Observations of Jupiter's deep atmosphere by the Juno spacecraft have revealed several puzzling facts: The concentration of ammonia is variable down to pressures of tens of bars and is strongly dependent on latitude. While most latitudes exhibit a low abundance, the Equatorial Zone of Jupiter has an abundance of ammonia that is high and nearly uniform with depth. In parallel, the Equatorial Zone is peculiar for its absence of lightning, which is otherwise prevalent most everywhere else on the planet. We show that a model accounting for the presence of small‐scale convection and water storms originating in Jupiter's deep atmosphere accounts for the observations. Where strong thunderstorms are observed on the planet, we estimate that the formation of ammonia‐rich hail (“mushballs”) and subsequent downdrafts can deplete efficiency the upper atmosphere of its ammonia and transport it efficiently to the deeper levels. In the Equatorial Zone, the absence of thunderstorms shows that this process is not occurring, implying that small‐scale convection can maintain a near‐homogeneity of this region. A simple model satisfying mass and energy balance accounts for the main features of Juno's microwave radiometer observations and successfully reproduces the inverse correlation seen between ammonia abundance and the lightning rate as function of latitude. We predict that in regions where ammonia is depleted, water should also be depleted to great depths. The fact that condensates are not well mixed by convection until far deeper than their condensation level has consequences for our understanding of Jupiter's deep interior and of giant‐planet atmospheres in general.

中文翻译：

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木星的风暴和氨的消耗：II。解释朱诺观测

朱诺号航天器对木星深空的观测揭示了几个令人费解的事实：氨的浓度可降低到数十巴的压力，并且强烈依赖于纬度。尽管大多数纬度显示出较低的丰度，但木星赤道带的氨含量很高，并且深度上几乎均匀。同时，由于没有闪电，因此赤道带是奇特的，否则，闪电在地球上其他任何地方都最为普遍。我们表明，一个模型解释了源自木星深层大气的小规模对流和水暴的存在。在地球上观测到强雷暴的地方，我们估计富含氨的冰雹（“蘑菇球”）的形成和随后的向下气流会耗尽其氨气的上部大气的效率，并将其有效地输送到更深的水平。在赤道带，没有雷暴表明没有发生这种过程，这意味着小规模对流可以维持该区域的近乎均匀。一个满足质量和能量平衡的简单模型可以说明朱诺微波辐射计观测的主要特征，并成功地再现了氨含量和雷电率之间的反相关关系（即纬度的函数）。我们预测在氨被耗尽的地区，水也应被耗尽至很深的深度。