The Oxygen Cycle

Oxygen is essential for life......  (e.g. respiration, stratospheric ozone)
     ...... but what supplies the oxygen consumed by living beings?
  • oxygen is created by photosynthesis and net emission due to burial of atmospheric carbon (CO2)
  • oxygen is consumed by both living beings and the net uptake of oxygen due to weathering of fossilized carbon

  • ...... where does most of the oxygen in the Earth system reside?
  • most of the Earth's oxygen resides in mineral oxides of the crust
  • a small fraction resides in the atmosphere and an even smaller fraction resides in the biosphere
  • still the biosphere is crucial to understanding the atmospheric oxygen budget as it controls short term exchanges between sediments and the atmosphere
  •        ...... how long will atmospheric oxygen last?

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    a link to the worksheet
    if you're curious about our upcoming study of the carbon cycle, check out these figures that estimate your production of carbon