Evolution of Earth-like Extrasolar Planetary Atmospheres: Assessing the Atmospheres and Biospheres of Early Earth Analog Planets with a Coupled Atmosphere Biogeochemical Model

• DOI: 10.1089/ast.2015.1384
• Publication Date: 2017-01-19T21:18:27Z
• Authors: S. Gebauer; J.L. Grenfell; J.W. Stock; R. Lehmann; M. Godolt; P. von Paris; H. Rauer
• Keywords: Early Earth; Biogeochemical Cycle; Biogeochemistry; Earth system science; Atmospheric chemistry; Planetary habitability

Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in Universe. The search for planets zone investigation their atmospheres with climate photochemical models a central focus exoplanetary science. Taking as reference planets, scientific goal understand what interactions were between atmosphere, geology, biology on early Earth. Great Oxidation Event (GOE) Earth's history was certainly caused by interplay, but controlling processes this occurrence are not well understood, study which will require interdisciplinary, coupled models. In work, we present results from newly developed Coupled Atmosphere Biogeochemistry model atmospheric O$_2$ concentrations fixed values inferred geological evidence. Applying unique tool, ours first quantitative analysis catalytic cycles that governed atmosphere near GOE. Complicated oxidation pathways play key role destroying O$_2$, whereas upper most formed abiotically via CO$_2$ photolysis. bistability found Goldblatt et al. (2006) observed calculations likely due detailed CH$_4$ scheme. We calculate increased increasing during For given surface flux, different states possible; however, net primary productivity (NPP) biosphere produces unique. Mixing, fluxes, ocean solubility, mantle/crust properties strongly affect NPP fluxes. Regarding exoplanets, "states" could exist similar biomass output. Strong activity lead false negatives life.