The turbulent dynamics of Jupiter’s and Saturn’s weather layers: order out of chaos?
| Autor: | Roland M. B. Young, Peter L. Read, D. Kennedy |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Atmospheres
010504 meteorology & atmospheric sciences Gas giant Rossby radius of deformation FOS: Physical sciences 01 natural sciences Jupiter Planet Saturn 0103 physical sciences Great Red Spot General circulation model lcsh:Science 010303 astronomy & astrophysics Physics::Atmospheric and Oceanic Physics 0105 earth and related environmental sciences Earth and Planetary Astrophysics (astro-ph.EP) lcsh:QE1-996.5 Giant planet Geophysics Weather layer Dynamics lcsh:Geology Planetary science 13. Climate action 85-02 Physics::Space Physics General Earth and Planetary Sciences lcsh:Q Astrophysics::Earth and Planetary Astrophysics Geology Astrophysics - Earth and Planetary Astrophysics |
| Zdroj: | Geoscience Letters Geoscience Letters, Vol 7, Iss 1, Pp 1-18 (2020) |
| DOI: | 10.1186/s40562-020-00159-3 |
| Popis: | The weather layers of the gas giant planets, Jupiter and Saturn, comprise the shallow atmospheric layers that are influenced energetically by a combination of incoming solar radiation and localised latent heating of condensates, as well as by upwelling heat from their planetary interiors. They are also the most accessible regions of those planets to direct observations. Recent analyses in Oxford of cloud-tracked winds on Jupiter have demonstrated that kinetic energy is injected into the weather layer at scales comparable to the Rossby radius of deformation and cascades both upscale, mostly into the extra-tropical zonal jets, and downscale to the smallest resolvable scales in Cassini images. The large-scale flow on both Jupiter and Saturn appears to equilibrate towards a state which is close to marginal instability according to Arnol'd's 2nd stability theorem. This scenario is largely reproduced in a hierarchy of numerical models of giant planet weather layers, including relatively realistic models which seek to predict thermal and dynamical structures using a full set of parameterisations of radiative transfer, interior heat sources and even moist convection. Such models include the Jason GCM, developed in Oxford, which also represents the formation of (energetically passive) clouds of NH3, NH4SH and H2O condensates and the transport of condensable tracers. Recent results show some promise in comparison with observations from the Cassini and Juno missions, but some observed features (such as Jupiter's Great Red Spot and other compact ovals) are not yet captured spontaneously by any weather layer model. We review recent work in this vein and discuss a number of open questions for future study. 27 pages, including 7 figures. Submitted to Geoscience Letters as invited review from 2019 assembly of the Asia-Oceania Geosciences Society |
| Databáze: | OpenAIRE |
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