近日，以色列魏茨曼科学研究所Nimrod Gavriel团队研究了木星极地气旋垂直结构的动力学约束。相关论文发表在2025年10月28日出版的《美国科学院院刊》杂志上。

木星的两极特征是引人注目的多边形气旋，随着时间的推移向西漂移，这是一种由β漂移控制的运动（由科里奥利力的纬度变化引起的涡旋运动）。

研究组探讨了β漂移和由此产生的向西运动如何取决于这些气旋的深度。与直觉相反的是，较浅的气旋漂移得更慢，这是涡流拉伸更强的结果。通过使用木星极地的二维准地转模型，研究组限制了气旋的变形半径，这是一个关键参数，可以代表它们的垂直范围，需要复制观测到的向西漂移。

然后，研究组通过解决将2D模型连接到3D框架的特征值问题来探索可能的垂直结构和极点的静态稳定性，从而匹配约束变形半径。这些发现为解释即将到来的朱诺号对木星北极的微波测量提供了基础，为极地气旋的静态稳定性和垂直结构提供了见解。他们利用长期运动作为垂直动力学的约束，这项工作为推进他们对木星神秘的极地气旋的形成和演化的理解奠定了基础。

附：英文原文

Title: Dynamical constraints on the vertical structure of Jupiter’s polar cyclones

Author: Gavriel, Nimrod, Kaspi, Yohai

Issue&Volume: 2025-10-28

Abstract: Jupiter’s poles feature striking polygons of cyclones that drift westward over time, a motion governed by β-drift (vortex motion caused by the latitudinal variation of the Coriolis force). This study investigates how β-drift and the resulting westward motion depend on the depth of these cyclones. Counterintuitively, shallower cyclones drift more slowly, a consequence of stronger vortex stretching. By employing a 2D quasi-geostrophic model of Jupiter’s polar regions, we constrain the cyclones’ deformation radius, a key parameter that serves as a proxy for their vertical extent, required to replicate the observed westward drift. We then explore possible vertical structures and the static stability of the poles by solving the eigenvalue problem that links the 2D model to a 3D framework, matching the constrained deformation radius. These findings provide a foundation for interpreting upcoming Juno microwave measurements of Jupiter’s north pole, offering insights into the static stability and vertical structure of the polar cyclones. Thus, by leveraging long-term motion as a constraint on vertical dynamics, this work sets the stage for advancing our understanding of the formation and evolution of Jupiter’s enigmatic polar cyclones.

DOI: 10.1073/pnas.2503737122

Source: https://www.pnas.org/doi/abs/10.1073/pnas.2503737122