Moderately High Obliquity Promotes Biospheric Oxygenation

Abstract Planetary obliquity is a first-order control on planetary climate and seasonal contrast, which has number of cascading consequences for life. How moderately high (obliquities greater than Earth’s current up to 45°) affects planet’s surface physically been studied previously, but we lack an understanding how marine life will respond these conditions. We couple the ROCKE-3D general circulation model cGENIE 3D biogeochemical simulate ocean biosphere’s response various obliquities, bioessential nutrient inventories, biospheric structure. find that net rate photosynthesis increased by 35% sea-to-air flux biogenic oxygen doubled between 0° 45° scenarios, equivalent doubling nutrients. Our results suggest planets have higher potential oxygenation their low-obliquity counterparts habitable may be easier detect with next-generation telescopes. These also more conducive evolution complex