论文标题
金星大气的长期演变:过程和反馈机制
The long-term evolution of the atmosphere of Venus: processes and feedback mechanisms
论文作者
论文摘要
这项工作回顾了金星大气的长期演变,并通过内部循环调节其组成。金星大气的形成和演变导致当代的表面条件,仍然是辩论的主题,并涉及与许多学科联系在一起的问题。我们探索了这些各种相关的机制,这些机制从挥发性来源和水槽开始,塑造了大气的演变。从深内部到大气的顶部,我们描述了火山量超出,表面大气相互作用以及大气逃脱。此外,我们解决了金星历史的更复杂的方面,包括后期积聚的作用,磁场的产生如何与长期演化相关,以及地球化学和地球动力学反馈周期对大气进化的影响。我们强调了基于建模和观察结果,从积聚到当今状态,金星本可以遵循的合理的终端成员进化途径。在第一种情况下,在岩浆海洋阶段,大气逃生将行星干燥。在第二种情况下,金星可以长时间藏有表面液态水,直到其温带气候不稳定并进入失控的温室阶段。在第三种情况下,金星的效率低下可能会使水在地球内保持水,其中氢被困在核心中,地幔被氧化。我们讨论了现有的证据和未来的观察和任务,以完善我们对地球历史的理解,以及在过去,现在或将来一直运行的内部,表面和气氛之间复杂的反馈周期。
This work reviews the long-term evolution of the atmosphere of Venus, and modulation of its composition by interior-exterior cycling. The formation and evolution of Venus's atmosphere, leading to contemporary surface conditions, remain hotly debated topics, and involve questions that tie into many disciplines. We explore these various inter-related mechanisms which shaped the evolution of the atmosphere, starting with the volatile sources and sinks. Going from the deep interior to the top of the atmosphere, we describe volcanic outgassing, surface atmosphere interactions, and atmosphere escape. Furthermore, we address more complex aspects of the history of Venus, including the role of Late Accretion impacts, how magnetic field generation is tied into long-term evolution, and the implications of geochemical and geodynamical feedback cycles for atmospheric evolution. We highlight plausible end-member evolutionary pathways that Venus could have followed, from accretion to its present-day state, based on modeling and observations. In a first scenario, the planet was desiccated by atmospheric escape during the magma ocean phase. In a second scenario, Venus could have harbored surface liquid water for long periods of time, until its temperate climate was destabilized and it entered a runaway greenhouse phase. In a third scenario, Venus's inefficient outgassing could have kept water inside the planet, where hydrogen was trapped in the core and the mantle was oxidized. We discuss existing evidence and future observations and missions required to refine our understanding of the planet's history and of the complex feedback cycles between the interior, surface, and atmosphere that have been operating in the past, present or future of Venus.