Oceans on the edge of anoxia

  title={Oceans on the edge of anoxia},
  author={Andrew J. Watson},
  pages={1529 - 1530}
  • A. Watson
  • Published 23 December 2016
  • Environmental Science, Geography
  • Science
Environmental crises can tip the ocean into O2 depletion For the past several hundred million years, oxygen concentrations in Earth's atmosphere have been comparatively high (1, 2). Yet, the oceans seem never to have been far from anoxia (oxygen depletion) and have occasionally suffered major oceanic anoxic events (OAEs), recognized in the rock record through accumulations of dark, organic-rich shales (3). OAEs seem to be promoted by warm climates, and some have been associated with major… 

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