Atmospheric evolution: from early Earth to exoplanets

大气演化：从早期地球到系外行星

• 批准号: RGPIN-2018-05929
• 负责人: Goldblatt, Colin
• 金额: $ 3.13万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=750973
• 关键词: Atmospheric; evolution; early; Earth; exoplanets

Terrestrial planet atmospheres are awesome. They are the mixing pot of every waste gas from the planet, gasses from everything from microbes to the mantle, processed by photochemistry and geochemistry. Atmospheric composition largely determines what life can live at the surface and controls planetary climate by setting the strength of the greenhouse effect and how much sunlight is absorbed. As we enter the age of exoplanets, atmospheres are our window to other worlds; remote atmospheric characterization is the means by which exoplanets may be explored and ultimately life may be detected. My research program is about the evolution of planetary atmospheres, for inhabited planets (just Earth right now), for comparison planets and moons in the solar system (Venus, Mars, Titan and more) and, increasingly, for exoplanets. The objectives of the proposed research are: to improve our understanding of the coupled climate-geochemical-biosphere evolution of Earth throughout its history; to develop theory of planetary evolution in a comparative planetology framework, linking Earth to the other terrestrial planets; and to apply this theory to developing methodology for discerning whether exoplanets are habitable or inhabited. We will research across four themes: (A) Evolution of Earth's atmosphere, modelling cycles of nitrogen, carbon and oxygen and the atmospheric inventories of N2, O2, CO2, CH4, N2O and NH3, linking geochemical and climate changes. We will look at the Great Oxidation and snowball Earth glacials, and change throughout Earth history. (B) Climate of Earth's deep past, using 3-D climate models to understand the climate system and clouds in particular, and a project to verify the accuracy of the radiation codes used in these models. (C) Atmospheric evolution on other planets and moons, studying the transition of Venus through a runaway greenhouse and the weird atmosphere of Titan (D) (Exo)planet habitability, developing theory on which planets could harbour life, and how the "habitable zone" depends on atmospheric composition and water inventory. The proposed work addresses fundamental "blue-sky" questions relating, contributing novel theory to how the Earth and terrestrial planets have evolved. It will directly contribute to developing methodology for exoplanet life detection and characterization, which will be a rapidly expanding field over the next few decades and utilize major Canadian assets. It will be applied to improved understanding of anthropogenic climate change, as exploring Earth history provides the context for modern-day changes. A particularly novel aspect of my research program is the interdisciplinary breadth: we tackle problems in climate science, geochemistry and atmospheric chemistry, geology, astronomy and planetary sciences as necessary to understand the evolution of our, and other, atmospheres.

陆地行星氛围很棒。它们是地球上每种废气的混合锅，从微生物到地幔的所有东西，通过光化学和地球化学处理。大气组成在很大程度上决定了在表面上可以生活的生命，并通过设定温室效应的强度以及吸收了多少阳光来控制行星气候。当我们进入系外行星时代时，气氛是我们进入其他世界的窗口。遥远的大气表征是可以探索系外行星并最终检测到生命的手段。我的研究计划是关于行星氛围的演变，用于居住的行星（正是地球），用于太阳系（金星，火星，泰坦等）中的比较行星和卫星，以及越来越多的外部球星。拟议的研究的目标是：提高我们对地球在整个历史中的耦合气候 - 地球化学的进化的理解；在比较行星学框架中发展行星进化理论，将地球与其他陆地行星联系起来；并将这种理论应用于开发方法，以辨别外部行星是居住还是居住的方法。我们将研究四个主题：（a）地球大气的进化，建模氮，碳和氧气以及N2，O2，O2，CO2，CH4，CH4，N2O和NH3的大气发明，将地球化学和气候变化联系起来。我们将研究巨大的氧化和雪球冰川，并在整个地球历史上发生变化。 （b）地球深处的气候，使用3-D气候模型特别了解气候系统和云，以及一个项目，以验证这些模型中使用的辐射码的准确性。 （c）在其他行星和卫星上的大气进化，研究金星通过失控的温室和泰坦（D）（EXO）行星的怪异气氛的过渡，发展了理论，在哪些行星上可以掩盖生命，以及“可居住区”如何取决于大气组成和水分。拟议的工作解决了基本的“蓝色”问题，这是关于地球和地球行星如何发展的小说理论。它将直接有助于开发用于系外行星生命检测和表征的方法，这将在未来几十年中迅速扩展，并利用加拿大的主要资产。它将应用于改善对人为气候变化的理解，因为探索地球历史为现代变化提供了背景。我的研究计划的一个特别新颖的方面是跨学科的广度：我们根据需要了解气候科学，地球化学和大气化学，地质学，天文学和行星科学的问题，以了解我们和其他大气的演变。