Swansong biospheres: refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes

@article{OMalleyJames2012SwansongBR,
  title={Swansong biospheres: refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes},
  author={Jack T. O'Malley-James and Jane Greaves and John A. Raven and Charles S. Cockell},
  journal={International Journal of Astrobiology},
  year={2012},
  volume={12},
  pages={99 - 112}
}
The future biosphere on Earth (as with its past) will be made up predominantly of unicellular micro-organisms. [] Key Method A simple, latitude-based climate model incorporating eccentricity and obliquity variations is used as a guide to the temperature evolution of the Earth over the next 3 Gyr. This allows inferences to be made about potential refuges for life, particularly in mountains and cold-trap (ice) caves and what forms of life could live in these environments. Results suggest that in high latitude…
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Our present-day atmosphere is often used as an analog for potentially habitable exoplanets, but Earth's atmosphere has changed dramatically throughout its 4.5 billion year history. For example,
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Earth’s modern atmosphere is highly oxygenated and is a remotely detectable signal of its surface biosphere. However, the lifespan of oxygen-based biosignatures in Earth’s atmosphere remains
Implications of Tides for Life on Exoplanets.
TLDR
This work identifies the conditions under which tides may exert a significant positive influence on biotic processes including abiogenesis, biological rhythms, nutrient upwelling, and stimulating photosynthesis and identifies large-scale algal blooms as potential temporal biosignatures in reflectance light curves that can arise indirectly as a consequence of strong tidal forces.
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