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arXiv · 2505.17213

Wind shear and the role of eddy vapor transport in driving water convection on Jupiter

Abstract

Recent observations of convection in the jovian atmosphere have demonstrated that convection is strongly concentrated at specific locations on planet. For instance, observations of lightning show that the cyclonic features (e.g,. belts and folded filamentary regions - FFRs) show increased convective activity compared to anti-cyclonic regions. Meanwhile, the distribution of ammonia and water vapor show a large enrichment near the equator, which is also suggestive of strong upwelling and convective activity. Marrying these different observations is challenging due to a lack of data concerning the characteristics of the deep jovian atmosphere, and a resulting inability to observe the true deep source of the various convective phenomena. To understand the nature of these convective events and \paperedit{the role of the } structure of the deep atmosphere \paperedit{in driving convective events}, we run simulations of cloud formation and convection using the Explicit Planetary hybrid-Isentropic Coordinate General Circulation Model (EPIC GCM). We vary the dynamics of the atmosphere by parameterizing the deep wind shear and studying the resulting effect on the strength, frequency and distribution of convective storms. We find that convection in our model is strongly tied to the local dynamics and the deep wind shear. We further decompose the generation of convective available potential energy (CAPE) into three components (thermal, mechanical, and moist/chemical), and find that the chemical mechanism is the strongest component, working to advect water vapor from moisture-rich regions to moisture-poor regions and to drive convection along a ``moisture front.''

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Ramanakumar Sankar, Michael H Wong, Csaba Palotai, Shawn Brueshaber. 2025-05-22. Wind shear and the role of eddy vapor transport in driving water convection on Jupiter. https://doi.org/10.3847/psj%2Fadcc21

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