The dynamics of jets in geophysical turbulence

研究领域：流体动力学和空气动力学：众所周知，在行星涡度梯度存在的情况下，旋转湍流具有组织成纬向（东西向）喷流的强烈趋势。《自然》杂志上的例子包括巨行星上的带状喷流，特别是木星和土星，以及在南大洋观察到的喷流。该项目的目的是通过研究这些喷流在一系列日益复杂和现实的模型中的形成，提高我们对这些喷流物理学的理论理解。准地转β平面湍流的单层模型是一个简单的、被广泛研究的模型。该项目将利用非平衡统计力学的方法来理解和解释该模型中的射流形成行为。特别令人感兴趣的是最近发现的“迁移喷流”机制，其动力学起源至今无法解释。该项目将继续考虑更复杂的三维模型的结果。以木星为例，最近的朱诺号使命已经确定，喷流深入到行星内部。如何以及国家的最先进的大气环流模型的结果捕捉正确的射流深度的问题将进行探讨，特别是在何种程度上的朱诺结果可以用来约束模型参数的重点。

Research Areas: Fluid dynamics and Aerodynamics.It is well known that rotating turbulent flows, in the presence of a planetary vorticity gradient, have a strong tendency to organise into zonal (east-west) jets. Examples in Nature include the banded jets on the giant planets, particularly Jupiter and Saturn, and those observed in the Southern ocean.The aim of the project is to improve our theoretical understanding of the physics of these jets by studying their formation in a hierarchy of models ofincreasing complexity and realism. One simple, widely explored model is the single-layer model of quasi-geostrophic beta-plane turbulence. The project will exploit methods from non-equilibrium statistical mechanics to understand and interpret the jet formation behaviour in this model. Of particular interest is a recently discovered 'migrating jet' regime, the dynamical origin of which is hitherto unexplained.The project will continue by considering results from more sophisticated three-dimensional models. In the case of Jupiter, the recent Juno mission has established that the jets penetrate deep into the interior of the planet. The question of how well state-of-the-art general circulation model results capture the correct jet depth will be explored, with a particular focus on the extent to which the Juno results can be used to constrain model parameters.