Deep model simulation of polar vortices in gas giant atmospheres
| Autor: | F. R. N. Chambers, Anna L. Watts, Ferran Garcia |
|---|---|
| Přispěvatelé: | Universitat Politècnica de Catalunya. Departament de Mecànica de Fluids, Universitat Politècnica de Catalunya. GReCEF- Grup de Recerca en Ciència i Enginyeria de Fluids, High Energy Astrophys. & Astropart. Phys (API, FNWI) |
| Rok vydání: | 2020 |
| Předmět: |
Astrofísica
Convection 010504 meteorology & atmospheric sciences simulations [Software] Gas giant FOS: Physical sciences Astrophysics 01 natural sciences Jupiter Magnetohydrodynamics Polar vortex Saturn 0103 physical sciences 010303 astronomy & astrophysics Physics::Atmospheric and Oceanic Physics 0105 earth and related environmental sciences Earth and Planetary Astrophysics (astro-ph.EP) Physics turbulence Fluid Dynamics (physics.flu-dyn) Giant planet Astronomy and Astrophysics Physics - Fluid Dynamics 76-10 76F35 86-10 Vortex gaseous planets [Planets and satellites] Physics - Atmospheric and Oceanic Physics 13. Climate action Space and Planetary Science Física::Astronomia i astrofísica [Àrees temàtiques de la UPC] Atmospheric and Oceanic Physics (physics.ao-ph) Physics::Space Physics Polar Astrophysics::Earth and Planetary Astrophysics Astrophysics - Earth and Planetary Astrophysics |
| Zdroj: | Monthly Notices of the Royal Astronomical Society Monthly Notices of the Royal Astronomical Society, 499(4), 4698-4715. Oxford University Press Monthly Notices of the Royal Astronomical Society 499(2020)4, 4 UPCommons. Portal del coneixement obert de la UPC Universitat Politècnica de Catalunya (UPC) |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1093/mnras/staa2962 |
| Popis: | The Cassini and Juno probes have revealed large coherent cyclonic vortices in the polar regions of Saturn and Jupiter, a dramatic contrast from the east-west banded jet structure seen at lower latitudes. Debate has centered on whether the jets are shallow, or extend to greater depths in the planetary envelope. Recent experiments and observations have demonstrated the relevance of deep convection models to a successful explanation of jet structure and cyclonic coherent vortices away from the polar regions have been simulated recently including an additional stratified shallow layer. Here we present new convective models able to produce long-lived polar vortices. Using simulation parameters relevant for giant planet atmospheres we find flow regimes that are in agreement with geostrophic turbulence (GT) theory in rotating convection for the formation of large scale coherent structures via an upscale energy transfer fully three-dimensional. Our simulations generate polar characteristics qualitatively similar to those seen by Juno and Cassini: they match the structure of cyclonic vortices seen on Jupiter; or can account for the existence of a strong polar vortex extending downwards to lower latitudes with a marked spiral morphology and the hexagonal pattern seen on Saturn. Our findings indicate that these vortices can be generated deep in the planetary interior. A transition differentiating these two polar flows regimes is described, interpreted in terms of different force balances and compared with previous shallow atmospheric models which characterised polar vortex dynamics in giant planets. In addition, the heat transport properties are investigated confirming recent scaling laws obtained in the context of reduced models of GT. Comment: 18 pages, 13 figures and 3 tables |
| Databáze: | OpenAIRE |
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