涡量。我们把这项技术称为‘高度计成像测速’，它与卫星测高没有什么不同，它在20世纪90年代初发射了第一颗卫星高度计，给物理海洋学带来了革命性的变化。实验室测高提供了高分辨率的速度场，使实验室实验在流动的详细渲染方面与当前的3D数值模型相当或超过。使用这种方法的研究结果将会对那些致力于将非地转动力学纳入传统上对海洋和大气的准地转理想化的研究的社区产生极大的兴趣。这项我们已经开发并正在继续探索和应用的技术，使加拿大的尖端研究成为可能。这项研究将对湍流海洋和大气的非线性动力学产生新的结果和理解。

Have you ever wondered why climate is extremely difficult to predict? One of the major reasons is that the components of the climate system such as the Earth's oceans and atmosphere are nonlinear and inherently chaotic. The overall goal of my research program is to better understand the dynamical processes that govern the nonlinear behavior of the stratified and rotating fluids that comprise the oceans and atmosphere. The same processes are often relevant for atmospheres of other planets including gas giants Jupiter and Saturn. This study will enhance our capability to predict the dynamics and evolution of these complex nonlinear fluid dynamical systems. The oceans and atmosphere have a general large-scale circulation, and yet are rich with flow fields and density fields of much smaller scale. The flows are turbulent and contain eddies in abundance. The eddies interact with planetary-scale (Rosby) waves which are due to rotation and curvature of the planet. These motions influence biological production, mixing, and dissipation of momentum in the ocean but the details of their dynamics including their sources and life-cycle are yet to be fully understood. This research program focuses on the production of jet-like currents, eddies and Rossby waves. Our approach combines theory, numerical simulations and laboratory experiments. We use a new laboratory technique that we developed to remotely measure pressure, velocity and vorticity in a rotating fluid. We call this technique 'Altimetric Imaging Velocimetry' and it is not unlike satellite altimetry which revolutionized physical oceanography with the launch of the first satellite altimeters in the early 1990s. Laboratory altimetry provides high resolution velocity field such that laboratory experiments equal or exceed current 3D numerical models in detailed rendering of the flow. The results of the research using this method will be of great interest for communities involved in addressing 'spontaneous imbalance' or 'jets and annular structures in geophysical fluid dynamics' who are working to include non-geostrophic dynamics in what traditionally have been quasi-geostrophic idealizations of ocean and atmosphere. This technique, that we have developed and are continuing to explore and apply, enables cutting edge research here in Canada. This research will yield new results on and understanding of nonlinear dynamics of turbulent oceans and atmosphere.